Scleroplasty is a specialized surgical procedure designed to reinforce or repair the sclera, the tough, white outer layer of the eye. This procedure plays a significant role in preserving vision by addressing weaknesses or damage to this protective outer wall.
Understanding Scleroplasty
The sclera forms the supporting wall of the eyeball, helping maintain its spherical shape. This dense connective tissue, commonly known as the “white of the eye,” extends from the clear cornea at the front to the optic nerve at the back. The sclera is primarily composed of robust collagen fibers arranged in an irregular, interlacing pattern, which provides both strength and flexibility to the eye. This protective layer also serves as an attachment point for the extraocular muscles, allowing for eye movement.
The procedure’s general goal is to provide structural support to areas where the sclera has become thinned or weakened. This reinforcement helps to prevent further stretching or bulging of the eye wall. By stabilizing the eye’s shape, scleroplasty aims to protect the delicate internal structures, including the retina, from damaging stresses. This mechanical support is particularly important in conditions where the eye progressively elongates.
Medical Conditions Addressed
Scleroplasty primarily addresses conditions characterized by scleral weakening or excessive elongation. A prominent indication is progressive high myopia, also known as pathological or degenerative myopia. In this condition, the eye elongates beyond a typical length, often exceeding 25.5 to 26.5 millimeters, leading to thinning of the scleral wall and high refractive errors, typically -5 to -7.5 diopters or more. This elongation can cause the posterior part of the eye to bulge outwards, forming a posterior staphyloma, which signifies a weakened area of the sclera.
The thinning and stretching of the sclera in pathological myopia can lead to several severe complications, including retinal detachment and choroidal neovascularization. Scleroplasty aims to stabilize or halt this progressive elongation, thereby reducing the risk of these sight-threatening complications. While less common, scleroplasty may also be considered for scleral thinning resulting from inflammatory diseases or trauma that compromise the eye’s structural integrity.
The Surgical Process
Scleroplasty is typically performed as an outpatient procedure. The surgery is commonly conducted under local or general anesthesia to ensure patient comfort. The primary aim of the procedure is to apply supportive material around the posterior part of the eye to reinforce the weakened sclera.
Various materials have been utilized for this reinforcement, including donor human sclera, which is considered highly compatible. Other materials that have shown promise include deproteinated xenogenic sclera, collagenic sponge, and modified dura mater. Some techniques involve using a discoid xenograft, such as treated bovine pericardium. The material is carefully positioned to encircle or support the thinned areas, particularly at the posterior pole, to counteract the forces causing eye elongation.
Post-Operative Care and Prognosis
Following scleroplasty, patients can expect a recovery period that typically involves mild discomfort, manageable with pain relievers. The use of prescribed eye drops is common to prevent infection and reduce swelling. Patients are usually advised to limit strenuous activities for a short period to allow for proper healing.
The primary goal of scleroplasty is to stabilize the eye and prevent further deterioration of vision, rather than to reverse existing vision loss. Studies have indicated that the procedure can effectively slow the increase in axial length and stabilize refractive errors in cases of progressive high myopia. While the procedure is more commonly performed in some regions, such as Russia and Japan, its long-term efficacy and safety continue to be areas of ongoing research and discussion in the medical community.