Defining Normal Reference Range For The Cross Sectional Area Of The Median Nerve At The Wrist And Forearm Using High-Resolution Ultrasonography In Asymptomatic Pakistani Adults.

BACKGROUND: Carpal tunnel syndrome (CTS) can be diagnosed easily on ultrasonography (USG); which is a cheap, non-invasive and readily available modality. However, there is wide normal variation in the normal values of cross-sectional area (CSA) of median nerve among different populations; therefore, its necessary to establish a normal range of variability in median nerve dimensions in different populations. METHODS: A total of 500 asymptomatic patients i.e., 1000 median nerves were evaluated at the distal wrist crease and mid-forearm by 3 expert radiologists independently. All patients having a positive nerve conduction study or history of carpal tunnel syndrome and wrist trauma were excluded. Ultrasound was performed with a 7.5-15 MHz high-frequency linear probe. SPSS v 20 was used to analyze data. RESULTS: The study population had a mean age of 31.40±10.11 years with a female-to-male ratio of 1.36:1. Mean BMI was 22.15±4.34 Kg/m2 . The mean cross section area of the median nerve at the right wrist was calculated to be 6.8±1.96 mm2 and the left wrist was 6.6±1.96 mm2 . The mean median nerve cross-section area at the right mid-forearm was 5.3±1.46 mm2 and the left mid-forearm was 5.2±1.50 mm2 . A decrease in mean median nerve cross-section areas was noted by moving from wrist to forearm. Similarly, males showed higher median nerve CSA than females. CONCLUSIONS: Mean median nerve cross-section area was found to be different from Western countries. This warrants the utilization of the data of the Pakistani population to establish our own normal reference range for median nerve cross-sectional area to avoid misdiagnoses.

Segment IV hepatic artery in potential donors for living related liver transplantation: Evaluation with multi-detector CT.

OBJECTIVE: To assess segment IV hepatic arterial anatomy and its variation on multi-detector computed tomography in potential liver donors. METHODS: The retrospective study was conducted at Shifa International Hospital, Islamabad and comprised data of potential liver transplant donors related to the period between January 2012 and June 2017. Computed tomography scans were performed using multi-detector scanners. Images were transferred to work station for postprocessing and were analysed regarding the origination and variation of the arteries by two independent experienced radiologists. RESULTS: Of the 455 patients whose records were evaluated, 299(65.7%) were males and 156(34.3%) were females. Six types of segment IV artery were defined based on their points of origin: left hepatic artery 285(62.6%), right hepatic artery 111(24.4 %), proper hepatic artery 9(1.8 %), common hepatic artery 29(6.4%), gastro duodenal artery 3(0.7 %), and dual 18(4.1 %).313 of total cases (68.8%) had normal anatomy with no variation. Those with aberrant/variant anatomy constituted 142(31.2%) of the total. CONCLUSIONS: Multi-detector computed tomography angiography was found to be a fast, reliable and non-invasive technique that could evaluate normal as well as anatomical variants of segment IV arteries.