Astigmatism After Small Incision Cataract Surgery Versus Phacoemulsification: A Systematic Review of Current Evidence

The current evidence demonstrates that phacoemulsification consistently induces lower surgically induced astigmatism than Manual Small Incision Cataract Surgery because of its smaller incision size and reduced alteration of corneal biomechanics. Consequently, phacoemulsification offers superior refractive predictability, faster visual rehabilitation, and earlier refractive stability. However, advances in MSICS—including temporal incision placement, improved scleral tunnel architecture, and sutureless wound construction—have substantially reduced postoperative astigmatism, resulting in visual outcomes that approach those of phacoemulsification. Although MSICS generally produces slightly higher SIA, the difference rarely affects final best-corrected visual acuity when appropriate refractive correction is provided. From a global public health perspective, MSICS remains an indispensable surgical technique because of its affordability, shorter learning curve, reduced equipment requirements, and effectiveness in managing advanced cataracts. In resource-limited settings, MSICS provides an excellent balance between safety, efficiency, cost-effectiveness, and visual outcomes. The choice between MSICS and phacoemulsification should therefore be individualized, taking into account patient characteristics, pre-existing corneal astigmatism, cataract density, surgeon expertise, available infrastructure, and healthcare resources. Continued refinement of surgical techniques and the adoption of emerging technologies are expected to further improve refractive outcomes and patient satisfaction following cataract surgery.

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