Partial lamellar sclerouvectomy (PLSU) is a surgical procedure used in the treatment of uveal tumors or uveal malignant melanoma, where the ciliary body and choroid are involved. Other lesions that can be treated include iridociliary nevus, iris nevus, and iridociliary melanocytoma. It involves dissecting a partial thickness scleral flap and removing the intraocular tumor.
PLSU is recommended for less thick tumors that are also smaller in diameter. Often, they are benign ciliary body lesions with iris extensions. PLSU is designed to excise the tumor while leaving the sensory retina and outer sclera intact. It is more challenging to access the surgical site to remove a ciliary body lesion involving the choroid, when it is relatively larger. Therefore, a lamellar scleral flap is created for easier access.
PLSU can treat both malignant tumors or melanoma and benign lesions. The different benign types that can be treated by PLSU include:
- Adenoma of the pigment epithelium of the ciliary body
- Adenoma of the non pigmented epithelium of the ciliary body
Also Known As
- Block Excision
- Eye Wall Resection
- Partial choroidectomy
- Transscleral Local Resection
Before the Procedure
The patient will undergo extensive medical and ocular evaluation. The surgeon explains the treatment options in detail, and the patient has the liberty to choose among PLSU, enucleation, and radiotherapy.
Histopathological tests are undertaken to study the manifestations of the ciliary body tumor microscopically. A fine-needle aspiration biopsy is also conducted to diagnose the condition. PLSU is usually performed in ciliary body tumors that measure less than 15 mm in largest diameter but not exceeding 7 mm posterior to the equator.
The patient will receive hypotensive anesthesia to maintain low systemic blood pressure. The systolic blood pressure should be kept at between 50-70 mm Hg. The surgeon will:
- Perform a conjunctival peritomy and localize the tumor using transillumination (which determines the location of the tumor) and indirect ophthalmoscopy
- Prepare a lamellar scleral flap
- Use pars plana vitrectomy to decompress the globe if the tumor is large
- Make an incision through the inner scleral fibers around the tumor
- Remove the tumor together with normal uveal tissues and the dissected inner scleral fibers
- Suture back the scleral flap to its original location
- Perform vitreoretinal surgery and use silicone oil tamponade if a retinal tear occurs. This is performed alongside a lensectomy if the lens is damaged or if there is a cataract
With the modern-day availability of plaque radiotherapy, the surgeon may use adjunctive brachytherapy following PLSU in melanoma cases.
Risks & Complications
Complications involving PLSU may be intraoperative (during surgery) and in the first 24 hours following the procedure. Intraoperative risks and complications may include:
- Minor bleeding from the surgical site
- Vitreous hemorrhage which can resolve spontaneously but may result in preretinal or subretinal fibrosis
- Retinal break, retinal detachment, or vitreoretinopathy, which can be treated with vitrectomy and silicone oil tamponade. Retinal detachments can resolve on their own before a treatment option is considered
Postoperative risks and complications may include:
- Hyphema (collection of blood inside the anterior chamber)
- Recurrent retinal detachment accompanied by proliferative vitreoretinopathy, in patients who had received vitrectomy and silicone oil tamponade treatment for retinal detachment. Further surgery is deemed unfit because it is not visually or anatomically useful
- Cataract development is often mild and may not require surgical intervention in some patients. However, some may require phacoemulsification
- Endophthalmitis (inflammation of intraocular cavities)
- Scleral thinning
- Secondary glaucoma
- Iridodialysis (caused by blunt trauma to the eye)
- Bullous keratopathy
- Posterior synechiae
- Intraretinal or subretinal hemorrhage
- Preretinal fibrosis often in the macular pucker (resection area)
- Tumor recurrence which may necessitate enucleation especially in a blind, painful eye
Aftercare & Recovery
The patient’s intraocular pressure is monitored after surgery to ensure it is stable. Medications to alleviate pain, inflammation, and infection will be prescribed, some of which may be taken for several weeks following the procedure. Patients need a follow-up of up to six years to monitor for recurrence.
Research indicates that partial lamellar sclerouvectomy may offer a primary therapeutic remedy for ciliary body tumors, with good visual outcomes. Final visual acuity attained may be ≥20/40 in children. Although PLSU is a challenging surgical procedure, it can be used to eliminate the problem of intraocular tumors, and possibly, the probability of death in the case of malignant tumors. To save lives, the surgeon may opt for enucleation which rids the body of cancerous cells.
In the case of large or thicker tumors and choroidal involvement of tumors, visual outcomes may be poor. Metastasis in melanoma patients can lead to a recurrence and development of epithelioid cells.