Delayed Gadolinium Leakage in Ocular Structures: A Potential Marker for Age- and Vascular Risk Factor-Related Small Vessel Disease?

BACKGROUND: Gadolinium leakage in ocular structures (GLOS) was recently observed in fluid-attenuated inversion recovery (FLAIR) images obtained the day after an initial gadolinium injection in stroke patients. The specificity of GLOS to stroke and its mechanisms remain unclear. OBJECTIVE: We investigated the factors associated with GLOS in a cohort of patients presenting with acute neurological deficits. MATERIALS AND METHODS: This retrospective study included consecutive patients admitted to our stroke unit for acute neurological deficit between July 2017 and August 2018 who underwent baseline brain magnetic resonance imaging with the injection of a macrocyclic gadolinium agent and another scan without injection within 72 hours. The patients were separated into a stroke group and a stroke mimic group based on diffusion-weighted images. Gadolinium leakage in ocular structures was defined as a bright signal in the vitreous in follow-up FLAIR compared with baseline FLAIR (pregadolinium). Clinical data were collected together with imaging features from the baseline scans, including the volume of the infarct and of hypoperfusion if applicable, white matter hyperintensities, the number of lacunes, and the number of microbleeds, which were combined to yield a small vessel disease (SVD) score. We compared the prevalence of GLOS in both groups using the χ2 test. In the entire cohort, univariate and multivariate regression models were used to test the associations between GLOS and the collected data. RESULTS: Among the 467 patients included in the study, GLOS was observed in similar proportions in the stroke group (32.2%, 136/422) and the stroke mimic group (28.9%, 13/45; mean difference, 3.3%; 95% confidence interval, -10.9 to 17.6; P = 0.65). In univariate analysis, GLOS was associated with older age, increased prevalence of vascular risk factors, brain imaging features of SVD (white matter hyperintensities, lacunes, microbleeds), as well as with impairment of renal function and increased dose of gadolinium. No associations were found with factors related to stroke, such as its volume, acute treatment, or rate of recanalization. Multivariate analyses showed that aging (P < 0.001), diabetes (P = 0.010), severe renal failure (P = 0.004), and increased dose of gadolinium (P < 0.001) were independent contributors to GLOS. CONCLUSIONS: Gadolinium leakage in ocular structures, which occurs more commonly at higher concentrations of gadolinium, is not specific to stroke and may represent increased permeability of the blood-retinal barrier associated with age- and vascular risk factor-related SVD.

Minimally Invasive Plate Osteosynthesis for Extra-articular Distal Radius Fracture in Postmenopausal Women: Longitudinal versus Transverse Incision.

Background This work aimed to compare two mini-invasive palmar approaches (longitudinal and transverse) to osteosynthesize fractures of the distal radius. The main hypothesis was that the longitudinal technique gave smaller incisions. The secondary hypothesis was that the longitudinal technique would be better for the recovery of pain, functional scores, strength, and mobility. Materials and Methods The series included 30 extra-articular distal radius fractures in 30 patients (average age: 74 years) fixed with volar locking plate using a mini-invasive technique. Fifteen of these patients had a single longitudinal surgical approach (Group I), and 15 had a transverse approach that was completed with a longitudinal incision for the proximal screws (Group II). Results The combined average incision size was 14.73 mm in Group I and 19.8 mm in Group II. After 6 months, the pain was on average 1.4/10 (Group I) and 0.46/10 (Group II), the quick Disability of the Arm, Shoulder, and Hand was 13.63/100 (Group I) and 2.8/100 (Group II), Patient-Related Wrist Evaluation was 11.8/100 (Group I) and 5.97/100 (Group II), grip strength was 81.06% (Group I) and 72.13% (Group II), flexion was 88.13% (Group I) and 75% (Group II), extension was 86% (Group I) and 64.6% (Group II), ulnar inclination was 89% (Group I) and 78.67% (Group II), radial inclination was 89.73% (Group I) and 79.93% (Group II), pronation was 96.67% (Group I) and 81.46% (Group II), and supination was 91.93% (Group I) and 79.87% (Group II). Clinical Relevance The longitudinal technique gave smaller incisions than the transverse technique. Among the secondary hypotheses, all the variables were better with the longitudinal technique, except the pain, although without any significant difference.

