Application of deep learning algorithms in classification and localization of implant cutout for the postoperative hip.

OBJECTIVE: This study aims to explore the feasibility of employing convolutional neural networks for detecting and localizing implant cutouts on anteroposterior pelvic radiographs. MATERIALS AND METHODS: The research involves the development of two Deep Learning models. Initially, a model was created for image-level classification of implant cutouts using 40191 pelvic radiographs obtained from a single institution. The radiographs were partitioned into training, validation, and hold-out test datasets in a 6/2/2 ratio. Performance metrics including the area under the receiver operator characteristics curve (AUROC), sensitivity, and specificity were calculated using the test dataset. Additionally, a second object detection model was trained to localize implant cutouts within the same dataset. Bounding box visualizations were generated on images predicted as cutout-positive by the classification model in the test dataset, serving as an adjunct for assessing algorithm validity. RESULTS: The classification model had an accuracy of 99.7%, sensitivity of 84.6%, specificity of 99.8%, AUROC of 0.998 (95% CI: 0.996, 0.999) and AUPRC of 0.774 (95% CI: 0.646, 0.880). From the pelvic radiographs predicted as cutout-positive, the object detection model could achieve 95.5% localization accuracy on true positive images, but falsely generated 14 results from the 15 false-positive predictions. CONCLUSION: The classification model showed fair accuracy for detection of implant cutouts, while the object detection model effectively localized cutout. This serves as proof of concept of using a deep learning-based approach for classification and localization of implant cutouts from pelvic radiographs.

Plasma Metanephrines Yield Fewer False-Positive Results Than Urine Metanephrines in Patients With Obstructive Sleep Apnea.

CONTEXT: Obstructive sleep apnea (OSA) is associated with increased nocturnal sympathetic activity. In OSA patients, elevations in metanephrines may lead to false-positive tests when evaluating for pheochromocytoma or paraganglioma (PPGL). OBJECTIVE: To evaluate whether morning plasma metanephrines would lead to fewer false-positive results than 24-hour urinary metanephrines in OSA patients. METHODS: Patients undergoing polysomnography for suspected OSA were recruited. Plasma free and 24-hour urinary metanephrines were measured by HPLC-MS/MS. Patients with elevated levels had repeat measurements, abdominal imaging, and follow-up to diagnose or exclude a PPGL. RESULTS: Seventy-six patients completed polysomnography and biochemical testing; 68 (89.5%) patients had OSA, of whom 19 (27.9%) had elevated plasma and/or urinary metanephrines. On follow-up, one patient had a bladder paraganglioma, while PPGL was excluded in the remaining patients. OSA patients had more false-positive urinary metanephrines (17 of 67, 25.4%) than plasma metanephrines (2 of 67, 3.0%), P < .01, and this was more common in severe OSA (13 of 34, 38.2%), compared to moderate/mild OSA (4 of 33, 12.1%), P < .01. Both plasma and urinary metanephrines decreased after treatment with continuous positive airway pressure. On multivariable analysis, severe OSA, obesity, and family history of hypertension were positive predictors for false-positive urinary metanephrines in patients with suspected OSA. CONCLUSION: In OSA patients, plasma metanephrines are less likely to yield false-positive results for the diagnosis of PPGL than 24-hour urinary metanephrines. In patients with suspected OSA, obesity, or a family history of hypertension, plasma metanephrines may be the preferred first-line test to avoid unnecessary anxiety or follow-up.

Application of a deep learning algorithm in the detection of hip fractures.

This paper describes the development of a deep learning model for prediction of hip fractures on pelvic radiographs (X-rays). Developed using over 40,000 pelvic radiographs from a single institution, the model demonstrated high sensitivity and specificity when applied to a test set of emergency department radiographs. This study approximates the real-world application of a deep learning fracture detection model by including radiographs with sub-optimal image quality, other non-hip fractures, and metallic implants, which were excluded from prior published work. The study also explores the effect of ethnicity on model performance, as well as the accuracy of visualization algorithm for fracture localization.

11C-Metomidate PET-CT versus adrenal vein sampling to subtype primary aldosteronism: a prospective clinical trial.

