Artificial intelligence for detection of intracranial haemorrhage on head computed tomography scans: diagnostic accuracy in Hong Kong.

INTRODUCTION: The use of artificial intelligence (AI) to identify acute intracranial haemorrhage (ICH) on computed tomography (CT) scans may facilitate initial imaging interpretation in the accident and emergency department. However, AI model construction requires a large amount of annotated data for training, and validation with real-world data has been limited. We developed an algorithm using an open-access dataset of CT slices, then assessed its utility in clinical practice by validating its performance on CT scans from our institution. METHODS: Using a publicly available international dataset of >750 000 expert-labelled CT slices, we developed an AI model which determines ICH probability for each CT scan and nominates five potential ICH-positive CT slices for review. We validated the model using retrospective data from 1372 non-contrast head CT scans (84 [6.1%] with ICH) collected at our institution. RESULTS: The model achieved an area under the curve of 0.842 (95% confidence interval=0.791-0.894; P<0.001) for scan-based detection of ICH. A pre-specified probability threshold of ≥50% for the presence of ICH yielded 78.6% accuracy, 73% sensitivity, 79% specificity, 18.6% positive predictive value, and 97.8% negative predictive value. There were 62 true-positive scans and 22 false-negative scans, which could be reduced to six false-negative scans by manual review of model-nominated CT slices. CONCLUSION: Our model exhibited good accuracy in the CT scan-based detection of ICH, considering the low prevalence of ICH in Hong Kong. Model refinement to allow direct localisation of ICH will facilitate the use of AI solutions in clinical practice.

CT analysis of the posterior anatomical landmarks of the scoliotic spine.

AIM: To use computed tomography (CT) to assess the validity and reliability of the posterior landmarks, spinous processes (SP), transverse processes (TP), and centre of lamina (COL), as compared to the Cobb angle to assess the curve severity and progression of adolescent idiopathic scoliosis (AIS). MATERIALS AND METHODS: A consecutive series of CT examinations of severe AIS patients were included retrospectively. SP, TP, and COL angles were measured for all curves and compared to the Cobb angle. RESULTS: One hundred and five patients were included. The mean Cobb versus SP, TP, and COL angles were, 54° versus 37°, 49°, and 51° in the thoracic curves and 34° versus 26°, 31°, and 34° in the (thoraco)lumbar curves. Intraclass correlation coefficient values for intra-rater measurements of the SP, TP, and COL angles were 0.93, 0.97, and 0.95 and 0.70, 0.90, and 0.88 for inter-rater measurements. The correlations between the Cobb angle and SP, TP, and COL angles in thoracic and (thoraco)lumbar curves were 0.79 and 0.66, 0.87 and 0.84, and 0.80 and 0.70. CONCLUSIONS: The posterior spinal landmarks can be used for assessment of scoliosis severity in AIS; however, they show a systematic underestimation, but a strong correlation with the coronal Cobb angle. TP and COL angles had the highest validity.

Dietitian-led lifestyle modification programme for obese Chinese adolescents with non-alcoholic fatty liver disease: a randomized controlled study.

BACKGROUND: The prevalence of non-alcoholic fatty liver disease (NAFLD) in children is increasing. This study evaluated the efficacy of a dietitian-led lifestyle modification programme (D-LMP) to reduce NAFLD in obese adolescents. METHODS: Subjects with intra-hepatic triglyceride content (IHTC) equal to or greater than 5% diagnosed by proton-magnetic resonance spectroscopy (1H-MRS) were enroled and randomly assigned to either the D-LMP intervention or conventional paediatrician-led consultation (P-CON) group. Subjects in the P-CON group received usual care consisting of a consultation by a paediatrician with the child and parents every 16 weeks. Intention-to-treat analysis was used for data analysis. RESULTS: Fifty-two subjects were recruited, with 26 in each group. After the initiation phase (at week-16), there was a greater difference in the change in the IHTC and BMI z-score in the D-LMP group (P = 0.029 and <0.001, respectively) and there was a decrease in dietary intake of fat content (P = 0.019). After 52 weeks of the maintenance phase, both groups had reductions of IHTC to 2-3% and there was no intergroup difference in the rate of reduction. During the maintenance phase, parents' involvement was minimal in the D-LMP group, with only three parents accompanying their children to attend the dietitian sessions. In contrast, over 90% of the parents in the P-CON group regularly accompanied their children to attend the consultations suggesting the possibility that regular parental and paediatrician involvement may contribute to increasing awareness on fatty liver complications. Multivariate analysis showed that only reduction in body fat remained as an independent factor associated with remission of NAFLD at the end of both study phases. CONCLUSIONS: A dietitian-led lifestyle modification intervention reduced IHTC, BMI z-score and body fat in obese Chinese adolescents with NAFLD. To sustain the effect of this intervention, regular parental and paediatrician involvement may be important.

