[Endoresection of large uveal melanomas after pretreatment by single-dose stereotactic convergence irradiation with the leksell gamma knife--first experience on 46 cases]. / Endoresektion grosser Melanome der Uvea nach stereotaktischer Single-dose-Vorbestrahlung mit dem Leksell Gamma-Knife -- Erste Erfahrungen an 46 Fällen.

BACKGROUND: The aim of this non-comparative, consecutive case series is to evaluate the short-term results after endoresection of large uveal melanomas in combination with pretreatment with stereotactic gamma knife radiosurgery. METHODS: Between March 2000 and November 2002, forty-six patients with large uveal melanomas underwent stereotactic radiosurgery followed by endoresection of the tumour via a standard three-port vitrectomy including laser photocoagulation and silicone oil tamponade. The average tumour height was 9.5 mm. The minimum dose delivered to the tumour volume was 25 Gy. RESULTS: The median follow-up time was 410 days. In 40 cases (87 %), the eye was retained with a VA of 20/200 or better in 30 cases (65.2 %) and 20/63 or better in ten cases (21.7 %). In 12 eyes with a follow-up of >/= 0.5 years, the median VA was 20/80 after silicone oil removal and cataract surgery had been performed. Six eyes (13 %) were enucleated due to serious complications caused by the radiosurgery (3 cases) or endoresection (3 cases). In 13 patients (28.2 %), additional major surgery was required. Seven patients developed liver metastases during follow-up and six patients died. No local tumour recurrences were observed. CONCLUSIONS: Eyes with large uveal melanomas can be salvaged by stereotactic radiotherapy followed by endoresection.

[Stereotactic radiosurgery using the Gamma Knife for large uveal melanomas]. / Stereotaktische Konvergenzbestrahlung grosser uvealer Melanome mit dem Gamma-Knife. Vorläufige Ergebnisse bei 100 Patienten.

BACKGROUND: We report the results over 3 years with stereotactic radiosurgery using the Gamma Knife for large and unsuitably located uveal melanomas. PATIENTS AND METHODS: A total of 100 patients (51 male, 49 female) have been treated since 1997 following a standardised treatment protocol (outpatient single-shot treatment, maximum dose 50 Gy, tumour margin dose min.25 Gy, retrobulbar anaesthesia alone for globe fixation). The localisation and/or dimension of the tumours did not allow radiation brachytherapy with Ru106 plaques. Of the tumours 18 were located in the ciliary body, 61 were located at the posterior pole, and 21 were located in the mid-periphery. All patients were followed and tested ophthalmologically and neuroradiologically at regular intervals. The 1-year follow-up data were available for 73 patients, 2-year follow-up data for 33 patients and 3-year follow-up-data for 17 patients. RESULTS: Before therapy the maximum apical tumour height (MAH) was median 7.8 mm (95% CI 2.9-12.5 mm): 1 year after treatment (73 patients) the MAH was median 5.7 mm (95% KI 2.4-10.2 mm),2 years after treatment (33 patients) the MAH was median 4.3 mm (95% KI 2.2-8.8 mm),and 3 years after treatment (17 patients) the MAH was median 4.6 mm (95% KI 2.4-8.5 mm). All differences to the MAH of the corresponding patients before treatment were statistically significant (paired t-test). Within the first year after treatment seven patients were enucleated due to a painful secondary glaucoma,within the second year after radiation two patients (one tumour recurrence, and one secondary glaucoma) and within the third year one more patient (tumour recurrence) was enucleated. CONCLUSIONS: Our 3-year results demonstrate that radiosurgery using the Gamma Knife is beneficial in achieving a local tumour control in 98% of eyes with large and unsuitably located uveal melanomas. The risk for a secondary enucleation is highest in the first year after treatment with a favourable overall rate of 10%. Due to the excellent local tumour control rate we decreased the maximum dose to 40 Gy (min.tumour margin dose 20 Gy) in the subsequently treated patients.

[Endoscopic resection of malignant melanomas of the uvea after preoperative stereotactic single dose convergence irradiation with the Leksell gamma knife]. / Endoresektion maligner Melanome der Uvea nach präoperativer stereotaktischer Einzeldosis-Konvergenzbestrahlung mit dem Leksell-Gamma-knife.