OBJECTIVE: Adrenal vein sampling (AVS) is recommended to subtype primary aldosteronism, but it is technically challenging. We compared 11C-Metomidate-PET-computed tomography (PET-CT) and AVS for subtyping of primary aldosteronism. METHODS: Patients with confirmed primary aldosteronism underwent both AVS and 11C-Metomidate PET-CT (post-dexamethasone). All results were reviewed at a multidisciplinary meeting to decide on final subtype diagnosis. Primary outcome was accuracy of PET versus AVS to diagnosis of unilateral primary aldosteronism based on post-surgical biochemical cure. Secondary outcome was accuracy of both tests to final subtype diagnosis. RESULTS: All 25 patients recruited underwent PET and successful AVS (100%). Final diagnosis was unilateral in 22 patients, bilateral in two and indeterminate in one due to discordant lateralization. Twenty patients with unilateral primary aldosteronism underwent surgery, with 100% complete biochemical success, and 75% complete/partial clinical success. For the primary outcome, sensitivity of PET was 80% [95% confidence interval (95% CI): 56.3-94.3] and AVS was 75% (95% CI: 50.9-91.3). For the secondary outcome, sensitivity and specificity of PET was 81.9% (95% CI: 59.7-94.8) and 100% (95% CI: 15.8-100), and AVS was 68.2% (95% CI: 45.1-86.1) and 100% (95% CI: 15.8-100), respectively. Twelve out of 20 (60%) patients had both PET and AVS lateralization, four (20%) PET-only, three (15%) AVS-only, while one patient did not lateralize on PET or AVS. Post-surgery outcomes did not differ between patients identified by either test. CONCLUSION: In our pilot study, 11C-Metomidate PET-CT performed comparably to AVS, and this should be validated in larger studies. PET identified patients with unilateral primary aldosteronism missed on AVS, and these tests could be used together to identify more patients with unilateral primary aldosteronism. VIDEO ABSTRACT: http://links.lww.com/HJH/B918.

Treatment of Primary Aldosteronism and Reversal of Renin Suppression Improves Left Ventricular Systolic Function.

Introduction: Primary aldosteronism (PA) is associated with increased risk of cardiovascular events. However, treatment of PA has not been shown to improve left ventricular (LV) systolic function using the conventional assessment with LV ejection fraction (LVEF). We aim to use speckle-tracking echocardiography to assess for improvement in subclinical systolic function after treatment of PA. Methods: We prospectively recruited 57 patients with PA, who underwent 24-h ambulatory blood pressure (BP) measurements and echocardiography, including global longitudinal strain (GLS) assessment of left ventricle, at baseline and 12 months post-treatment. Results: At baseline, GLS was low in 14 of 50 (28.0%) patients. On multivariable analysis, GLS was associated with diastolic BP (P = 0.038) and glomerular filtration rate (P = 0.026). GLS improved post-surgery by -2.3, 95% CI: -3.9 to -0.6, P = 0.010, and post-medications by -1.3, 95% CI: -2.6 to 0.03, P = 0.089, whereas there were no changes in LVEF in either group. Improvement in GLS was independently correlated with baseline GLS (P < 0.001) and increase in plasma renin activity (P = 0.007). Patients with post-treatment plasma renin activity ≥1 ng/ml/h had improvements in GLS (P = 0.0019), whereas patients with persistently suppressed renin had no improvement. Post-adrenalectomy, there were also improvements in LV mass index (P = 0.012), left atrial volume index (P = 0.002), and mitral E/e' (P = 0.006), whereas it was not statistically significant in patients treated with medications. Conclusion: Treatment of hyperaldosteronism is effective in improving subclinical LV systolic dysfunction. Elevation of renin levels after treatment, which reflects adequate reversal of sodium overload state, is associated with better systolic function after treatment. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT03174847.

Renal Cell Carcinoma Mimicking Transitional Cell Carcinoma: A Case Report.

BACKGROUND Preoperative differentiation between renal cell carcinoma (RCC) and transitional cell carcinoma (TCC) is of utmost important for determining surgical strategy, whether nephrectomy or nephro-ureterectomy, as well as the necessity for wider lymphadenectomy and subsequent intensive surveillance, as the latter is more prone to recurrence. CASE REPORT A 76-year-old Chinese woman presented with flank pain and gross hematuria, and was found to have right-sided hydronephrosis. An obstructing tumor in the renal pelvis was shown on a computed tomography (CT) intravenous pyelogram. Although its enhancement pattern was suggestive of RCC, the location within the collecting system without any attachment to the renal parenchyma is very unusual. The mass was diagnosed histopathologically as RCC on both ureteroscopic biopsy and subsequent radical nephrectomy. CONCLUSIONS We present a rare case of RCC growing exclusively in the renal pelvis, mimicking a TCC. Hypotheses regarding this unusual presentation include direct invasion, continuous implantation, and intraluminal transit down the collecting system. The characteristics on imaging studies, including greater enhancement and higher tumor-to-kidney attenuation ratio, may provide a clue for diagnosis, but ureteroscopy and histopathology are the criterion standards and should be considered as part of routine preoperative assessment. Amidst controversies and inconsistencies, more and more emerging evidence suggests that RCC with urinary collecting system invasion is associated with less favorable overall and recurrence-free survival, especially in localized diseases.

