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Ophthalmic surgery in New Zealand: analysis of 410,099 surgical procedures and nationwide surgical intervention rates from 2009 to 2018



Surgical intervention rates (SIR) provide a proxy measure of disease burden, surgical capacity, and the relative risk-benefit ratio of surgery. The current study assessed decade trends in ophthalmic surgery and calculated SIRs for all major classes of commonly performed ophthalmic procedures in New Zealand.


Retrospective population-based analysis of all ophthalmic surgical procedures performed in New Zealand from 2009 to 2018. National and regional datasets from public and private health sectors and industry were analysed. SIRs were calculated for all major ophthalmic procedures, and subgrouped by patient demographics.


There were 410,099 ophthalmic surgical procedures completed with a 25.3% overall increase over 10 years. Procedures were mostly government-funded (51%, n = 210,830) with 71% of patients aged over 64 years. Cataract surgery (78%, n = 318,564) had the highest mean SIR (703/100,000/year) and increased by 25% during the study period, consistent with population growth in the over 64 years old age group. Vitrectomy surgery had the second highest mean SIR (67/100,000/year) and increased by 50%, well above national population growth during the study period. Other SIRs included conjunctival lesion-biopsy (38/100,000/year), glaucoma (33/100,000/year), strabismus (20/100,000/year), dacryocystorhinostomy (10/100,000/year), and keratoplasty surgery (4/100,000/year).


This comprehensive review of New Zealand ophthalmic surgery reports increasing SIRs that cannot be explained by population growth alone. Cataract surgery numbers increased year on year consistent with the increase in the over 64 years old population. Vitrectomy surgery growth exceeded that of the national population, including those over 64 years.

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Fig. 1: Summary of all included ophthalmic procedures performed per surgical category in New Zealand from 2009 to 2018 according to source of funding.
Fig. 2: Frequency of ophthalmic procedures over time by funding source.
Fig. 3: Age distribution for ophthalmic government-funded procedure categories in New Zealand.
Fig. 4
Fig. 5

Data availability

Data for all government-funded ophthalmic procedures from 2009 to 2018 fiscal years are available from the New Zealand Ministry of Health. Private-funded data on ophthalmic surgical procedures was obtained by personal communication from New Zealand’s largest single private healthcare insurer, industry records from intraocular lens implant sales, vitrectomy packs and New Zealand National Eye bank keratoplasty recipient numbers. See Supplementary Table 2 for dataset annual summaries.


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Thank you to the Ministry of Health, New Zealand Eye Bank, PricewaterhouseCoopers, Hoya, Alcon and Dorc.s.


RH’s Clinical Research Fellowship was partially funded by The Waikato Eye Foundation and The University of Auckland.

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Authors and Affiliations



RH, SG and JM conceived and designed the presented study and performed the data collection. HW performed the data analysis. RH wrote the manuscript. SG, HW and JM provided critical review of the manuscript.

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Correspondence to James McKelvie.

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Supplementary information


Supplemental Table 1. List of ICD-10 procedure descriptions that met the inclusion criteria. All other ICD-10 codes / descriptions excluded


Supplemental Table 2: Annual number of all included government-funded, private-funded private (main insurer) and private (other) procedures in New Zealand from 2009-2018

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Hossain, R.R., Guest, S., Wallace, H.B. et al. Ophthalmic surgery in New Zealand: analysis of 410,099 surgical procedures and nationwide surgical intervention rates from 2009 to 2018. Eye (2022).

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