Incidence of Parkinson's disease in Norway: the Norwegian ParkWest study.

OBJECTIVE: To present the incidence of Parkinson's disease (PD) in Norway and to explore gender influences on incidence and age at onset, as well as severity and pattern of parkinsonism at the time of diagnosis in a representative drug naïve cohort with newly diagnosed PD. METHODS: In four Norwegian counties comprising a base population of 1 052 075 inhabitants, multiple sources of case ascertainment and a four step diagnostic procedure were used to establish a representative cohort of patients with incident PD at a high level of diagnostic accuracy. Of a total of 604 subjects referred to the study, 265 individuals fulfilled the clinical research criteria of PD at their latest clinical visit, at a mean 28 months after identification. RESULTS: The incidence of PD in the study area, age standardised to the 1991 European standard population, was 12.6/10(5yr-1) (95% CI 11.1 to 14.2). The overall age standardised male to female ratio was 1.58 (95% CI 1.22 to 2.06), with a consistent male preponderance throughout all age groups. Clinical onset of PD was later in women than in men (68.6 vs 66.3 years; p = 0.062) whereas severity and pattern of parkinsonism in drug naïve patients was not different between genders at the time of diagnosis. CONCLUSION: Incidence rates of PD in Norway are similar to those in other Western European and American countries. Female gender was associated with a considerably lower risk of PD and slightly delayed motor onset but had no impact on severity of parkinsonism or clinical phenotype in incident drug naïve PD, suggesting that the female gender influences on the nigrostriatal system are most pronounced in the preclinical phase of the disease.

Cryopreservation of porcine fetal ventral mesencephalic tissue for intrastriatal transplantation in Parkinson's disease.

In this study we examined the efficacy of cryopreserving porcine fetal mesencephalic tissue. After microscopical dissection of the ventral mesencephalon (VM) from E28 pig fetuses, the collection of explants was randomly divided into two equal parts. One part was directly prepared as cell suspension. The other part was stored in hibernation medium for less than 2 days and then cryopreserved as tissue fragments and stored in liquid nitrogen. After 2 weeks up to 1 year, these tissue fragments were thawed and processed as cell suspensions. After cell counting and assessment of viability, these cell suspensions were used to examine survival, morphology, and neurite formation of the dopaminergic neurons in cell culture as well as after intrastriatal implantation in 6-OHDA-lesioned rats. Comparison of cryopreserved with fresh VM cell suspensions showed no significant difference with respect to cell viability and the average number of living cells per VM explant. The morphology of cultured dopaminergic neurons after cryopreservation was identical to that of fresh cells. After intrastriatal implantation, survival and outgrowth of cryopreserved dopaminergic neurons as well as functional effects did not differ from those of fresh cells. In conclusion, the cryopreservation technique we used proves to be a reliably effective method for storing porcine fetal VM tissue.

Progressive neurological deficit in children with spina bifida aperta.

The results of re-operation of 15 patients with spina bifida aperta are reported. The operation was necessary because of neurological deterioration with increasing motor and bladder dysfunction. In all patients a tethered cord syndrome was present (CT-myelography). The myelum was adherent to the scar of the myelomeningocele repair. At operation the myelum is released from the adherent scar and in this way untethered. The early complications were mild except for one patient with decompensation of hydrocephalus. The aim of the operation was to stop further progression. The results of the operation were satisfactory with stabilisation of motor function in four patients and improvement of motor dysfunction in ten patients. Backache or fixation, bladder dysfunction and abnormal foot shape improved in some of the patients. In our experience the operative untethering procedure was useful. Intensive neurological control of operated spina bifida aperta patients is mandatory especially in those patients who can walk.