RESUMEN
RATIONALE AND OBJECTIVES: Defacing research MRI brain scans is often a mandatory step. With current defacing software, there are issues with Windows compatibility and researcher doubt regarding the adequacy of preservation of brain voxels in non-T1w scans. To address this, we developed PyFaceWipe, a multiplatform software for multiple MRI contrasts, which was evaluated based on its anonymisation ability and effect on downstream processing. MATERIALS AND METHODS: Multiple MRI brain scan contrasts from the OASIS-3 dataset were defaced with PyFaceWipe and PyDeface and manually assessed for brain voxel preservation, remnant facial features and effect on automated face detection. Original and PyFaceWipe-defaced data from locally acquired T1w structural scans underwent volumetry with FastSurfer and brain atlas generation with ANTS. RESULTS: 214 MRI scans of several contrasts from OASIS-3 were successfully processed with both PyFaceWipe and PyDeface. PyFaceWipe maintained complete brain voxel preservation in all tested contrasts except ASL (45%) and DWI (90%), and PyDeface in all tested contrasts except ASL (95%), BOLD (25%), DWI (40%) and T2* (25%). Manual review of PyFaceWipe showed no failures of facial feature removal. Pinna removal was less successful (6% of T1 scans showed residual complete pinna). PyDeface achieved 5.1% failure rate. Automated detection found no faces in PyFaceWipe-defaced scans, 19 faces in PyDeface scans compared with 78 from the 224 original scans. Brain atlas generation showed no significant difference between atlases created from original and defaced data in both young adulthood and late elderly cohorts. Structural volumetry dice scores were ≥ 0.98 for all structures except for grey matter which had 0.93. PyFaceWipe output was identical across the tested operating systems. CONCLUSION: PyFaceWipe is a promising multiplatform defacing tool, demonstrating excellent brain voxel preservation and competitive defacing in multiple MRI contrasts, performing favourably against PyDeface. ASL, BOLD, DWI and T2* scans did not produce recognisable 3D renders and hence should not require defacing. Structural volumetry dice scores (≥ 0.98) were higher than previously published FreeSurfer results, except for grey matter which were comparable. The effect is measurable and care should be exercised during studies. ANTS atlas creation showed no significant effect from PyFaceWipe defacing.
RESUMEN
The susceptibility of the undescended testis to malignant transformation is well documented. The most common location of the undescended testis is within the inguinal canal, with only a minority located within the abdominal cavity. When a testicular mass develops, the risk of torsion increases. We describe a large intra-abdominal testicular seminoma that had undergone torsion, rupture and haemorrhage, presenting as an acute abdomen. A 30 year old man presented to the emergency department with right iliac fossa pain. Computed tomography in the emergency department showed haemoperitoneum and a torted large left testicular mass, likely malignant. The patient underwent laparotomy and excision of the mass. Histologic examination revealed a grossly enlarged seminomatous testis which had torted and ruptured. While pre-operative imaging diagnosis of an intra-abdominal testicular seminoma has been published, reports are few. To the best of the author's knowledge pre-operative imaging diagnosis of a malignant testicular mass with torsion and intra-abdominal haemorrhage presenting as an acute abdomen has not been described before.