Acoustic radiation force impulse imaging of pancreas in patients with early onset idiopathic recurrent acute pancreatitis.

BACKGROUND AND AIMS: Patients with recurrent acute pancreatitis (RAP) may progress to chronic pancreatitis (CP). A critical step in this progression is the development of fibrosis. Elastography has been used to assess degree of fibrosis by measurement of shear wave velocity (SWV). The aim of this study was to measure the stiffness of pancreas as a surrogate for pancreatic fibrosis in patients with RAP and compare it with a group of individuals without any history of pancreatic disorders. MATERIAL AND METHODS: Using acoustic radiation force impulse (ARFI) imaging SWV was calculated in 31 patients with idiopathic RAP having disease onset ≤30 years. A control group of 31 individuals with no history pancreatic disorder and no features of CP on endosonography was selected for comparison. ARFI imaging was done by a single radiologist who was blinded to the cases and controls RESULTS:: Mean age of patients with RAP was 24.8 (SD 9.86) years, disease duration was 3.45 (interquartile range 1-5) years, mean number of episodes 4.9 (SD 2.72). There was a significant difference in SWV between patients (1.27 ± 0.50 m/s) and controls (1.00 ± 0.17 m/s) (P = 0.001)). There was a positive correlation between SWV and number of pain episodes (P = 0.026) and negative correlation with BMI (P = 0.002). CONCLUSION: SWV was high in patients with RAP indicating a stiff pancreas. The stiffness increases with the number of episodes of pancreatitis.

Computed Tomography Evaluation of the Arterial Supply to Segment 4 of the Liver.

INTRODUCTION: In a setting of living-donor liver transplant and patients undergoing extended hepatic resections for both primary and metastatic liver tumors, preoperative assessment of hepatic arterial anatomy is very important because of the risk of ischemic complications in the event of inadvertent injury to the arterial supply. Anatomical variations in hepatic arterial supply to the liver are very common and seen in nearly half the population. Identifying anomalous origin of segment 4 hepatic artery is vital since this vessel can cross the transection plane and can result in liver ischemia and liver failure. The purpose of our study is to study the variations in hepatic arterial anatomy to segment 4 of the liver in the Indian population. MATERIALS AND METHODS: A retrospective evaluation of 637 consecutive computed tomography (CT) angiograms over a period of 1 year was performed, and we analyzed the arterial supply to segment 4 of the liver. RESULTS: We found that the arterial supply to segment 4 of the liver originated from left hepatic artery (LHA) in majority of cases, 76.3%. LHA along with the accessory LHA supplied this segment in 6.4%, whereas the accessory LHA solely supplied this segment in 0.4%. The right hepatic artery (RHA) was seen to supply this segment in 10.2%. Dual supply with branches from the RHA and LHA was seen in 6.6% of patients. CONCLUSION: Preoperative mapping of segment 4 hepatic arterial supply using CT angiography will act as a roadmap to surgeons as they attempt to carefully dissect and preserve this segments' arterial supply. Depending on the anatomical variation, surgical techniques will vary to ensure safety of segment 4 arterial supply.

Congenital bronchopulmonary vascular malformations, "sequestration" and beyond.

Congenital bronchopulmonary vascular malformations (BPVMs) include a broad spectrum of disorders that involve abnormalities in the form of disruptions of normal communication and/or presence of abnormal communication between one or more of the three main systems of the lung, namely, the airways, arteries, and veins. The establishment of abnormal communications by means of small openings or anastomoses is termed as malinosculation. The aim of this pictorial essay is to illustrate the imaging appearances of the various types of pulmonary malinosculation.

Atypical ultrasound features of parathyroid tumours may bear a relationship to their clinical and biochemical presentation.

OBJECTIVES: To describe atypical ultrasound features of parathyroid lesions and correlate them with clinical presentation and histopathology. MATERIALS AND METHODS: Retrospective review of 264 patients with primary hyperparathyroidism who underwent ultrasound imaging prior to parathyroidectomy was performed. Patients with atypical ultrasound findings (n = 26) were identified; imaging findings were correlated with clinical presentation and histopathology. RESULTS: Twenty-one (80 %) lesions were adenomas, two (8 %) were adenomas with cellular atypia, and three (11.5 %) were carcinomas. Seventeen (65 %) lesions showed cystic change; five (19 %) of them had >50 % cystic change. These lesions were adenomas with cystic degeneration. Cystic degeneration had significant positive correlation with the lesion size and PTH level, but cystic adenomas correlated negatively with lesion weight. Six (23 %) lesions were isoechoic and one (4 %) was hyperechoic; histology predominantly revealed haemorrhage, hyalinisation and fibrosis; one lesion showed fat deposition and another had multiple granulomas within the adenoma. Twenty (83 %) lesions had heterogeneous echotexture and showed combinations of acinar dilatation, necrosis, haemorrhage and fibrosis. Heterogeneous lesions tended to be significantly larger and heavier, and they were associated with higher PTH levels. Four (15 %) lesions had calcifications. Scintigraphy was concordant in 22 (96 %), n = 23. One scintigraphy-negative lesion was a cystic parathyroid adenoma. CONCLUSION: Atypical ultrasound features of parathyroid lesions pose a diagnostic challenge. Awareness of these features would help improve lesion detection. TEACHING POINTS: 1. Cystic change is significantly related to the size, weight and measured parathyroid hormone levels. 2. Cystic change in parathyroid tumours indicated a slightly higher risk of malignancy. 3. Heterogeneous parathyroid adenomas are larger in size and heavier, and they have higher PTH levels. 4. Awareness of atypical ultrasound features will improve preoperative clinical prediction.