Operational definitions improve reliability of the age-related white matter changes scale.

BACKGROUND AND PURPOSE: Although the age-related white matter changes (ARWMC) scale has been advocated to be applicable to both MRI and CT for assessing the severity of WMC, its inter-rater reliability on CT is only fair. We aimed to operationalize the ARWMC scale and investigate the effect of this operationalization on the reliability and validity on MRI and CT. METHODS: Operational definitions of the ARWMC scale were derived from Erkinjuntti research criteria for subcortical vascular dementia and Scheltens scale. Using original and operationalized ARWMC scale, eight observers recorded the time for rating per MRI and per CT. We investigated the inter-rater and intrarater reliability as well as validity against volume using data from 97 stroke patients. RESULTS: Inter-rater reliability of the operationalized scale on CT (0.874, 95% confidence interval [0.780-0.934]) was better than the original scale (0.569, 95% confidence interval [0.247-0.775]). Its intrarater reliability on CT (0.869) and reliability on MRI (inter-rater: 0.860; intrarater: 0.838) was comparable with the original scale (CT intrarater: 0.750 and on MRI inter-rater: 0.845; intrarater: 0.853). The time required to administer the operationalized scale (4'2″ for MRI and 1'18″ for CT) was similar to that of the original scale (3'56″ for MRI and 1'16″ for CT). The original scale and operationalized scale also significantly correlated with WMC volume (operationalized scale ρ = 0.613, P < 0.001, original scale ρ = 0.638, P < 0.001). CONCLUSION: Operational definitions improve the inter-rater reliability of ARWMC scale on CT, and it correlates with volumetric measurement.

Cerebral microbleeds and quality of life in acute ischemic stroke.

This study evaluated the impact of cerebral microbleeds (CMBs) on the health-related quality of life (HRQoL) in 458 Chinese patients with first or recurrent acute ischemic stroke. HRQoL was assessed with the Short Form-36 (SF-36). Univariate analysis showed the presence of lobar CMBs to be negatively correlated with patients' physical functioning (PF; p < 0.01), social function (SF; p < 0.01), and role-emotional (RE; p < 0.05) scores. Subsequent linear regression analysis revealed lobar CMBs to be independently associated with the PF and SF scores (p < 0.05). The limitations of this study include the exclusion of patients with more severe stroke, the lack of longitudinal assessments, the use of a generic rather than stroke-specific HRQoL scale, and the less than optimal sensitivity of the CMB measurement. The study findings suggest that CMBs have a significant impact on the HRQoL of stroke survivors.

Personalized prediction of transcranial magnetic stimulation clinical response in patients with treatment-refractory depression using neuroimaging biomarkers and machine learning.

