Chiari malformation: CSF flow dynamics in the craniocervical junction and syrinx.

BACKGROUND: A CSF flow study in patients with Chiari malformation (ChM) who undergo craniocervical junction decompression (CCJD). METHODS: Using spatial modulation of magnetization (SPAMM), cerebrospinal fluid (CSF) flow velocities were measured at the prepontine (PP), anterior cervical (AC), and posterior cervical (PC) subarachnoid spaces (SAS) in healthy subjects (n = 11) and patients with Chiari malformation (ChM) before and/or after CCJD (n = 15). In the syringes, the intrasyrigeal pulsatile CSF motion was estimated qualitatively as present or absent. FINDINGS: In normal subjects, the mean CSF velocities were 2.4 +/- 0.2 cm/s (PP), 2.8 +/- 0.3 cm/s (AC), and 2.4 +/- 0.2 cm/s (PC). Velocities were significantly lower than normal in patients with ChM prior to CCJD, reduced by 38%, 25%, and 79% in the 3 regions, respectively (P<0.001). Post-CCJD, velocities were 20% (PP), 100% (AC), and 40% (PC) greater than preoperatively (P<0.001). CONCLUSIONS: In ChM, the posterior cervical CSF flow velocity was low, increased minimally after CCJD and, by itself, had limited predictive value. Post-CCJD, an increase of the sum of anterior and posterior cervical CSF flow velocities by more than 20% consistently preceded or coincided with marked headache improvement. After CCJD, the finding that the intrasyringeal CSF pulsatile motion had become absent was an earlier and more sensitive predictor of motor or sensory improvement than a reduction in syrinx's size. SPAMM can be used to assess whether CCJD has restored CSF flow, predict outcome and provide pathophysiological insights in ChM and syringomyelia.

Stroke incidence and case fatality in southern Greece: the Arcadia stroke registry.

BACKGROUND AND PURPOSE: For Greece, information on incidence of stroke and distribution of type of stroke has not been reported. We determined the incidence of first-ever stroke in men and women, the incidence of stroke by type, and the associated case fatality. METHODS: A population-based registry was established in the Arcadia province, located in eastern central Peloponessos, in the southern part of Greece. Between November 1, 1993, and October 31, 1995, all subjects with a first-ever stroke were identified. For case ascertainment, information from death certificates, hospital records, public health centers, and general practitioners was used. RESULTS: During a 24-month period, 555 subjects with a first-ever stroke were registered. The incidence rates (per 100 000) by age group (18 to 34, 35 to 44, 45 to 54, 55 to 64, 65 to 74, 75 to 84, >/=85 years) for men were 5, 31, 113, 240, 662, 1275, and 3218, respectively. For women, the rates were 11, 18, 48, 196, 478, 1166, and 2137, respectively. Age- and sex-standardized to the European population, the annual incidence rate for subjects aged 45 to 84 years was 319.4/100 000 (95% CI, 283 to 356). In men, cerebral infarction was diagnosed in 81% of cases, intracerebral hemorrhage in 16%, and subarachnoid hemorrhage in 2%. For women, these figures were 85%, 12%, and 3%, respectively. The 28-day case fatality rate was 26.6% (95% CI, 22.9% to 30.2%), with no differences between men and women. Case-fatality increased with age and was higher for intracerebral hemorrhage than for cerebral infarction. CONCLUSIONS: The incidence of stroke in our population-based study ranks low part compared with other European studies. The distribution of stroke types and case fatality rate appear to be similar to those of other industrialized countries.