General Radiology: a few notes

Mesial temporal sclerosis

2011-12-23T08:07:00.000-08:00

MRI:
Small volume hippocampus on coronal volumeteric T1
Increased signal on coronal FLAIR
Small mamillary body
Small fornix
Temporal lobe atrophy
Ipsilateral white matter atrophy
Increased signal/ loss of volume of anterior thalamic nucleus
Increased signal/ loss of volume of amygdala
Loss of volume of sibiculum
Loss of grey-white in the anterior temporal lobe
Higher signal on ADC (but may have restricted diffusion following seizure)
Temporal horn dilatation - least sensitive sign
Ipsilateral cerebral hypertrophy
Contralateral cerebellar atrophy

Rememeber:
10% are bilateral, hence comparison with other side is not always useful

MRS:
Decreased NAA
Decreased NAA / Cho ratio
Decreased NAA / Cr ratio
Decreased MI
Increased lipid and lactate soon after as seizure

protocol: CT angiography for GI bleed

2011-12-23T05:36:00.000-08:00

No oral contrast

Section thickness 1 mm
Reconstruction interval 0.8 mm

Unenhanced low dose CT (to show pre-existing intraluminal hyperattenuation)

100–125 mL I.V contrast 4 mL/sec, followed by 50 mL of saline solution at 4 mL/sec

Arterial phase - triggering at proximal abdominal aorta (150 HU)

Portal venous phase at 70 seconds

Reference:
Marti M et al. Acute Lower Intestinal Bleeding: Feasibility and Diagnostic Performance of CT Angiography, January 2012 Radiology, 262, 109-116.

Understanding Intestinal rotation, non-rotation and malrotation

2011-11-09T04:17:00.000-08:00

Nonrotation:

Prone for midgut volvulus

Duodenojejunal junction does not lie inferior and left of SMA

Cecum does not lie in the right lower quadrant.

Incomplete rotation:

Prone for duodenal obstruction, midgut volvulus, internal herniation (right mesocolic i.e. paraduodenal hernia.)

Peritoneal bands from misplaced cecum to mesentery compress D3.

Incomplete fixation:

Mesentery of right and left colon and duodenum do not get fixed retroperitoneally

If descending mesocolon (between IMV & posterior parietal attachment) remains unfixed, small intestine migrates to left upper quadrant = left mesocolic hernia

If the cecum remains unfixed, it may lead to volulus of terminal ileum, cecum, or proximal ascending colon

CT:

Large bowel predominantly on left side and small bowel predominantly on right side

SMA on right and SMV on left, or SMV anterior to SMA

Radiology reporting

2011-09-30T06:22:00.001-07:00

My reporting format

How is the format of my radiology report and why?

2011-09-30T05:41:00.000-07:00

My radiology report slightly deviates from suggested guidelines, and I will try explain it

Radiology 'standard' report format:

Title of examination
History/indication
Technique
Comparison
Findings
Conclusion

The electronic system, which I use, automatically generates the type of examination, date and time of the exam, clinical details given by the clinicians, and the time of signing of the report.

1. Title of the examination:
I do start with the title of the examination, not because of habit or guidelines. Many a times, the details generated by the system is inadequate.

Example 1:

The system generates 'right wrist radiograph', but is not clear whether it is AP and lateral radiograph, or scaphoid views, or views for foreign bodies. So, I start my report with title of the examination, such as 'Right wrist: AP and lateral views'.

Example 2:

The system generates, 'MRI craniofacial', when in fact, TMJ MRI is performed. I have to write my title as 'MRI TMJs'

2. History/ indication:
I usually do not write this in my report as this is electronically generated. However, I do occasionally write history, if there are further details available (either from clinic letters or conversation with the referring team) which would add to my radiological conclusion.

Example:

I would write, 'Further clinical details: I note the patient was diagnosed with carcinoma breast 10 years ago for which she was treated with chemoradiation.'

3. Technique:
I do not write details of the technique in plain radiograph, fluoroscopy and ultrasound.

In CT, I write a brief technical detail.

Example:

In 'CT abdomen and pelvis', I write, non-enhanced CT KUB followed by split dose CT IVU - standard departmental protocol.

In MR, I write all the sequences used. I also mention what sequences were not used, but would have added to the radiological diagnosis.

Example:

In 'MRI brain', I write, 'axial PD and T2 supplemented by sagittal FLAIR and coronal T1 sequences. Please note DWI and ADC mapping was not performed.

If the radiographers have a difficulty in getting the scans right or are unable to perform all sequences, they usually write the details on the request form for the radiologist's attention. I always write 'radiographer's note' soon after the technique, if there is one. This will assist the clinician and reviewing radiologist not to start a blame game.

Example:

'Radiographer's note': Too large patient. Used body coils. Unable to perfom coronal STIR because patient started moving.

4. Comparison
I do not put this as a 'heading'. I usually start my 'Report' with comparison, if available.

Example:

'Comparison is made with the CT dated 1/1/11 and MRI dated 2/2/11' at the beginning of the report.

5. Findings:
I give heading of 'Report' for 'Findings' section.

When I was a radiology resident and registrar, the teaching was to keep radiology description separate from pathological terms. The 'findings' contained clear descriptive radiology terms and signs, avoiding clinical or pathological 'impressions' until one reached the heading of 'conclusion' or 'impression'. This holds good when you are learning the grammer and language of radiology and trying to correlate them clinically.

As we gain more experience, the 'Findings' part of the report will be filled with more of 'impressions' rather than 'radiological discriptions or signs'.

Example 1:

I am yet to see a radiologist who reports, 'A few, thin, band like, linear, nearly horizontal opacities are shown in the both lower zones of the lungs, close to the diaphragms' in 'Findings', and writes, 'Minor atelectasis in both lung bases' in 'Conclusion'. it would be simple to write, 'bibasal atelectasis is noted', not to cause any unnecessary alarm to the clinician.

Example 2:

I would not write the following paragraph to keep my 'Findings' to be 'radiologically descriptive' and to avoid 'clinical conclusion'.

'A large area of homogeneous hyperdensity, measuring 4 x 3 cm, is seen in the right basal ganglion, with mean attenuation of 54 HU. A small area of low attenuation is seen around the hyperdensity. Similar hyperdesnity is seen in the occipital horn of the right lateral ventricle with further hyperdensities in the third and fourth ventricles. The right sylvian fissure is effaced. Overlying gyri and sulci are also effaced. Midline shift is seen, measuring 3 mm to the left. Mild dilatation of the left lateral ventricle is seen'

I would rather write, 'Acute hemorrhage is shown in the right basal ganglia with intraventricular extension, leading to mild dilatation of the left lateral ventricle'.

I think this makes sense to the referring tea.

The above two examples to justify me why I do not use the heading of 'Findings'. 'Findings' heading will contain my clinical impressions also. So I call this 'Findings' heading as 'Report'.

In 'Report', I use descriptive radiology terms only if this has differentials; otherwise, I use clinical/ pathological terms.