BACKGROUND: Functional connectivity between the left dorsolateral prefrontal cortex (DLPFC) and subgenual cingulate (sgACC) may serve as a biomarker for transcranial magnetic stimulation (rTMS) treatment response. The first aim was to establish whether this finding is veridical or artifactually induced by the pre-processing method. Furthermore, alternative biomarkers were identified and the clinical utility for personalized medicine was examined. METHODS: Resting-state fMRI data were collected in medication-refractory depressed patients (n = 70, 16 males) before undergoing neuronavigated left DLPFC rTMS. Seed-based analyses were performed with and without global signal regression pre-processing to identify biomarkers of short-term and long-term treatment response. Receiver Operating Characteristic curve and supervised machine learning analyses were applied to assess the clinical utility of these biomarkers for the classification of categorical rTMS response. RESULTS: Regardless of the pre-processing method, DLPFC-sgACC connectivity was not associated with treatment outcome. Instead, poorer connectivity between the sgACC and three clusters (peak locations: frontal pole, superior parietal lobule, occipital cortex) and DLPFC-central opercular cortex were observed in long-term nonresponders. The identified connections could serve as acceptable to excellent markers. Combining the features using supervised machine learning reached accuracy rates of 95.35% (CI=82.94-100.00) and 88.89% (CI=63.96-100.00) in the cross-validation and test dataset, respectively. LIMITATIONS: The sample size was moderate, and features for machine learning were based on group differences. CONCLUSIONS: Long-term nonresponders showed greater disrupted connectivity in regions involving the central executive network. Our findings may aid the development of personalized medicine for medication-refractory depression.

The relationship between visceral adiposity and cardiometabolic risk in Chinese women with polycystic ovary syndrome.

OBJECTIVE: To compare the extent to which visceral adiposity, as measured by mesenteric fat thickness, contribute to cardiometabolic risk, especially insulin resistance, in women with PCOS and healthy control. METHODS: This is a cross-sectional study with a total of 190 women with PCOS fulfilling the Rotterdam diagnostic criteria. Women without PCOS were recruited from a previous study, which comprised 416 healthy women controls with normal glucose tolerance. All subjects underwent OGTT, biochemical assessment, and sonographic assessment with measurements of mesenteric, preperitoneal and subcutaneous fat thickness. RESULTS: Mesenteric fat thickness was strongly correlated to cardiometabolic traits including blood pressure, fasting and 2-h glucose, triglycerides, HOMA-IR; and was negatively correlated to HDL-C in both cohorts (all p < 0.01). In PCOS, positive correlation was observed between mesenteric fat thickness and free androgen index (p < 0.01). Compared with controls, the regression line between mesenteric fat and HOMA-IR is much steeper in PCOS (p < 0.01). CONCLUSION: Women with PCOS remain more insulin resistant compared to controls at any given degree of visceral adiposity.

The age-related white matter changes scale correlates with cognitive impairment.

BACKGROUND AND PURPOSE: Age-related white matter changes (ARWMC) are closely associated with cognitive impairment. Although the ARWMC scale has been widely used to grade white matter changes (WMC) severity, the correlation between this scale and cognitive impairment has not been studied. We aimed to validate the ARWMC scale against cognition in patients with stroke. METHODS: We determined the severity of WMC for 172 patients with stroke on MRI by volumetric quantification and the ARWMC scale. Two scores (total score and global score) were derived from the ARWMC scale. We assessed executive function and global cognition using the Mattis dementia rating scale-initiation/perseveration subset (MDRS I/P) and mini-mental state examination (MMSE), respectively. We investigated the association between the three WMC measures (volume, total score, and global score) and clinical variables with cognitive impairment using multivariate regression analysis. RESULTS: Even after adjusting for other clinical variables, total score and global score of ARWMC scale were independently associated with MDRS I/P (beta = -0.248, P = 0.001 and beta = -0.218, P = 0.005, respectively) and MMSE (adjusted odds ratio 1.181, 95%CI [1.038-1.343] and adjusted odds ratio 1.740, 95%CI [1.063-2.847], respectively). CONCLUSION: The ARWMC scale correlates well with cognitive impairment in patients with stroke.

Intraventricular amphotericin for absidiomycosis in an immunocompetent child.

