Ophthalmic artery occlusion after Pipeline Embolization Device placement with reconstitution of flow via an endoleak: a report of two cases.

The Pipeline Embolization Device (PED) is a flow diverting stent used in the treatment of a wide variety of intracranial aneurysms. The device differs from traditional stents used in stent-assisted coil embolization in that it has a tighter lattice structure with smaller cell sizes designed specifically to disrupt blood flow into aneurysms rather than only to retain coils within aneurysms. While the PED has been shown to be safe and effective, it has a unique risk profile that includes side branch and perforator vessel occlusion. Side branch occlusion in particular has been noted in several articles to occur at a relatively high rate with coverage of the ophthalmic artery origin by the PED. In this series, we present two cases of ophthalmic artery occlusion after PED placement with reconstitution of flow via an endoleak.

Variance owing to observer, repeat imaging, and fundus camera type on cup-to-disc ratio estimates by stereo planimetry.

OBJECTIVE: To determine and compare variance components in linear cup-to-disc ratio (LCDR) estimates by computer-assisted planimetry by human experts, and automated machine algorithm (digital automated planimetry). DESIGN: Prospective case series for evaluation of planimetry. PARTICIPANTS: Forty-four eyes of 44 consecutive patients from the outpatient Glaucoma Service at University of Iowa with diagnosis of glaucoma or glaucoma suspect were studied. METHODS: Six stereo pairs of optic nerve photographs were taken per eye: 3 repeat stereo pairs using simultaneous fixed-stereo base fundus camera (Nidek 3Dx) and another 3 repeat stereo pairs using sequential variable-stereo base fundus camera (Zeiss). Each optic disc stereo pair was digitized and segmented into cup and rim by 3 glaucoma specialists (computer-assisted planimetry) and using a computer algorithm (digital automated planimetry), and LCDR was calculated for each segmentation (either specialist or algorithm). A linear mixed model was used to estimate mean, SD, and variance components of measurements. MAIN OUTCOME MEASURES: Average LCDR, interobserver, interrepeat, intercamera coefficients of variation (CV) of LCDR and their 95% tolerance limits. RESULTS: There was a significant difference in LCDR estimates among the 3 glaucoma specialists. The interobserver CV of 10.65% was larger than interrepeat (6.7%) or intercamera CV (7.6%). For the algorithm, the LCDR estimate was significantly higher for simultaneous stereo fundus images (Nidek, mean: 0.66) than for sequential stereo fundus images (Zeiss, mean: 0.64), whereas interrepeat CV for Nidek (4.4%) was lower than Zeiss (6.36%); the algorithm's interrepeat and intercamera CV were 5.47% and 7.26%, respectively. CONCLUSIONS: Interobserver variability was the largest source of variation for glaucoma specialists, whereas their interrepeat and intercamera variability is comparable with that of the algorithm. DAP reduces variability on LCDR estimates from simultaneous stereo images, such as the Nidek 3Dx.

Investigating connectivity between the cerebellum and thalamus in schizophrenia using diffusion tensor tractography: a pilot study.

Connections of the cortical-thalamic-cerebellar-cortical regions provide a framework for studying the neural substrates of schizophrenia. A novel diffusion tensor tractography method was used to evaluate the differences in white matter connectivity between 12 patients with schizophrenia and 10 controls. For the tract tracing, we focused on the connection between the cerebellum and the thalamus. Fractional anisotropy (FA) measures along the fiber tracks were compared between patients and the control sample. Fiber tracts located between the cerebellar white matter and the thalamus exhibit a reduced FA in patients with schizophrenia in comparison with controls. The FA values along the defined fiber tracts were not overall reduced but exhibited a reduction in the anisotropy in the region in the superior cerebellar peduncles projecting towards the red nucleus.