Intradural Lumbar Disc Herniation

Intradural lumbar disc herniation(ILDH) is a rare pathology. The pathogenesis of ILDH is not known with certainty. Adhesions between the ventral wall of the dura and the posterior longitudinal ligament(PLL) could act as a preconditioning factor. Diagnosis of ILDH is difficult and seldom suspected preoperatively. Prompt surgery is necessary because the neurologic prognosis appears to be closely related to preoperative duration of neurologic symptoms. Despite preoperatively significant neurological deficits, the prognosis following surgery is relatively good. We report on case of ILDH at L3/4 with differential diagnoses, and the possible pathogenic factors are discussed.

Transcranial Doppler and Cerebrospinal Fluid Flow Study in Normal Pressure Hydrocephalus

OBJECTIVE: The authors analyze prospectively the result of transcranial doppler(TCD) in normal pressure hydrocephalus and compared its cerebral blood flow parameters to radionuclide cerebrospinal fluid(CSF) flow study, postoperative brain computed tomography(CT) findings and clinical outcome, and studied the relationship betweeen cerebral hemodynamics and clinical performance. METHODS: Twenty five patients with hydrocephalus undertook pre- and post-operative TCD but only preoperative CSF flow study was performed. Mean flow velocity(Vm), pulsatility index(PI) and resistance index(RI) were assessed through TCD and changes in ventricle size and cortical gyral atrophy were checked through brain CT. RESULTS: Postoperative hydrocephalus showed an increase in Vm(ACA P=0.037, MCA P=0.034), decrease in PI(ACA P=0.019, MCA P=0.017) and decrease in RI (ACA P=0.017, MCA P=0.021) compared to preoperative TCD parameters in the postoperative improvement group. In the postoperative improvement group, postoperative TCD parameters correlated with CSF flow study grade (Vm: R2=-0.75, PI: R2=0.86, RI: R2=0.78) and ventriculocranial ratio change correlated with PI change (R2=0.73). The convexity gyral atrophy and initial TCD parameters showed close relationship to outcome. CONCLUSION: PI and RI can be used as an indicator of post operative prognosis, and with the addition of CSF flow study values, can also be used as a tool to predict pre-op and post-op patient status and successful shunt surgery.

First-Pass Perfusion Computed Tomography and Transcranial Doppler in Hydrocephalus / 대한뇌혈관외과학회지

OBJECTIVES: The aim of this study are clinical application of perfusion computed tomography (perfusion CT) in hydrocephalus and comparison its cerebral blood flow parameters with transcranial doppler (TCD) and clinical outcome. METHOD: 25 patients with hydrocephalus took pre- and postoperative perfusion CT and TCD. 15 patients without neurologic deficit were also examined with same protocol as a control. Blood flow parameters of perfusion CT, such as cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) were analyzed according to clinical status and postoperative outcome. So did the TCD parameters, mean flow velocity (mFv) and pulsatility index (PI) with regard to clinical outcome. RESULTS: Perfusion CT parameters of the hydrocephalus showed decrease in CBF (gray matter P=0.035, periventricular region P=0.042) and increase in MTT (gray matter P=0.039, periventricular region P=0.045) compared to control. In postoperative improvement group, there noted reversal of perfusion parameters close to those of the control. TCD parameters showed increase in mFv (P=0.047), and decrease in PI (P=0.042) in cases with improvement. CONCLUSION: Perfusion brain CT and TCD can used as clinically useful tools to predict the postoperative outcome on hydrocephalus.