Manual Small-Incision Cataract Surgery (MSICS)

Step 1 — Patient Preparation & Anaesthesia

• Topical, peribulbar, or sub-Tenon's anaesthesia is administered.
• The eye is cleaned and draped; a lid speculum is inserted.
• Pupil is maximally dilated with mydriatic drops.

Step 2 — Conjunctival Flap

• A fornix-based conjunctival flap is created at the superior limbus, exposing the bare sclera.
• Wet-field cautery is applied to achieve haemostasis.

Step 3 — Scleral Groove (Incision)

• A partial-thickness (approximately 300 µm deep) frown-shaped or straight scleral groove is made ~1–2 mm behind the limbus using a crescent blade.
• The groove spans ~6–7 mm — wide enough to allow nucleus delivery without phacoemulsification.

Step 4 — Sclero-Corneal Tunnel Dissection

• A crescent blade dissects a lamellar tunnel forward into clear cornea, creating a self-sealing sclerocorneal tunnel.
• The tunnel must be of uniform depth — too shallow risks button-holing; too deep risks perforation.
• A keratome then enters the anterior chamber through the internal lip of the tunnel.

Step 5 — Anterior Capsulotomy (Capsulorhexis)

• Trypan blue (0.06%) is injected to stain the anterior capsule, aiding visibility — especially important with white/mature cataracts.
• An ophthalmic viscosurgical device (OVD/viscoelastic) fills the anterior chamber to maintain depth.
• A continuous curvilinear capsulorhexis (CCC) is performed using a needle or capsulorhexis forceps, creating a circular opening in the anterior capsule.

Step 6 — Hydrodissection & Hydrodelineation

• Balanced salt solution (BSS) is injected under the anterior capsule to free the lens nucleus from its cortical attachments (hydrodissection) and to delineate the nucleus from the epinucleus (hydrodelineation).
• This allows free rotation and subsequent delivery of the nucleus.

Step 7 — Nucleus Prolapse & Expression

• The nucleus is tilted and prolapsed into the anterior chamber using instruments (e.g., Sinskey hook, lens dialer, or a vectis).
• A lens vectis (wire loop) or an irrigating vectis is inserted beneath the nucleus in the anterior chamber.
• The nucleus is manually expressed out through the scleral tunnel by gentle posterior pressure at the limbus combined with upward lift of the vectis — the "sandwich" or "tumbling" technique.
• OVD protects the corneal endothelium throughout this step.

Step 8 — Cortical Aspiration

• Residual cortex is removed using a Simcoe cannula (two-way irrigation-aspiration cannula).
• Irrigation maintains anterior chamber depth while aspiration removes lens remnants from the capsular bag.
• Thorough cortex removal prevents posterior capsule opacification (PCO).

Step 9 — IOL Implantation

• The capsular bag is refilled with OVD.
• A posterior chamber intraocular lens (PCIOL) — typically a rigid PMMA lens — is implanted into the capsular bag.
• PMMA lenses are used because they can be delivered through the larger (6–7 mm) MSICS tunnel without folding; foldable IOLs can also be used.

Step 10 — OVD Removal & Wound Closure

• OVD is thoroughly irrigated and aspirated from the anterior chamber.
• The anterior chamber is reformed with BSS.
• The self-sealing tunnel architecture usually makes suturing unnecessary; however, a 10-0 nylon suture may be placed if the wound is not watertight.
• The conjunctival flap is repositioned and secured (often with cautery or a single suture).

Step 11 — Postoperative

• Subconjunctival antibiotic/steroid injection or topical drops instilled.
• Eye pad and shield applied.

Key Advantages of MSICS vs. Conventional ECCE vs. Phacoemulsification

1. Bipolar diathermy forceps applied to conjunctival vessels

2. General vs. modified scleral incision — haemostasis comparison

• Left column (general): Sclera is incised first → bleeding occurs → bipolar cautery is applied reactively to the bleeding wound.
• Right column (modified/preferred): Sclera is partially dissected → thermal cautery is applied prophylactically to the exposed bed → pre-suture is placed → full-thickness incision is then made → the open wound is nearly bloodless.

3. Exposed sclera after conjunctival flap — pre-haemostasis field

Clinical notes on haemostasis in MSICS

Side Port Entry in Cataract Surgery

Where it is made

• Placed approximately 60° to the left of the main incision (for right-handed surgeons); some surgeons prefer two side ports placed ~180° apart.
• Made in clear cornea at the limbus, using a 15° micro-vitreoretinal (MVR) blade or a side-port keratome.
• Self-sealing — the tunnel architecture means it closes without a suture once the instrument is removed.

How it is made

1. The MVR blade is held at a low angle (~20°) to the corneal surface.
2. It is advanced through the corneal stroma in a bevelled, stepped fashion — creating a valve-like tunnel that self-seals under IOP.
3. The entry is short (1–1.5 mm tunnel length).

What it is used for

Intraoperative views

In MSICS specifically

• Injecting OVD/viscoelastic before capsulorhexis
• Inserting the AC maintainer to keep the chamber formed during nucleus expression
• Passing a second instrument (e.g., Sinskey hook) to assist nucleus prolapse into the anterior chamber