Multiple sclerosis in Malta in 1999: an update.

OBJECTIVES: To ascertain the prevalence of multiple sclerosis (MS) in the islands of Malta and compare it with a previous study undertaken 21 years earlier, when a remarkably low prevalence was found. METHOD: Deaths with MS on the death certificate since the last study were reviewed. Sources of information about new patients were the Hospital Activity Analysis scheme, the MS Society of Malta, the records of the state hospitals, long stay private hospitals and nursing homes, lists provided by the state pharmacies, and magnetic resonance imaging, cerebrospinal fluid, and evoked response studies. Prevalence day was 1 January 1999. The Poser classification was used. RESULTS: Since 1978, 17 patients had died with a verified diagnosis of MS on the death certificate. They included all 10 deaths with MS from the original study and two immigrants. Fifty patients had clinically definite MS (CDMS) and 13 clinically probable MS (CPMS). The prevalence of CDMS was 13.2/100 000 (male 11.2, female 15.2). The prevalence of CDMS and CPMS combined was 16.7/100,000 (male 13.3, female 19.9). The annual incidence was 0.7/100,000. Twelve patients were found with CDMS among the 7213 immigrants resident in Malta (166/100,000). The expected rate was 1/100,000, determined at Maltese born rates. There were major changes in the population distribution during the 21 years between the two studies, with a big increase in the age groups with a high risk of MS. There is a longer expectation of life and the diagnosis in now made earlier. CONCLUSION: Malta still has a low MS prevalence. In comparison with Sicily and other Mediterranean countries of Europe it offers an opportunity to ascertain the genetic and environmental factors responsible for the disease.

Hypoperfusion-related cerebral ischemia and cardiac left ventricular systolic dysfunction.

BACKGROUND: Cardiomyopathy and low ejection fraction (EF) are associated with cardiac thrombi and cardiogenic embolism but may also be risk factors for hypoperfusion-related cerebral ischemia (HRCI). Current stroke subtype criteria do not include an HRCI category. METHOD: To look for evidence of HRCI, we compared mean infarct volume between serial patients with EF < or =35% and high-grade (> or = 70%) carotid stenosis and serial patients with normal EF and high-grade carotid stenosis. We matched serial stroke patients with EF < or =35% with stroke patients with normal EF and compared the number and type of ischemic lesion (symptomatic or asymptomatic) and mean infarct volume on magnetic resonance imaging. We blindly compared stroke subtype in these groups using modified Trial of ORG 10172 in Acute Stroke Treatment (TOAST) criteria, including an HRCI category. RESULTS: In patients with carotid stenosis, ipsilateral infarct volume was greater with EF < or = 35% (74.7 mL, 95% CI, 17.3-132.1 mL) than in controls (17.1 mL, 95% Cl, 9.4-24.8 mL) (P<.05). There was no difference in the mean number of HRCI-compatible infarcts on computed tomography scan between patients with low EF and controls. Symptomatic HRCI occurred in 4 of 15 patients with low EF and in 0 of 15 controls. CONCLUSIONS: Symptomatic HRCI occurs in patients with low EF. Severe arterial stenosis may interact with left ventricular systolic dysfunction to cause cerebral hypoperfusion. Modification of the TOAST criteria to include an HRCI subtype is feasible and HRCI should be included as a stroke subtype.

Spinal cord MRI hyperintensities in cervical spondylosis: an ischemic pathogenesis?

The pathophysiology of focal spinal cord MRI T2 hyperintensity (SCHI) in patients with cervical spondylosis is uncertain. This study was undertaken to determine the frequency and cause of SCHI. The authors reviewed serial cervical spine magnetic resonance imaging (MRI) reports and reviewed scans with spondylosis and cord compression or SCHI. The authors noted the location, shape, and extent of SCHI, and severity of spondylosis (expressed as a spondylosis score [SS]). The authors recorded the age and vascular risk factors for each patient. Nineteen of 273 scans (7%) with cervical spondylosis and 19 of 36 scans (53%) with cord compression had SCHI. The SCHI extended for one vertebral level from the compression in 12 patients and for three vertebral levels in 5 patients, and were distant from the compression in 2 patients. The SCHI had a focal, symmetrical, anterior spinal artery terminal zone location in 16 of 19 scans (84%). A rim isointense with normal cord separated all SCHI from the pial surface. Patients with SCHI were older (58.3 years +/- 12.8 years versus 46.8 +/- 8.1 years) (p = 0.007) and had a higher SS (5.7 +/- 2.4 versus 3.9 +/- 1.4) (p = 0.02) than patients without SCHI. The SCHI relates to the severity of cervical spondylosis. The anterior spinal artery territory location, the normal cord between SCHI and the compressive lesion, and the presence of SCHI at a distance from the compressive level all suggest an ischemic basis for SCHI.