Example:

In an elderly person, I would write, 'multiple typical simple cysts are shown in the kidneys', rather than, 'mutliple, rounded, low attenuation lesions of varying sizes are shown in both kidneys with mean attenuation of 3 HU with hardly measurable thin margins'. and then in 'Conclusion', write them again as 'most likely simple cysts'.

I always use present tense, although there are few exceptions during ultrasound and interventions. I start with the most important finding first, write relevant positive findings and then important negative findings.

I give measurement only if it makes sense clinically.

Example:

I would definitely measure the lung cancer, but will not bother to measure renal cysts in the same patient.

I do mention all incidental findings in my report. But I will under play them.

Example 1:

Incidental note is made of a few typical simple cysts in the kidneys.

Example 2:

Note is made of mucosal thickening in the left maxillary sinus.

I try my best to keep my language simple, to use correct medial terminology, and to avoid abbreviations.

6. Conclusion:
I use the heading of 'Comments' for 'Conclusion'. I use 'comment', instead of 'conclusion', because I want the referring clinician to read my 'Report'. Unless he/she reads the report, my 'Comment' section will not make any sense to the referring clinician. I try to keep my 'Report' section as breif as possible and as clinically relevent as possible.

Most of my plain film and ultrasound reports do not have 'Comment' heading. Many of my CT/MR brains, CT of paranasal sinuses, CT petrous, MRI lumbosacral spine and MRI extremities also do not have 'Comment' section.

Examples where I use 'Comment' section:

To answer the clinical question if not done in my 'report',

When my report is too long and contains too many clinically relevant findings.

When I need to combine more than one finding to arrive to a single diagnosis

When I need to advise the clinician regarding further tests

When I need to discuss with the clinician for further clinical details and previous imaging

When I want the case to be reviewed and discussed in the MDT

When I could not arrive to a single diagnosis and want to discuss the differentials in order

When the findings are equivocal or indeterminate, I try to give my reasoning for my clinical conclusion

When the radiological finding does not correlate with the clinical suspicion or diagnosis

I also use 'Comment' section to record my communication with the referring team.

Example:

'The report was faxed to concerned GP surgery'

'I discussed the findings with the on-call surgical registrar'.

Useful links from my blogs:
My other blogs

Diffusion MRI of the brain: Simplified

2010-03-24T06:58:00.000-07:00

Basics:
Bright signal on DWI (B=1000) means restricted diffusion and/or T2 effect.
On ADC, low signal in the same region means restricted diffusion, and bright or isointense signal means T2 shine through effect.
On T2, the same area may appear bright or isointense.

Pathologies with restricted diffusion:
Acute stroke, acute stroke, acute stroke... (repeat this 10 times before proceeding to next)
Infection: Herpes encephalitis, Pyogenic infection, CJD, meningoencephalitis
Epidermoid (ADC usually cannot be calculated)

Diffuse axonal injury
Oxyhemoglobin (intracellular and hyperacute) (extracellular methHb shows increased signal on both DWI and ADC!)
A few acute MS lesions
Post-ictal
Susceptibility artefact: in inferior frontal and temporal regions should not be mistaken for restricted diffusion

Non-restricted diffusion:
Infection: HIV encepahlopathy
Tumor: primary or secondary, arachnoid cyst
Inflammation: most acute MS lesions
Chronic lesions: chronic stroke, gliosis, neuronal loss
Others: hypertensive encephalopathy, clyclosporin toxicity, hyperperfusion after endartertectomy

Sinus thrombosis

2007-10-17T08:53:00.000-07:00

NECT:
Dense Delta sign = dense clot sign - commonly seen in SSS, can be seen in other sinuses too.
Non-arterial infarcts
Dense cortical veins = cord sign
Often a/w hemorrhage
Infarction of basal ganglia and thalami is typical of CVT (this is not a feature of arterial infarct)
Temporal lobe infarct - vein of Labbe thrombosis
Pitfalls:
Hyperdense sign can be normal in infants and neonates, in patients with increased hematocrit (dehydration, polycythemia)
Subdural hemorrhage can mimic CVT and vice versa

CECT:
Empty delta sign, commonly seen in SSS, can be seen in other sinuses too.
Enhancement of falx and tent
Pitfalls:
Intrasinus septa can mimic empty delta sign

MR:
GE images for hemorrhage
Acute: iso on T1, low on T2
Subacute: high on T1 and T2
Chronic: iso on T1 and T2
TOF - short imaging time, beware of artefacts, more false positives, false negative due to methHb
Phase contrast - artefacts due to movements and turbulent flow, no false negative due to methHb
Post-Gd venogram - less false positives, false negative due to methHb or enhancing chronic thrombus
Pitfalls:
Intrasinus septa can mimic CVT
Slow flow may mimic loss of flow void
MethHb may show increased signal on TOF

References:
Poon CS et al. Radiologic Diagnosis of Cerebral Venous Thrombosis. AJR 2007; 189:S76-S78

Pancreatitis: what every radiolgosit should know

2007-10-16T01:54:00.001-07:00

Balthazar severity index:
CT appearance:
Normal - 0 points
Large pancreas - 1 point
Pancreatic/ peripancreatic inflammation - 2
1 fluid collection - 3
> 2 fluid collection - 4
% necrosis:
0 - 0
<> 50% - 6
Score of 0 - no mortality, score 7to10 - 17% mortality

Pancreatitis: what every radiolgosit should know

2007-10-16T01:54:00.000-07:00

Hypothalamic lesions

2007-08-09T15:52:00.000-07:00

Cranipharyngioma - solid and cystic, bimodal, enhance
Germinoma - upper part of infundibulum, solid, enhance, a/w pineal germinoma
Hypothalamic hamartoma - tuber cinerium, solid with cysts, no enhancement, no calcium
Osteolipoma (lipoma) - tuber cinerium, fat and osteoid
Dermoid cyst - midline, fat, no enhancement
Epidermoid cyst - parasellar, CSF signal but high signal on FLAIR, no enhancement
Arachnoid cyst - typical
Rathke's cleft cyst - variable signal, no enhancement, no calcium
Colloid cyst - variable signal, rim may enhance, no calcium
Hypothalamic chiasmatic glioma - solid, enhance
Ganglioglioma - solid with cystic component, nodular or solid enhancement
Choristoma (low grade glioma) - infundibulum, isointense, variable enhancement
Perisellar meningioma - typical
Hemangioblastoma - cyst with enhancing mural nodule, a.w VHL syndrome
Cavernoma - typical
Metastasis - intense enhancement, bone destruction, no sellar enlargement
Lymphoma
Leukemia
Langercells histiocytosis - paediatric, stalk > 3mm, intense enhancement
Hymphocytic infundibuloneurohypophysitis
Sarcoidosis - stalk, a/w leptomeningeal enhancement
Wegener's granulomatosis
Tuberculosis
Syphilis
Encephalitis
Suprasellar pituitary tumour - enhance
Ectopic posterior pituitary
Aneurysm - blood products

Reference:
Saleem SN et al. Lesions of the Hypothalamus: MR Imaging Diagnostic Features. RadioGraphics 2007;27:1087-1108

