Kumble Seetharama Madhusudhan

Respiratory-Triggered Versus Breath-Hold Diffusion-Weighted MRI of Liver Lesions: Comparison of Image Quality and Apparent Diffusion Coefficient Values

OBJECTIVE The purpose of our study was to compare respiratory-triggered and breath-hold diffusion-weighted liver MRI and to assess the agreement in the apparent diffusion co-efficient (ADC) values between the two sequences. MATERIALS AND METHODS Forty-eight patients (27 men, 21 women; mean age, 45.2 years) with focal liver lesions underwent respiratory-triggered and breath-hold diffusion-weighted MRI (DWI) in addition to routine MRI. Both sequences had identical imaging parameters except for signal averages, which were 6 in respiratory-triggered and 2 in breath-hold sequences. A total of 92 lesions (maximum of three lesions per patient; 37 benign, 55 malignant) were evaluated. Lesions were confirmed by typical imaging appearance, histopathology, or follow-up. Signal-to-noise ratio (SNR) of the liver, contrast-to-noise ratio (CNR), and relative contrast ratio of the lesions were measured in each DWI sequence and were statistically compared using the Mann-Whitney U test. The ADC values of normal liver and each category of liver lesions in the two sequences were compared for agreement using Pearsons coefficient and reliability analysis scale. RESULTS The SNR of the normal liver was significantly better on respiratory-triggered DWI than on breath-hold DWI. The mean CNR of metastases, hepatocellular carcinomas, and abscesses was significantly better in the respiratory-triggered DWI than in the breath-hold DWI sequences. The ADC values of liver and focal lesions measured by the two techniques showed good agreement. The SDs of the ADC values of normal liver were similar in the two sequences. CONCLUSION Respiratory-triggered DWI should be preferred over breath-hold DWI for the evaluation of focal liver lesions because it provides better image quality and SNR without any compromise in the calculated ADC values.

Endovascular Embolization of Pulmonary Sequestration in an Adult

Angio-Seal set was then deployed. The intravascular component was positioned as usual in the common femoral artery as an anchor while the collagen plug was intended to be deployed in the neck of the pseudoaneurysm. The procedure technique is diagramed in the Figure. US showed immediate closure of the pseudoaneurysm. Follow-up US scans obtained 1 day, 7 days, 1 month, 2 months, and 12 months after the procedure demonstrated successful closure without further recurrence. The formation and recurrence of the pseudoaneurysms might be related to severe calcification in the femoral arteries that may inhibit the healing of vascular wall after intubation. Thrombin injection induced thrombosis and temporary discontinued blood flow in the cavity of pseudoaneurysm but had no effect on the healing process of vascular wall. If the crevasse did not heal in time, impulse of blood pressure in femoral artery might break through a new tunnel and lead to recurrence of pseudoaneurysm. Although the pseudoaneurysm of the right femoral artery was successfully sealed with a covered stent, it was not suitable for the left femoral pseudoaneurysm due to lack of available vascular approach and the probability of inducing a new pseudoaneurysm. Embolization was also not suitable for the same reason. Surgical repair would have been a reasonable choice but was refused by the patient. This case provided a new approach using a closure device to close a femoral pseudoaneurysm when thrombin injection failed. In addition to Angio-Seal, the only available vascular closure device in the hospital, other vascular closure devices such as Perclose (Abbott Laboratories, Abbott Park, Illinois) might also be considered. The incidence of pseudoaneurysm is approximately 1% in endovascular procedures (1), whereas the failure rate of US- guided thrombin injection has been reported to be 4%–9% (2,3). Therefore, this technique of deploying a closure device to close a pseudoaneurysm may be considered in 0.05% of patients undergoing endovascular procedures.

Endovascular Embolization of Visceral Artery Pseudoaneurysms Using Modified Injection Technique with N-Butyl Cyanoacrylate Glue.

PURPOSE To evaluate the indications, feasibility, safety, and effectiveness of N-butyl cyanoacrylate (NBCA) with modified injection technique in embolization of visceral artery pseudoaneurysms (PSAs). MATERIALS AND METHODS A retrospective evaluation was performed of 31 patients (26 men, 5 women; mean age, 32.6 y) with visceral artery PSAs that were treated with embolization using NBCA with modified sequential injection and flushing technique. The most common indication for using NBCA was preservation of a major feeding artery (n = 18), followed by difficult catheterization secondary to arterial tortuosity (n = 5), failed previous coil embolization (n = 4), and short landing zone for coils (n = 4). NBCA alone was used in 25 patients, and NBCA with coils was used in 6 patients. The patients were followed clinically until discharge and 1 and 3 months after discharge. RESULTS The mean amount of NBCA-ethiodized oil (Lipiodol; Guerbet LLC, Villepinte, France) mixture injected was 0.24 mL (range, 0.1-1.1 mL). Embolization with NBCA was technically successful in all (100%) patients. Recurrence was seen in 3 (9.7%; 2--splenic artery; 1--left gastric artery) patients after a mean time of 16.3 days (range, 10-27 d) of initial embolization resulting in clinical success of 90.3%. All 3 patients underwent successful repeat embolization with secondary technical success rate of 100%. Minor (pain) and major (nontarget embolization in 2; microcatheter adhesion and fracture in 1) complications were seen in 3 patients each. CONCLUSIONS NBCA is a safe and effective embolization agent when injected with modified technique in treatment of visceral artery PSAs.

