Cortical silent period in two patients with meningioma and preoperative seizures: a pre- and postsurgical follow-up study.

OBJECTIVES: Prolongation of the cortical silent period (CSP) following transcranial magnetic stimulation has been reported in patients with partial epilepsy involving the primary motor cortex (M1). This study aimed to investigate the relationship between the expected intraindividual variations in risk factors for seizures and CSP duration. METHODS: We studied a 59-year-old woman with a rolandic meningioma and simple motor partial seizures and a 71-year-old woman with a parietal/occipital meningioma and complex partial seizures. Both patients had seizure as their initial symptom with complete postsurgical remission. Repeated pre- and postoperative CSP recordings were made from both first dorsal interosseous muscles. We compared the results to those obtained in 13 normals. RESULTS: In the patient with simple motor partial seizures, the CSP was significantly prolonged in preoperative recordings and 3 weeks after surgery. This CSP lengthening partly subsided 3 months after surgery. Finally, the CSP was normal 6, 8, and 18 months after surgery. In the patient with complex partial seizures, no CSP change was observed. CONCLUSIONS: In our patient with a rolandic meningioma, CSP prolongation was observed when the risk of seizure relapse was supposed to be higher (preoperative and early postoperative periods). This supports the view that CSP changes reflect compensatory mechanisms in M1 epilepsy.

Trials and tribulations in deploying digital imaging network and picture archiving and communication system--film to filmless in 80 days.

The Naval Medical Center Portsmouth (NMCP) was constructed with the intention of deploying a picture archiving and communications system (PACS). All necessary infrastructures were installed and considerable planning was done during construction with the belief that this would make the deployment of the PACS much simpler. This was true during the early deployment; however, as time passed and the system was more heavily used, significant problems arose. User/operator-related and hardware/software-related problems were encountered. Although, most have been corrected, some have persisted and will require considerable manpower and/or fiscal resources to correct. The lesson learned is that no matter how much preparation is done for deploying PACS, many significant problems will surface as the system is used that will require the continued attention of the deployment project officer.

Reorganization of the motor cortex in a patient with congenital hemiparesis and mirror movements.

Abnormal branching of corticospinal fibers from the unaffected motor cortex is responsible for mirror movements in patients with congenital hemiparesis, but it is unknown which mechanisms enable these patients to lateralize motor activity. Using multiunit electromyographic analysis and transcranial magnetic stimulation, the authors provide evidence for nonbranched crossed and uncrossed corticospinal projections and intracortical inhibition of the mirror hand. They propose that this remarkable reorganization of the unaffected motor cortex helps these patients to reduce mirror movements.