Patients treated by Model-C gamma knife with APS are less exposed to non-therapeutic irradiation.

OBJECTIVE: The aim of this study was to compare the defocused (non-therapeutic) irradiation between the Model-C gamma knife with the automatic positioning system (APS) and with the non-APS mode. METHODS: 41 males and 59 females (mean age: 54 years) had the following pathologies: 38 benign tumors, 43 malignant tumors, 16 vascular lesions, and 3 trigeminal neuralgias. These included 192 lesions (mean volume: 4.8 mL), 61 (32%) of them were located deeply. The radiation treatment time needed and the choice of helmets and shots for each lesion were analyzed. The inter-group difference is analyzed using the one-way ANOVA method. RESULTS: The APS mode could be applied alone in 79 patients or was always possible in nearly 95% of patients with benign lesions. APS-treatment failed in three patients due to unexpected collisions, and the other 18 harbored some advanced peripheral metastatic lesions. The non-APS mode required 47% more defocused time than the pure APS mode (1.1 vs. 0.75 minutes, p<0.01) before starting the next shot. Patients treated by the APS mode are exposed to a 70% less (p<0.05) unplanned, defocused irradiation dose than those by the non-APS mode. Although there is a tendency in the APS group to use fewer helmets but more shots per lesion for achieving an optimal dosimetry, there was no difference in the averaged defocused time per patient. CONCLUSIONS: The APS system makes GK radiosurgery run more smoothly, rapidly, comfortable and safer than ever. It improves the design of more conformal dose plans, especially for benign lesions, and the patients will also be exposed to less unnecessary radiation doses.

Intermediate-term results of endoscopic transaxillary T2 sympathectomy for primary palmar hyperhidrosis.

BACKGROUND: This report examines the intermediate-term results of endoscopic transaxillary T2 sympathectomy for palmar hyperhidrosis. METHODS: A retrospective review was carried out of 91 consecutive patients, 38 men and 53 women, with a mean age of 23 years. Attention was focused on patient satisfaction, late complications and morbidity. RESULTS: After operation, no patient died or developed Horner's syndrome. Nine of 21 patients with craniofacial, five of 16 with axillary and 17 of 73 with plantar hyperhidrosis showed simultaneous improvement. Fifteen patients (16 per cent) developed recurrent sweating, but none required reoperation. The overall mean satisfaction rate was 78 per cent with a median 80 per cent improvement using a visual linear analogue scale from 0 (poor) to 100 per cent (excellent). Twelve patients (13 per cent) were dissatisfied with the operative results, mainly owing to compensatory hyperhidrosis, which occurred in 88 patients (97 per cent) within the first year. CONCLUSION: The results of endoscopic sympathectomy deteriorate progressively from the immediate outcome.

Remotely controllable temporary afterloading brachytherapy for malignant brain tumors.

We present the results of six patients with recurrent malignant brain tumors who underwent an alternative system of interstitial brachytherapy. In each patient, the neurosurgeon initially inserted several small catheters into the tumor target through a stereotactic procedure or open craniotomy. Later, the patient was treated using an intracatheter temporary implant of a high-dose-rate 192Iridium. We delivered a mean dose of 6 Gy per fraction into the rim of the tumor margin and limited it to 2 Gy at a distance of 1 cm outwards. Each patient received one fraction, 3 to 5 minutes every 2 days, for a total of three fractions. In between these treatments, patients performed regular daily activities and had nursing care as usual. There was no surgical mortality in this study. One patient had late-onset anemia. This treatment modality has the advantage of combining cytodiagnosis/reduction and radiation within one very short therapeutic time period.

Orientation landmarks of endoscopic transaxillary T-2 sympathectomy for palmar hyperhidrosis.

The identification of the T-2 ganglion through a narrow operative viewfield is the greatest challenge in performing endoscopic transaxillary T-2 sympathectomy, especially for a surgeon who is unfamiliar with the technique. The authors describe a simple anatomical method for identifying the T-2 ganglion during the operation, based on a study of 17 adult cadavers. First, a similar clinical procedure was performed along the anterior or middle axillary line via the second to fourth intercostal spaces to measure the aiming angles and intrathoracic depth needed. Second, the regional anatomical structures and their relationship to bilateral T-2 ganglia were delineated. It was discovered that the superior intercostal artery, a branch of the subclavian artery, was an accessible landmark. This small vessel existed in 87.5% of the cadavers studied. It consistently runs lateral to the parallel sympathetic chain at an average distance of 10 mm. Most important is that it can be easily distinguished where it runs across the inner part of the second rib. The authors emphasize that the superior intercostal artery should be a very beneficial landmark for surgical orientation.