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The most common cause of curable blindness worldwide is cataract. It accounts for nearly 75% of blindness in the developing world. Every year about 1 to 2 million cataract cases are added to the global burden, and the number of cataract surgeries performed worldwide accounts for approximately 10 to 12 million. To address this global concern, numerous efforts are underway to reduce the cataract backlog by performing cost-effective manual small incision cataract surgery on the poor and the needy. This has helped in making cataract services available to all. The transition from intracapsular cataract extraction to extracapsular cataract extraction and the manual small incision cataract surgery has transformed outcomes of cataract surgery in terms of visual outcomes, quality of life, and increased surgical acceptance by the patients. Cataract surgery has undergone a massive revolution and technical advancements, and now MSICS has become the surgery of choice in the developing world and phacoemulsification in the developed world. Today is the rollable and accommodative IOL era, which can be implanted through an incision as small as 2 mm. MSICS offers the advantages of being a high-quality surgery, comfort for the patients, less surgical induced astigmatism than extracapsular cataract extraction, no suture-related problems, early rehabilitation, and reduced postoperative visits. MSICS has a short learning curve, is cost-effective, and simple with various indications in nearly all types of cataracts. This activity deals with the anatomy, indications, contraindications, instruments, personnel, technique, complications, and clinical significance of MSICS for the interprofessional team. Objectives: Describe the indications of manual small incision cataract surgery. Outline the potential complications of manual small incision cataract surgery. Summarize the technique of manual small incision cataract surgery. Review the equipment required for manual small incision cataract surgery. Access free multiple choice questions on this topic.

Cataracts are one of the most common causes of reversible blindness worldwide, and cataract surgery is one of the most common ocular surgery performed globally for visual rehabilitation. Vision-related quality of life and visual rehabilitation are essential parameters to determine the success of cataract surgery.[1] Cataract surgery has evolved over the years, and due to advances in surgical technique, instrumentation, and availability of newer drugs, the surgical procedure involves less risk and excellent outcomes.[2] As per the report by WHO, nearly 20 million people are bilaterally blind worldwide.[3] The introduction of phacoemulsification by Kelman in 1967 revolutionized the clear corneal self-sealing incisional surgery.[4] Manual SICS became famous from 1980 onwards, especially in developing countries, due to comparable surgical outcomes in contrast to phacoemulsification, less costly equipment needed,  less time-consuming procedure, and fewer complications in complex cases.[5] Cataract surgery evolved from ECCE to MSICS and then to phacoemulsification. The most significant advantage of MSICS over ECCE is that it is a sutureless surgery with a self-sealing tunnel.[6] An average SICS takes approximately 7 to 10 minutes in expert hands. The surgery steps are detailed below in the activity, along with indications and contraindications.[7] Here we have also described the intraoperative and postoperative complications associated with MSICS. MSICS is still the surgery of choice in high volume cataract settings, developing and underdeveloped countries, and complex cataract cases. However, a lot of modifications have been described like the Mininuc technique (anterior chamber maintainer technique), Ruit technique (V-shaped capsulotomy), Malik technique (anterior chamber maintainer with continuous infusion of viscoelastic), and double nylon loop technique (nucleus trisection technique), but the basic technique remains the same.[6]

Intraoperative Wound Related Incision Position Anteriorly placed incisions have a poor self-sealing mechanism, resulting in wound leak and, against the rule, astigmatism. This is managed by placing 10-0 nylon tunnel sutures. Posteriorly placed incisions lead to a broader tunnel, risk of hyphema due to bleed and premature entry, and difficulty in delivering the nucleus through the tunnel. This is again managed by placing 10-0 nylon tunnel sutures.[43] Incision Length Shorter incisions less than 6 mm are related to nucleus engagement in the tunnel and difficulty in nucleus delivery. Tunnel compression during nucleus delivery can aggravate endothelial trauma, iridodialysis, zonular dialysis, and posterior capsular rent. Large incisions are related to the rule astigmatism and wound leak, which sutures can manage.[43] Incision Depth The incision depth should ideally be one-third of the scleral depth. In highly myopic eyes, with scleral scarring or deep socket, the surgeon may find it challenging to find the correct depth of the incision.[43] Scleral Disinsertion A deep incision may result in separating the upper sclera from the lower sclera and result in disinsertion. If there is no tissue bridge, there is no support for the sclera from the groove to the limbus. This complication is managed with radial sutures to secure the edges of the scleral groove. Scleral disinsertion is prevented by making a partial thickness groove, freehand incision, or a guarded blade. The scleral tunnel roof or floor may also be torn.[17] Button Hole There occurs superficial dissection of the sclera flap. The dissection should be terminated, and then a groove should be made at a deeper plane, and then the tunnel should be continued. Premature Entry This results in from incision at a deeper plane. Once a premature entry is noted, dissection should be stopped as a groove should be made at a correct plane, and then the tunnel should be continued.[7] Descemet Membrane Detachment

