Exoresection and endoresection for uveal melanoma

Abstract

Surgical resection of uveal melanomas is an alternative eye-salvaging approach to the more commonly used irradiation techniques. There are two surgical resection techniques: Transscleral resection or "Exoresection" via a partial lamellar sclerouvectomy and "Endoresection" via a pars plana vitrectomy. While exoresection is more applicable to anteriorly located tumors with ciliary body and/or iris involvement, endoresection is more suitable for posteriorly located tumor without ciliary body involvement. Both approaches are suitable for large tumors with >8 mm in thickness. In general, eyes containing these large tumors have a very dismal prognosis regarding long-term visual function, eye retention, and irradiation-induced side effects. By removing the tumor burden from the eye, histopathologic and cytogenetic information of the tumor is available and complications associated with the so-called toxic tumor syndrome are avoided. However, both types of surgical resection are challenging surgical procedures, bearing the risk of early and late postoperative complications.

Keywords: Endoresection; Exoresection; Melanoma; Nevus; Partial Lamellar Sclerouvectomy.

Figure 1

(a) Inferiorly located iridociliary melanoma. (b) After exoresection via PLSU and complete tumor removal, notching of the lens induced by the tumor and posterior subcapsular cataract are seen. (c) After phacoemulsification and intraocular lens placement, the patient achieved 20/30 vision in this eye (Reproduced from Kurt and Gündüz11)

Figure 2

(a) Massive iridociliochoroidal melanoma producing corneal touch. (b) Gross photograph of the excised tumor showing a greater than 10-mm diameter uveal melanoma. (c) Anterior segment view 1 month after PLSU showing the absence of the iris from 7 to 11 o’clock after pupillary dilation. The corneal pigment was left untreated. (Reproduced from Kurt and Gündüz11)

Figure 3

Fundus photograph showing mild vitreous hemorrhage one day after surgery in an eye that underwent PLSU

Figure 4

Scleral thinning in the superonasal quadrant of an eye that underwent PLSU for an iridociliary melanoma (Reproduced from Kurt and Gündüz11)

Figure 5

(a) Large choroidal melanoma obscuring funduscopic view to the posterior pole. Visual acuity is 20/100. (b) B-scan ultrasound of the tumor depicted in Figure 4(a) showing a 11.9-mm-thick mushroom-shaped choroidal melanoma. (c) Early postoperative view of the fundus of the eye depicted in (a) 2 days after endoresection. Visual acuity is 20/200. (d) Late postoperative view of the fundus of the eye depicted in (a) 18 months after endoresection. Visual acuity is 20/25.