Classification of paediatric brain tumours by diffusion weighted imaging and machine learning.

To determine if apparent diffusion coefficients (ADC) can discriminate between posterior fossa brain tumours on a multicentre basis. A total of 124 paediatric patients with posterior fossa tumours (including 55 Medulloblastomas, 36 Pilocytic Astrocytomas and 26 Ependymomas) were scanned using diffusion weighted imaging across 12 different hospitals using a total of 18 different scanners. Apparent diffusion coefficient maps were produced and histogram data was extracted from tumour regions of interest. Total histograms and histogram metrics (mean, variance, skew, kurtosis and 10th, 20th and 50th quantiles) were used as data input for classifiers with accuracy determined by tenfold cross validation. Mean ADC values from the tumour regions of interest differed between tumour types, (ANOVA P < 0.001). A cut off value for mean ADC between Ependymomas and Medulloblastomas was found to be of 0.984 × 10-3 mm2 s-1 with sensitivity 80.8% and specificity 80.0%. Overall classification for the ADC histogram metrics were 85% using Naïve Bayes and 84% for Random Forest classifiers. The most commonly occurring posterior fossa paediatric brain tumours can be classified using Apparent Diffusion Coefficient histogram values to a high accuracy on a multicentre basis.

Fifteen-Year Single-Center Experience of Biliary Complications in Liver Trauma Patients: Changes in the Management of Posttraumatic Bile Leak.

INTRODUCTION: Management of posttraumatic bile leak has evolved over time in our unit, from endoscopic retrograde cholangiopancreatography (ERCP) stenting to intraperitoneal drainage (IPD) alone as first-line treatment for intraperitoneal bile leak. MATERIALS AND METHODS: Retrospective review of liver trauma patients from 2002 to 2017. Demographics, time and mode of diagnosis of bile leak, management, and outcome were analyzed of the box plot. RESULTS: In 118 patients, there were 28 traumatic bile leaks. Eighteen were free intraperitoneal and 10 were localized bilomas. The median time of diagnosis was 6 days following injury. The modes of diagnosis were preemptive hepatobiliary scintigraphy (18), computed tomography (CT) or ultrasound (7), and laparotomy (3). Free intraperitoneal biliary leak management included 11 IPD alone, 3 IPD plus ERCP, 2 IPD plus transcystic biliary stent (TBS), 1 operative cholangiogram, and 1 no intervention. Median time of IPD duration was 7 days (4-95) in IPD alone versus 14 days (6-40) in IPD + ERCP/TBS (p = 0.3). Median inpatient length of stay was 13 days (8-44) in IPD alone versus 12 days (8-22) in IPD + ERCP/TBS (p = 0.4). CONCLUSION: Placement of IPD alone, as first-line treatment, is safe and effective in the management of intraperitoneal bile leaks, avoiding the costs and potential complications of ERCP.

Morphology of vascular ring arch anomalies influences prognosis and management.

OBJECTIVE: This study aimed to explore the anatomical features of aortic arch anomalies associated with vascular rings, hoping to identify those which may increase the risk of symptomatic presentation and surgical intervention. METHODS: This was a retrospective observational study at a single cardiac unit. Individuals diagnosed with an aortic arch anomaly, either isolated or non-isolated, between June 2014 and September 2018 were included. The morphology of the aortic arch was established via analysis of postnatal echocardiography, CT or MRI scans. CT and magnetic resonance studies were evaluated for the presence of a Kommerell diverticulum in those with aberrant vessels. Case notes were reviewed for relevant clinical data. RESULTS: Of those with aberrant subclavian arteries, 24/79 (30.4%) were shown to have a Kommerell diverticulum. Additional forms of congenital heart disease were present in 133/227 (58.6%) individuals. Surgical division of the vascular ring was performed in 30/227 (13.2%), most commonly in the setting of a double aortic arch (70.8%). In those with aberrant subclavian arteries, no children without a Kommerell diverticulum were referred for surgery. In those with a Kommerell diverticulum confirmed on imaging, 11/24 underwent surgery. CONCLUSION: Individuals with a double aortic arch, or an aberrant subclavian artery arising from a Kommerell diverticulum, have the highest requirement for surgical intervention, especially in isolated anomalies. These individuals should remain under monitoring. The subjective nature of symptoms remains problematic. Longitudinal research is required further to understand the natural history of vascular rings and how it links to morphology.

Diagnostic accuracy and added value of qualitative radiological review of 1H-magnetic resonance spectroscopy in evaluation of childhood brain tumors.

