Ruthenium-106 plaque brachytherapy for symptomatic vasoproliferative tumours of the retina.

AIM: To investigate the safety and efficacy of beta ray brachytherapy in treatment of vasoproliferative tumours of the retina (VTR). METHODS: 35 consecutive patients with symptomatic VTR were treated with a ruthenium-106 ((106)Ru) plaque. Three tumours had been treated previously (two with cryotherapy; one with transpupillary thermotherapy). 32 VTR (91.4%) were located in the lower half of the retina and all of them were found between the mid-periphery and the ora serrata. The mean tumour thickness was 2.8 mm. An exudative retinal detachment was present in 25 eyes (71.4%) and in 15 cases (42.9%) hard exudates were found in the macula. The major symptom was loss of vision (77.1%). RESULTS: Brachytherapy was well tolerated by every patient. The mean applied dose was 416 Gy at the sclera and 108 Gy at the tumour apex. In all but four eyes (88.6%), it was possible to control the VTR activity. The median follow up time was 24 months. Three of the above mentioned four eyes with treatment failure had had secondary glaucoma before therapy. There was no case of radiation induced neuropathy or retinopathy. Cataract surgery was necessary for five patients. The development of epiretinal gliosis was the most common event during follow up (n = 10, 28.6%). The mean visual acuity decreased slightly (0.33 before and 0.29 after brachytherapy). Multivariate analysis showed that the presence of macular pathology before treatment was associated with a 6.1-fold risk of vision of 0.25 or better (p = 0.03). CONCLUSIONS: beta ray brachytherapy with (1106)Ru plaques was able to control the activity of VTR and retain vision. Cases with secondary glaucoma before treatment had a very poor prognosis.

Whole-body fluorine-18 fluordeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in staging of advanced uveal melanoma.

Fluorine-18 fluordeoxyglucose positron emission tomography (FDG-PET) is an useful tool in diagnosing and monitoring of malignant cutaneous melanoma. However, the feasibility and usefulness of FDG-PET in uveal melanoma is not yet established. We present a patient with suspected advanced uveal melanoma who underwent combined FDG-PET/computed tomography (CT) for staging. FDG-PET/CT images demonstrated vital intraocular tumor. Anatomical assignment of the malignancy to the choroid was possible by means of the coregistered computed tomography. Furthermore, PET revealed an unknown otherwise undetected vital liver metastasis. We conclude that combined FDG-PET/CT has potential to further improve staging and therapy planning in patients with advanced uveal melanoma.

High resolution magnetic resonance imaging of retinoblastoma.

BACKGROUND/AIMS: Diagnosis of retinoblastoma is mainly based on indirect ophthalmoscopy, but additional imaging techniques are indispensable for the staging of the disease. A new high resolution magnetic resonance imaging (MRI) technique for the examination of the eye was evaluated. A new surface coil with a diameter of 5 cm allows a field of view of 60 mm with an in-plane resolution of 0.8 mm. We compared preoperative MRI scans with the histology after enucleation in 21 cases of retinoblastoma. Parameters studied were appearance of retinoblastoma, choroidal and scleral infiltration, extraocular extension, optic nerve infiltration, and vitreous seeding. RESULTS: All retinoblastomas could be visualised as hypointense to vitreous on T2 weighted images and slightly hyperintense to vitreous on plain T1 weighted images with a moderate enhancement after contrast application. Histology revealed seven cases with infiltration of the optic disc or optic nerve. Preoperative MRI scans depict juxtapapillary tumour masses, but it was impossible to differentiate between a juxtapapillary retinoblastoma, a prelaminar infiltration of the optic disc, or a just postlaminar optic nerve infiltration. In five of 14 cases with a proved tumour infiltration of the choroid, MRI scans showed an inhomogeneous contrast enhancement of the choroid in enhanced T1 weighted sequences beneath the retinoblastoma. Whether this sign is specific for a choroidal infiltration or is just an artefact remains unclear. High resolution MRI scans did not allow the exclusion of this form of intraocular tumour extension. All nine cases with proved vitreous seeding were not detected by MRI scans. None of these cases showed scleral infiltration or orbital tumour extension. Therefore, it is not possible to judge the rank of this technique in detecting orbital tumour growth. CONCLUSION: The new MRI technique is of limited value in visualisation of prelaminar or postlaminar infiltration of the optic nerve. Advanced choroidal infiltration might be visualised by contrast enhanced T1 weighted MRI scans, but the available spatial resolution did not allow the exclusion this critical form of tumour growth by MRI scans. Nevertheless, high resolution MRI with the new surface coil has superior contrast and spatial resolution compared to computed tomograph (CT) or other available imaging techniques. MRI cannot replace CT in detecting tumour calcification but with increasing experience with this new technique it should be possible to renounce CT scans in the majority of cases of retinoblastoma.

