Management of Scleral Perforation

General Management Strategies

Although much has been written about this condition, no single method has been universally accepted as optimal in the treatment of scleral perforation. Because perforation of the sclera is often a manifestation of a systemic disease process, the first step in management is identification and treatment of the underlying condition, if present. Some of the conditions associated with scleral perforation are listed in Box 151.1 . For perforations that result from infectious diseases, appropriate microbiologic studies and effective antimicrobial therapy should be instituted before or concurrently with surgical management. Similarly, appropriate local or systemic immunosuppression must accompany the therapy of perforations related to inflammatory conditions. If management of the underlying disease is not instituted or is not successful, the processes that led initially to the scleral defect will continue and lead to either failure of the intervention or to the development of new areas of scleral disease.

Once a scleral perforation has occurred, the physician has several repair options. If there is a small scleral defect without uveal prolapse, no therapy may be necessary for the perforation per se , as long as the factors that led to the process are either under control (infectious or inflammatory diseases) or no longer operative (trauma). For large perforations, surgical repair, either primary closure or patch grafting, may be required. Before surgery, the patient should be examined carefully to determine the location and extent of the defect and the condition of the surrounding tissues. This evaluation permits the surgeon to determine the need for and the approximate size of the patch, if required, and permits the selection of the optimal patch material. For example, when dealing with a perforation involving the limbus, the patch should conform to the surrounding ocular architecture to prevent dellen formation or unwanted keratorefractive sequelae. The preoperative examination should also identify potential intraoperative complications that may be encountered during the procedure, such as uveal or vitreous prolapse. The recognition of these conditions enables the surgeon to have available the equipment and assistance needed to obtain the best operative result.

Anesthesia for Scleral Perforations

The options for anesthesia must also be considered. Topical anesthesia is associated with the least systemic stress and risk of inadvertent injury to the globe. If appropriate, this method may be ideal for small, anteriorly located defects. Unfortunately, these types of perforations are unusual, and most cases require more extensive conjunctival and Tenon capsule dissection and are located too far posteriorly to allow adequate anesthesia with topical agents alone. In these cases, retrobulbar or peribulbar anesthesia may be more appropriate. This approach has the advantages of excellent regional anesthesia and akinesia with minimal cardiac and respiratory stress. These factors may be important in patients who are systemically ill, especially those with perforations resulting from rheumatoid arthritis. The major risks of retrobulbar injection in the setting of scleral thinning or perforation are related to the injection itself. Any volume of anesthetic agent injected into the orbital space results in increased intraorbital pressure, which is transmitted directly to the globe. This increase in intraocular pressure may cause an extension of the ruptured area or may lead to additional ruptures in areas of thinned sclera. The uvea may also be prolapsed (or further prolapsed) through a new or existing scleral defect as a result of increased intraocular pressure. In addition to the hydraulic effects of retrobulbar injection, the passage of the needle near the globe may also produce complications. Patients with scleral perforation caused by necrotizing scleritis or scleromalacia may have areas of scleral thinning and staphyloma formation posteriorly, which can be injured by the retrobulbar needle. These potential problems notwithstanding, many large and complex scleral perforations have been repaired successfully using local anesthesia.

The third anesthetic choice is general anesthesia. General anesthesia has several advantages over the other options. General anesthesia results in minimal increases in intraocular pressure, produces optimal akinesia and anesthesia, and permits operative intervention at multiple sites (i.e., harvesting fascia lata or periosteum for patch materials). General anesthesia, however, is not benign in patients with a significant underlying illness.

Surgical Repair of Scleral Perforations