Brain abscesses are uncommon in children. We report a 3-year-old, previously healthy and immunocompetent boy, with an Absidia brain abscess. He presented with decreased sensorium and status epilepticus. The brain abscess was detected using cranial computed tomography and magnetic resonance imaging, and the diagnosis was confirmed with pus and brain tissue cultures. The patient responded to surgical drainage with concomitant intravenous and intraventricular amphotericin B.

Sequential spine-hand radiography for assessing skeletal maturity with low radiation EOS imaging system for bracing treatment recommendation in adolescent idiopathic scoliosis: a feasibility and validity study.

PURPOSE: The EOS-imaging system is increasingly adopted for clinical follow-up in scoliosis with the advantages of simultaneous biplanar imaging of the spine in an erect position. Skeletal maturity assessment using a hand radiograph is an essential adjunct to spinal radiography in scoliosis follow-up. This study aims at testing the feasibility and validity of a newly proposed EOS workflow with sequential spine-hand radiography for skeletal maturity assessment and bracing recommendation. METHODS: EOS spine-hand radiographs from patients with diagnosis of idiopathic scoliosis, including both sexes and an age range of ten to 14 years, were scored using the Thumb Ossification Composite Index (TOCI), Sanders and Risser methods. Intraclass correlation coefficients (ICCs) were calculated for inter/intraobserver agreement and were tested with Cronbach's alpha values. RESULTS: In all, 60 EOS-spine hand radiographs selected from subjects with diagnosis of adolescent idiopathic scoliosis (AIS), including 32 male patients (mean age 11.53 years; 10 to 14) and 28 female patients (mean age 11.50 years; 10 to 13) who underwent sequential spine-hand low dose EOS imaging were generated for analysis. The overall interobserver (ICC = 0.997) and intraobserver agreement (α > 0.9) demonstrated excellent agreement for TOCI staging; ICC > 0.994 for both TOCI and Sanders staging comparing traditional digital versus EOS hand radiography; ICC ≥ 0.841 for agreement on bracing recommendation among TOCI versus the Risser and Sanders system. CONCLUSION: With the proposed new EOS workflow it was feasible to produce high image quality for skeletal maturity assessment with excellent reliability and validity to inform consistent bracing recommendation in AIS. The workflow is applicable for busy daily clinic settings in tertiary scoliosis centres with reduced time cost, improved efficiency and throughput of the radiology department. LEVEL OF EVIDENCE: III.

Altered White Matter Microstructure in the Corpus Callosum and Its Cerebral Interhemispheric Tracts in Adolescent Idiopathic Scoliosis: Diffusion Tensor Imaging Analysis.

BACKGROUND AND PURPOSE: Neural system was one of the important contributors to the etiopathogenesis of adolescent idiopathic scoliosis; additionally, the morphology of corpus callosum interconnecting both hemispheres of the brain was found to be altered morphologically. Our aim was to evaluate and compare the microstructural changes of the corpus callosum and its interhemispheric white matter fiber tracts interconnecting both cerebral hemispheres in patients with adolescent idiopathic scoliosis and matched controls using diffusion tensor imaging. MATERIALS AND METHODS: Brain DTI was performed in 69 patients with adolescent idiopathic scoliosis (female, right thoracic/thoracolumbar curve) and 40 age-matched controls without adolescent idiopathic scoliosis (female). 2D and 3D segmentation of the corpus callosum were performed using a region-growing method, and the corpus callosum was further divided into 6 regions, including the rostrum, genu, anterior and posterior midbodies, isthmus, and splenium. The laterality index was calculated to quantify the asymmetry of the corpus callosum. Interhemispheric fiber tractography were performed using the Brodmann atlas. RESULTS: 2D ROI analysis revealed reduced fractional anisotropy in the genu and splenium (P = .075 and P = .024, respectively). Consistently reduced fractional anisotropy on the left sides of the genu and splenium was also found in 3D ROI analysis (P = .03 and P = .012, respectively). The laterality index analysis revealed a pseudo-right lateralization of the corpus callosum in adolescent idiopathic scoliosis. Interhemispheric fibers via the splenium interconnecting Brodmann 3, 1, and 2; Brodmann 17; and Brodmann 18 (corresponding to the primary somatosensory cortex and primary and secondary visual cortices) were also found to have reduced fractional anisotropy (P ≤ .05). CONCLUSIONS: Reduced fractional anisotropy was found in the genu and splenium of the corpus callosum and corresponding interhemispheric fiber tracts interconnecting the somatosensory and visual cortices via the splenium. Our results are suggestive of altered white matter microstructure within the brain of those with adolescent idiopathic scoliosis, which could be related to abnormal brain maturation during adolescence in adolescent idiopathic scoliosis and could possibly explain the previously documented somatosensory function impairment and visuo-oculomotor dysfunction in this condition.

