A review of split-bolus single-pass CT in the assessment of trauma patients.

PURPOSE: The purpose of this study was to review and compare the image quality and radiation dose of split-bolus single-pass computed tomography(CT) in the assessment of trauma patients in comparison to standard multi-phase CT techniques. METHODS: An online electronic database was searched using the MESH terms "split-bolus," "dual phase," and "single pass." Inclusion criteria required the research article to compare a split contrast bolus protocol in a single-pass scan in the assessment of trauma patients. Studies using split-bolus CT technique in non-traumatic injury assessment were excluded. Six articles met the inclusion criteria. CONCLUSIONS: Parenchymal and vascular image qualities, as well as subjective image quality assessments, were equal or superior in comparison to non-split-bolus multi-phase trauma CT protocols. Split-bolus single-pass CT decreased radiation exposure in all studies. Further research is required to determine the superior split-bolus protocol and the specificity and sensitivity of detecting blunt cerebrovascular injury screening, splenic parenchymal vascular lesions, and characterization of pelvic vascular extravasation.

Pachymeningeal enhancement-a comprehensive review of literature.

Pachymeningeal enhancement, synonymous with dural enhancement, is a radiological feature best appreciated on a contrast-enhanced magnetic resonance imaging (MRI). The vasculature of the dura mater is permeable, facilitating avid uptake of contrast agent and subsequent enhancement. Thin, discontinuous enhancement can be normal, seen in half the normal population. In patients complaining of postural headaches worse on sitting, gadolinium-enhanced MRI findings of diffuse pachymeningeal enhancement is highly suggestive of benign intracranial hypotension. In these cases, the process of pachymeningeal enhancement is explained by the Monro-Kellie doctrine as compensatory volume changes by vasocongestion and interstitial oedema of the dura mater due to decreased cerebrospinal fluid (CSF) pressure. Focal and diffuse pachymeningeal enhancement can also be attributed to infectious or inflammatory, neoplastic and iatrogenic aetiologies. Correction of the underlying pathology often results in spontaneous resolution of the pachymeningeal enhancement. There have also been reports of pachymeningeal enhancement associated with cerebral venous sinus thrombosis, temporal arteritis, baroreceptor reflex failure syndrome and arteriovenous fistulae.

Automatic classification of distal radius fracture using a two-stage ensemble deep learning framework.

Distal radius fractures (DRFs) are one of the most common types of wrist fracture and can be subdivided into intra- and extra-articular fractures. Compared with extra-articular DRFs which spare the joint surface, intra-articular DRFs extend to the articular surface and can be more difficult to treat. Identification of articular involvement can provide valuable information about the characteristics of fracture patterns. In this study, a two-stage ensemble deep learning framework was proposed to differentiate intra- and extra-articular DRFs automatically on posteroanterior (PA) view wrist X-rays. The framework firstly detects the distal radius region of interest (ROI) using an ensemble model of YOLOv5 networks, which imitates the clinicians' search pattern of zooming in on relevant regions to assess abnormalities. Secondly, an ensemble model of EfficientNet-B3 networks classifies the fractures in the detected ROIs into intra- and extra-articular. The framework achieved an area under the receiver operating characteristic curve of 0.82, an accuracy of 0.81, a true positive rate of 0.83 and a false positive rate of 0.27 (specificity of 0.73) for differentiating intra- from extra-articular DRFs. This study has demonstrated the potential in automatic DRF characterization using deep learning on clinically acquired wrist radiographs and can serve as a baseline for further research in incorporating multi-view information for fracture classification.

Virtual non-contrast detector-based spectral CT predictably overestimates tissue density for the characterisation of adrenal lesions compared to true non-contrast CT.

PURPOSE: To establish if virtual non-contrast (VNC) images generated from contrast-enhanced detector-based spectral CT could replace true non-contrast (TNC) imaging for the characterisation of adrenal masses. METHODS: TNC and VNC images were retrospectively reviewed for 39 patients with one or more adrenal lesions who underwent contrast-enhanced spectral CT of the upper abdomen. Lesions were categorised as either 'adenoma' or 'indeterminate/other lesion' based on current reference standards. The CT density of each lesion was measured on both image sets by two readers and compared using Wilcoxon signed-rank test. ROC analysis with Youden's J index method was performed to determine the optimal attenuation cut-off for diagnosing benign adenoma on VNC images. RESULTS: Forty-four lesions were included, 37 of which were diagnosed as adenomas. There were significant differences between TNC and VNC measurements for both readers (mean difference 9.1 HU for reader 1; 9.8 HU for reader 2; p < 0.01). Optimal attenuation thresholds for diagnosing adenomas on VNC were 25.3 HU (reader 1) and 23.9 HU (reader 2) for the entire population, and 18.3 HU (reader 1) and 19.7 HU (reader 2) for lipid-rich adenomas < 10 HU on TNC imaging. CONCLUSION: There is insufficient evidence to support the use of VNC as a substitute for TNC images in the characterisation of adrenal lesions. VNC using a detector-based spectral CT scanner shows a predictable increase in attenuation values compared to TNC. Thus, future studies might be better directed towards finding a new threshold value for diagnosing benign adrenal adenomas on VNC imaging.

