Distribution of Lower Extremity Deep Vein Thrombosis and Implications for Limited Compression Ultrasound Examinations.

BACKGROUND: Limited compression bedside ultrasonography (LCUS) including two-point, three-point, and extended compression examinations have become increasingly popular among emergency physicians to assess for lower extremity deep venous thrombosis (DVT). OBJECTIVE: Our objective in this study was to determine the prevalence and distribution of lower extremity DVT in sites identified by complete duplex ultrasonography (CDUS) that may potentially be missed using limited compression ultrasonography techniques. METHODS: This was a retrospective, multicenter study conducted at 12 hospitals within the Northwell Health system over a span of 4 years. Study participants (emergency department patients) underwent CDUS to assess for possible DVT. Images were reviewed and interpreted by radiologists and vascular surgeons at each of the participating institutions. RESULTS: A total of 42,487 CDUS examinations were performed, of which 3383 were positive for DVT. DVTs were deemed to be acute in 2664 (79%) and chronic in the remaining 21% on the basis of comparison with previous studies and appearance of the vein. Of the acute DVTs, 136 (5.1%) were confined to the common femoral vein, 116 (4.4%) to the femoral vein, 8 (0.3%) to deep femoral vein, 213 (8.0%) to popliteal vein, and 934 (35.1) to calf veins alone. CONCLUSIONS: In our study, a significant number of DVTs were identified in sites that may have been potentially missed on LCUS examinations, thereby supporting the use of complete duplex ultrasonography when available.

Can obstructive urolithiasis be safely excluded on contrast CT? A retrospective analysis of contrast-enhanced and noncontrast CT.

PURPOSE: The aim of this study was to determine if contrast-enhanced CT can safely exclude obstructive urolithiasis in patients with flank plain. We performed a retrospective cohort analysis to compare the negative predictive values of contrast-enhanced and non-contrast CTs for the detection of obstructing urolithiasis. METHODS: Through report analysis, we identified all non-contrast and contrast-enhanced CT examinations of the abdomen and pelvis performed on adult patients in the emergency department at a single, multi-site academic medical institution in 2017 with an indication of flank pain. The prevalence of obstructive urolithiasis in each group was calculated. We subsequently analyzed 200 consecutive studies from each of these groups (reported negative for obstructive urolithiasis) for negative predictive value calculation. Follow up abdominal imaging within 7 days from original presentation was used as a reference standard for analysis. RESULTS: In the noncontrast group, 1 study out of 200 was false negative (negative predictive value = 99.5%). In the contrast-enhanced group, there were no false negatives (negative predictive value = 100%). The prevalence of obstructive urolithiasis was 44.0% (351/797) in the noncontrast group and 18.7% (86/459) in the contrast-enhanced group. CONCLUSION: Our results suggest that contrast-enhanced CT can safely exclude obstructing ureteral calculi in the setting of acute flank pain. This finding is of clinical relevance given the inherent benefit of IV contrast in diagnosing abdominopelvic pathology.

Highlights from the scientific and educational abstracts presented at the ASER 2016 annual scientific meeting and postgraduate course.

The annual meeting of the American Society of Radiology (ASER) took place in San Francisco, California on September 14 through September 17, 2016. Attendees represented the USA as well as international emergency radiology communities, including those from academic, private practice, and teleradiology settings. There were several "members in training" in attendance as well. The meeting again featured the "Trauma Head to Toe" 2-day didactic course, highlighting various important topics on imaging of traumatic injuries. Scattered throughout the 4 days were several poster and case of the day presentations, scientific sessions, and self-assessment modules. The following is a summary of the educational posters and scientific papers.

Highlights on novel imaging methods of pancreatic cancer.

Pancreatic cancer is the fourth leading cause of cancer deaths. Since the majority of patients present with incurable metastatic disease, novel imaging methods are needed to identify pancreatic cancer and assess response to therapy. Research presented at the 2013 American Society of Oncology (ASCO) Annual Meeting provided insight into potential imaging methods. We discuss Abstracts #4049, #TPS4144, #TPS4146, and #E15069 in this paper.

