Differential tractography and whole brain connectometry in primary motor area gliomas resection: A feasibility study.

OBJECTIVE: Establish the evolution of the connectome before and after resection of motor area glioma using a comparison of connectome maps and high-definition differential tractography (DifT). METHODS: DifT was done using normalized quantitative anisotropy (NQA) with DSI Studio. The quantitative analysis involved obtaining mean NQA and fractional anisotropy (FA) values for the disrupted pathways tracing the corticospinal tract (CST), and white fiber network changes over time. RESULTS: We described the baseline tractography, DifT, and white matter network changes from two patients who underwent resection of an oligodendroglioma (Case 1) and an IDH mutant astrocytoma, grade 4 (Case 2). CASE 1: There was a slight decrease in the diffusion signal of the compromised CST in the immediate postop. The NQA and FA values increased at the 1-year follow-up (0.18 vs. 0.32 and 0.35 vs. 0.44, respectively). CASE 2: There was an important decrease in the immediate postop, followed by an increase in the follow-up. In the 1-year follow-up, the patient presented with radiation necrosis and tumor recurrence, increasing NQA from 0.18 in the preop to 0.29. Fiber network analysis: whole-brain connectome comparison demonstrated no significant changes in the immediate postop. However, in the 1-year follow up there was a notorious reorganization of the fibers in both cases, showing the decreased density of connections. CONCLUSIONS: Connectome studies and DifT constitute new potential tools to predict early reorganization changes in a patient's networks, showing the brain plasticity capacity, and helping to establish timelines for the progression of the tumor and treatment-induced changes.

Ventriculo-atrial shunt. Comparison of an ultrasound-guided peel-away technique versus conventional technique in the management of normal pressure hydrocephalus: A retrospective cohort.

BACKGROUND: Normal pressure hydrocephalus (NPH) is a common neurodegenerative syndrome among the elderly characterized by ventriculomegaly and the classic triad of symmetric gait disturbance, cognitive decline and urinary incontinence. To date, the only effective treatment is a cerebrospinal fluid shunting procedure that can either be ventriculo-atrial, ventriculo-peritoneal, or lumbo-peritoneal shunt. The conventional ventriculo-atrial shunt uses venodissection, whereas the peel-away is a percutaneous ultrasound (US)-guided technique that shows some advantages over conventional technique. We sought to compare perioperative complication rates, mean operating time and clinical outcomes for both techniques in NPH patients at our institution. METHODS: A retrospective cohort-type analytical study was conducted, using clinical record data of patients diagnosed with NPH and treated at our center from January 2009 to September 2019. Parameters to be compared include: Perioperative complication rates, intraoperative bleeding, mortality, and mean operating time. Perioperative complication rates are those device-related such as shunt infection, dysfunction, and those associated with the procedure. Complications are further classified in immediate (occurring during the first inpatient stay), early (within the first 30 days of surgery), and late (after day 30 of surgery). RESULTS: A total of 123 patients underwent ventriculo-atrial shunt. Eighty-two patients (67%) underwent conventional venodissection technique and 41 patients (33%) underwent a peel-away technique. Immediate complications were 3 (3.6%) and 0 for conventional and peel-away groups, respectively. Early complications were 0 and 1 (2.4%) for conventional and peel-away groups, respectively. Late complications were 5 (6.1%) and 2 (4.9%) for conventional and peel-away groups, respectively. Mean operating time was lower in the peel-away group (P = 0.0000) and mortality was 0 for both groups. CONCLUSION: Ventriculo-atrial shunt is an effective procedure for patients with NPH. When comparing the conventional venodissection technique with a percutaneous US-guided peel-away technique, the latter offers advantages such as shorter operating time and lower perioperative complication rates.