Virchow Robin spcaes

2007-08-01T03:20:00.000-07:00

VR spaces should have identical signal to CSF on all pulse sequences

3 characteristic locations:
1. Basal ganglia: Along lenticulostriate arteries entering basal ganglia through anterior perforated substance
2. Cerebral white matter: Along the path of perforating medullary arteries as they enter cortical gray matter over the high convexities and extend into the white matter
3. Midbrain:

They can be very large, may cause mass effect,

Differentials:
Lacunar infarct: Deep and non-cortical
PVL: Premature infants
MS
Crytococcus
MPS
Cystic neoplasms
Cysticercosis
Arachnoid cyst
Neuroepithelial cyst

References:
Kwee RM et al. Virchow-Robin Spaces at MR Imaging. RadioGraphics 2007;27:1071-1086

Trauma

2006-12-05T16:33:00.000-08:00

Young person with severe RTA:
CXR AP supine:

Findings:
It is easy to notice rib fractures and ETT in place.
Did you notice difference in the lucency in the lung bases? Which lung base is more lucent? That may be the only sign of pneumothorax!

CT correlation:

Colonic carcinoma

2006-10-27T16:33:00.000-07:00

Dukes staging:

A - Tumour confined to bowel wall
B - Tumor penetrates bowel wall
C - Regional lymphnode involved
D - Distant metastasis

TNM:

T1 - Submucosal involvement
T2 - Muscularis propria involvement
T3 - Beyond muscularis propria
T4 - Peritoneal surface involvement

N1 - up to 3 perirectal/ colic nodes
N2 - 4 or more perirectal/ colic nodes

Azygous fissure

2006-09-25T09:43:00.000-07:00

Images:

Image Gallary

2006-09-17T12:00:00.000-07:00

Chest imaging:
Azygous fissure

Musculoskeletal Imaging

Sarcoidosis

2006-09-17T09:45:00.000-07:00

History:
35 year old CT chest with suspected TB

Mediastinal windows:

Lung windows:

Findings:
Multiple mediastinal nodes in the right paratracheal region. Numerous uniform shaped small lung nodules, deistributed predominantly in the upper and mid zones in the perihilar region with preivascular distribution. No fissural beeding.

Diagnosis:
Sarcoidosis

Discussion:
Differenitals for nodular lung lesions include sarcoidosis, eosinophilic granuloma, miliary tuberculosis and metastasis. Distribution of multiple small nodules in perivascular distribution with irregular thickening of bronchovascular bundles and interlobular septa in upper lobes and associated mediastinal lymphadenopathy strongly indicate sarcoidosis.
The present case is slightly unusual, because there is no fissural beeding and the mediastinal lymphnodes are not large.

References:
Koyama T et al. Radiologic Manifestations of Sarcoidosis in Various Organs. RadioGraphics 2004; 24: 87

GI imaging

2006-09-17T09:28:00.000-07:00

Inflammatory bowel disease:
Crohns disease
Understangin intestinal malrotation

Crohn's disease

2006-09-17T09:08:00.000-07:00

History:
25 year old immegrant with chronic GI symptoms referred from GP for ultrasound

Ultrasound:

Findings:
Multiple thick walled small bowel loops in the left upper abdomen, suggestive of inflammatory bowel disease

Barium follow through:

Findings:
Loong segment narrowing of the jejunal loops with loss of mucosal pattern and bowel wall thickening

Diagnosis:
Crohn's disease

Discussion:
Normal bowel appears as 5 concentric alternate hypo and hyperechoic rings (gut signatue). The average thickness is 2-5mm.
Bowel wall thickening, inflammation of mesenteric fat, mesenteric lymphadenopathy, strictures and fistulas can be seen on US. Bowel wall thickening is usually symmetric with partial or total loss of normal bowel morphology or a 'pseudokidney' sign may be seen. Absence of peristalsis may be observed. The bowel is usually rigid and non-compressible. Angulation may be appreciated. Inflammation of mesentery is seen as echogenic mass (creeping fat). On Doppler, increased blood may be seen, suggestive of active disease. Strictures may be seen as luminal narrowing. Fistula is seen as hypoechoic linear tract with gas bubbles. Transvaginal ultrasound may be used in the diagnosis of rectovaginal and enterovesical fistulas. Inflammatory masses, abscesses are easily demonstrated on ultrasound. Involvement of the urinary bladder is better demonstrated on ultrasound. Presence of free air and bowel obstruction may also be diagnosed on ultrasound.
Ultrasound is 87% sensitive in the diagnosis of crohns disease.

References:
1. Damini N et al. Nongynecologic Applications of Transvaginal US. Radiographics. 1999;19:S179-S200
2. J Sarrazin and SR Wilson. Manifestations of Crohn disease at US. RadioGraphics 1996; 16: 499

Chonalgiocarcinoma

2006-09-17T08:07:00.000-07:00

History:
75 year old lady with features of obstructive jaundice

Unenhanced CT abdomen:

Enhanced CT abdomen:

Findings:
Marked intrahepatic biliary dilatation. A small area of calficiation and surrouding small area of low attenuation in the liver close to the caudate lobe. No extrahepatic biliary dilatation. No other abnormality. Unenhanced CT showed the findings better than the enhanced CT

ERCP:

Findings:
Marked intrahepatic biliary dilataion. A focal area of irregular filling defect in the distal intrahepatic biliary segment

AXR: post percutaneous stenting

Diagnosis:
Intrahepatic cholangiocarcinoma

Discussion:
Calcification in intrahepatic cholangiocarcinoma is usally illdefined, mostly occurs in the periphery of the tumour and is seen in about 20% of patients. Calcifications may also be seen in in biliary cystadenocarcinomas. However, the most common cause of calcified hepatic lesions is inflammatory lesion like granulomatous diseases (TB). Hydatid cysts produce curvilinear or ring calcification. Large hemangiomas may show large central coarse calcffications. Hepatic adenoma may show solitary or multiple calcifications usually eccentric in location. Fibrolamellar carcinoma show calcifications in approximately 20% of cases . Calcfied hepatic metastases are most commonly due to mucin-producing neoplasms (colon carcinoma).
The likely causes for the calcifications in intrahepatic cholangiocarcinomas include central necrosis, mucinous type of cholangiocarcinoma. it is not known if the calcification can predict the prognosis of the disease.
Most of the cholangiocarcinomas are inoperable at the time of presentation and are treated with either ERCP or percutaneous stenting.

References:
1. Lee WJ et al. Radiologic Spectrum of Cholangiocarcinoma: Emphasis on Unusual Manifestations and Differential Diagnoses. RadioGraphics 2001; 21: 97
2. Stoupis C et al. The Rocky liver: radiologic-pathologic correlation of calcified hepatic masses.
RadioGraphics 1998; 18: 675

Omental herniation following penetrating abdominal injury

2006-09-17T07:33:00.000-07:00

History:
35 year old, penetrating abdominal injury

CT:

Findings:
The site of penetrating wound is seen. There is a small pneumoperitoneum. No abdominal organ is injured.