Utility of dual read in the setting of prostate MRI interpretation.

PURPOSE: The purpose of this study is to assess the utility of dual reader interpretation of prostate MRI in the evaluation/detection of prostate cancer, using the PI-RADS v2.1 scoring system. METHODS: We performed a retrospective study to assess the utility of dual reader interpretation for prostate MRI. All MRI cases compiled for analysis were accompanied with prostate biopsy pathology reports that included Gleason scores to correlate to the MRI PI-RADS v2.1 score, tissue findings and location of pathology within the prostate gland. To assess for dual reader utility, two fellowship trained abdominal imagers (each with > 5 years of experience) provided independent and concurrent PI-RADS v2.1 scores on all included MRI examinations, which were then compared to the biopsy proven Gleason scores. RESULTS: After application of inclusion criteria, 131 cases were used for analysis. The mean age of the cohort was 63.6 years. Sensitivity, specificity and positive/negative predictive values were calculated for each reader and concurrent scores. Reader 1 demonstrated 71.43% sensitivity, 85.39% specificity, 69.77% PPV and 86.36% NPV. Reader 2 demonstrated 83.33% sensitivity, 78.65% specificity, 64.81% PPV and 90.91% NPV. Concurrent reads demonstrated 78.57% sensitivity, 80.9% specificity, 66% PPV and 88.89% NPV. There was no statistically significant difference between the individual readers or concurrent reads (p = 0.79). CONCLUSION: Our results highlight that dual reader interpretation in prostate MRI is not needed to detect clinically relevant tumor and that radiologists with experience and training in prostate MRI interpretation establish acceptable sensitivity and specificity marks on PI-RADS v2.1 assessment.

Substantial interreader agreement for biopsy with reduction in biopsy rate: A multireader diagnostic performance study of ACR TI-RADS.

PURPOSE: To assess diagnostic performance of ACR TI-RADS in thyroid cancer detection and evaluate interobserver agreement among radiologists with lower interpreting experience. METHODS: Four radiologists retrospectively assessed 295 biopsied thyroid nodules from ultrasound studies performed between 2009 and 2019, blinded to histopathology. Diagnostic performance for cancer detection was determined individually, and interobserver agreement among four readers was evaluated with Fleiss kappa coefficient (ⱪ). RESULTS: 245 (83.1%) benign and 50 (16.9%) malignant nodules were evaluated. Diagnostic performance based on final TR level was consistent and without significant difference among four readers, with excellent sensitivity (≥98.0%) and negative predictive value (NPV) [≥94.4%] for TR levels 3 to 5. Diagnostic performance based on recommendation to biopsy has moderate sensitivity (≥62%) and high NPV (≥84.7%). Retrospective scoring with established ACR TI-RADS criteria would have substantially reduced the number of biopsies performed, with 63.2% of malignancy not biopsied meeting criteria for sonographic surveillance. Interobserver agreement on TI-RADS scoring for final TR level was fair (ⱪ = 0.39, 95% CI 0.32, 0.47), with substantial agreement for recommendation to biopsy (ⱪ = 0.64, 95% CI 0.58, 0.70). CONCLUSIONS: Substantial reduction in biopsy rate (up to 48%) would have been achieved using the ACR TI-RADS criteria, with 63% of malignancy not biopsied meeting criteria for sonographic surveillance. Interobserver agreement was fair for TI-RADS level scoring and substantial for recommendation to biopsy.

Complete testicular infarction secondary to epididymoorchitis and pyocele.

