Imaging Findings in Transgender Patients after Gender-affirming Surgery.

Gender-affirming surgeries expand the options for physical transition among transgender patients, those whose gender identity is incongruent with the sex assigned to them at birth. Growing medical insight, increasing public acceptance, and expanding insurance coverage have improved the access to and increased the demand for gender-affirming surgeries in the United States. Procedures for transgender women, those patients with feminine gender identity, include breast augmentation using implants and genital reconstruction with vaginoplasty. Some transgender women receive medically unapproved silicone injections for breast augmentation or other soft-tissue contouring procedures that can lead to disfigurement, silicone pulmonary embolism, systemic reactions, and even death. MRI is preferred over CT for postvaginoplasty evaluation given its superior tissue contrast resolution. Procedures for transgender men, patients with a masculine gender identity, include chest masculinization (mastectomy) and genital reconstruction (phalloplasty or metoidioplasty, scrotoplasty, and erectile device implantation). Urethrography is the standard imaging modality performed to evaluate neourethral patency and other complications, such as leaks and fistulas. Despite a sizeable growth in the surgical literature about gender-affirming surgeries and their outcomes, detailed descriptions of the imaging features following these surgeries remain sparse. Radiologists must be aware of the wide variety of anatomic and pathologic changes unique to patients who undergo gender-affirming surgeries to ensure accurate imaging interpretation. Online supplemental material is available for this article. ©RSNA, 2019.

Imaging features of low-grade central osteosarcoma of the long bones and pelvis.

PURPOSE: To determine the age and gender distribution and imaging features of low-grade central osteosarcoma (LGCOS) of the long bones and pelvis and to discuss our findings in the context of lesions for which LGCOS has been mistaken. MATERIALS AND METHODS: We reviewed 99 cases of LGCOS collected between 1919 and 2002 from our institution and pathology consultation files. Adequate imaging was available in 70 cases (36 radiographs only, 17 radiographs/CT, 12 radiographs/MRI, 2 radiographs/CT/MRI, 2 CT only, 1 MRI only, 5 bone scans). RESULTS: Patient average age was 30.1+/-14.2 years, with a slight female predominance. The femur and tibia were the most common long bones involved (29 and 20 each) with the majority of these tumors arising around the knee, followed by the fibula, radius, humerus and ulna (four, three, two and one case each). Flat bones were involved in six cases (three pelvis, one rib, two scapulae). Short tubular bones were involved in five cases (two metatarsal, two phalanges, one clavicle). The lesion extended to the end of the affected long bone in 22 of 59 cases. Lesions were large at presentation (mean 7.9+/-4.6 cm, range 2-24). Four radiographic patterns were identified: lytic with varying amounts of thick and coarse trabeculation ( n=22), predominantly lytic with few thin, incomplete trabecula ( n=21), densely sclerotic ( n=17) and mixed lytic and sclerotic ( n=10). Lesions were benign-appearing overall with focally aggressive features. CT or MRI demonstrated cortical breech or extension into the soft tissues in all cases. CONCLUSIONS: LGCOS has a variable appearance on radiographs. A frequent pattern is a slow-growing large intracompartmental fibro-osseous lesion with varying amounts of septal ossification associated with focal areas of aggression. A homogeneously sclerotic pattern was also noted. Imaging with CT or MRI was helpful in every instance in our series in identifying areas of soft tissue extension or cortical disruption suggestive of a low-grade malignancy.

Comparison of MS-325- and gadodiamide-enhanced MR venography of iliocaval veins.

PURPOSE: To compare conventional extracellular and blood-pool magnetic resonance (MR) contrast agents in "indirect" contrast-enhanced three-dimensional (3D) MR venography of the iliocaval veins. MATERIALS AND METHODS: Twenty-nine gadodiamide-enhanced 3D MR (Gd-MR) angiography studies and 12 MS-325-enhanced 3D MR (MS-325-MR) angiography studies were reviewed retrospectively. Abnormalities of the inferior vena cava (IVC) or iliac veins were not suspected before MR imaging. The MR angiography studies were reviewed with and without subtraction. Diagnostic conspicuity and subjective contrast of the various iliocaval venous segments (suprarenal IVC, infrarenal IVC, and iliac veins) and the presence of artifacts were subjectively scored by two blinded observers. RESULTS: In the Gd-MR angiography group, the infrarenal IVC and iliac veins were visualized with good conspicuity in only 55% of segments compared to 92%-100% of segments in the MS-325-MR angiography group. Although subtraction improved subjective conspicuity and contrast relative to background in the Gd-MR angiography group, it resulted in increased artifacts and luminal blurring. Subtraction offered little diagnostic advantage in the MS-325-MR angiography group. CONCLUSION: Indirect contrast-enhanced 3D MR venography with use of MS-325 offered significantly improved diagnostic conspicuity and contrast in iliocaval venous opacification compared to gadodiamide-enhanced studies.

Value of MR angiography before percutaneous transluminal renal artery angioplasty and stent placement.

PURPOSE: To determine the benefit of preprocedural three-dimensional gadolinium (Gd)-enhanced magnetic resonance (MR) angiography before percutaneous transluminal renal artery angioplasty and stent placement (PTRA/S) in terms of procedural success, iodinated contrast material load, and procedure duration. MATERIALS AND METHODS: Over an 18-month period, 39 patients underwent attempted percutaneous renal angioplasty with or without stent placement. A total of 48 renal arteries were treated (40 cases of atherosclerosis, one of stent restenosis, five of fibromuscular dysplasia, and two of transplant stenosis). Preprocedural Gd-enhanced MR angiography was available in 16 procedures (41%). Procedural outcome, complications, iodinated contrast material load, number of diagnostic angiographic runs, and total procedure duration were each compared between two subgroups: patients who had preprocedural Gd-enhanced MR angiography ("prior MR angiography group") and those who did not ("no MR angiography" group). RESULTS: All procedures were technically successful. The two groups were equivalent in terms of age and disease pattern. However, technical complexity of the procedure was judged to be high in five of 16 procedures in the prior MR angiography group compared to three of 23 procedures in the no MR angiography group (P =.16). Bilateral or dual interventions were performed in six of 16 procedures in the prior MR angiography group compared to three of 23 in the no MR angiography group (P =.075). Iodinated contrast material load was significantly lower in the prior MR angiography group than in the no MR angiography group (68.7 mL +/- 28.4 vs 119.1 mL +/- 49.2 mL;P <.0008). The number of diagnostic angiographic runs before interventions were also significantly lower in the prior MR angiography group (1.2 +/- 0.4 vs 2.6 +/- 0.7; P <.0001). Overall procedure duration was comparable between the two groups (91.9 +/- 47.8 vs 112.2 +/- 49.4;P =.2). CONCLUSION: Preprocedural planning with use of Gd-enhanced MR angiography significantly reduces the iodinated contrast material requirement during percutaneous renal artery interventions. It can also significantly shorten procedure duration.