Molecular and clinical characterization of citrin deficiency in a cohort of Chinese patients in Hong Kong.

BACKGROUND AND OBJECTIVES: This retrospective study analysed a case series of subjects with citrin deficiency, and aims to present the molecular and clinical characterization of this disease in the Hong Kong Chinese population for the first time. PATIENTS AND METHODS: Data from medical records of eighteen patients with citrin deficiency (years 2006-2015) were retrieved. Demographic data, biochemical parameters, radiological results, genetic testing results, management, and clinical outcome were collected and analysed. RESULTS: Eighteen patients with diagnosis of citrin deficiency were recruited. All 18 patients carried at least one common pathogenic variant c.852_855delTATG in SLC25A13. Prolonged jaundice (neonatal intrahepatic cholestasis caused by citrin deficiency, NICCD) was the most common presenting symptom, in conjunction with elevated plasma citrulline, threonine, alkaline phosphatase, and alpha-fetoprotein levels. The abnormal biochemical parameters including liver derangement returned to normal range in most of the cases by 6 months of age after the introduction of a lactose-free formula. There were a few cases with atypical presentations. Two subjects did not present with NICCD, and were subsequently diagnosed later in life after their siblings presented with symptoms of citrin deficiency at one month of age and subsequently received a molecular diagnosis. One patient with citrin deficiency also exhibited multiple liver hemangioendotheliomas, which subsided gradually after introduction of a lactose-free formula. Only one patient from this cohort was offered expanded metabolic screening at birth. She was not ascertained by conducted newborn screening and was diagnosed upon presentation with cholestatic jaundice by 1 month of age. CONCLUSION: This is the first report of the clinical and molecular characterization of a large cohort of patients with citrin deficiency in Hong Kong. The presentation of this cohort of patients expands the clinical phenotypic spectrum of NICCD. Benign liver tumors such as hemangioendotheliomas may be associated with citrin deficiency in addition to the well-known association with hepatocellular carcinoma. Citrin deficiency may manifest in later infancy period with an NICCD-like phenotype. Furthermore, this condition is not always ascertained by expanded newborn metabolic screening testing.

Role of radiologic features in the management of papillary lesions of the breast.

OBJECTIVE: The purpose of our study was to assess the role of imaging and core biopsy in the management of patients with papillary lesions of the breast. MATERIALS AND METHODS: Clinical records and mammographic and sonographic findings of 40 women with papillary lesions in the breast were retrieved. The imaging features and cytologic findings were correlated with histologic findings. RESULTS: Fifty-six papillary lesions in 40 patients underwent either mastectomy, segmental duct resection, or excision biopsy. There were three papillary carcinomas, 13 papillaryal lesions with carcinoma in situ, one atypical papilloma, four sclerosed papillomata, and 35 papillomata. Of these lesions, 37.5% (21/56) and 82.1% (46/56) could be detected on mammography and sonography, respectively. Galactography and dilated ducts helped to suggest the papillary nature of the lesions. However, mammography and sonography were not able to predict malignancy (sensitivity, 69% and 56%, respectively; specificity, 25% and 90%; positive predictive value [PPV], 60% and 75%; and negative predictive value [NPV], 33% and 90%). Combined interpretation of mammography and sonography gave a sensitivity of 61%, specificity of 33%, PPV of 85%, and NPV of 13%. Fine-needle aspiration gave a sensitivity of 44%, specificity of 68%, PPV of 31%, and NPV of 79%, whereas core biopsy gave a sensitivity of 82%, specificity of 100%, PPV of 100%, and NPV of 83% in the diagnosis of malignancy. CONCLUSION: Radiologic features are not sufficiently sensitive or specific to differentiate benign from malignant papillary lesions. Fine-needle aspiration and core biopsy have pitfalls, and the need for surgical excision of all papillary lesions should be revisited.

