**13. Compressive sutures**

*Eyesight and Imaging - Advances and New Perspectives*

**12. Intracameral gas**

**Figure 5.**

It is considered a treatment of choice for acute hydrops. Gas or air in an anterior

chamber has 2 distinct advantages: first, it aids in the unrolling of the DM, and second, it provides compression of the DM to the swollen stroma [63, 64]. An injection of air was tried but it got absorbed in 3 days without giving enough tamponade to the DM. Hence, a nonexpansile mixture of the expansile gas with air is used to maintain the tamponade effect for a minimum period of 10 days. Sulfur hexafluoride (SF6) and perfluoropropane (C3F8) are commonly used by the corneal surgeons worldwide to produce a prolonged tamponade effect. SF6 (0.1 mL, 20%) was used by Panda et al. in their study of 9 cases that showed only marginal improvement in 3 cases and the remaining 6 cases required reintroduction of the gas twice or more for complete resolution of the corneal edema [63]. Basu et al. performed a comparative study on patients with acute hydrops [64]. One arm of the patients was treated with 14% nonexpansile perfluoropropane (C3F8), wheras the other arm was treated with conventional medical therapy. A faster resolution of the corneal edema was observed in the eyes of patients who were surgically treated, and the improvement was statistically significant. All the patients were advised to rest in a supine position for a period of 10 days to augment the tamponade effect. Histopathological studies on resolved hydrops have confirmed that DM adherence to the stroma is superior with intracameral gas compared with that without any treatment. All authors in the referred studies have recommended the continuation of conventional medical therapy of hypertonic saline eye drops, corticosteroids, and antiglaucoma drugs in the postoperative period. Nevertheless, acute hydrops treated using intracameral gas poses a high risk of pupillary block glaucoma, Urrets-Zavala syndrome, stromal cleft, and accidental seepage of air bubbles into the cornea stroma resembles a 'fish egg' in appearance in a slit lamp experiment. Hence, an inferior surgical iridectomy is recommended to prevent any instances of acute congestive glaucoma. Moreover, the intracameral gas should be introduced along the iris plane and in a single bubble because faulty introduction of the gas may lead to the bursting of the bubble into multiple bubbles that will nullify the tamponade effect and cause accidental damage to the corneal endothelium and

*Combination of compressive sutures with intracameral SF6 gas (Dr.Devi Aiswarya Das).*

**8**

seepage of the bubbles into the stroma.

Full-thickness corneal sutures involving the edematous part of the cornea have facilitated decrease in the corneal edema [30]. Here a 10–0 nylon suture is used to tamponade the Descemet membrane to corneal stroma. Initially a small paracentesis is created at the limbus of cornea followed by injection of intracameral pilocarpine to constrict the pupil. Viscoelastics are injected into the anterior chamber next to protect iris and crystalline lens. A 10–0 nylon suture is introduced at the junction of edematous and non-edematous cornea, the curved needle once enters the anterior chamber is taken out from the farthest end of the needle with a distance equivalent to the length of the needle and is tied over the corneal surface. The knot of a suture is buried into the cornea. Multiple sutures can be applied depending on the extent of the edema. The basic purpose of compressive sutures is not to oppose the torn DM ends but just to provide a support to the DM by bringing it near to the stroma. Once DM is opposed to the stromal endothelial cells, it starts pumping out a fluid from the stroma by active filtration and thereby helps in faster resolution of the corneal edema. Subudhi et al. demonstrated an excellent visual outcome associated with the use of compressive sutures alone in the management of acute hydrops; visual acuity of the patient improved from hand movements to 6/24 by the end of 2 months with a minimal scar at the center and no evidence of any corneal vascularization. Compressive sutures can be applied in a linear manner in case of small hydrops, but if hydrops is large enough to cover nearly all portions of the cornea, then a rectangular pattern involving all the quadrants can be applied. Pads and bandages can be given for a period of 24 hours to prevent any egress of fluid from the anterior chamber and its shallowing. Intracameral antibiotics can be given as prophylactic measures. These sutures stay for a period of 2 to 3 weeks; loosening of the sutures causes loss in the tamponade effect and should be removed in an operating room under strict aseptic precautions. Adverse effects observed are the shallow anterior chamber on Post-Operative Day 1; however, they got resolved in 24 hours without any further intervention. Nonetheless, these patients were advised to perform their routine activity after 5 days of rest. No patients were advised to have a mandatory supine position as in the treatment with intracameral gas injection.
