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Background:Significant dural sinus injury occurs in 1.5- 5% of all head injuries and injury to superior sagittal sinus accounts for 70-80% of these. Its management is also a challenging issue to every neurosurgeon.Materials and Methods:In a period of one year (Aug 2011 to july2012) out of 549 cases of head injuries operated in our department analysis of 15 cases (2.73%) shown to have superior sagittal sinus injury. Three dimensional reconstruction of skull bone during CT scan helped us to diagnose possible dural sinus injury pre-operatively.Results:SSS injury was due to direct impact of fracture segment (5 cases), extension of fracture line over sinus area (4 cases) or due to coronal suture diastases (6 cases). Injury to anterior third of sagittal sinus occurred in 12 cases (80%) and injury to middle third occurred in 3 cases (20%). Small tear over superior sagittal sinus was found in 7 cases (46.66%) and was managed with Gelfoam® compression only and in two cases (13.33%) were large tear, which was managed with sinoraphy. In four cases (36.34%) hitch stitches over Gelfoam® to adjacent bone given and in rest two cases (13.33%) a strip of bone was left over the sinus area and bilateral hitch stitches were applied.Conclusion:Injury to SSS in traumatic head injury patient though rarely encountered during surgery, the management is challenging to every neurosurgeon. Preoperative suspicion and combination of surgical techniques rather than one single technique may be effective in decreasing the sinus related mortality rate.

Extradural hematoma (EDH) in absence of trauma is a rare entity with only few cases reported in literature. The various causes reported include: Vascular malformation of dura, coagulopathies, sinus infection, middle ear or orbital infection, and tumor. Occurrence of spontaneous EDH as a complication of sickle cell disease is even much rarer. We report a case with sickle cell disease who presented with spontaneous extradural and subgaleal hematomas following an episode of vaso-oclusive crisis. He was managed successfully with surgery. The association of epidural hematomas in sickling hemoglobinopathies is reviewed. In all cases, we noticed one episode of sickle cell crisis just before the occurrence of spontaneous EDH. Perhaps this crisis puts an extra demand over the hematopoietic skull tissue disrupting inner and outer skull margins leading to spontaneous EDH and subgaleal hematoma.

Thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) particles of a nearly constant swelling ratio and with polydispersity indices (PDIs) varying over a wide range (7.4% -48.9%) are synthesized to study the effects of polydispersity on the dynamics of suspensions of soft PNIPAM colloidal particles. The PNIPAM particles are characterized using dynamic light scattering (DLS) and scanning electron microscopy (SEM). The zero shear viscosity (η0) data of these colloidal suspensions, estimated from rheometric experiments as a function of the effective volume fraction φ ef f of the suspensions, increases with increase in φ ef f and shows a dramatic increase at φ ef f = φ0. The data for η0 as a function of φ ef f fits well to the Vogel-Fulcher-Tammann (VFT) equation. It is observed that increasing PDIs results in increasingly fragile supercooled liquid-like behavior, with the parameter φ0, extracted from the fits to the VFT equation, shifting towards higher φ ef f . The observed increase in fragility is attributed to the prevalence of dynamical heterogeneities (DHs) in these polydisperse suspensions, while the simultaneous shift in φ0 is ascribed to the decoupling of the dynamics of the smallest and largest particles. Finally, it is observed that the intrinsic nonlinearity of these suspensions, estimated at the third harmonic near φ0 in Fourier transform oscillatory rheological experiments, increases with increase in PDIs. Our results are in agreement with theoretical predictions and simulation results for polydisperse hard sphere colloidal glasses and clearly demonstrate that jammed suspensions of polydisperse colloidal particles can be effectively fluidized with increasing PDIs. Suspensions of these particles are therefore excellent candidates for detailed experimental studies of the effects of polydispersity on the dynamics of glass formation.