Follow-up:
Managed conservatively in view of no injury to abdominal organs. He presented a month later with persistant pain abdomen

Ultrasound:

Findings:
The panoramic view shows the site of penetrating injury. In addition, there is omental herniation into the abdominal musculature.

Discussion:
Complications of penetrating abdominal injury without associated abdominal visceral injury include wound infection, wound dehiscence, herniation, necrotizing fasciitis and intrabdominal infection. The incidence of omental herniation after penetrating trauma is not documented in the literature, may be because it is not a seriour complication. Interestingly, omentum may be placed to close the penetrating wound, especially in thin individuals and the radiologists should be aware of this while reporting. Abdominal wall herniation are documented even after blunt injuries.

35 year old lady with endometrial carcinoma

2006-09-13T08:53:00.000-07:00

History:
35 year old lady with endometrial carcinoma with back pain- ? bone metastasis

LS spine AP and lateral views:

Findings:
LS spine is normal. Did you notice right basal lung metastasis and surgical clips in the pelvis?

Lesson:
It is important to look at 4 corners of a radiograph.
In all known malignancies look for lunug bases for any metastasis

80 year old lady with weight loss and pain abdomen

2006-09-13T08:48:00.000-07:00

AXR:

Reported as 'scoliosis with lumbosacral degeneration'

One year later, the lady underwent bone scan for backache

Diagnosis:
Paget's disease.

Lesson:
Look at bones carefully in all abdomen radiographs
Paget's is one of the common diseases missed in its early stage on radiograph; apparantly, in most radiographs are the first ones to suggest Paget's disease

ADPKD

2006-09-12T09:35:00.000-07:00

History:
65 year old gentleman with known ADPKD presented with increasing right lumbar pain

Image gallary:

Findings:
ADPKD with hemorrhaic cyst in the right kidney
Did you notice the IVC filter with thrombus at the tip of the IVC filter also?

Discussion:
Flank pain and hematuria may result from cyst hemorrhage or infection, calculi
and renal tumor. There is high association between cyst hemorrhage and flank pain. Differentiation among these complications is important for management purposes. CT is very useful tool in differentiating them.
High density cyst in ADPKD is relatively common finding seen in up to 68% of patients. The larger the size of ADPKD, more the chances of cyst hemorrhage. The factors leading to cyst hemomrhage are possible minor trauma, tight seat belts and spontaneous, possibly related to unsupported sclerotic vessels in the cyst walls. Subcapsular cysts are more likely to bleed.
CT demostrates usually demostrates sharply demarcated homogeneously hyperdense round lesion with smooth margin and no contrast enhancement
They are usually treated by analgeniscs and rest. Sometimes cyst hemorrhage may also cause severe hematunia whihc may need blood transfusion, renal artery embolization and/or nephrectomy.

Reference:
Levine E et al. High-density renal cysts in autosomal dominant polycystic kidney disease demonstrated by CT. Radiology 1985; 154: 477

ANOTHER SIMILAR CASE:
65 year old gentleman with known chronic renal impariment on long term dialysis presented with left flank pain and frank hematuria

Images:

Findings and discussion:
Left upper pole cyst shows increased attenuation, in keeping with cyst hemorrhage. Both kindeys are shrunken and irregular with muleiple cysts, in keeping with chronic renal impairment with long term dialysis. Note the difference in the apeearance of the kindeys in the above case and the present case, although both cases show multiple cysts in both kidneys. The first case is typical for ADPKD and the present one for long term dialysis.

Left ureteric colic

2006-09-05T09:47:00.000-07:00

History:
58 year old gentleman presented with left ureteric colic. CT KUB was requested to exclude ureteric calculus. CT KUB was performed.

Images:

The case was reviewed by the reporting radiologist, before the patient was sent back. The reported radiologist asked for IV contrast enhanced study

Findings:
Mild hydronephrosis of the left kidney with significant perinephric fat stranding. The right renal pelvis and both ureters are also slightly prominant upto the level of the retroperitoneal mass lesion encasing the aorta, IVC and both ureters. No similar masses were found the in the abdomen or pelvis.

Diagnosis:
Retroperitoneal fibrosis

Discussion:
Retroperitoneal fibrosis (RPF) usually presents with a dull aching non-colicky pain in the flank, back, scrotum or lower abdomen. Other symptoms may include fever, ankle edema and DVT. Uncommon presentations include weight loss, nausea, vomiting, anorexia and malaise.
Rarely RPF may present with ureteric colic (as in the present case), Raynaud phenomenon, hematuria, claudication or urinary frequency.

60-70% are idopathic, but can be associated with malignancy, inflammatory processes (Crohn disease, ulcerative colitis, sclerosing cholangitis), trauma, radiation, drugs (methysergide, beta blockers, metyldopa). Steroids are used in the management of the disease.

Asbestosis

2006-08-31T01:12:00.000-07:00

History:
65 year old gentleman with progressive breathlessness

Image gallary:

Findings:
HRCT lung windows: Bilateral basal interstitial lung disease - reticulations, fibrosis, architectural distortion, traction bronchiectasis
HRCT bone windows: Extensive calcified pleural plaques

Diagnosis: Diagnostic of asbestosis

Additional points to be noted/mentioned: Is there associated TB, pleural mass (mesothelioma)or lung mass (bronchogenic carcinoma)?

pelvis AP view

2006-08-30T14:16:00.000-07:00

History:
75 year old woman with left hip pain

Image:

Findings:
It was reported as 'bilateral degenerative changes; otherwise unremarkable'.

The patient came for x-ray 6 months later with worsening left hip pain

Image:

Findings:
Reported as 'Expansile lyic lesion involving the left iliac wing, which needs CT'.

CT:

Findings:
A large lytic expansile agressive lesion involving the left iliac bone. Differentials include expansile metastasis, lymphoma, plasmacytoma or primary bone tumor

Lesson:
1. Grossly, the initial radiograph appears to be normal. But, on careful inspection, one can see the asymmetry in the 'normal' lucenies of the iliac wings. The lucency of the normal right iliac wing is triangular with apex facing downwards with rather striaght margins; where as, the lucency of the abnormal left iliac wing extends more inferiorly and the margins, although fairly well defined, are irregular.
2. In all hip pains, if the hip is normal, look outside the hip for the cause!

Shoulder AP view 02

2006-08-30T09:43:00.000-07:00

History:
66 year old male patient with known matastatic bone lesion presented with right shoulder pain

Image:

Findings:
The reporting registrar reported the film as normal. The consultant took no time to identify the subtle lucency in the humeral head, extending down the shaft and MRI was requested.

MRI:
Confirmed the plain radiograph findings.

Learning points:
1. Always have a high suspecion for metastasis in all elderly or known primary patients.
2. In exam, this film can come without clinical information. Observe the Hickman line first, which gives you a clue that the patient is on chemotherapy or IV antibiotics.

Thoracic imaging

2006-08-16T09:38:00.000-07:00

Chest Radiograph:
Blind spots in CXR

Interstitial lung diseases:
Asbestosis
Sarcoidosis

Blind spots in CXR

2006-08-16T09:31:00.000-07:00

Case 1:
Image gallary:

Did you see both opacities?

