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Home , Cataract surgery, Phacoemulsification

LEARNING : THE -IN-TRAINING

H. TABANDEH', B. SMEETS", M. TEIMORy2 and H. SEWARD" Croydon and London

SUMMARY gressive evolution. Advances in the design of

With the increasing trend towards phacoemulsification a implants and instrumentation. introduction of viscoelas­ perceived increased rate during the learn­ tics and modification of the surgical techniques on the ing curve gives rise to a dilemma as to the best stage at basis of further experience have refined the procedure. which a surgeon-in-training can safely learn the tech­ However, despite its refinement and improved safety, nique. We prospectively analysed the complications and there is still an increased complication rate during the visual outcome of the first 160 phacoemulsification pro­ learning period.56 Allinson et al.� and Cruz et al.5 have cedures performed by three -in-training. The documented complications that occurred whilst surgeons­ main outcome measures included posterior capsule tear, in-training were learning phacoemulsification. The inci­ vitreous and nuclear loss, surgical re-intervention rate dence of complications, together with the potential to and visual outcome. Posterior capsule tear occurred in 7 inflict greater damage, give rise to a dilemma as to the best (4.4 %) and vitreous loss in 6 (3.8 % ) . No nucleus was stage at which a surgeon-in-training can start learning lost in the vitreous. Surgical re-intervention was required phacoemulsification. in 1 . Best corrected was 6112 or better in In United Kingdom the registrar grade contributes sig­ 88 % of eyes. These results compare favourably with nificantly to the total number of operations that reports of surgeons-in-training learning extracapsular are performed annually. The complication rate and visual surgery and also with recently reported phacoemulsi­ outcome achieved by the junior surgeon has implications fication series. This study indicates that with careful case for the overall morbidity associated with selection and supervision phacoemulsification can be a as well as for surgical training in this country. However, safe procedure. there are no reports on the surgical complications when With the advent of small-incision cataract surgery phacoe­ phacoemulsification is performed by the registrar. mulsification is enjoying a second wave of popularity. A This report documents the operative and immediate survey of the American Cataract and Refractive Surgery post-operative complications as well as the visual out­ Society showed phacoemulsification to be preferred to come of all phacoemulsification procedures that were per­ extracapsular cataract surgery by 52% of the members.' formed during the learning period of three surgeons­ The United Kingdom practice is also rapidly changing in-training. towards phacoemulsification. Phacoemulsification is based upon a different principle PATIENTS AND METHODS and involves different techniques from that of extracap­ Data were collected prospectively on the first 160 phacoe­ sular cataract surgery. In order to perform phacoemulsifi­ mulsification procedures performed by three ophthal­ cation the surgeon needs to acquire new surgical skills. mology registrars over a period of 1 year. The main During the period of gaining experience in these new tech­ outcome measures included posterior capsular tear, zon­ niques there may be a higher incidence of complications. ular dehiscence, vitreous loss, surgical re-intervention and Kelman2 reported a 16% incidence of vitreous loss in the the final corrected visual acuity. early days of phacoemulsification. Since its introduction by Kelman in the 1960s the technique has undergone pro- Patients

From: 1St George's Hospital, London; 'Croydon Eye Unit, Croydon, Patients who were admitted for cataract surgery were UK. assessed pre-operatively with regard to their suitability for Correspondence to: H. Tabandeh. MRCP. FRCOphth, Professorial Unit, Institute of , Moorfields Eye Hospital. London phacoemulsification. Patients with only eye, advanced ECIV 2PD. UK. nuclear sclerosis, poorly dilating and significant

Eye (1994) 8, 475-477 © 1994 Royal College of Ophthalmologists 476 H. TABANDEH ET AL.

