Predictive factors for the development of rubeosis following proton beam radiotherapy for uveal melanoma.

AIMS/BACKGROUND: Proton beam radiotherapy can effectively treat primary uveal melanomas of any size. Some patients, however, develop adverse late effects following treatment and the purpose of this study was to determine which factors give rise to a poor local outcome. METHODS: The hospital records from a first cohort of 127 patients treated by protons from 1989 to 1992 were reviewed retrospectively. The presence of rubeosis was selected as a measure of significant ocular damage. Split file analysis was performed with 73 cases forming a test group with the remaining 54 cases acting as a validation group. RESULTS: Large tumour size and the presence of retinal detachment were significant, independent risk factors for developing rubeosis for both the test and validation groups. These factors also predicted subsequent enucleation for uncontrolled ocular pain. Patients with tumours too large to plaque and with an associated retinal detachment had a 90% chance of developing rubeosis within 4 years of proton beam radiotherapy. CONCLUSIONS: Patients with a uveal melanoma too large for plaque therapy and an associated retinal detachment run a very high risk of developing rubeosis after proton beam radiotherapy and one third of individuals developing rubeosis required enucleation for pain even if local tumour control was satisfactory.

A comparison of slit-lamp supported versus hand-held biometry.

Biometry allows determination of the final refractive outcome following cataract extraction with intraocular lens implantation. We compared the accuracy of axial length measurement performed with the slit-lamp supported biometry probe versus a hand-held technique. The two methods of biometry were performed on 32 patients undergoing endocapsular cataract extraction with lens implantation. One of the methods was selected at random in order to predict implant power for a desired refractive outcome using the SRK-T formula. There was no difference in 'within-subject' variance of axial length measurement between the two methods (t = 1.74, p = 0.091), and there was no difference in refractive outcome when the power calculations for the two techniques were compared (t = 0.12, p = 0.906). The hand-held technique provides a useful alternative method of biometry in 'difficult' patients.

Midline nasal dermoids presenting like discharging lacrimal sac mucocoeles.

Two cases of midline intranasal dermoid cysts presenting like discharging lacrimal sac mucocoeles in children are described. The diagnosis of this rare condition is suggested by the presence of midline nasal cutaneous dimples, although these may be associated with isolated anomalies such as nasal dermoid cyst, encephalocoele or glioma.