Difficulties:
1. The perihilar and periarterial opacities can be easily overlooked even if the lesions may be large. Sometimes the large opacities are not dense and the density may be of that of adjacent/ overlying vessel and are easy to misinterprest as normal variants and ignore them.
2. It is easy to miss the second abnormality, especially when the first one is picked with a great difficulty.

Tips:
1. Be careful about any opacity close to the 'normal' hila and pulmonary artery. There should be no large opacity superior/inferior to the hila, although it is slightly prominant due to lobar arteries and veins.
2. When you picked one abnormality, always search for other abnormalities.

Imaging in women

2006-08-11T15:06:00.000-07:00

Endometrium:
Endometrial carcinoma

Hepatobiliary-Pancreas-Spleen

2006-08-11T14:56:00.000-07:00

Liver:
Tumor:
Cholangiocarcinoma
Interventions:
Image guided liver biopsy

Spleen:
miscellaneous:
Splenic injury

Pancreas:
Pancreatitis: what every radiolgosit should know

Renal trauma

2006-08-11T14:44:00.000-07:00

Kidney is injured in approximately 8%–10% of blunt or penetrating abdominal injuries. Most of the renal trauma is from blunt injuries (80-90%). Serious renal injuries are frequently associated with injuries to other organs. Multiorgan involvement occurs in 80% of patients with serious penetrating trauma and in 75% of those with blunt trauma. A kidney with preexisting abnormality is at increased risk for injury. About 95% of isolated renal injuries are minor and are managed conservatively. Hematuria is seen in 95% of renal injuries, but absence of hematuria does not exclude renal trauma. Hematuria may be absent in severe renal trauma (25% of renal artery thrombosis may not have hematuria). Hematuria with hypotension is associated with increased risk of significant renal injury; but there is poor correlation between severity of hematuria and severity of renal injury. CT has replaced IVU in the investigation of renal trauma. Indications for CT include gross hematuria, microscopic hematuria with shock, microscopic hematuria with positive peritoneal lavage and microscopic hemauria with significant risk of injury to other organs. CT scanning involves 60-80s delayed and 2-5min delayed dual imaging.

Grading (American Association of Surgeons in Trauma)
1: parenchymal contusions, isolated subcapsular hematoma. 82% of renal injuries.
2: superficial cortical lacerations less than 1 cm deep, nonexpanding perirenal hematoma. 6%
3: lacerations greater than 1 cm deep without extension into collecting system or urinary extravasation. (3 & 4 - 7%)
4: Deep lacerations involving collecting system, traumatic thrombosis of segmental renal arterial branch, injury to main renal artery without devascularization
5: shattered kidney, devascularization - renal artery avulsion, main renal artery thrombosis (shearing injury to intima) (4 & 5 - 5%)

Radiological grading:
1: Minor injury: contusion, intrarenal or subcapsular hematoma, minor lacration with limited perirenal hematoma without extension into collecting system or medulla, subsegmental cortical infarct
2: Major: laceration extending from cortex to medulla/collecting system with/without extravasation, segmental infarct
3: Catastrophic: Multiple lacerations, pedicular injury
4: PUJ avulsion

Imaging findings:
On CT, contusions appear as a focal area of low attenuation with or without defined margins. Acute hematomas are of high attenuation. Small subcapsular hematomas are usually cresentic if small or lentiform if large. Laceration appears as a linear low attenuation. Superficials are less than 1cm and deep are more than 1cm deep. When renal capsule is lacerated, perinephric hemorrhage is usually occurs. Active hemorrhage or pseudoaneurysms are seen as intesne enhancing focal areas; active bleed tracks in the centre of surrounding hemorrhage; false aneurysm is round and focal. Active bleeding is a sign of decompensation (38% in one series) and are candidates for embolization. Urine leak is seen in delayed phase (pyelographic phase - 10 minutes later). Infarcts are wedge shaped low attanutaion traingular structures extending from medulla to cortex and do not enhance. Complete devascularization shows absent nephrogram or cortical rim nephrogram. Thrombosis or laceration of the renal vein is a rare and is type of renal pedicle injury.Venography is preffered as CT may not reliably detect venous laceration. Immediate surgical repair of venous injuries may be required to control bleeding. CT may reveal reveal intraluminal thrombus, nephromegaly, a diminished nephrogram, delayed nephrographic progression, and decreased excretion of contrast material into the collecting system, suggestive of acute venous hypertension.

Image Gallary:

Management:
Grade 1 to 4 are managed conservatively. The only absolute surgical indication is life-threatening renal bleeding. Relative indications are presence of extensively devitalized tissue (>50% of parenchyma), uncontrolled urinary extravasation even by ureteral stent or nephrostomy, arterial thrombosis. Urine leak spontaneously resolve in up to 90%. Actively bleeding renovascular pedicle injuries (grade 5) need surgical exploration. Traumatic thrombosis or avulsion of renal artery needs repair within 4 hours with success of 14%–29%. If more than 4 hours with normal contralateral kidney they allow it to atrophy.Early complications occur within 4 weeks and include urinary extravasation and urinoma formation, delayed bleeding, infection of the urinoma, perinephric abscess, sepsis, arteriovenous fistula, pseudoaneurysm and hypertension. Late complications include hydronephrosis, hypertension, calculus formation and chronic pyelonephritis.

References:
1. Fanney DR et al.CT in the diagnosis of renal trauma. RadioGraphics 1990; 10: 29.S201-214
2. Kawashima A et al.Imaging of Renal Trauma: A Comprehensive Review. RadioGraphics 2001; 21: 57

Trauma radiology

2006-08-11T14:41:00.000-07:00

Abdomen:
Spleen
Kidney

splenic injury

2006-08-11T14:33:00.000-07:00

Spleen is most commonly injured solid abdominal organ. Most often due to blunt trauma and often (30-60%) associated with other organ injuries. 25% of left renal injury and 20% of left rib fractures are associated with splenic injury. 40% of splenic lacerations are associated with rib fractures. 20% of splenic injuries occur during surgical procedures. Spontaneous rupture can occur in an abnormal spleen, like in infectious mononucleosus or malaria. Subcapsular hematoma is seen as cresentic/lentiform low attenuation. Parenchymal lacerations are seen as irregularly low attenuation areas. Fracture is seen as complete seperation. Disruption of the capsule causes intraperitoneal hemorrhage. Late complications include splenic pseudocyst.

Grading:
Grade 1 – Minor subcapsular tear or haematoma
Grade 2 – Parenchymal injury not extending to the hilum
Grade 3 – Major parenchymal injury involving vessels and hilum
Grade 4 – Shattered spleen

Management:
Isolated grade 1 and 2 are suitable for conservative management. The patients with cardiovascular instability need surgery, which include repair, spleen conservation surgery (at least 20% of spleen is preserved) and splenectomy. Approximately 30% fail conservative management.

References:
Roberts JL et al. CT in abdominal and pelvic trauma. RadioGraphics 1993; 13: 735

IMAGE GALLARY:

Patient 1:
Splenic contusion, capsular breech with minimal perisplenic lacerations:

Patient underwent splenectomy.

