Optimizing fibrin hydrogel toward effective neural progenitor cell delivery in spinal cord injury.

Transplantation of neural progenitor cell (NPC) possessing the potential to differentiate into neurons may guard against spinal cord injury (SCI)- associated neuronal trauma. We propose that autologous-like NPC may reduce post-transplant immune response. The study used the rat SCI model to prove this concept. For isolation and expansion of rat NPC for cell-based SCI therapy, thein vitroprotocol standardized with human NPC seemed suitable. The primary aim of this study is to select a cell/neural tissue-compatible biomaterial for improving NPC survivalin vivo. The composition of the fibrin hydrogel is adjusted to obtain degradable, porous, and robust fibrin strands for supporting neural cell attachment, migration, and tissue regeneration. This study employed NPC culture to evaluate the cytocompatibility and suitability of the hydrogel, composed by adding graded concentrations of thrombin to a fixed fibrinogen concentration. The microstructure evaluation by scanning electron microscope guided the selection of a suitable composition for delivering the embedded cells. On adding more thrombin, fibrinogen clotted quickly but reduced porosity, pore size, and fiber strand thickness. The high activity of thrombin also affected NPC morphology and thein vitrocell survival. The selected hydrogel carried viable NPC and retained them at the injury site post-transplantation. The fibrin hydrogel played a protective role throughout the transfer process by providing cell attachment sites and survival signals. The fibrin and NPC together regulated the immune response at the SCI site reducing ED1+ve/ED2+vemacrophages in the early period of 8-16 d after injury. Migration ofß-III tubulin+veneural-like cells into the fibrin-injected control SCI is evident. The continuous use of a non-neurotoxic fibrin matrix could be a convenient strategy forin vitroNPC preparation, minimally invasive cell delivery, and better transplantation outcome.

Compressive vertebral hemangiomas with neurological deficits: diagnosis, surgical strategies and long term outcome.

PURPOSE: Compressive vertebral hemangiomas with neurological deficits (CVHND) form a rare, unique subset of lesions comprising of differing clinico-imaging findings, pathologic behavior and treatment, when compared to the commoner and usually incidental intra-osseus vertebral hemangiomas (VH). Though various surgical strategies and a broad array of adjuncts have evolved and changed over the years, there is paucity of comprehensive data from sizeable series of such patients treated surgically with long term follow up. The purpose of this study is to device an optimum management strategy in CVHND based on our surgical experience. MATERIALS AND METHODS: The data from electronic medical records of 26 consecutive patients operated in our department from 2009 to 2019 were retrospectively analyzed. RESULTS: There were 11 males and 15 females with a mean age of 34.7 years. Neurological examination revealed paraparesis or paraplegia with myelopathy in all patients with Frankel score of B, C and D in 1 (3.9%), 11 (42.3%) and 14 (53.8%) patients respectively. Sixteen patients (61%) underwent laminectomy and gross total excision of extradural soft tissue component, 7 (27%) laminectomy with posterolateral fusion, three (12%) underwent additional anterior interbody support. The mean follow up was 72.4 months and at last follow-up 24 patients (92%) were Frankel E. Symptomatic recurrence was seen in two patients operated early in the series, they underwent re-surgery, gross total excision with posterolateral fusion, remaining neurologically intact at last follow up. CONCLUSIONS: Pre-operative embolization, surgical excision of extradural component and intra-operative vertebroplasty form the mainstay of treatment for CVHND. Instrumented posterolateral fusion with optional anterior interbody support accomplished through the same approach is required only in a minority of cases. The long-term outcome following timely and appropriate treatment is excellent. Anterior or anterolateral approaches for intervertebral support and radical procedures like total en-bloc spondylectomy (TES) are not usually required.

Symptomatic posterior fossa and supratentorial subdural hygromas as a rare complication following foramen magnum decompression for Chiari malformation Type I.

Symptomatic subdural hygroma due to foramen magnum decompression for Chiari malformation Type I is extremely rare. The authors present their experience with 2 patients harboring such lesions and discuss treatment issues. They conclude that the possibility of subdural hygromas should be considered in all patients presenting with increased intracranial tension following foramen magnum decompression for Chiari malformation Type I. Immediate neuroimaging and appropriate surgical intervention provides a good outcome.