Hypoattenuating periportal halo on CT in a patient population can occur in presence of a variety of diseases

Many pathologies can occur in the periportal space and manifest as fluid accumulation, visible in Computed tomography (CT) images as a circumferential region of low attenuation around the intrahepatic portal vessels, called periportal halo (PPH). This finding is associated with different types of hepatic and extra-hepatic disease in humans and remains a non-specific sign of unknown significance in veterinary literature. The aim of this study was to investigate the prevalence of PPH in a population of patients undergoing CT examination and to assess the presence of lesions related to hepatic and extra-hepatic disease in presence of PPH. CT studies including the cranial abdomen of dogs and cats performed over a 5-year period were retrospectively reviewed. The prevalence of PPH was 15% in dogs and 1% in cats. 143 animals were included and the halo was classified as mild, moderate and severe, respectively in 51%, 34% and 15% of animals. The halo distribution was generalized in 79 cases, localized along the second generation of portal branches in 63, and along the first generation only in one. Hepatic disease was present in 58/143 and extra-hepatic disease in 110/143 of the cases. Main cause of hepatic (36%) and extra-hepatic disease (68%) was neoplasia. Associations between halo grades and neoplasia revealed to be not statistically significant (p = 0.057). In 7% of animals the CT examination was otherwise unremarkable. PPH is a non-specific finding, occurring in presence of a variety of diseases in the examined patient population.

Skip hemilaminectomy for the treatment of holospinal epidural abscess: A single-center experience

Background: Holospinal epidural abscesses (HEAs) are rare with potentially devastating consequences. Urgent bony decompression and abscess evacuation with long-term antibiotic therapy are typically the treatment of choice. Methods: We reviewed cases of holospinal HEAs operated on between 2009 and 2018. Variables studied included preoperative laboratories, CT/MR studies plus clinical and radiographic follow-up for between 34 and 60 postoperative months. Results: We utilized skip hemilaminectomies to minimize the risks of segmental instability. Targeted antibiotic therapy was also started immediately and maintained for 6 postoperative weeks. MR/CT studies documented full radiographic and neurological recovery between 6 and 12-months later. Conclusion: HEAs may be treated utilizing multilevel skip hemilaminectomies to help maintain spinal stability while offering adequate abscess decompression/resolution.

Commercial AI solutions in detecting COVID-19 pneumonia in chest CT: not yet ready for clinical implementation?

Objectives In response to the COVID-19 pandemic, many researchers have developed artificial intelligence (AI) tools to differentiate COVID-19 pneumonia from other conditions in chest CT. However, in many cases, performance has not been clinically validated. The aim of this study was to evaluate the performance of commercial AI solutions in differentiating COVID-19 pneumonia from other lung conditions. Methods Four commercial AI solutions were evaluated on a dual-center clinical dataset consisting of 500 CT studies; COVID-19 pneumonia was microbiologically proven in 50 of these. Sensitivity, specificity, positive and negative predictive values, and AUC were calculated. In a subgroup analysis, the performance of the AI solutions in differentiating COVID-19 pneumonia from other conditions was evaluated in CT studies with ground-glass opacities (GGOs). Results Sensitivity and specificity ranges were 62–96% and 31–80%, respectively. Negative and positive predictive values ranged between 82–99% and 19–25%, respectively. AUC was in the range 0.54–0.79. In CT studies with GGO, sensitivity remained unchanged. However, specificity was lower, and ranged between 15 and 53%. AUC for studies with GGO was in the range 0.54–0.69. Conclusions This study highlights the variable specificity and low positive predictive value of AI solutions in diagnosing COVID-19 pneumonia in chest CT. However, one solution yielded acceptable values for sensitivity. Thus, with further improvement, commercial AI solutions currently under development have the potential to be integrated as alert tools in clinical routine workflow. Randomized trials are needed to assess the true benefits and also potential harms of the use of AI in image analysis. Key Points • Commercial AI solutions achieved a sensitivity and specificity ranging from 62 to 96% and from 31 to 80%, respectively, in identifying patients suspicious for COVID-19 in a clinical dataset. • Sensitivity remained within the same range, while specificity was even lower in subgroup analysis of CT studies with ground-glass opacities, and interrater agreement between the commercial AI solutions was minimal to nonexistent. • Thus, commercial AI solutions have the potential to be integrated as alert tools for the detection of patients with lung changes suspicious for COVID-19 pneumonia in a clinical routine workflow, if further improvement is made.