Patient 2:
Large splenic contusion, capsular breech and large perisplenic collection.

Managed conservatively.
Follow-up ultrasound with microbubble shows a small area of infarct

Patient 3: Massive splenic injury

Genitourinary imaging

2006-08-11T14:20:00.000-07:00

Kidneys:
Congenital
ADPKD
Miscellaneous:
Renal Trauma

Scrotum and testis:
Miscellaneous lesions:
Epidermoid cyst

lesson of the week: pancreatic mass

2006-08-10T03:38:00.000-07:00

History:
30 year old gentleman with known bowel carcinoma presented with obstrctive jaundice. On ultrasound there was marked intra and extrahepatic biliary dilatation, but no calculus or obvious mass was demonstrated. CT with pancreatic protocol was requested.

Image gallary:
Arterial phase:

Venous phase:

Obvious imaging findings:
- Marked intra and extra hepatic biliary dilatation
- Pancreatic duct dilatation in the body and tail region
- No obvious mass lesion in the head of the pancreas

Ancillary imaging findings, pointing the diagnosis:
- Encasement of the celiac axis
- Filling defect in the portal and superior mesenteric vein
- Oesophageal varices
- Ascites

Diagnosis:
Pancreatic mass causing marked biliary and pancreatic tree dilatation; encasing the celaic axis; thrombosis of the portal vein and SMV, leading to oesophageal varices and ascitis (portal hypertension)

Lesson:
1. pancreatic and biliary duct dilatation = pancreatic head/ampullary mass. If the mass is not obvious, look for ancillary signs, i.e.,
a. Celiac axis encasement
b. portal vein, SMV or/and splenic vein thrombosis (may be very subtle)
c. signs of portal hypertension
2. Always have a high level of suspision for pancreatic mass lesion.

lesson of the week

2006-08-10T02:59:00.000-07:00

CXR:
Blind spots in CXR
Trauma

AXR:
80 year old lady with weight loss and pain abdomen

LS spine:
35 year old lady with endometrial ca

Extremity radiographs:
Shoulder AP view 01
Shoulder AP view 02

Pelvis and hip radiograph:
Pelvis AP view 01

CT abdomen:
Pancreatic mass

lesson of the week: Shoulder radiograph

2006-08-10T02:42:00.000-07:00

History:
77 year old male patient came to A & E with history of left shoulder pain and mild breathlessness. There was history of fall.

Image gallary:

Imaging findings:
The initial report by the registrar for the shoulder radiograph read 'no fracture or dislocation'. The chest radiograph read 'multiple well defined pleural based lesions, suspecious for pleural metastasis/ mesothelioma. Further clinical correlation required'.

The images were reviewed by the consultant with additional clinical information that the patient was treated for adenocarcinoma of the lung. The 'pleural lesions' lesions were actaully expansile lytic rib lesions, which are also seen on the shoulder AP view. In addition, the lytic lesion seen on both shoulder and chest radiograph was missed by the registrar.

CT was performed to confirm the findings:

Lesson:
It is common to miss many findings on a plain radiograph, especially by registrars.

One should not get carried away from the clincal information (hardly given in most of the cases and may even be misleading).
Always look for malignancies in elderly people

case of the week: abdominal trauma

2006-08-08T19:04:00.000-07:00

History:
25 year old gentleman with bike on car collision admitted with left hypochondrial pain and severe tenderness. The chest x-ray did not show any rib fracture. The blood pressure was stable. Urine showed microscopic haematuria.

Image gallary:

Imaging findings:
1. Left kidney: 2 deep laceration with a large perinephric haemorrhage with haemorrhagic extension into posterior pararenal space. Possible renal vein injury
2. Multiple splenic laceration with small capsular breeches with perisplenic haemorrhage

Discussion:
Splenic injury:
Spleen is most commonly injured solid abdominal organ. Most often due to blunt trauma and often (30-60%) associated with other organ injuries. 25% of left renal injury and 20% of left rib fractures are associated with splenic injury. 40% of splenic lacerations are associated with rib fractures. 20% of splenic injuries occur during surgical procedures. Spontaneous rupture can occur in an abnormal spleen, like in infectious mononucleosus or malaria. Subcapsular hematoma is seen as cresentic/lentiform low attenuation. Parenchymal lacerations are seen as irregularly low attenuation areas. Fracture is seen as complete seperation. Disruption of the capsule causes intraperitoneal hemorrhage. Late complications include splenic pseudocyst.
Grading:
Grade 1 – Minor subcapsular tear or haematoma
Grade 2 – Parenchymal injury not extending to the hilum
Grade 3 – Major parenchymal injury involving vessels and hilum
Grade 4 – Shattered spleen
Management:
Isolated grade 1 and 2 are suitable for conservative management. The patients with cardiovascular instability need surgery, which include repair, spleen conservation surgery (at least 20% of spleen is preserved) and splenectomy. Approximately 30% fail conservative management.

