Author: Claude (AI), from PubMed abstracts · Reviewed by: Dr Mina Abdelmseih · Reviewed: 2026-11-15 · Review due: 2027-11-15

Educational content only. Not personalised medical advice. Clinical decisions remain the responsibility of the treating clinician.

Manual small-incision cataract surgery

Manual small-incision cataract surgery (MSICS) removes the lens through a self-sealing scleral tunnel without a phacoemulsification machine, and is widely used in low- and middle-income countries [S7] [S9]. Systematic reviews of randomised trials find best-corrected vision similar to phacoemulsification at a fraction of the cost, which makes MSICS a key technique for high-volume programmes [S4] [S11].

Key points - Best-corrected visual acuity (BCVA) after MSICS is similar to phacoemulsification; phacoemulsification gives better early uncorrected acuity (UCVA) and less surgically induced astigmatism (SIA) [S3] [S4] [S11]. - MSICS costs much less than phacoemulsification: more than four times less in one trial reported in the Cochrane review [S4], Rs 720.99 ($15.34) vs Rs 1978.89 ($42.10) per case in an Indian costing study [S2]. - A temporal frown incision produces the least SIA; an incision on the steep meridian can neutralise around 1 D of pre-existing astigmatism [S12]. - Intracameral antibiotics are associated with fewer cases of endophthalmitis after MSICS [S7]. - Posterior capsule rupture (PCR) is the commonest intraoperative complication in one Nigerian series and strongly predicts a poor outcome where no vitrector is available [S8].

Evidence last checked: 2026-10-17 (PubMed abstracts).

Red flags

• Posterior capsule rupture without vitrectomy access. In a Nigerian series of 405 MSICS cases, PCR (4.7%) made a borderline or poor outcome (<6/18) 7.0 times more likely; only 26.3% of PCR eyes reached 6/18 or better at final follow-up vs 71.5% without PCR [S8].
• Postoperative corneal oedema and iritis. Extensive intracameral manoeuvres during nucleus delivery increase the chance of both [S9].
• Endophthalmitis. Higher rates have been reported after MSICS than after phacoemulsification [S7]. See Refer when for timing.
• Toxic anterior segment syndrome (TASS). An expert consensus stresses prompt management and a review of operating room protocols [S10].

Recognise it: when MSICS is a good choice

• An international expert panel (AAPPO, 2025) agreed that manual surgery has a significant role in eyes with large, dense nuclei and in populations that need low-cost, high-volume surgery, and preferred a manual sutureless approach where appropriate [S10].
• Hard brunescent cataracts form a sizeable proportion of cases in developing countries, and MSICS is instrumental for them [S9].
• In a masked RCT of 400 eyes in India, both techniques were safe and effective [S1].

Confirm it: outcomes to expect

• Cochrane review (2013), 8 RCTs, 1708 participants (India, Nepal, South Africa): BCVA 6/18 or better at 6 to 8 weeks did not differ (RR 0.99, 95% CI 0.98 to 1.01); UCVA 6/18 or better favoured phacoemulsification (RR 0.90, 95% CI 0.84 to 0.96). The review was underpowered for rare outcomes such as BCVA below 6/60 and lacked long-term data [S4].
• Meta-analysis of 6 RCTs (1315 eyes): no difference in BCVA, endothelial cell loss or complications; phacoemulsification gave more eyes with UCVA 6/9 or better and less SIA [S3].
• Meta-analysis of 11 comparative studies (76,838 eyes): comparable UCVA and BCVA at 6/18 and 6/60, similar endothelial cell loss and complications; MSICS took less time, cost less than half, gave better uncorrected near vision and was safer during the learning phase [S6].
• Umbrella review (2025) of 4 systematic reviews: no consistent BCVA difference at any time point; early UCVA advantages for phacoemulsification were not maintained; complication profiles broadly similar [S11].
• RCT detail [S1]: presenting acuity 6/18 or better at 6 weeks in 81.08% (phacoemulsification) vs 71.1% (MSICS); best-corrected 98.4% in both. Posterior capsular rents: 7 with phacoemulsification vs 12 with MSICS; more day-1 corneal oedema with phacoemulsification.
• MSICS vs extracapsular extraction (ECCE): a Cochrane review (2014) of 3 trials (953 participants) found more MSICS patients achieved good unaided acuity in two trials and less SIA than ECCE, but not more than 50% achieved good functional vision in those two trials; data were insufficient for meta-analysis [S5].

Manage it: technique and safety

Before acting on this section, check the national and local guidelines, product information and regulatory approvals that apply where you practise. See the medical disclaimer.

Tier A (primary care / no specialist)

• Identify people with cataract and refer them to a surgical programme; MSICS is the technique many such programmes use for high-volume, low-cost surgery [S4] [S10].
• After surgery, refer any patient with pain, worsening vision or a very red eye using the timings in Refer when.

Tier B (general eye clinic)

• Incision. Pooled mean SIA was 1.10 D for superior and 0.82 D for temporal incisions; straight incisions caused more SIA than frown incisions (temporal 1.02 D vs 0.72 D). With no pre-existing astigmatism, a temporal frown incision is preferred; around 1 D of astigmatism can be neutralised by placing the incision on the steep meridian [S12].
• Tunnel and capsule. A poorly constructed sclero-corneal tunnel or a small capsulorhexis hampers nucleus extraction [S9].
• Learning curve. Replicable outcomes need a significant learning curve [S9]; MSICS was safer than phacoemulsification during the learning phase in one meta-analysis [S6].
• Infection prophylaxis. A meta-analysis of 12 studies (1,494,307 eyes) found an endophthalmitis risk ratio of 2.94 (95% CI 1.07 to 8.12) in eyes without intracameral antibiotics [S7]. The specific drug and dose are not given in the abstract: follow local protocols and formularies.

Tier C (specialist centre)

• Provide vitrectomy capability and referral pathways for PCR: outcomes after PCR were poor in a centre without an automated vitrector [S8].
• Audit outcomes and complications; the consensus panel advised reassessing operating room protocols when TASS occurs [S10].

Refer when

Pitfalls

• Judging MSICS by unaided acuity alone: BCVA is equivalent, and the early UCVA gap narrows [S4] [S11].
• Using a straight superior incision by default; temporal frown incisions produce less SIA [S12].
• Starting a high-volume service without intracameral antibiotic prophylaxis [S7].
• Underestimating the impact of PCR where vitrectomy is unavailable [S8].
• Assuming MSICS is only for low-income settings: experts recognise a role for dense nuclei anywhere [S10].

Evidence notes

• The randomised trials were mostly conducted in India, Nepal and South Africa, with unclear masking and follow-up, and most reported outcomes only at 6 to 8 weeks [S4] [S5].
• The SIA meta-analysis had very high heterogeneity (I² above 97%), and the effect of sutures was not assessed [S12].
• The intracameral antibiotic meta-analysis pooled observational studies; the abstract does not name the antibiotic or dose [S7].
• The consensus statements reached agreement on only about 60% of items, reflecting variation in practice [S10].
• Not covered by these sources: step-by-step nucleus delivery techniques, anaesthesia, long-term posterior capsule opacification, and paediatric MSICS.

Related articles

• Phacoemulsification: outcomes and techniques
• Effective cataract surgical coverage and outcomes
• Complications of cataract surgery

References

See the numbered source list below. Each marker [S#] links to its PubMed and DOI record.