BACKGROUND: 1H-magnetic resonance spectroscopy (MRS) facilitates noninvasive diagnosis of pediatric brain tumors by providing metabolite profiles. Prospective studies of diagnostic accuracy and comparisons with conventional MRI are lacking. We aimed to evaluate diagnostic accuracy of MRS for childhood brain tumors and determine added clinical value compared with conventional MRI. METHODS: Children presenting to a tertiary pediatric center with brain lesions from December 2015 through 2017 were included. MRI and single-voxel MRS were acquired on 52 tumors and sequentially interpreted by 3 radiologists, blinded to histopathology. Proportions of correct diagnoses and interrater agreement at each stage were compared. Cases were reviewed to determine added value of qualitative radiological review of MRS through increased certainty of correct diagnosis, reduced number of differentials, or diagnosis following spectroscopist evaluation. Final diagnosis was agreed by the tumor board at study end. RESULTS: Radiologists' principal MRI diagnosis was correct in 69%, increasing to 77% with MRS. MRI + MRS resulted in significantly more additional correct diagnoses than MRI alone (P = .035). There was a significant increase in interrater agreement when correct with MRS (P = .046). Added value following radiologist interpretation of MRS occurred in 73% of cases, increasing to 83% with additional spectroscopist review. First histopathological diagnosis was available a median of 9.5 days following imaging, with 25% of all patients managed without conclusive histopathology. CONCLUSIONS: MRS can improve the accuracy of noninvasive diagnosis of pediatric brain tumors and add value in the diagnostic pathway. Incorporation into practice has the potential to facilitate early diagnosis, guide treatment planning, and improve patient care.

A comparison of pseudo-continuous arterial spin labelling and dynamic susceptibility contrast MRI with and without contrast agent leakage correction in paediatric brain tumours.

OBJECTIVE:: To investigate correlations between MRI perfusion metrics measured by dynamic susceptibility contrast and arterial spin labelling in paediatric brain tumours. METHODS:: 15 paediatric patients with brain tumours were scanned prospectively using pseudo-continuous arterial spin labelling (ASL) and dynamic susceptibility contrast (DSC-) MRI with a pre-bolus to minimise contrast agent leakage. Cerebral blood flow (CBF) maps were produced using ASL. Cerebral blood volume (CBV) maps with and without contrast agent leakage correction using the Boxerman technique and the leakage parameter, K2, were produced from the DSC data. Correlations between the metrics produced were investigated. RESULTS:: Histology resulted in the following diagnoses: pilocytic astrocytoma (n = 7), glioblastoma (n = 1), medulloblastoma (n = 1), rosette-forming glioneuronal tumour of fourth ventricle (n = 1), atypical choroid plexus papilloma (n = 1) and pilomyxoid astrocytoma (n = 1). Three patients had a non-invasive diagnosis of low-grade glioma. DSC CBV maps of T1-enhancing tumours were difficult to interpret without the leakage correction. CBV values obtained with and without leakage correction were significantly different (p < 0.01). A significant positive correlation was observed between ASL CBF and DSC CBV (r = 0.516, p = 0.049) which became stronger when leakage correction was applied (r = 0.728, p = 0.002). K2 values were variable across the group (mean = 0.35, range = -0.49 to 0.64). CONCLUSION:: CBV values from DSC obtained with and without leakage correction were significantly different. Large increases in CBV were observed following leakage correction in highly T1-enhancing tumours. DSC and ASL perfusion metrics were found to correlate significantly in a range of paediatric brain tumours. A stronger relationship between DSC and ASL was seen when leakage correction was applied to the DSC data. Leakage correction should be applied when analysing DSC data in enhancing paediatric brain tumours. ADVANCES IN KNOWLEDGE:: We have shown that leakage correction should be applied when investigating enhancing paediatric brain tumours using DSC-MRI. A stronger correlation was found between CBF derived from ASL and CBV derived from DSC when a leakage correction was employed.

Is the faculty of family planning and reproductive health care guidance on emergency contraception being followed in general practice? An audit in the West Midlands, UK.

BACKGROUND AND METHODOLOGY: In 2003, the Faculty of Family Planning and Reproductive Health Care (FFPRHC) of the Royal College of Obstetricians and Gynaecologists published guidance on emergency contraception (EC). A literature search revealed no published work describing doctors' actions when prescribing EC. In order to assess the extent to which the FFPRHC Guidance is being followed in general practice, an audit of the medical notes of women requesting EC between January 2003 and December 2004 in six general practice surgeries located in the West Midlands, UK was conducted. From the medical notes, discussions between health care professionals and patients requesting EC regarding ongoing contraceptive needs, the risk of sexually transmitted infections (STIs) and the availability of the emergency intrauterine device (IUD) were recorded. RESULTS: A total of 718 emergency contraceptive pill consultations were analysed. The median age for presentation was 24 years. The 20-24 years age group accounted for the most consultations (30.9%). In 40% of consultations there was no evidence of future contraceptive needs having been discussed. Only 20 (2.8%) consultation notes contained evidence that STIs had been discussed. Chlamydia tests were undertaken in only 15/718 (1.7%) consultations. In only 10 (1.4%) of the consultations was the IUD discussed with the patient as an alternative form of EC. DISCUSSION AND CONCLUSIONS: This audit suggests that the FFPRHC Guidance on EC is not being followed in general practice, and therefore patients requesting EC may not be receiving the highest standard of care.