Renal trauma:
Kidney is injured in approximately 8%–10% of blunt or penetrating abdominal injuries. Most of the renal trauma is from blunt injuries (80-90%). Serious renal injuries are frequently associated with injuries to other organs. Multiorgan involvement occurs in 80% of patients with serious penetrating trauma and in 75% of those with blunt trauma. A kidney with preexisting abnormality is at increased risk for injury. About 95% of isolated renal injuries are minor and are managed conservatively. Hematuria is seen in 95% of renal injuries, but absence of hematuria does not exclude renal trauma. Hematuria may be absent in severe renal trauma (25% of renal artery thrombosis may not have hematuria). Hematuria with hypotension is associated with increased risk of significant renal injury; but there is poor correlation between severity of hematuria and severity of renal injury. CT has replaced IVU in the investigation of renal trauma. Indications for CT include gross hematuria, microscopic hematuria with shock, microscopic hematuria with positive peritoneal lavage and microscopic hemauria with significant risk of injury to other organs. CT scanning involves 60-80s delayed and 2-5min delayed dual imaging.
Grading (American Association of Surgeons in Trauma)
1: parenchymal contusions, isolated subcapsular hematoma. 82% of renal injuries.
2: superficial cortical lacerations less than 1 cm deep, nonexpanding perirenal hematoma. 6%
3: lacerations greater than 1 cm deep without extension into collecting system or urinary extravasation. (3 & 4 - 7%)
4: Deep lacerations involving collecting system, traumatic thrombosis of segmental renal arterial branch, injury to main renal artery without devascularization
5: shattered kidney, devascularization - renal artery avulsion, main renal artery thrombosis (shearing injury to intima) (4 & 5 - 5%)
Radiological grading:
1: Minor injury: contusion, intrarenal or subcapsular hematoma, minor lacration with limited perirenal hematoma without extension into collecting system or medulla, subsegmental cortical infarct
2: Major: laceration extending from cortex to medulla/collecting system with/without extravasation, segmental infarct
3: Catastrophic: Multiple lacerations, pedicular injury
4: PUJ avulsion
Imaging findings:
On CT, contusions appear as a focal area of low attenuation with or without defined margins. Acute hematomas are of high attenuation. Small subcapsular hematomas are usually cresentic if small or lentiform if large. Laceration appears as a linear low attenuation. Superficials are less than 1cm and deep are more than 1cm deep. When renal capsule is lacerated, perinephric hemorrhage is usually occurs. Active hemorrhage or pseudoaneurysms are seen as intesne enhancing focal areas; active bleed tracks in the centre of surrounding hemorrhage; false aneurysm is round and focal. Active bleeding is a sign of decompensation (38% in one series) and are candidates for embolization. Urine leak is seen in delayed phase (pyelographic phase - 10 minutes later). Infarcts are wedge shaped low attanutaion traingular structures extending from medulla to cortex and do not enhance. Complete devascularization shows absent nephrogram or cortical rim nephrogram. Thrombosis or laceration of the renal vein is a rare and is type of renal pedicle injury.Venography is preffered as CT may not reliably detect venous laceration. Immediate surgical repair of venous injuries may be required to control bleeding. CT may reveal reveal intraluminal thrombus, nephromegaly, a diminished nephrogram, delayed nephrographic progression, and decreased excretion of contrast material into the collecting system, suggestive of acute venous hypertension.
Management:
Grade 1 to 4 are managed conservatively. The only absolute surgical indication is life-threatening renal bleeding. Relative indications are presence of extensively devitalized tissue (>50% of parenchyma), uncontrolled urinary extravasation even by ureteral stent or nephrostomy, arterial thrombosis. Urine leak spontaneously resolve in up to 90%. Actively bleeding renovascular pedicle injuries (grade 5) need surgical exploration. Traumatic thrombosis or avulsion of renal artery needs repair within 4 hours with success of 14%–29%. If more than 4 hours with normal contralateral kidney they allow it to atrophy.
Early complications occur within 4 weeks and include urinary extravasation and urinoma formation, delayed bleeding, infection of the urinoma, perinephric abscess, sepsis, arteriovenous fistula, pseudoaneurysm and hypertension. Late complications include hydronephrosis, hypertension, calculus formation and chronic pyelonephritis.

References:
1. Fanney DR et al.CT in the diagnosis of renal trauma. RadioGraphics 1990; 10: 29.S201-214
2. Kawashima A et al.Imaging of Renal Trauma: A Comprehensive Review. RadioGraphics 2001; 21: 57
3. Roberts JL et al. CT in abdominal and pelvic trauma. RadioGraphics 1993; 13: 735

case of the week

2006-07-31T11:31:00.000-07:00

Musculoskeletal:

Respiratory system:
Asbestosis
Sarcoidosis

Hepatobiliary:
Cholangiocarcinoma

GIT:
Crohns disease

Genitourinary:
ADPKD
Left ureteric colic
Epidermoid cyst of the testis

Trauma:
Blunt abdominal trauma
Penetrating abdominal injury

case of the week: epidermoid cyst of the testis

2006-07-31T06:17:00.000-07:00

History:
20 year old gentleman was GP-referred for ultrasound for a palpable lump in the left testis or
epididymis. The swelling was not painful, but of some discomfort.

Image Gallary:

Imaging findings:
Ultrasound showed a solitary 2cm well defined round heterogenous echogenic mass in the inferior pole of the left testis. It showed rings of hypo- and hyper-echogenicities or 'onion-ring' appearance. On Doppler, there was no increased blood flow in or around the lesion. The mass was not related to the mediastinum of the testis. The epididymis was normal. The right testis and epididymis had normal appearances. There was no hydrocele or varicocele. The abdominal ultrasound showed no enlarged para-aortic lymphnodes. Based on the ultrasonic appearances, the presumptive diagnosis of the epidermoid cyst was made and further referral to the urologist was suggested (follow-up will be updated)

Discussion:
Epidermoid cyst is a rare benign lesion of the testis (1%–2% of testicular lesions). Commonly the patients present between 2nd and 4th decades. Most of the epidermoid cysts are single and unilateral. Multiple or bilateral cysts are associated with Gardner syndrome, Klinefelter syndrome and cryptorchid testes. They are filled with laminated cheesy material. The clinical management is controversial and recently, organ-preserving surgery has been favored over traditional orchidectomy.

Most patients present with painless mass, but a few complain of pain or discomfort. US may show an echogenic centre surrounded by a hypoechoic ring and hyperechogenic rim, causing 'bull’s-eye' or 'target' lesion; or alternating hypoechoic and hyperechoic concentric rings, causing 'onion skin appearance'. The lesions are not vascular.

MR shows low signal peripheral rim on both T1- and T2-weighted images and a circumferential high signal zone surrounding a low-signal central zone, or alternating concentric rings of low and high signal on T1- and T2-weighted images. On contrast, there is no enhancement.

The central echogenic center may represent keratin debris and the concentric layeers may represent lipid and water containing materials. The squamous cell capsule causes hyperechoic rim.

The 'onion ring' appearance is charecteristic for an epidermoid cyst, although not pathognomonic. Simple and tunica albuginea cysts are anechoic. Tumors, abscesses and chronic inflammatory processes may have capsule, but are likely to show hypervascularity. Neoplasms usually enhance on Gd-enhanced MR. Hemorrhage may have heterogenous appearance on ultrasound.

References:
1. Cho JH et al. Sonographic and MR Imaging Findings of Testicular Epidermoid Cysts. AJR 2002; 178:743-748
2. Loya AG et al. Epidermoid Cyst of the Testis: Radiologic-Pathologic Correlation. RadioGraphics 2004; 24: S243-S246.
3. Woodward PJ et al. From the Archives of the AFIP: Tumors and Tumorlike Lesions of the Testis: Radiologic-Pathologic Correlation. RadioGraphics 2002; 22: 189.

Cancer staging

2006-07-11T15:47:00.000-07:00

Gynaecology:
Endometrial carcinoma

GIT:
Colonic carcinoma

Neuroradiology

2006-07-11T15:45:00.000-07:00

Vascular:
Sinus thrombosis

Miscellaneous:
Virchow Robin spcaes

Differential Diagnosis:
Differentials for intraventricular lesions

Interventional Radiology

2006-07-11T15:42:00.000-07:00

Hepatobiliary:
Radiological guided liver biopsy

Staging: Endometrial cancer

2006-07-06T15:24:00.000-07:00

TNM/ FIGO staging of endometrial cancer:
I - T1: confined to corpus. IA-T1a - endometrium. IB-T1b - less than 1/2 of myometrium. Stage IC - T1C - more than 1/2 myometrium

II - T2: cervical extension. IIA-T2a - endocervical glandular. IIB-T2b - cervical stroma

III - T3: local +/- regional spread. IIIA-T3a - serosa/adnexa/peritoneal cytology. IIIB-T3b - vagina. IIIC-regional LN.

IVA - T4: mucosa of bladder/bowel involvement. IVB - Distant metastasis

Lymphnode drainage:
Mid and lower to parametrium, paracervical and obturator nodes - inguinal
Upper and fundus to iliac and para-aortic.

