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Magnetic resonance imaging (MRI) is becoming a very useful diagnostic tool for the ophthalmologist. However, there is still some confusion among ophthalmologists and other clinicians regarding ordering and interpreting imaging studies. The role of MRI in the evaluation of vitreoretinal lesions is reviewed in this article by emphasizing the MR features of retinal tumors and simulating retinal or vitreal lesions. A special description of MR requirements for imaging the intraocular structures is provided as well as a review of the MR features of solid and fluid materials used in retinal surgery.

The management of uveal melanoma has evolved tremendously for the past century, and more recently there is a trend toward more focal conservative treatment. Enucleation is still performed for large uveal melanoma when there is no hope for useful vision with conservative treatment. Plaque radiotherapy is particularly recommended for medium- or small-sized uveal melanoma. Special custom-designed plaque radiotherapy can be used for iris, ciliary body, or juxtapapillary choroidal melanoma. Charged-particle irradiation constitutes an alternative treatment modality for posterior uveal melanoma. However, charged-particle therapy is limited by the availability of appropriate therapeutic facilities. Local tumor resection using lamellar sclerouvectomy is mainly suitable for selected iris, ciliary body, or anterior choroidal tumors with smaller basal dimension and greater thickness. Ablative laser photocoagulation is indicated for very selected cases of small posterior choroidal uveal melanoma. Combined plaque radiotherapy with indirect ophthalmoscope laser therapy appears to be a more effective local tumor treatment plan than plaque radiotherapy alone. Transpupillary thermotherapy is the newest modality used as primary treatment or as complementary method to brachytherapy for treatment of selected choroidal melanomas. Hyperthermia with infrared irradiation below photocoagulation level produces tumor necrosis with few ocular complications. Based on the published ophthalmic literature, it seems that enucleation carries the same survival prognosis as each of the conservative treatment modalities.

There have been many recent advances in the diagnosis and management of children with retinoblastoma. Regarding diagnosis, the judicial use of ancillary studies, particularly B-scan ultrasonography, has been instrumental in supplementing the diagnosis when opaque media preclude a clear view of the underlying neoplasm. Computed tomography and magnetic resonance imaging are important in the early detection of associated pinealoblastoma, which occurs as part of the recently described syndrome of "trilateral retinoblastoma." With regard to management, the technique of enucleation continues to improve and the scleralized hydroxyapatite implant is now available to provide a better cosmetic appearance and better motility of the artificial eye. Methods have been described for harvesting fresh tumor tissue immediately after enucleation for special DNA studies. Recent reports have documented a decreasing frequency of enucleation and an increasing tendency to use eye-preserving methods of management. Plaque radiotherapy, which provides more localized irradiation to the specific tumor, is gradually supplanting external beam irradiation for localized retinoblastoma that does not exhibit extensive vitreous seeding. The indications and contraindications for cryotherapy and photocoagulation have been more clearly delineated. The role of chemotherapy is being evaluated in the treatment of primary retinoblastoma and for metastatic disease. New breakthroughs in genetic research are being applied to clinical genetic counseling. The prognosis for life and for preservation of vision has improved greatly in recent years.