In cases of large volume and highly prominent melanomas of the uvea, it is rare for conventional methods of radiation therapy to enable salvage of the globe or even residual functionality of the affected eye. Complications due to the massive amount of accumulated necrotic tissue often necessitate subsequent enucleation of the blinded eye. Tumor-destroying, single-dose convergence irradiation (radiosurgery) of such tumors applied shortly before endoresection can represent a possible therapeutic alternative in these types of cases.

[Stereotaxic precision irradiation of large uveal melanomas with the gamma knife]. / Die stereotaktische Präzisionsbestrahlung grosser uvealer Melanome mit dem Gamma-Knife.

BACKGROUND: We report our experience with stereotactic radiosurgery using the Gamma-knife in large uveal melanoma unsuitable for brachytherapy (Ru106). PATIENTS AND METHODS: We treated 35 patients (16 male, 19 female; age: median 59 years (95% Confidence interval (CI): 31-84 years; 18 right eyes, 17 left eyes). 7 tumors were located juxtapapillary, 16 tumors were located in the mid-periphery and 12 tumors were located in the ciliary body, The localization and/or the dimension of the tumors did not allow for radiation brachytherapy (Ru106). All patients underwent regular clinical, echographical and neuroradiological follow-up examinations. RESULTS: The follow-up time was median 12 months (95% CI: 4-20 months). A local tumor control defined as either continuous tumor regression or stopping of tumor progression was achieved in 34 (97%) of the 35 treated patients within the observation period. The eye of one patient was enucleated due to tumor regrowth. Maximum apical tumor height according to standardized A-scan before treatment was median 9.1 mm (95% CI: 3.2-13.9 mm) and after treatment median 6.4 mm (95% CI: 2.1 bis 11.9 mm). The difference was statistically highly significant (p < 0.001, one-tailed paired t-test). CONCLUSIONS: Our results in 35 patients indicate that radiosurgery using the Gamma-knife is beneficial in retaining the eyes of patients with large uveal melanomas that are not suitable for brachytherapy (Ru106).

Stereotactic radiosurgery of large uveal melanomas with the gamma-knife.

OBJECTIVE: To present our experience with the Gamma-knife in treating large uveal melanomas with stereotactic radiosurgery. DESIGN: Prospective, noncomparative, interventional case series. PARTICIPANTS: Fifty-eight patients with unilateral uveal melanomas were treated from 1996 through 1999 with stereotactic radiosurgery using the Gamma-knife. From these we report the results of 35 patients who had a follow-up of more than 1 year after irradiation. INTERVENTION: Stereotactic radiosurgery with the Gamma-knife. MAIN OUTCOME MEASURES: Tumor control, maximum apical tumor height, eye retention rate, and visual acuity. RESULTS: In 34 eyes (97%), local tumor control was achieved. The maximum apical tumor height decreased from a median of 9.1 mm (95% confidence interval [CI], 3.2-13.9 mm) before treatment to 6.2 mm (95% CI, 2.1-11.9 mm) at 1 year after treatment (P<0.001, paired t test). The tumor volume decreased from a median of 0.8 cm(3) before treatment to 0.5 cm(3) 1 year after treatment (P<0.001, paired t test). Two eyes required enucleation (one radiation failure, one secondary glaucoma). The median visual acuity decreased from 20/60 (95% CI, hand movement [HM] to 20/20) before treatment to 20/200 (95% CI, HM to 20/30) at 1 year after treatment (P = 0.001, paired t test). CONCLUSIONS: Stereotactic radiosurgery using the Gamma-knife is an alternative to enucleation in treating large uveal melanomas. The visual function may be preserved in selected cases.

Microstereometrically guided cortical stimulation for the intraoperative identification of the central motor strip.

A rangable stimulation tool based on the sonar microstereometric system has been developed for the intraoperative identification of the central motor strip. The elicited motor evoked potentials (MEPs) were recorded with surface electrodes and displayed together with the corresponding stereometric coordinates of the stimulation site. MEP data were overlaid in 'real time' on preoperatively scanned CT images on a computer screen. The system has been used during open microsurgical procedures in 6 patients with small tumors near the central motor strip or related 'eloquent' areas. Three operations have been performed under local anesthesia, 3 under general anesthesia. It was possible to operate on tumors located closely to functionalal relevant areas of the brain not only stereotactically, but also with function guidance.