Neuroradiology: Differentials: Intraventricular lesions

2006-07-05T03:54:00.000-07:00

Choroid plexus papilloma: rough-irregular surface, atriaof the lateral ventricles, children less than 10 years, homogenous marked enhancement

Meningioma: calcification common, trigone of lateral ventricle, not close to septum pellucidum, strong enhancement, older women

Astrocytoma: calcium +/-, peritumoral edema

Ependymoma: fourth ventricle, peritumoral brain invasion, childhood

Subependymoma: fifth decade, no enhancement

Central neurocytoma: 2-3 decade, lateral ventrcle with 3rd ventricle extension, attaches to septum pellucium, some enhencement, no peritumoral edema or brain invasion, calcium common

Gaint cell astrocytoma: in tuberous sclerosis, at lateral-third ventricle junction

Oligodendroglioma: rare, calcium, brain invasion,

Reference: Zhang et al. Central neurocytoma: clinical, pathological and neuroradiological findings. Clin Rad (2006): 61: 348-357 .

Interventional Radiology: Image Guided Liver Biopsy

2006-07-04T11:52:00.000-07:00

Lesions not to be biopsied

Focal liver lesions that can be characterised by imaging do not need biopsy confirmation if strictly adhered to certain diagnostic criteria: Haemangioma, Simple cysts, Focal fatty infiltration, Focal fatty sparing.

Situations where the benefit of accepting a non-tissue diagnosis (based on imaging, clinical setting and serum markers) outweighs the risk of biopsy: HCC in a patient with chronic liver disease.

Always search for other more safely accessible sites for biopsy: suspected disseminated disease, tuberculosis, sarcoidosis, malignancy and lymphoma, open biopsy of a significant axillary, supraclavicular or cervical node is always both safer and more reliable than a guided liver biopsy in terms of accurate histology.

ULTRASOUND GUIDED LIVER BIOPSY

Relative contraindications

Coagulopathy - If the lesion is one that cannot be accurately characterised by imaging and if no other more easily accessible site for biopsy is available (i.e. significant axillary, supraclavicular or upper deep cervical neck nodes), hepatic biopsies can be performed safely in patients with coagulopathy after correction with appropriate clotting elements. Large bore needles are not recommended.

Ascites - is not a contraindication to percutaneous liver biopsy. Few studies, which have addressed the safety of performing a liver biopsy in patients with cirrhosis in the presence of ascites, have reported low complication rates.4. Biliary Obstruction - In patients with obstructive jaundice large bore needles (19 gauge or larger) should be avoided.

Coagulopathy assessment

Prothrombin time (PT), partial thromboplastin time (PTT) and platelet count should be obtained prior to biopsy.

When the platelet count is less than 100,000/ml, PT is prolonged by > 3 seconds relative to the control and PTT is prolonged by > 6 relative to control the biopsy, if absolutely necessary, is done after administration of the appropriate clotting elements.

When the coagulopathy is severe in patients with diffuse liver disease, transjugular biopsy is performed.

Anaesthesia:

Mild sedative is given prior to the procedure

Choice of Modality for Image Guidance

Ultrasound guidance is modality of choice whenever the lesion can be seen by ultrasound imaging. Real time guidance during needle placement is helpful in avoiding major portal and hepatic veins.

CT is preferred during drainage tube insertion in the superior segments to avoid transgression of the pleural space.

Needle Selection

Diffuse liver disease, hepatic lymphoma, most focal liver lesions or a hepatic transplant, a large core 18-gauge Tru-Cut needle biopsy is required; theoretically, needles upto 14 gauge can be used.

For lesions coursing through major vessels or bowel, for vascular lesions and in the presence of coagulopathy a non-cutting needle small bore needle such as a Chiba 20-gauge needle should be used.

Technique

Free hand technique or attached needle guide technique.

Lateral or anterolateral, intercostal or sub costal for the right lobe

Anterior for the left lobe.

Biopsy to be performed during suspended respiration.

Always interpose a cuff of normal parenchyma between the liver capsule and the margin of a lesion.

Complications

0.83 % complication rate for fine needles and 1.44% for larger cutting needles.

Minor complications include transient localized discomfort, post procedure pain sufficient to require analgesia, mild transient hypotension.

Major complications include hypotension.

Post Procedure Care

Since symptoms related to significant post biopsy haemorrhage is noted within 3 hours after the procedure the patient has to be monitored during this time.

Accuracy

61% to 100%.

Lower accuracy rates have been obtained with fine-needle aspiration

TRANSJUGULAR LIVER BIOPSY

Indications

Presence of massive ascites

Presence of massive obesity

Severe coagulopathy

Failed percutaneous biopsy

Suspected vascular tumour or peliosis hepatis

Need for ancillary vascular procedures (TIPS, venography)

Contraindications

No major contraindications.

Thrombosis of the internal jugular vein - relative contraindication.

Anaesthesia

Uncooperative and paediatric patients may require anaesthesia.

The procedure is performed under mild sedation. ECG monitors the heart rate and rhythm throughout the procedure, this being important as the right atrium is traversed.

Method

Fasted for four hours.

Supine position with the foot end of the table elevated to distend the jugular vein and also prevent air embolism.

Jugular vein is imaged with high frequency ultrasound, which also helps to define the relation of the carotid artery to the jugular vein.

9 French sheath is introduced into the right jugular vein using the Seldinger technique.

A multipurpose catheter is used to cannulate the right hepatic vein.

A deep inspiration decreasing the angulation of the right hepatic vein with the IVC, improves cannulation.

Hepatic venography is optional and can be done if there is a suspicion of Budd Chiari syndrome.

Over a guide wire introduced into the hepatic vein a metallic introducer is inserted. The metallic cannula has an outer polyurethane sheath. The biopsy needle is introduced through this metallic cannula. The needle should be pointed anteriorly while cutting the tissue.

It is important to do biopsy during suspended respiration.

Since the needle exits the hepatic vein into the liver parenchyma and then cuts the tissue, any bleeding is usually into the venous system.

Care should be taken not to introduce the needle too far into the hepatic vein to avoid traversing the capsule.

The metallic needle is left in place to repeat the biopsy and take more tissue for culture / dry weight copper etc.

The angulation of the right hepatic vein with the IVC might be acute and hinder access with the metallic cannula.

Post Procedure Care :

After removal of the needle and sheath the patient should be nursed in the sitting position for 4 hours. This keeps the jugular vein collapsed and prevents puncture site haematoma formation. The abdominal girth and vital parameters are monitored to check for haemorrhage.

Complications

Perforation of the liver capsule (3.5%)

Intraperitoneal haemorrhage (0.5%)

Transient cardiac arrhythmias

Transient hoarseness or Horner's syndrome caused by local anaesthetic

Haematoma at the puncture site

Puncture of the internal carotid artery

Success Rate

64 to 100% of cases

Aspiration biopsy is 68%

Trucut biopsy is 97%

Reference:

L Raghuram et al. Image guided liver biopsy.Bombay Hospital Journal.Volume 44 No.4, October 2002.