Introduction: Viz.AI LVO is an artificial-intelligence platform which analyzes brain computed tomography angiography (CTA) images in patients with suspected acute ischemic stroke (AIS) and sends an automated alert for suspected large vessel occlusions (LVO). The FDA cleared Viz.AI for LVO detection and Viz.AI reports high sensitivity and specificity (96.3% and 93.8%). We report our experience with Viz.AI LVO detection at our academic comprehensive stroke center (CSC). Methods: We performed a retrospective review of suspected stroke patients who had CTA ordered as a stroke code from September 2020 to December 2020. Data was collected on sex, age, Viz.AI LVO alert, and official Radiology review of CTA. Radiology read of CTA was considered gold standard. True negative was defined as Viz negative, Radiology negative. False positive was defined as Viz positive, Radiology negative. False negative was defined as Viz negative, Radiology positive. True positive was defined as Viz positive, Radiology positive. LVO was defined as occlusion of the intracranial carotid (ICAT) or MCA (M1 or M2 segment). Data was collected on performance of Viz.AI LVO alert, including sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Results: Among 282 consecutive suspected AIS patients with CTA analyzed by Viz.AI, the mean age was 61.9 years (range 19 to 96) and 152 (53.9%) were female. Viz LVO autodetection alerted for 60 patients (21.3%). Radiologist review reported 32 patients with LVO as follows: 12 (37.5%) M2, 16 (50%) M1, and 4 (12.5%) ICAT. The following were adjudicated: 219 true negatives, 31 false positive, 3 false negative, and 29 true positives. Sensitive was 90.6% and Specificity was 87.6%. PPV was 0.483 and NPV was 0.986. The 3 false negative patients all had M2 occlusions. The median time to alert was 10 min (range 7 to 656). Conclusions: In our series of AIS patients evaluated with CTA at an academic CSC, Viz.AI automated LVO detection performed well with a sensitivity of 90.6% and specificity of 87.5%, with a median time to alert of 10 minutes.

Purpose: To examine the three-dimensional foveal cone photoreceptor structure in a patient who had suffered laser pointer-induced retinal injury.Methods: Patient underwent standard fundus photography and clinical spectral domain optical coherence tomography imaging. High-resolution imaging was performed using an adaptive optics-optical coherence tomography-scanning laser ophthalmoscope.Results: Adaptive optics imaging revealed loss of inner and outer segments of cone photoreceptors whereas the anterior retinal layers appeared healthy. Analysis of cone topology showed an increase in Voronoi domain area and a less regular hexagonal packing structure closer to the lesion site.Conclusion: Exposure to laser pointer radiation, however brief, can result in damage to the retina. Here, repeated imaging nine months later showed a decrease in the size of the lesions (ranging from 3.7 to 23.9%) compared with the first time point. However, the longerterm prognosis is likely permanent scarring.

No abstract

No abstract

Pancreatic pseudocysts are a common complication of pancreatitis. However, mediastinal extension of a pseudocyst is rare and often presents with atypical symptoms. We present a case of mediastinal extension of a pancreatic pseudocyst in a 56-year-old woman with a history of alcohol-related chronic pancreatitis, who presented with acute on chronic epigastric abdominal pain and atypical chest pain. Serum lipase was elevated, and imaging by contrast-enhanced computed tomography (CT) demonstrated a paraesophageal fluid collection. This collection was continuous with a peripancreatic pseudocyst and extended into the posterior mediastinum via the esophageal hiatus. Mediastinal extension of a pancreatic pseudocyst was confirmed by magnetic resonance imaging (MRI). The patient was managed conservatively in the hospital with parenteral nutrition therapy, pain control, and close imaging observation. The patient was discharged home to continue conservative management and close imaging follow-up. An initial follow-up CT examination 8 weeks after discharge revealed interval decrease in the posterior mediastinal collection but also interval development of loculated left pleural and pericardial effusions.