Common bile duct polyp mimicking choledocholithiasis: a case report with laparoscopic transcystic management.

Although polyps of the extrahepatic biliary system are rare, an awareness of their potential existence is important as they may closely mimic choledocholithiasis clinically and radiologically but require distinct measures for successful management. This report describes the presentation and successful laparoscopic transcystic management of this infrequently encountered condition. It also explores the literature and discovers the numerous potential presenting features of common bile duct calculi and the spectrum of possible management options.

Early repeat computed tomographic imaging in transferred trauma and neurosurgical patients: Incidence, indications and impact.

INTRODUCTION: Computed tomographic (CT) imaging is widely available in Australian rural and remote hospitals and is often performed prior to patient transfer to definitive tertiary hospital care. We hypothesised that critically ill trauma and neurosurgical patients might have CT scans repeated after interhospital transfer and that the utility of this practice might be low in relation to the additional financial cost and radiation exposure. METHODS: We conducted a retrospective review of clinical records to determine the proportion of trauma and neurosurgical patients transferred to our tertiary ICU from other hospitals between 1 June 2013 and 30 June 2014 who underwent a repeat CT scan. The additional effective radiation dose was estimated using the dose length product method and the Australian Medicare Benefits Schedule was used to estimate the associated cost. RESULTS: Of the 247 patients transferred for trauma and neurosurgical indications, many (144; 58%) had undergone CT imaging at the referring hospital. Repeat scans were performed in 60 (42%) already imaged patients (24% of all transferred patients), most frequently for changed clinical indications. While in 11 (18%) of those 60 already imaged patients the repeat scan led to an identifiable change in management, for another 13 (22%) patients the repeat scans appeared to be potentially avoidable. The median cost of a repeat scan was AU$250 and the median additional effective radiation dose was 2.74 mSv per patient. CONCLUSION: Repeat CT scans for patients already imaged prior to transfer were relatively common, occurring mostly for apparently valid clinical reasons. However, the additional radiation risk and financial cost of these repeat scans appeared on retrospective audit to be potentially avoidable in approximately one in five cases.

Migration of eroded laparoscopic adjustable gastric band causing small bowel obstruction and perforation.

We present an unusual and rare complication caused by gastric band erosion into the stomach after band placement 15 years ago. The complication was only picked up after the band had subsequently migrated from the stomach at the site of erosion, to the distal ileum causing acute small bowel obstruction and focal perforation requiring emergency laparotomy.Abdominal pain in patients with gastric band should always be treated as serious until proven otherwise.

Is there a need for routine follow-up after primary total hip arthroplasty?

BACKGROUND: The objective of routine outpatient assessment of well-functioning patients after primary total hip arthroplasty (THA) is to detect asymptomatic failure of prostheses to guide recommendations for early intervention. We have observed that the revision of THAs in asymptomatic patients is highly uncommon. We therefore question the need for routine follow-up of patients after THA. METHODS: A prospective analysis of an orthopaedic database identified 158 patients who received 177 revision THAs over a four-year period. A retrospective chart review was conducted. Patient demographics, primary and revision surgery parameters and follow-up information were recorded and cross-referenced with Australian Orthopaedic Association National Joint Replacement Registry data. RESULTS: One hundred ten THAs in 104 patients (average age 70.4 (SD 9.8 years)). There were 70 (63.6%) in total, 13 (11.8%) femoral and 27 (24.5%) acetabular revisions. The indications for revision were aseptic loosening (70%), dislocation (8.2%), peri-prosthetic fracture (7.3%), osteolysis (6.4%) and infection (4.5%). Only four (3.6%) were asymptomatic revisions. A mean of 5.3 (SD 5.2 and 1.9 (SD 5.3)) follow-up appointments were required before revision in patients with and without symptoms, respectively. The average time from the primary to revision surgery was 11.8 (SD 7.23) years. CONCLUSIONS: We conclude that patients with prostheses with excellent long-term clinical results as validated by joint registries, routine follow-up of asymptomatic THA should be questioned and requires further investigation. Based on the work of this study, the current practice of routine follow-up of asymptomatic THA may be excessively costly and unnecessary, and a less resource-intensive review method may be more appropriate.