Evaluation of High-Volume Injections Using a Modified Dorsal Quadratus Lumborum Block Approach in Canine Cadavers

The quadratus lumborum (QL) block targets the fascial plane surrounding the QL muscle providing abdominal somatic and visceral analgesia. The extension of its analgesic effects is a subject of research, as it could not cover areas of the cranial abdomen in dogs. This study assesses in eight thawed canine cadavers, the distribution of high-volume injections (0.6 mL kg−1 of a mixture of methylene blue and iopromide) injected between the psoas minor muscle and the vertebral body of L1. Anatomical features of the area of interest were studied in two cadavers. In another six dogs, QL blocks were performed bilaterally under ultrasound-guidance. The distribution of contrast was evaluated by computed tomography (CT). Hypaxial abdominal muscles were dissected to visualize the dye spread (spinal nerves and sympathetic trunk) in 5 cadavers. The remaining cadaver was refrozen and cross-sectioned. CT studies showed a maximum distribution of contrast from T10 to L7. The methylene blue stained T13 (10%), L1 (100%), L2 (100%), L3 (100%), L4 (60%) and the sympathetic trunk T10 (10%), T11 (20%), T12 (30%), T13 (70%), L1 (80%), L2 (80%), L3 (60%) and L4 (30%). These findings may suggest that despite the high volume of injectate administered, this modified QL block could not produce somatic analgesia of the cranial abdomen, although it could provide visceral analgesia in dogs.

Automated artificial intelligence-based analysis of skeletal muscle volume predicts overall survival after cystectomy for urinary bladder cancer

Background Radical cystectomy for urinary bladder cancer is a procedure associated with a high risk of complications, and poor overall survival (OS) due to both patient and tumour factors. Sarcopenia is one such patient factor. We have developed a fully automated artificial intelligence (AI)-based image analysis tool for segmenting skeletal muscle of the torso and calculating the muscle volume. Methods All patients who have undergone radical cystectomy for urinary bladder cancer 2011–2019 at Sahlgrenska University Hospital, and who had a pre-operative computed tomography of the abdomen within 90 days of surgery were included in the study. All patients CT studies were analysed with the automated AI-based image analysis tool. Clinical data for the patients were retrieved from the Swedish National Register for Urinary Bladder Cancer. Muscle volumes dichotomised by the median for each sex were analysed with Cox regression for OS and logistic regression for 90-day high-grade complications. The study was approved by the Swedish Ethical Review Authority (2020-03985). Results Out of 445 patients who underwent surgery, 299 (67%) had CT studies available for analysis. The automated AI-based tool failed to segment the muscle volume in seven (2%) patients. Cox regression analysis showed an independent significant association with OS (HR 1.62; 95% CI 1.07–2.44; p = 0.022). Logistic regression did not show any association with high-grade complications. Conclusion The fully automated AI-based CT image analysis provides a low-cost and meaningful clinical measure that is an independent biomarker for OS following radical cystectomy.

A Comprehensive Update of the Incidence and Demographics of Laryngoceles in Adults

Objective: To provide updated data on the incidence, types, and demographics of laryngoceles in the adult population. Methods: We searched the medical archives of our institute for computed tomography (CT) studies acquired between January 1, 2007 and December 31, 2017 in which the term “laryngocele” appeared in the radiology reports. Two of the authors reviewed relevant images for the presence, type, distribution, and laterality of true laryngoceles. Demographic and clinical data were extracted from medical records and the incidence was calculated. Results: Laryngoceles were detected in 53 out of the 79 893 patients with relevant CT data, which equates to an incidence of 151 per 2.5 million (0.06:1000) patients per year. The male:female ratio was 3:1, average age was 60 (±18) years, and incidence peaked among patients in the sixth decade of life. Nine patients (17%) had known laryngeal cancer; however, the majority of the cohort did not have follow up clinic visits. Conclusion: Our study demonstrates that the incidence of laryngoceles is much greater than previously reported. In most cases, the diagnosis of a laryngocele was an incidental radiological finding. Male gender predilection and age at presentation are in agreement with previous reports. Association of laryngoceles with laryngeal cancer could not be calculated due to low rates of follow ups. Level of Evidence: 3.

Evolution of CT patterns in novel coronavirus (2019-nCoV) pneumonia in relation to clinical and laboratory data

Introduction. The CT patterns of coronavirus pneumonia are clear and represent certain pathomorphosis at the period of coronavirus pandemic. However, there are a lot of questions about influence of CT-patterns and their dynamic change on a disease’s severity. The aim of the study. To evaluate the dynamics of pulmonary CT changes of novel coronavirus (2019-nCoV) pneumonia in relation to clinical and laboratory data. Materials and methods. CT studies in dynamics of 108 patients with a of novel coronavirus (2019-nCoV) pneumonia were analyzed. The first CT study was performed on admission (6,7±4,1 days of the disease), the first control CT on 11,1±4,9 days of the disease, and the second CT control was performed on 16,7±5,6 days of the disease. Results. The volume of the lesion and the predominant CT symptom at admission did not affect the prognosis. However, changes in the repeated CT study had a high prognostic value. Thus, the occurrence of a pattern of organizing pneumonia during repeated study is associated with a good prognosis, while an increase in the zones of «crazy paving» and a larger volume of damage are unfavorable prognostic signs. An increase in the volume of changes in the type of ground glass and «crazy paving» correlated with increased levels of C-reactive protein, lactate dehydrogenase, and lymphopenia. Conclusion. Data from CT studies in dynamics for novel coronavirus (2019-nCoV) pneumonia have a prognostic value and, in combination with clinical and laboratory data, can influence decision-making on patient management.