Manual Small Incision Cataract Surgery (MSICS): Steps and Pitfalls
Last updated: November 2026
Manual small incision cataract surgery (MSICS) delivers the whole nucleus through a self-sealing sclerocorneal tunnel without phaco power. It is fast, cheap and excellent for mature and brunescent cataracts, which is why it remains a core skill in India.
Indications and advantages
- Mature, white, brunescent and hypermature cataracts; high-volume and outreach surgery; where phaco machines are unavailable.
- Trials in Nepal and India showed similar visual outcomes to phaco at much lower cost; MSICS is faster for dense cataracts.
- Disadvantages: larger incision (more surgically induced astigmatism, about 1 D), slower visual recovery than phaco.
Steps
| Step | Key points |
|---|---|
| Conjunctival peritomy and cautery | Superior or temporal; temporal reduces induced astigmatism |
| Scleral incision | Frown or straight incision 6–7 mm long, about 1.5–2 mm behind the limbus, partial thickness |
| Sclerocorneal tunnel | Crescent blade dissection 1–1.5 mm into clear cornea, with side pockets (funnel shape: wider inside) |
| Side port and entry | Enter the chamber with a keratome under viscoelastic |
| Capsulotomy | Large continuous curvilinear capsulorhexis (about 6 mm) or can-opener/envelope; trypan blue for white cataracts |
| Hydrodissection and prolapse | Free the nucleus and prolapse it into the anterior chamber |
| Nucleus delivery | Irrigating vectis, fish-hook, phaco-sandwich or viscoexpression |
| Cortex and IOL | Simcoe cannula for cortex; rigid or foldable PCIOL in the bag; check the tunnel is self-sealing |
Complications and fixes
| Complication | Prevention or fix |
|---|---|
| Premature entry or buttonholing of the tunnel | Correct blade depth and angle; start a new tunnel nearby if needed |
| Iris prolapse, iridodialysis | Proper tunnel architecture, enough viscoelastic, avoid shallow chamber |
| Descemet detachment | Careful entry; air or gas tamponade |
| Endothelial damage during delivery | Viscoelastic cushion, controlled delivery |
| PCR and vitreous loss | See the PCR page; avoid pushing on the posterior capsule during prolapse |
| Induced astigmatism | Temporal or on-axis tunnel, frown incision |
Where residents slip
- A tunnel too short or too thin (leaks, iris prolapse).
- Too small a capsulotomy for nucleus prolapse.
- Pressing on the globe during delivery without a viscoelastic cushion.
Test yourself: flip cards
Related: Phacoemulsification Step by Step: A Beginner's Guide, Posterior Capsule Rupture, Lens-Induced and Secondary Glaucomas: Phacomorphic, Phacolytic, Neovascular and More.
Key sources
- Ruit S, et al. A prospective randomized clinical trial of phacoemulsification vs manual sutureless small-incision extracapsular cataract surgery in Nepal. Am J Ophthalmol. 2007;143:32-38
- Gogate P, et al. Manual small incision cataract surgery: a review. Indian J Ophthalmol. 2022
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