Opportunistic screening for osteoporosis in abdominal computed tomography for Chinese population.

This study assessed the possibility of diagnosing and excluding osteoporosis with routine abdominal CT scans in a Chinese population who underwent both DXA and CT for unrelated reasons. Statistical correlation was made between the HU measured of the spine on CT and various parameters on DXA. Diagnostic cutoff points in terms of HU were established for the diagnosis (≤ 136 HU) and exclusion (≥ 175 HU) of osteoporosis on sagittal reformatted images. There was excellent positive and negative predictive value for the DXA-defined diagnostic subgroups and were also comparable with previous studies in Caucasian populations. The authors exhort radiologists to report these incidental findings to facilitate early detection and treatment of osteoporosis in unsuspecting patients to prevent fractures and related complications. PURPOSE: The suspicion for osteoporosis can be raised in diagnostic computed tomography of the abdomen performed for other indications. We derived cutoff thresholds for the attenuation value of the lumbar spinal vertebrae (L1-5) in Hounsfield units (HU) in a Chinese patient population to facilitate implementation of opportunistic screening in radiologists. METHODS: We included 109 Chinese patients who concomitantly underwent abdominal CT and dual X-ray absorptiometry (DXA) within 6 months between July 2014 and July 2017 at a university hospital in Hong Kong. Images were retrospectively reviewed on sagittal reformats, and region-of-interest (ROI) markers were placed on the anterior portion of each of the L1-L5 vertebra to measure the HU. The mean values of CT HU were then compared with the bone mineral density (BMD) and T-score obtained by DXA. Receiver operator characteristic (ROC) curves were generated to determine diagnostic cutoff thresholds and their sensitivity and specificity values. RESULTS: The mean CT HU differed significantly (p < 0.01) for the three DXA-defined BMD categories of osteoporosis (97 HU), of osteopenia (135 HU), and of normal individuals (230 HU). There was good correlation between the mean CT HU and BMD and T-score (Pearson coefficient of 0.62 and 0.61, respectively, p < 0.001). The optimal cutoff point for exclusion of osteoporosis or osteopenia was HU ≥ 175 with negative predictive value as 98.9% and with area under curve (AUC) of ROC curve as 0.97. The optimal cutoff point for diagnosis of osteoporosis was HU ≤ 136 with positive predictive value as 81.2% and with AUC of ROC curve as 0.86. CONCLUSION: This is the first study on osteoporosis diagnosis with routine CT abdominal scans in Chinese population. The cutoff values were comparable with previous studies in Caucasian populations suggesting generalizability. Radiologists should consider routinely reporting these opportunistic findings to facilitate early detection and treatment of osteoporosis to prevent fractures and related complications.

Percutaneous cholecystostomy for high-risk patients with acute cholangitis.

Percutaneous cholecystostomy (PC) is a well-established treatment for acute cholecystitis. We investigate the performance and role of PC in managing acute cholangitis.Retrospective review on all patients who underwent PC for acute cholangitis between January 2012 and June 2017 at a major regional hospital in Hong Kong.Thirty-two patients were included. The median age was 84 years and median American Society of Anaesthesiologists (ASA) physical status was Class III (severe systemic disease). All fulfilled Tokyo Guidelines 2013 (TG13) diagnostic criteria for moderate or severe cholangitis. Eighty-four percent of the patients were shown to have lower common bile duct stones on imaging. The majority had previously failed intervention by endoscopic retrograde cholangiopancreatography (38%), percutaneous transhepatic biliary drainage (38%), or both (13%)The technical success rate for PC was 100% with no procedure-related mortality. The overall 30-day mortality was 9%. Rest of the patients (91%) had significant improvement in clinical symptoms and could be discharged with median length of stay of 14 days. Significant postprocedural biochemical improvement was observed in terms of white cell count (P < .001), serum bilirubin (P < .001), alkaline phosphatase (P = .001), and alanine transaminase levels (P < .001). Time from admission to PC was associated with excess mortality (P = .002).PC is an effective treatment for acute cholangitis in high-risk elderly patients. Early intervention is associated with lower mortality. PC is particularly valuable as a temporising measure before definitive treatment in critical patients or as salvage therapy where other methods endoscopic retrograde cholangiopancreatography/percutaneous transhepatic biliary drainage (ERCP/PTBD) have failed.

Denervation pseudohypertrophy of calf muscles associated with diabetic neuropathy.

Denervation of muscle usually leads to muscle atrophy with fatty replacement but, uncommonly, also results in muscle hypertrophy or pseudohypertrophy with fatty replacement. We report the ultrasonographic and magnetic resonance imaging (MRI) findings of a patient with diffuse fatty infiltration of calf muscles as a result of denervation pseudohypertrophy. The elevated fasting glucose, neurogenic electromyographic changes, and muscle atrophy with adipose tissue infiltration are consistent with diabetic neuropathy as the cause of denervation pseudohypertrophy. Lumbosacral radiculopathy and plexopathy were excluded by MRI. The imaging features reported in the literature are reviewed. The important differential diagnosis of infiltrating lipoma and denervation hypertrophy, as well as other causes of monomelic hypertrophy or swelling, is discussed. This case report demonstrates the importance of MRI, with clinical, biochemical, electrophysiological, and histologic correlation in the diagnosis of denervation pseudohypertrophy. Correct diagnosis of denervation pseudohypertrophy has an important role in guiding further investigations and treatment of the disease and the underlying cause.

Spinal epidural extramedullary haematopoiesis in ß-thalassaemia intermedia.

A 22-year-old man known to have ß-thalassaemia intermedia since childhood presented with bilateral lower limb weakness after spinal anaesthesia for an elective minor operation of his left leg. MRI and CT scans were performed to rule out acute epidural haematoma; coincidental imaging features of marrow hyperplasia and spinal epidural extramedullary haematopoiesis were found. This article will present and discuss the imaging features, differential diagnosis, management and literature review of the rare occurrence of extramedullary haematopoiesis in the spinal epidural space.