corneal opacities were considered unsuitable for phacoe­ Table I. Incidence of capsular lesions and vitreous loss in 160 phaco­ mulsification during the learning period of the registrars emulsification procedures and were either operated on by a senior surgeon or under­ No. of cases Percentage went planned extracapsular cataract surgery. Isolated posterior capsule lesion I 0.6 Isolated zonular lesion I 0.6 Surgeons Vitreous loss 6 3.8 Three surgeons-in-training were involved in the study. Surgical re-intervention 2 1.2 Each was in the fourth year of ophthalmology training and had performed over 150 cases of extracapsular surgery Table II. Other complications of 160 phacoemulsification procedures before undertaking phacoemulsification. Prior phacoe­ No. of cases Percentage mulsification teaching included attending lectures and wet Corneal oedema I 0.6 laboratories and assisting in phacoemulsification proce­ Peaked I 0.6 dures. Various stages of the procedure such as capsulor­ Minor IOL decentration I 0.6 hexis, and automated irrigation and Retraction of I 0.6 Localised choroidal haemorrhage I 0.6 aspiration were practised during extracapsular cataract prolapse o o surgery. The procedure was supervised by two advanced Major IOL decentration o o phaco surgeons and feedback given during and following Nucleus loss o o o o the procedures. IOL. . Surgical Technique Iris prolapse, major lens implant decentration, loss of One hundred and fifty-four cases (96%) were performed nucleus and retinal detachment were not encountered. with the patient under local anaesthesia and 6 patients Eighty-eight per cent of all patients achieved a cor­ had a planned general anaesthetic. A superior rectus bri­ rected visual acuity of 6/12 or better. When cases with pre­ dle suture was used to fix the in all cases. An infer­ existing ophthalmological disease were excluded, 94% ior suture was employed when considered necessary. A 3 had a final corrected visual acuity of 6/12 or better. Of the mm phacoemulsification incision was made superiorly, 20 patients whose vision could not be improved to beyond initially within the anterior , moving posteriorly as 6/12, 10 had diabetic maculopathy, 4 age-related macular more experience was gained. The incision was later degeneration, 4 cystoid macular oedema and I corneal extended to 5.5 or 6 mm for the insertion of lens oedema. There was I case of previously unsuspected 0' implants. A second stab incision was made at 2 clock. ischaemic optic neuropathy. Continuous curvilinear capsulorhexis, hydrodissection and in-the-bag phacoemulsification with nuclear fracture DISCUSSION was performed in all cases. Wound closure was per­ Phacoemulsification is now a well-established method of formed with a I % nylon suture in a bootlace or inter­ cataract surgery. I It is generally agreed that uncomplicated rupted configuration. A viscoelastic material was used in phacoemulsification achieves good visual results and is every procedure. A phacoemulsification machine incor­ associated with reduced surgically induced astigma­ porating a Venturi pump system was employed through­ tism.us In the United Kingdom there has been a progres­ out the study. sive change towards small-incision cataract surgery in recent years. The change initially started at the level of the RESULTS experienced consultant surgeon. However, with the One hundred and sixty patients with a mean age of 74.9 increased availability of equipment and expertise the pro­ years (range 56-93 years) were included in the series. Two cedure is now routine in many departments. As a result surgeons performed 55 operations each and one surgeon registrar-grade surgeons are performing phacoemulsifica­ performed 50 procedures. Isolated posterior capsular tear tion at an increasing rate. Various reports have studied the occurred in I case and zonules were ruptured in another. complications and visual outcome of this procedure in the Posterior capsule tear or zonular dehiscence leading to hands of ophthalmology residents in the United States.4.5 vitreous loss occurred in 6 patients (3.8%) (Table I). Pos­ To our knowledge there are no reports in the literature con­ terior chamber lenses were implanted in all but I eye; in cerning the complications resulting from registrars perfor­ this case secondary lens implantation at a later date was ming phacoemulsification in Britain. considered desirable. Re-intervention was necessary in 2 Reports of vitreous loss during the learning curve patients and included anterior and reposition­ period of experienced and novice ophthalmic surgeons ing of the lens implant in 1 case and the secondary lens from the early days of phacoemulsification suggested an implantation. increased complication rate. Kelman" reported a 16% inci­ Other complications included peaked pupil, minor dence of vitrous loss during the learning period. A similar intraocular lens decentration, retraction of capsulorhexis figure was reported by other surgeons. Improvements in and central corneal oedema (Table II). A localised chor­ the design of surgical instruments, introduction of vis­ oidal haemorrhage occurred in I patient which resolved coelastics, continuous curvilinear capsulorhexis, hydro­ within 6 weeks without any residual visual impairment. dissection and improved lens implant design have all LEARNING PHACOEMULSIFICATION 477 contributed to making phacoemulsification a safer pro­ microsurgery as a whole, as well as theoretical knowledge cedure. The technique has evolved as the cumulative about phaco techniques, instruments and the machine are experience of the experts increases. There is now a larger important first steps. Some manoeuvres such as hydrodis­ number of experienced phaco surgeons and teachers, mak­ section, capsulorhexis and automated irrigation and aspir­ ing direct supervision and teaching possible. Not surpris­ ation can be practised during extracapsular surgery. Good ingly, more recent reports indicate a lower incidence of case selection helps avoid difficult cases which should complications. In 125 procedures Pedersen6 found a 2.1% really be left for the advanced surgeon, thus reducing incidence of vitreous loss and a 4.9% incidence of pos­ unnecessary morbidity. Finally, close supervision by an terior capsule tear. Kershner9 reported an 8% capsular tear experienced phaco surgeon is important in order to avoid rate in 1000 cases using 'can-opener' and serious complications and to improve surgical technique 4% using capsulorhexis. Allinson et al. found a vitreous by means of feedback. loss incidence of 14.7% in operations performed by third In conclusion, this study documents an acceptable year ophthalmology residents learning phacoemulsi­ complication rate during the phacoemulsification learn­ fication. Cruz et at." reported a vitreous loss rate of 5.5% ing period of registrars, indicating that teaching of this and posterior capsule tear rate of 9.9%. Other studies1o-u procedure to a surgeon-in-training can be safe provided demonstrated a rate of vitreous loss during the residents' there is a well-structured surgical training programme, learning period for extracapsular surgery that is similar to adequate experience in extracapsular surgery and that of phacoemulsification. supervIsIon. In this series the rate of vitreous loss was 3.8% and, overall, posterior capsular tear occurred in 5.6% of the Key words: Phacoemulsification. Surgeon-in-training, Surgical compli­ cases. Eighty-eight per cent of all patients achieved a cor­ cation. Vitreous loss. rected visual acuity of 6/12 or better. When patients with pre-existing ophthalmological disease were excluded, REFERENCES 94% had a final corrected visual acuity of 6/9 or better. As I. Learning DY. Practice styles and preferences of ASCRS reduced surgically induced with phacoemul­ members: 1990 survey. J Cataract Refract Surg 1991; 17: sification is already well documented, analysis of astig­ 495-502. matism was not included in the present report. 2. Kelman CD. Symposium: phacoemulsification. Summary This series compares favourably with other reports of of personal experience. Trans Am Acad Ophthalmol Otolar­ the complications of phacoemulsification performed by yngol 1977;78:0P35-8. 3. Seward HC, Dalton R, Davis A. Phacoemulsification during surgeons-in-training.4.5 One factor may be the greater pre­ the learning curve: risk/benefit analysis. 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