CT venography for the diagnosis of postpartum venous thromboembolism: a prospective multi-center cohort study.

OBJECTIVES: To assess the role of CT venography (CTV) in the diagnosis of venous thromboembolism (VTE) during the postpartum period. MATERIALS AND METHODS: This multicenter prospective cohort study was conducted between April 2016 and April 2020 in 14 university hospitals. All women referred for CT pulmonary angiography (CTPA) for suspected pulmonary embolism (PE) within the first 6 weeks postpartum were eligible. All CTPAs were performed on multidetector CT machines with the usual parameters and followed by CTV of the abdomen, pelvis, and proximal lower limbs. On-site reports were compared to expert consensus reading, and the added value of CTV was assessed for both. RESULTS: The final study population consisted of 123 women. On-site CTPA reports mentioned PE in seven women (7/123, 5.7%), all confirmed following expert consensus reading, three involving proximal pulmonary arteries and four limited to distal arteries. Positive CTV was reported on-site in nine women, five of whom had negative and two indeterminate CTPAs, bringing the VTE detection rate to 11.4% (14/123) (95%CI: 6.4-18.4, p = 0.03). Expert consensus reading confirmed all positive on-site CTV results, but detected a periuterine vein thrombosis in an additional woman who had a negative CTPA, increasing the VTE detection rate to 12.2% (15/123) (95%CI: 7.0-19.3, p = 0.008). Follow-up at 3 months revealed no adverse events in this woman, who was left untreated. Median Dose-Length-Product was 117 mGy.cm for CTPA and 675 mGy.cm for CTPA + CTV. CONCLUSION: Performing CTV in women suspected of postpartum PE doubles the detection of venous thromboembolism, at the cost of increased radiation exposure. CLINICAL RELEVANCE STATEMENT: CTV can help in the decision-making process concerning curative anticoagulation in women with suspected postpartum PE, particularly those whose CTPA results are indeterminate or whose PE is limited to the subsegmental level. KEY POINTS: Postpartum women are at risk of pulmonary embolism, and CT pulmonary angiography can give equivocal results. CT venography (CTV) positivity increased the venous thromboembolism detection rate from 5.7 to 11.4%. CTV may help clinical decision-making, especially in women with indeterminate CTPA results or subsegmental emboli.

Uterine Sarcomas: Are There MRI Signs Predictive of Histopathological Diagnosis? A 50-Patient Case Series with Pathological Correlation.

PURPOSE: To make clear distinction between two radiological types of uterine sarcomas. METHODS: 50 preoperative MRI were analyzed retrospectively, blinded to histopathology: 11 endometrial stromal sarcomas (ESS), 19 leiomyosarcomas (LMS), 18 carcinosarcomas/malignant mixed Mullerian tumors (MMMT), and 2 smooth muscle tumors of uncertain malignant potential (STUMP). RESULTS: According to their locations, two radiological types of sarcomas were identified: type 1: intracavitary (ESS, MMMT) and type 2: intramyometrial (LMS, STUMP). In both types, all tumors displayed intermediate T2-weighted signal (p < 0.001) and high diffusion-weighted imaging (DWI) b1000 signal (p < 0.001). Dynamic contrast-enhanced (DCE) MRI showed intratumoral pathologic vessels (98%) and heterogeneity at venous phase (p < 0.001). In the type 1 subgroup, all tumors displayed local spread: invasion of junctional zone on T2-weighted imaging (T2WI), irregular margins on DWI, and disruption of arcuate arteries subendometrial ring on DCE-MRI. In the type 2 subgroup, all tumors displayed irregular margins on T2WI, DWI, and DCE-MRI. Tumor heterogeneity was due to necrosis (p < 0.001). Most commonly the tumor was single (61%). In both types, apparent diffusion coefficient (ADC) lesser than or equal to 0.86 × 10-3 mm2/s (sensitivity = 73%, specificity = 92%) was suggestive of malignancy. CONCLUSION: It may be feasible to get close to histological type of a uterine sarcoma based on our topographic classification into two radiological subgroups, corresponding to two kinds of diagnostic difficulties. Advances in knowledge. MRI signs suggestive of histopathological malignancy are identifiable, considering the triad T2WI/DWI/DCE-MRI, easily for type 1 but less easily for type 2; the threshold value for ADC is 0.86 × 10-3 mm2/s.

Early-phase myocardial uptake intensity of 99mTc-HMDP vs 99mTc-DPD in patients with hereditary transthyretin-related cardiac amyloidosis.

BACKGROUND: This study sought to compare the intensity of early-phase myocardial uptake of two phosphonate-based radiotracers, 99mTc-hydroxymethylene diphosphonate (HMDP) and 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD), in patients with hereditary transthyretin-related cardiac amyloidosis (TTR-CA). METHODS: Six patients with biopsy-proven diagnosis of TTR-CA and characteristic amyloid fibril composition underwent early-phase 99mTc-HMDP myocardial scintigraphy as part of their routine workup; they were later assessed by 99mTc-DPD scintigraphy after having signed informed written consent. Heart-to-mediastinum-ratio was measured at both time points as well as regional distribution on 17-segment analysis. RESULTS: All patients had an H/M ratio >1.28 on both imaging. 99mTc-DPD uptake was slightly higher than 99mTc-HMDP uptake in 3 patients, but no statistical difference was found (P = 0.13). Regional distribution of the two radiotracers was well correlated on bull's eyes analysis, with only slight underestimation of 99mTc-DPD uptake in the anterior/apical segments, compared with 99mTc-HMDP. CONCLUSION: 99mTc-HMDP and 99mTc-DPD show comparable myocardial uptake intensity on early-phase scintigraphy and can be used alternatively for the diagnosis of TTR-CA.