Reinnervation of the urinary bladder after transsection of cauda equina fibres and their microsurgical reconstruction was studied. In five pigs a partial reconstruction with end-to-end suture of the transsected roots was performed inside the dura mater spinalis; four of these, which had a denervated bladder after the transsection, reestablished the micturition reflex 6 months after the reconstructive operation. The results demonstrate that the reestablished micturition reflex was due to a functional regeneration of transsected and sutured motor fibres. Although a regeneration was proved in sensory as well as in motor neurons by morphologic methods, it is doubtful whether the regenerated sensory fibres took part in the reestablishment of the micturition reflex after contact with the spinal cord.

The regeneration of nerve fibres in pigs was studied three months after transection and end-to-end suture of the dorsal and ventral spinal nerve roots L5 and S1. Although no detailed quantitative analysis was performed, it was clearly evident that regeneration in motor roots is significantly more efficacious than in sensory roots. Probably as a reaction to Wallerian degeneration, an increase of histiocytes, fibroblasts and collagen fibrils, as well as a thickening of the sheaths was observed in the transected and sutured roots. Heterotopic glial bundles were found in the regenerated dorsal roots.

Glial bundles growing out of the spinal cord were observed in spinal nerve roots in the pig after their section and surgical repair. The heterotopic occurrence of glial cells, most of which were identified as astrocytes, was more frequent and more pronounced in dorsal than in ventral roots. Several of the glial bundles contained regenerated myelinated axons. These were probably myelinated by cells which showed the typical cytological criteria for oligodendrocytes and the mode of myelination was clearly of central type. It was concluded that the glial outgrowth is induced by degeneration and regeneration of axons passing the central-peripheral transition zone.

Ventral nerve roots of the lumbar area in seven pigs were transected intradurally and resutured microsurgically immediately after transection. Four to seven months after repair electromyography was done via intradural electric stimulation of the resutured roots. Reinnervation was found. Patterns were compared with data from intact animals.

A metastasis from an adenocarcinoma of the lung into a meningotheliomatous and angiomatous meningioma of the falx is described. The meningioma was extirpated six months after pneumonectomy. Literature review of all such rare occurrences is presented in the discussion.