Spontaneous twiddler's syndrome in a patient with a deep brain stimulator.

BACKGROUND: The subcutaneous placement of IPGs with electrodes to various intracranial and extracranial sites for the purpose of controlling conditions such as essential tremor, epilepsy, Parkinson's disease, and pain is increasing. Experience with similar placement of cardiac pacemakers and defibrillators had revealed the possibility of generator migration and subsequent lead fracture either spontaneously or, more often, through a patient's conscious or subconscious manipulation of the device through the skin. This phenomenon has been termed twiddler's syndrome. CASE DESCRIPTION: An elderly patient's IPG used in the treatment of a debilitating essential tremor had spontaneously rotated during the course of normal physical activities. This resulted in the twisting and fracturing of the leads. Torsional displacement of and tissue stress on subauricular lead connectors caused early discomfort in that region. Recurrent tremors occurred upon device failure. Surgical replacement of the IPG lead and use of a polyester pouch sutured to the surrounding fascia were observed to correct the problem. CONCLUSION: Those caring for patients, especially elderly and obese patients, with an IPG should be aware of the potential of device failure as a result of spontaneous twiddler's syndrome.

The Brain Tumor Cooperative Group NIH Trial 87-01: a randomized comparison of surgery, external radiotherapy, and carmustine versus surgery, interstitial radiotherapy boost, external radiation therapy, and carmustine.

OBJECTIVE: The objective of the Brain Tumor Cooperative Group NIH Trial 87-01 trial was to investigate the effect of additional implanted radiation therapy in newly diagnosed patients with pathologically confirmed malignant gliomas. METHODS: The study involved a randomized comparison of surgery, external beam radiotherapy, and carmustine (BCNU) versus surgery, external beam therapy, interstitial radiotherapy boost, and BCNU in newly diagnosed malignant gliomas. (125)I was chosen as best suited for this effort because it allowed preimplantation planning and postimplantation quality assurance review. Two hundred ninety-nine patients met the eligibility criteria and were randomized into the two arms of the study between December 1987 and April 1994. Follow-up continued for an additional 3 years. Twenty-nine patients were identified as having committed protocol violations and were excluded, resulting in 270 subjects in the Valid Study Group. One hundred thirty-seven patients received external beam radiation and BCNU, and 133 underwent the (125)I implantation plus external beam radiation and BCNU therapy. RESULTS: The overall median survival for the Valid Study Group was 64.3 weeks. The median survival for patients receiving additional therapy of (125)I was 68.1 weeks, and median survival for those receiving only external beam radiation and BCNU was 58.8 weeks. The cumulative proportion surviving between the two treatment groups was not statistically significantly different (log-rank test, P = 0.101). As in other studies in the literature, age, Karnofsky score, and pathology were predictors of mortality. Additional analyses incorporating an adjustment for these prognostic variables, either in a stratified analysis or Cox proportional hazards model, did not result in statistically significant differences in the cumulative proportion of patients surviving between the two treatment groups. CONCLUSION: We conclude that there is no long-term survival advantage of increased radiation dose with (125)I seeds in newly diagnosed glioma patients.