T2 Star-weighted Angiography (SWAN) Allows to Concomitantly Assess the Prostate Contour While Detecting Fiducials Before MR-based Intensity-modulated Radiation Therapy in Prostate Carcinoma.

PURPOSE: To evaluate the performance of T2 star-weighted angiography (SWAN) to concomitantly assess the prostate contour while detecting fiducials before magnetic resonance (MR)-based intensity-modulated radiation therapy (IMRT) in prostate carcinoma. MATERIALS AND METHODS: Forty patients (mean age: 73.1 ± 7.5 years; average Gleason score: 7 ± 1; average prostate-specific antigen: 14.7 ± 11.6 ng/mL) underwent MR and computed tomography imaging before fiducial-based IMRT. MR protocol included SWAN, T2-weighted (T2w) and diffusion-weighted imaging in a first group (n = 20) and SWAN, T2w and T2-star weighted imaging in a second group (n = 20). In group 1, the depiction of fiducials, image sharpness and visibility of prostate boundaries were independently evaluated by 2 readers on SWAN, T2w or diffusion-weighted images. In group 2, a similar evaluation was performed by 2 other readers on SWAN and T2-star images only. Depiction of fiducials was compared to computed tomography findings. RESULTS: The median scores of visibility of prostate boundaries, image sharpness and depiction of fiducials by SWAN were above average to excellent for all readers. In group 1, readers correctly located 56 of 57 (98.2%) and 47 of 57 (82.5%) fiducials, respectively; and 50 of 51 (98%), and 48 of 51 (88.2%) fiducials in group 2, respectively. CONCLUSION: By allowing adequate visualization of the prostate boundaries and high depiction of fiducial markers concomitantly, SWAN might be used for treatment planning of IMRT. The use of this sequence might simplify the registration process and limit any errors associated with image fusion.

Is Multiparametric MRI Useful for Differentiating Oncocytomas From Chromophobe Renal Cell Carcinomas?

OBJECTIVE: The purpose of this study was to retrospectively evaluate the diagnostic accuracy of multiparametric MRI to differentiate oncocytoma from chromophobe renal cell carcinoma (RCC). MATERIALS AND METHODS: In this retrospective study, 26 histologically confirmed oncocytomas and 16 chromophobe RCCs that underwent full MRI examination were identified in 42 patients (25 men and 17 women) over a 6-year period. Demographic data were recorded. Double-echo chemical-shift, dynamic contrast-enhanced T1- and T2-weighted images, and apparent diffusion coefficient (ADC) maps were reviewed independently by two radiologists blinded to pathologic results. Signal-intensity index (SII), tumor-to-spleen signal-intensity ratio, ADC ratio, three wash-in indexes, and two washout indexes were calculated and compared using univariate and ROC analyses. Sensitivity and specificity analyses were performed to calculate diagnostic accuracy. RESULTS: All carcinomas and nine oncocytomas were resected; the remaining 17 oncocytomas were biopsied. Patient age (for oncocytomas: mean, 68.2 years; range, 43-84 years; for RCCs: mean, 60.8 years; range, 20-79 years) and tumor size (for oncocytomas: mean, 35.5 mm; range, 12-98 mm; for RCCs: mean, 37.2 mm; range, 9-101 mm) did not differ significantly across groups (p = 0.132 and 0.265, respectively). Good interobserver agreement was observed for all measurements but four. Oncocytomas presented significantly higher ADC (p = 0.002) and faster enhancement (p = 0.007-0.012) but lower SII (p = 0.03) than carcinomas. This combination provided sensitivity of 92.3% (24/26), specificity of 93.8% (15/16), and accuracy of 92.9% (39/42) for the detection of oncocytomas. CONCLUSION: Multiparametric MRI helps to accurately differentiate oncocytomas from chromophobe RCCs with high sensitivity and specificity.