Khandelwal, Ashish

Renovascular hypertension is the most common cause of secondary hypertension, and radiologist awareness of the various imaging appearances and various causes is crucial for accurate diagnosis and guiding treatment.

Alcohol use disorder is linked to a multitude of diseases and disorders, many of which can be diagnosed with imaging techniques such as US, CT, and MRI, enabling early detection and potentially preventing further damage and improving outcomes.

ABSTRACTBackgroundWe aimed to determine the performance of postoperative computed tomography (CT) and upper gastrointestinal series (UGI) in patients who underwent surgery for a perforated peptic ulcer and to assess the yield of routine postoperative studies.MethodsRetrospective, single‐institution, chart‐review study of patients who underwent a repair of a perforated gastric or duodenal ulcer between August 2004 and September 2021 at Mayo Clinic, Rochester, Minnesota.ResultsWe identified a total of 240 patients, 28 (12%) were found to have leaks. When any of the four findings (extraluminal gas or fluid collection adjacent to the repair, worsening pneumoperitoneum, or enteral contrast extravasation) was present on postoperative CT scan (n = 116) it had sensitivity of 76% (95% CI 53%–90%), with a specificity of 90% (95% CI 84%–91%). Upper gastrointestinal series (UGI, n = 150) showed a sensitivity of 57% (95% CI 25%–84%) and a specificity of 99% (95% CI 96%–100%). UGI demonstrated higher specificity compared to CT (p < 0.01); there was no significant difference in sensitivity (p = 0.34). The findings from CT scans led to changes in management for a significantly greater number of patients compared to UGI (20% vs. 4%, p < 0.01). The diagnostic yield for leak identification was 3% for routine postoperative CT (n = 63) and 2% for routine UGI studies (n = 141).ConclusionsPostoperative CT is more likely to change management in patients who underwent repair of a perforated peptic ulcer compared to postoperative upper gastrointestinal series. The yield of routine postoperative studies is low, and their benefit is uncertain.

Gastrointestinal (GI) bleeding is the most common GI diagnosis leading to hospitalization within the United States. Prompt diagnosis and treatment of GI bleeding is critical to improving patient outcomes and reducing high healthcare utilization and costs. Radiologic techniques including computed tomography angiography, catheter angiography, computed tomography enterography, magnetic resonance enterography, nuclear medicine red blood cell scan, and technetium-99m pertechnetate scintigraphy (Meckel scan) are frequently used to evaluate patients with GI bleeding and are complementary to GI endoscopy. However, multiple management guidelines exist which differ in the recommended utilization of these radiologic examinations. This variability can lead to confusion as to how these tests should be used in the evaluation of GI bleeding. In this document, a panel of experts from the American College of Gastroenterology and Society of Abdominal Radiology provide a review of the radiologic examinations used to evaluate for GI bleeding including nomenclature, technique, performance, advantages, and limitations. A comparison of advantages and limitations relative to endoscopic examinations is also included. Finally, consensus statements and recommendations on technical parameters and utilization of radiologic techniques for GI bleeding are provided.

Background Due to their easy accessibility, CT scans have been increasingly used for investigation of gastrointestinal (GI) bleeding. Purpose To estimate the performance of a dual-phase, dual-energy (DE) GI bleed CT protocol in patients with overt GI bleeding in clinical practice and examine the added value of portal phase and DE images. Materials and Methods Consecutive patients with GI bleeding underwent a two-phase DE GI bleed CT protocol. Two gastroenterologists established the reference standard. Performance was estimated using clinical CT reports. Three GI radiologists rated confidence in GI bleeding in a subset of 62 examinations, evaluating first mixed kV arterial images, then after examining additional portal venous phase images, and finally after additional DE images (virtual non-contrast and virtual monoenergetic 50 keV images). Results 52 of 176 patients (29.5%) had GI bleeding by the reference standard. The overall sensitivity, specificity, and positive and negative predictive values of the CT GI bleed protocol for detecting GI bleeding were 65.4%, 89.5%, 72.3%, and 86.0%, respectively. In patients with GI bleeding, diagnostic confidence of readers increased after adding portal phase images to arterial phase images ( p = 0.002), without additional benefit from dual energy images. In patients without GI bleeding, confidence in luminal extravasation appropriately decreased after adding portal phase, and subsequently DE images ( p = 0.006, p = 0.018). Conclusion A two-phase DE GI bleed CT protocol had high specificity and negative predictive value in clinical practice. Portal venous phase images improved diagnostic confidence in comparison to arterial phase images alone. Dual-energy images further improved radiologist confidence in the absence of bleeding.