Improvement in quality of life and psychological symptoms after treatment for primary aldosteronism: Asian Cohort Study.

BACKGROUND: In addition to increased cardiovascular risk, patients with primary aldosteronism (PA) also suffer from impaired health-related quality of life (HRQoL) and psychological symptoms. We assessed for changes in HRQoL and depressive symptoms in a cohort of Asian patients with PA, after surgical and medical therapy. METHODS: Thirty-four patients with PA were prospectively recruited and completed questionnaires from 2017 to 2020. HRQoL was assessed using RAND-36 and EQ-5D-3L, and depressive symptoms were assessed using Beck Depression Inventory (BDI-II) at baseline, 6 months, and 1 year post-treatment. RESULTS: At 1 year post-treatment, significant improvement was observed in both physical and mental summative scores of RAND-36, +3.65, P = 0.023, and +3.41, P = 0.033, respectively, as well as four subscale domains (physical functioning, bodily pain, role emotional, and mental health). Significant improvement was also seen in EQ-5D dimension of anxiety/depression at 1 year post-treatment. Patients treated with surgery (n = 21) had significant improvement in EQ-5D index score post-treatment and better EQ-5D outcomes compared to the medical group (n = 13) at 1 year post-treatment. 37.9, 41.6 and 58.6% of patients had symptoms in the cognitive, affective and somatic domains of BDI-II, respectively. There was a significant improvement in the affective domain of BDI-II at 1 year post-treatment. CONCLUSION: Both surgical and medical therapy improve HRQoL and psychological symptoms in patients with PA, with surgery providing better outcomes. This highlights the importance of early diagnosis, accurate subtyping and appropriate treatment of PA.

Analysis of comparative performance of CEUS and CECT/MR LI-RADS classification: Can CEUS dichotomize LI-RADS indeterminate lesions on CT or MRI?

PURPOSE: To study the comparative performance of contrast-enhanced ultrasound (CEUS) and contrast-enhanced CT or MRI (CECT/MR) in evaluating liver lesions using the LI-RADS guidelines. METHODS: Retrospective analysis of radiology database from July 2010 to April 2017 revealed 228 patients who had CECT/MR and CEUS. Patients at risk of hepatocellular carcinoma (HCC), had contemporaneous CEUS and CECT/CEMR studies within 3 months and adequate follow up were included; reviewed (2 reviewers) and graded according to the 2017 CEUS and 2018 CECT/MR LI-RADS guidelines. Reference standard was multidisciplinary clinical decisions, histology or follow-up imaging. RESULTS: The study cohort consisted of 45 patients with 46 lesions. HCC were significantly larger than non-malignant (mean sizes of 2.5 and 1.4 cm, respectively, p<0.001). Intraclass correlation coefficient for CEUS review (0.941) was higher than of CECT/MR review (0.643). Mean area-under-ROC curve (AUC) for CEUS (0.994) was significantly higher than of CECT/MR (0.760) for all lesions (p=0.01). For lesions scored LR-3 by CECT/MR, the AUC was significantly higher for CEUS (0.978) than CECT/MR (0.500) (p<0.001). Twenty-one (of 27) lesions, classified LR-3 or LR-4 by CECT/MR were upgraded by CEUS and 20 were found to be HCC. Six lesions that were LR-3 on both CECT/MR and CEUS were found to be non-malignant. There was good concordance for LR-5 lesions between both techniques. CONCLUSION: CEUS is useful for reassessment of lesions with intermediate probability (LR-3) or probable for HCC (LR-4) on CECT/MR. Lesions upgraded by CEUS tend to be HCC. Lesions that remain LR-3 on CEUS tend to be non-malignant.

Spectrum of computed tomography manifestations of appendiceal neoplasms: acute appendicitis and beyond.

Appendiceal neoplasms are rare and often only discovered incidentally during surgery performed for acute appendicitis. Computed tomography (CT) has been demonstrated to be a reliable technique for accurately establishing the preoperative diagnosis of appendiceal neoplasms that manifest as acute appendicitis through the presence of certain imaging findings. Other manifestations of appendiceal neoplasms include appendiceal mass, mucocoele, localised abscess formation, ileus, increasing abdominal girth from pseudomyxoma peritonei, and intussusception. This pictorial essay illustrates varied CT findings of neoplasms of the appendix, with emphasis on the more commonly encountered manifestations of these tumours.

Psychosocial Motivators for Moderate Drinking among Young Asian Flushers in Singapore.