Intravenous leiomyomatosis: computed tomography diagnosis.

Intravenous leiomyomatosis is a rare neoplastic condition characterised by nodular masses of histologically benign smooth muscle growing within veins. In most cases, the disease is confined to the pelvic veins, but involvement may extend to the inferior vena cava and right heart chamber. We report the computed tomography features of a woman who developed extensive intravenous leiomyomatosis and lung metastases, and presented with acute-onset lower limb swelling.

Curve correction effect of rigid spinal orthosis in different recumbent positions in adolescent idiopathic scoliosis (AIS): a pilot MRI study.

In this pilot cross-sectional study, the effectiveness of rigid spinal orthoses in the correction of spinal curvature of 14 patients with moderate adolescent idiopathic scoliosis (AIS) at different recumbent positions (supine, prone, right and left decubitus) was investigated. Using magnetic resonance (MR) imaging and multi-planar reconstruction technique, evaluation of the scoliotic spine in the coronal, sagittal and axial planes and the effect of spinal orthosis on AIS at different recumbent positions was studied. There was significant reduction of coronal Cobb's angle (p < 0.05) with bracing at all four recumbent positions and the maximal reduction was found in the prone position (18% reduction). The sagittal Cobb's angle was only significantly reduced at the supine position while the axial rotation did not change significantly in all positions.

Liver fibrosis and fatty liver in Asian HIV-infected patients.

BACKGROUND: Little is known about the importance of liver fibrosis and fatty liver in HIV-monoinfected individuals without hepatitis virus co-infection, particularly among the Asian population. AIM: To evaluate prevalence and risk factors for liver fibrosis and fatty liver in Asian HIV-monoinfected individuals. METHODS: Eighty asymptomatic HIV-monoinfected individuals (tested negative for HBV/HCV) were compared with 160 matched HIV-uninfected healthy controls. Transient elastography and proton-magnetic resonance spectroscopy ((1) H-MRS) were performed to measure liver stiffness and hepatic steatosis respectively. Blood samples were analysed for metabolic profiles and markers of steatohepatitis (e.g. cytokeratin-18). RESULTS: All HIV-infected individuals (mean ± s.d. age 54 ± 11 years, male 93%, Chinese 94%; diagnosis median duration 8 (IQR 4-13 years) were stable on anti-retrovirals (PI-based 58.7%, NNRTI-based 25.0% integrase-inhibitors 16.3%); diabetes, dyslipidaemia, and metabolic syndrome were common. Fatty liver disease was detected in 28.7%. There was significantly higher degree of liver stiffness [4.9 (IQR 4.1-6.2) kPa vs. 4.2 (IQR 3.6-5.0) kPa, P < 0.001], and greater proportions developed significant fibrosis (7.0 kPa, 14.3% vs. 3.1%, P = 0.001) and cirrhosis (10.3 kPa, 5.2% vs. 0.6%, P = 0.040) compared with controls. HIV infection was an independent risk factor for significant fibrosis (adjusted OR 4.00, 95% CI 1.29-12.41, P = 0.016). HIV-infected individuals with fatty liver had excessive liver stiffness and fibrosis. Two cases of asymptomatic hepatocellular carcinoma were detected. CONCLUSIONS: HIV-monoinfected patients are at risk for liver fibrosis and cirrhosis. HIV-related mechanisms and fatty liver disease may play important roles. Screening and intervention to prevent severe outcomes should be considered.