Dr. Arshed Malik

Aim

Audit of 371 consecutive adult phacoemulsification cataract surgeries; along with a comparison of results against published benchmark datasets/ guidelines(CND).

Introduction

Small incision cataract surgery is considered the most common operation in the NHS.⁽¹⁾ Cataract surgery is generally a safe and successful procedure; however, complications can occur at any stage and this, in turn, can affect the final visual outcome.⁽²⁾ Published national datasets and guidelines were designed to provide benchmark standards for surgeons and departments to judge their performance. ^{(1, 2)}

Methods

A retrospective data collection and analysis for cataract procedures performed by a single surgeon Arshed Malik Data of 371 sequential patients, performed in theatre sessions from 15/10/2021 to 20/07/2023. The theatre sessions were held at Blackpool Victoria Teaching Hospitals, as a locum consultant post, and all procedures were independently performed. The standard surgical setting at Blackpool Victoria Teaching Hospitals includes ceiling mount Zeiss microscope, surgical microscope and Alcon Oris and Stellaris( Millenium) platform for cataract surgery. All procedures were performed under a local anesthetic, mostly topical Proxymethacain or Sub-tenon injection of 3-5 ml lidocaine 2%, given by the same surgeon. The phacoemulsification technique includes clear cornea 3-step incision using 2.65 mm keratome, at the axis of the steepest K whenever possible. Primary Chop and Stop was the method of choice for all patients (Phaco-settings: Peristaltic pump, Vacuum: 350 mmHg, Phaco-power: 35 – 45 % and flow-rate: 35ml/min). Most of the patients were from Blackpool Victoria Teaching Hospitals, last 83 patients were from Royal Edward Albert Infirmary. The Phaco-machine used at Royal Edward Albert was Bausch & Lomb. ( MediSoft software was used for all data recording and analysis.) Collected data

Age at surgery
Gender
Pre-operative visual acuity (documented in Snellen’s notation)
Pre-operative Spherical equivalence
Pre-operative risk factors and co-pathology:

Brunescent Cataract
Zonular Dehiscence
Narrow Pupil
Previous Ocular Surgery (Trabeculectomy, Retinal detachment)
AMD/ DR/ Amblyopia/ERM

Effective Phaco-time
Intra-Operative complication
Post-operative visual acuity (documented in Snellen’s notation)
Post-operative error of refraction (all transposed to a negative cylinder format)
Post-operative Spherical equivalence

Results

Pre-Operative: 371 patients were enrolled. The mean age at surgery was 75.6 years (+/- 9.07), the age range was 42- 95 years. Pre-operative best corrected visual acuity ranged from counting fingers to 6/12.

Risk factors and co-pathology	Frequency
Brunescent Cataract	8.3%
Zonular Dehiscence	1.8%
Narrow Pupil	7.3%
Previous Ocular Surgery (Trab./ RD Sx)	1.8%
AMD/ DR/ Amblyopia	7.3%

Post-operative: Encountered Post-Operative complications were Cystoid Macular Oedema in (1.7%) patients, Corneal Edema in (1.1%) patients Overall 98.3 % of patient had improved post-operative visual acuity. 333 (90%) patients had 6/12 or better post-operative visual acuity and 223 out of 371 (60.2%) patients 6/6 or better post-operative visual acuity. Post-operative refraction with deviation of +/- 1.0 D is 90.5%. Post operative spherical equivalence from -1.00 to + 1.00 is 93.53%

POST OF BCVA>/=6/12	THIS AUDIT	UK EPR CND 07
All Patients	90%	91%
With Ocular Co Morbidity	88%	82%
Without Ocular Co Morbidity	91%	94.7%

Discussion

Results were compared against the “The Cataract National Dataset electronic multicentre audit” by Jaycock et al 2009⁽¹⁾ Overall 98.3% of patients had improved visual acuity of 3/60 or better. Topical anesthesia was used in 89.0% patients, and sub-tenon anesthesia was given to 8.0% patients, the rest of the patients had General anesthesia. There was no operative complication in 98.3% of patients. PC rupture was noticed in 4 (1.1%) and had anterior vitrectomy(Sulcus IOL), zonular dialysis in 5(1.3%), supra-choroidal hemorrhage, and Hyphema was in 0.1%. Post operative refraction deviation of +/- 1.0 D was 90.5%. (As per Medisoft)

Number of Cataract Surgeries	Posterior Capsular Rapture Case Complexity Index (%)	Post-op Visual Acuity 6/12 OR better (%)	Post-op Visual Acuity 6/6 OR better
371	1.1%	90%	60.2%

Conclusion

The Post-op Visual Acuity and refractive outcomes were better than Cataract National Dataset, the complication rate is comparable to CND. The possible cause of slightly reduced visual acuity is pre-operative co-pathology and also incision axis. But post op refraction and spherical equivalence are according to National Data set, which confirms the cause as co-pathology rather incision axis. No changes to surgical practice were made except, onward incision sight should be on steep axis K2 either superior or temporal incision. And also to consider the use of Toric lenses to reduce astigmatism. The possible cause of increased post-operative CMO in this case series may be due to a higher number of patients with brunescent cataracts (8.3%), zonular dehiscence (1.8%), and narrow pupils (7.3%). However, this needs to be investigated in a prospective audit.

References

Jaycock P, Johnston RL, Taylor H, Adams M, Tole DM, Galloway P, Canning C, Sparrow JM. The Cataract National Dataset electronic multi-center audit of 55,567 operations: updating benchmark standards of care in the United Kingdom and internationally. Eye 2009: 23: 38-49.
The Royal College of Ophthalmologists. Cataract surgery guidelines. September