There occurs superficial dissection of the sclera flap. The dissection should be terminated, and then a groove should be made at a deeper plane, and then the tunnel should be continued. Premature Entry This results in from incision at a deeper plane. Once a premature entry is noted, dissection should be stopped as a groove should be made at a correct plane, and then the tunnel should be continued.[7] Descemet Membrane Detachment Any iatrogenic or traumatic injury to the DM may result in DM detachment. Sometimes DM stripping may occur when fluid from the cannula or viscoelastic from the paracentesis passes into the corneal stroma and DM and separates the DM. Sometimes the DMD appears as a free-floating membrane and is mistaken as a remnant of the anterior capsule and is aspirated in the Simcoe cannula. This results in DM loss and leaves a permanent corneal opacity. The DMD is managed with the help of air tamponade, and if needed, the tunnel is sutured to prevent the leak of air bubbles.[44] Conjunctival Ballooning Sometimes during block or while hydrating the corneal stroma, the fluid may egress through the stroma into the conjunctiva and result in hooding or ballooning of the conjunctiva. This may impair the anterior chamber visualization and may mask the surgical steps. This is managed by placing a small incision 1-2 mm posterior to the conjunctiva and allowing the fluid to egress.[45] Paracentesis The configuration of the paracentesis is essential as a too anterior paracentesis in the cornea may lead to DM stripping, too far in the sclera will result in bleeding, too small instruments may result in DM stripping, and too large may result in leakage. Capsulorhexis Runaway Rhexis There can be a peripheral extension of the tear and may result in a posterior capsular tear.[46] Capsulorhexis Size A small capsulorhexis may result in difficulty in nucleus prolapse. Difficulty in prolapse may lead to PCR, zonular dialysis, or nucleus drop. A large capsulorhexis may cause a problem with the placement of an IOL. If the rhexis margin is not seen on one side,  the IOL placement will be difficult and may even result in decentration.[22] Hydrodissection Inadequate cortical capsular bag dissection Fluid misdirection syndrome Zonular dialysis PCR Nucleus drop Capsular block syndrome Nucleus Prolapse

A small capsulorhexis may result in difficulty in nucleus prolapse. Difficulty in prolapse may lead to PCR, zonular dialysis, or nucleus drop. A large capsulorhexis may cause a problem with the placement of an IOL. If the rhexis margin is not seen on one side,  the IOL placement will be difficult and may even result in decentration.[22] Hydrodissection Inadequate cortical capsular bag dissection Fluid misdirection syndrome Zonular dialysis PCR Nucleus drop Capsular block syndrome Nucleus Prolapse Difficulty prolapsing the nucleus may result from the small pupil, incomplete hydro dissection, the small size of the rhexis, synechiae, brown cataract, and soft nucleus. This may result in endothelial damage, iridodialysis, zonular dialysis, posterior capsular rent, or nucleus drop.[43] Nucleus Delivery While nucleus delivery, if the tunnel is of inadequate size, it can result in Descemet membrane detachment, endothelial damage, iridodialysis, PCR, and ZD. These complications arise due to small tunnel, ragged tunnel, incomplete hydro dissection, anterior chamber leak, premature entry, or vitreous in the anterior chamber. Hyphema The significant reasons for hyphema can be deeper tunnel incision, iridodialysis, and microbleeds from conjunctival vessels seeping into the anterior chamber. This can be prevented by correct surgical technique and an excellent viscoelastic cover.[43] Iris Damage Injury to the iris can cause a tear, sphincter damage, iridodialysis, and iris prolapse. Sphincter tears can occur in cases with PXF and complications during nucleus delivery. Iridodialysis Iris prolapse Pupillary constriction Zonular dialysis Posterior capsular rupture Retained cortex Nucleus drop Positive pressure Expulsive choroidal hemorrhage Postoperative Immediate Wound leak Descemet membrane detachment Corneal edema Endothelial damage Uveitis Secondary glaucoma Toxic anterior segment syndrome Delayed Corneal decompensation Uveitis Capsular contraction syndrome IOL dislocation IOL subluxation Posterior capsular opacification Irvin Gass syndrome Endophthalmitis Pan ophthalmitis Complications Unique to MSICS Tunnel and Scleral Complications Surgically induced necrotizing scleritis Buttonhole Premature entry Nucleus in tunnel Cortex in the anterior chamber Wound leak Paracentesis leak Exposed suture knots Incorrect suture placement Corneal Complications Corneal edema DMD Striate keratopathy Pseudophakic bullous keratopathy Epithelial defect Recurrent erosions[43]

To achieve a good outcome in cataract surgery following MSICS, the ophthalmic surgeon, the mid-level ophthalmic personnel, the optometrists, the OT staff, and the nurses assisting with IOL power calculation and counseling play a crucial role. A perfect outcome following MSICS is a result of good teamwork.[48]

The nursing staff helps in documenting visual acuity, refraction, lacrimal syringing, intraocular pressure, IOL power calculation, counseling, and assisting in OT. The allied health professionals also help shift patients with systemic comorbidities and play a vital role during any emergency.[48]

The nursing, the allied health staff, and the interprofessional team help in monitoring high-risk patients with systemic comorbidities, monitoring pediatric patients under general anesthesias, intubation, extubation, and vitals of physically ill patients requiring urgent cataract surgery.[48]