Epididymoorchitis is a relatively common urologic condition involving the scrotum which presents with unilateral pain and swelling. It is typically treated with antibiotics but can progress to complications such as scrotal pyocele. Global testicular infarction is an exceedingly rare but devastating complication of epididymoorchitis. Grey scale and color Doppler ultrasound demonstrate testicular hypovascularity with subsequent hypoechoic changes of the testicular parenchyma. Scrotal MRI shows T2 hyperintense changes through the testicle with nonenhancement of the testicular parenchyma post contrast, consistent with infarction. The cause of global infarction in epididymitis is uncertain but may be due to mixed arterial and venous insufficiency. This case illustrates a 41-year-old male that developed acute left testicular pain. Initial ultrasound showed an enlarged left testicle with hyperemia. The patient's symptoms progressed and a scrotal MRI demonstrated a lack of left testicular enhancement consistent with global infarction, as well as an adjacent pyocele.

Utility of ultrasound after a negative CT abdomen and pelvis in the emergency department.

PURPOSE: The purpose of this study is to assess the utility of an abdominal and/or pelvic ultrasound (US) performed within 24 h after a negative CT of the abdomen and pelvis (CTAP) in the emergency department (ED). The secondary endpoint is to assess whether there is a significant increase in length of stay (LOS) in the ED due to immediate US reimaging. METHOD: We reviewed the imaging reports of 335 patients over the course of 3 years in our ED who had an US within 24 h after a negative CTAP. We then assessed type of US and whether the US showed any acute findings. We also evaluated LOS in the ED. RESULTS: Out of 335 patients, there were only three US cases suspicious for acute surgical pathology (3/335 or 0.9%). On 30-day clinical follow-up, only one of the three cases was confirmed as cholecystitis on pathology. The most common non-surgical findings on US not initially reported on CTAP were ovarian cysts (29/83) and gallstones (9/83). Additionally, the LOS for patients who received both a CTAP and US was 119 min longer than patients who only received a CTAP. CONCLUSION: US abdomen and/or pelvis reimaging within 24 h following a negative CTAP is unlikely to change surgical management in the acute setting. US reimaging can still be useful in diagnosing non-surgical pathology, which could serve to explain the patient's pain. US reimaging after negative CTAP is associated with an average increase in the ED LOS.

No catheter angiography is needed in patients with an obscure acute gastrointestinal bleed and negative CTA.

PURPOSE: To evaluate the negative predictive power of computed tomography angiography (CTA) for the identification of obscure acute gastrointestinal (GI) bleeding (GI bleeding not visualized/treated by endoscopy) on subsequent mesenteric angiography (MA) with the intention to treat. MATERIALS AND METHODS: A retrospective chart review of patients was performed who underwent mesenteric angiography for the evaluation/treatment of acute GI bleeding between November 2012 and July 2016. Patients with negative CTA examinations that proceeded to MA were identified. Negative predictive value (NPV) was calculated. RESULTS: 20 patients (14 male, 6 female; average age: 73.1±12.8years) underwent 20 negative CTA examinations for the evaluation and treatment of GI bleeding followed by mesenteric angiography. Eighteen of 20 patients had negative subsequent MA (negative predictive value, NPV=90%). Both false negative cases were upper GI bleed (vs 0 lower GI bleed); this difference was significant (p<0.05). CONCLUSIONS: The high NPV of CTA for the evaluation of GI bleeding suggests utility for excluding patients that are unlikely to benefit from MA and subsequent endovascular therapy. CTA may be considered for the first line diagnostic study for the evaluation of obscure GI bleeding.

A Private Investigation: Radiologic-Pathologic Correlation of Testicular Tumors.

To review the classification of testicular tumors, describe the sonographic and pathologic features of each tumor type, and discuss the mimics, diagnostic pitfalls, and management of testicular tumors. Method consists of pictorial review. We review sonographic and pathologic findings of several testicular tumors and tumorlike entities. Although ultrasound is the first-line imaging modality to differentiate between intratesticular and extratesticular location of an intrascrotal mass, it is not specific for intratesticular lesion characterization. Therefore, correlation with histology sampling is often necessary.