Thermochemotherapy in hereditary retinoblastoma.

BACKGROUND/AIM: The combination of chemotherapy and transpupillary thermotherapy, thermochemotherapy (TCT) has become an established part of the treatment plan in advanced retinoblastoma. The aim of this study was to identify safe indications, the complications as well as the limitations of this new treatment for retinoblastoma. METHODS: Tumour response and side effects of TCT with an indirect laser ophthalmoscope (spot size about 400 micro m) in 55 tumours of 26 children with bilateral retinoblastoma were analysed. Using the Reese-Ellsworth classification system, nine of 35 eyes were classified as type I, 13 eyes as type II, 10 eyes as type III, and three eyes as type V. The mean age of the children was 0.74 (SD 0.61) years. The mean tumour height was 3.5 (2.3) mm with a mean diameter of 6.1 (4.1) mm. Treatment parameters were 4.3 (1.6) (median 5) thermochemotherapy sessions with a mean energy of 539 (211) mW and a mean duration of 13.5 (5.6) minutes. Chemotherapy courses (vincristine, etoposide, and carboplatin) were repeated every 3 weeks. The mean follow up period was 1.25 (0.6) years. RESULTS: Local recurrence occurred in 21 tumours (38%), with a mean onset of 3.2 (2.9) months after TCT. The risk of tumour recurrence was correlated with tumour height. The recurrence rate was 17% for tumours with a height less than 2 mm, 37% for tumours with a height between 2 and 4 mm, and 63% for larger retinoblastomas. Multivariate analysis identified fish flesh regression after TCT (p = 0.0007) as the most important risk factor for tumour recurrence besides tumour height (p = 0.001) and the necessity of increased laser power during TCT sessions (p = 0.018). Complications during therapy included transient corneal opacification in two eyes (6%), focal iris atrophy (three eyes, 8.5%), peripheral lens opacity (two eyes, 6%), circumscribed transient retinal detachment (one eye, 3%) and diffuse choroidal atrophy (one eye, 3%). CONCLUSION: TCT using an indirect laser ophthalmoscope with a spot size of about 400 micro m was efficient for retinoblastoma with a tumour height less than 4 mm. In larger tumours, the recurrence rate was unacceptably high. Fish flesh regression after TCT correlates with a higher rate of local tumour recurrence. Treatment related complications occurred in less than 9% of the treated eyes.

Phacoemulsification following treatment of choroidal melanoma.

BACKGROUND: Little is known about the risks, effects and results of phacoemulsification following treatment with different modalities of choroidal melanoma. METHODS: In a retrospective study, records were evaluated of 72 patients who underwent cataract surgery after treatment of choroidal melanoma (35 were treated with iodine-125 plaques, 27 with ruthenium-106 plaques, eight by tumor excision, and two with proton beam irradiation). The data were analyzed with respect to complications, effects on postoperative tumor care and visual outcome. RESULTS: Phacoemulsification was performed at a mean interval of 21.5 months after primary tumor therapy. An intraocular lens (IOL) was implanted in 93% of the cases. The mean postoperative follow-up time was 16.2 months. Preoperative problems were rubeosis iridis (30.5%), secondary glaucoma (34.7%) and posterior synechiae (41.6%). Intraoperatively, defects of the posterior capsule occurred in 12.5%. Visual acuity equal to or better than preoperative vision was found in 95.8% of the patients as the best postoperative measurement and in 72.2% at the last follow-up measurement. A deterioration of more than two lines in visual acuity was observed in 4.2% as the best postoperative vision and in 27.8% at the last documented examination. Phacoemulsification was not the cause of deterioration in any of the cases. After cataract surgery, tumor retreatment was necessary in 19.4%. Treatment of radiation retinopathy was performed for the first time in 13.8%. Metastases developed in six patients (8.3%). CONCLUSION: Phacoemulsification following treatment for choroidal melanoma is both possible and advisable. The majority of patients have enhanced visual acuity. No decrease of vision occurred as a result of cataract extraction. The postoperative care of intraocular tumors and the treatment of radiation retinopathy is improved by timely cataract surgery.