Asians are more susceptible to alcohol flush syndrome and its associated health risks because they are genetically predisposed towards it. Guided by the theory of planned behaviour, this research examined the psychosocial factors associated with moderate alcohol consumption, in order to inform the development of a health campaign targeting young Asian "flushers" in Singapore. We employed a mixed-method design comprising an online survey and focus group discussions. The survey results identified perceived behavioural control as the most salient belief associated with moderate drinking intentions, particularly for Asian flushers. Although Asian flushers had more positive attitudes towards, and perceived behavioural control about drinking in moderation, they were more likely to consider that their peers disapprove of such a practice, compared to non-flushers. Additionally, Asian flushers did not consider themselves as having a higher risk of long-term health effects from alcohol consumption than non-Flushers despite their actual high-risk status. Focus group findings suggest that young Asian flushers have poor knowledge of, and skills associated with moderate drinking, in addition to feeling self-imposed social pressure. The study findings provide practical insights into bridging the information gap on Asian flush and promoting Asian flushers' drinking in moderation.

Torsion of a Myomatous, Non-gravid Uterus: CT Findings.

Uterine torsion is a rare condition which is part of a spectrum of gynecological emergencies. If diagnosis is delayed or the condition is left untreated, severe consequences such as infertility and life-threatening complications can arise. As presenting features are often non-specific and can be similar to commonly encountered gastrointestinal and urinary conditions, computed tomography is usually the first imaging modality utilized in an emergency setting. It is therefore important that the radiologist is familiar with recognizing computed tomography features of uterine torsion. We share our findings in a patient with uterine torsion in a non-gravid uterus, diagnosed on contrast-enhanced computed tomography with multiplanar reconstruction.

Image-guided Percutaneous Transhepatic Removal of Fish Bone from Liver Abscess.

We present a case of a woman who was diagnosed with a hepatic abscess secondary to a migrated fish bone. As the patient did not improve after percutaneous drainage of the abscess, image-guided percutaneous transhepatic removal of the fish bone was performed. Fish bones in hepatic abscesses are typically removed surgically, with the fish bone left in situ in a number of cases. There has been only another reported case of percutaneous transhepatic fish bone removal. We conclude that in the rare case of a hepatic abscess complicating fish bone migration, image-guided percutaneous transhepatic removal of the offending foreign body is a feasible alternative to surgery, especially in high surgical risk patients.

Solitary necrotic nodule of the liver: radiologic-pathologic correlation in a case with unusual imaging features.

Solitary necrotic nodule of the liver (SNNL) is rare. Generally thought to be nonmalignant, it is often mistaken for malignancy based on imaging findings alone. We present a case of a hepatitis B carrier who was found to have a new sonographically detected hepatic lesion. The lesion was further evaluated with CT and MRI, and as appearances were suggestive of a hypovascular hepatoma, the lesion was surgically resected. This case is unique in that while it demonstrates several characteristic features of SNNL, several other imaging and histological features have not been previously described.

Cervical hematomyelia after traditional Chinese massage: a case report.

Hematomyelia is rare, and usually related to major trauma. Non-traumatic causes are much rarer and include underlying vascular malformations and cord tumors. We present the case of a previously well 44-year-old woman who developed severe acute neck pain and right-sided motor deficit after a session of traditional Chinese massage that entailed minimal neck manipulation. Emergent MRI confirmed hematomyelia of the right cervical hemicord, notably without associated bony or ligamentous injury. Follow-up spinal angiography and MRIs revealed no underlying vascular malformation or tumor. We highlight this case as there has been no reported case of hematomyelia occurring after mild trauma, although two cases of idiopathic hematomyelia have been reported. Though exceedingly rare, hematomyelia should be considered in the list of differential diagnoses in any case of neck pain and motor deficit after seemingly trivial injury.

Cone beam computed tomography for vascular interventional radiology procedures: early experience.

INTRODUCTION: Cone beam computed tomography (CBCT) is a relatively new technological innovation that utilises fl at-panel detector technology to obtain CT-like images. The key strength of a CBCT system is that cross-sectional imaging can be obtained using the angiographic fl at panel unit without having to move the patient, allowing the radiologist to obtain soft tissue imaging during the procedure. This allows treatment planning, guidance, and assessment of outcome to be performed in one interventional suite. MATERIALS AND METHODS: From December 2008 to June 2009, 24 CBCT scans were performed during vascular interventional procedures on our department's newly installed multi-axis fl at panel angiographic unit. RESULTS: Ten cases were performed for hepatic trans-arterial chemoembolisation, 9 cases for hepatic arterial Yttrium-90 infusion, while 5 cases were for other indications. CBCT was found to be useful in 20 of the 24 cases. CONCLUSION: Our early experience showed that CBCT was useful in impacting decisions during selected vascular interventional procedures. As CBCT technology improves, we can foresee wider applications of this technology.