Imaging and interventions in hilar cholangiocarcinoma: A review

Hilar cholangiocarcinoma is a common malignant tumor of the biliary tree. It has poor prognosis with very low 5-year survival rates. Various imaging modalities are available for detection and staging of the hilar cholangiocarcinoma. Although ultrasonography is the initial investigation of choice, imaging with contrast enhanced computed tomography scan or magnetic resonance imaging is needed prior to management. Surgery is curative wherever possible. Radiological interventions play a role in operable patients in the form of biliary drainage and/or portal vein embolization. In inoperable cases, palliative interventions include biliary drainage, biliary stenting and intra-biliary palliative treatment techniques. Complete knowledge of application of various imaging modalities available and about the possible radiological interventions is important for a radiologist to play a critical role in appropriate management of such patients.We review the various imaging techniques and appearances of hilar cholangiocarcinoma and the possible radiological interventions.

Schwannoma of both intrahepatic and extrahepatic bile ducts: a rare case

Schwannoma of the biliary tree is extremely uncommon, with only a few cases having been reported so far. They commonly present with obstructive jaundice. Although involvement of the extrahepatic duct is common, occurrence in the intrahepatic ducts has not been reported. We report a case of combined intrahepatic and extrahepatic schwannoma in a 46-year-old man presenting with obstructive jaundice.

Accuracy of computed tomographic features in differentiating intestinal tuberculosis from Crohn's disease: a systematic review with meta-analysis

Abdominal computed tomography (CT) can noninvasively image the entire gastrointestinal tract and assess extraintestinal features that are important in differentiating Crohns disease (CD) and intestinal tuberculosis (ITB). The present meta-analysis pooled the results of all studies on the role of CT abdomen in differentiating between CD and ITB. We searched PubMed and Embase for all publications in English that analyzed the features differentiating between CD and ITB on abdominal CT. The features included comb sign, necrotic lymph nodes, asymmetric bowel wall thickening, skip lesions, fibrofatty proliferation, mural stratification, ileocaecal area, long segment, and left colonic involvements. Sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio (DOR) were calculated for all the features. Symmetric receiver operating characteristic curve was plotted for features present in >3 studies. Heterogeneity and publication bias was assessed and sensitivity analysis was performed by excluding studies that compared features on conventional abdominal CT instead of CT enterography (CTE). We included 6 studies (4 CTE, 1 conventional abdominal CT, and 1 CTE+conventional abdominal CT) involving 417 and 195 patients with CD and ITB, respectively. Necrotic lymph nodes had the highest diagnostic accuracy (sensitivity, 23%; specificity, 100%; DOR, 30.2) for ITB diagnosis, and comb sign (sensitivity, 82%; specificity, 81%; DOR, 21.5) followed by skip lesions (sensitivity, 86%; specificity, 74%; DOR, 16.5) had the highest diagnostic accuracy for CD diagnosis. On sensitivity analysis, the diagnostic accuracy of other features excluding asymmetric bowel wall thickening remained similar. Necrotic lymph nodes and comb sign on abdominal CT had the best diagnostic accuracy in differentiating CD and ITB.

Cavernous sinus thrombophlebitis causing reversible narrowing of internal carotid artery

Neurology India | Jan-Feb 2009 | Vol 57 | Issue 1 Figure 2: Axial contrast-enhanced T1W MRI (a) shows diffuse enhancement of the wall of the right intra-petrous ICA (arrow). Ethmoid and sphenoid sinusitis is also seen. 3D contrast-enhanced MR angiogram (b) shows long segment narrowing of the right ICA (arrow). The left ICA is normal (black arrow) Cavernous sinus thrombophlebitis causing reversible narrowing of internal carotid artery

Esophageal lichen planus: a case report and review of literature.

Lichen planus is a rare cause of esophagitis and esophageal stricture. It is invariably associated with oral mucosal involvement and the diagnosis has to be considered in these patients who present with dysphagia. We present a case of esophageal stricture secondary to lichen planus.

Development and validation of visceral fat quantification as a surrogate marker for differentiation of Crohn's disease and Intestinal tuberculosis.

Crohns disease (CD) and intestinal tuberculosis (ITB) have close phenotypic resemblance. Mesenteric fat (a component of visceral fat [VF]) hypertrophy and fat wrapping, which is visible radiologically as fibrofatty proliferation, is seen more commonly in CD than in ITB.

Intestinal tuberculosis versus crohn's disease: Clinical and radiological recommendations.

Intestinal tuberculosis is a common clinical problem in India. The clinical features of this disease are nonspecific and can be very similar to Crohns disease. Radiological evaluation of the small bowel has undergone a paradigm shift in the last decade. This long tubular organ that has traditionally been difficult to evaluate can now be well-visualized by some innovative imaging and endoscopic techniques. This article highlights the state-of-the-art evaluation of ulceroconstrictive diseases of the bowel and provides recommendations for the differentiation of intestinal tuberculosis from Crohns disease.