|Year : 2020 | Volume
| Issue : 1 | Page : 18
Phacoemulsification: A trainee's perspective
Simanta Khadka1, Purushottam Joshi2, Prava Subedi2, Chandni Pradhan2
1 Department of Vitreo-Retina, Bharatpur Eye Hospital, Chitwan, Nepal
2 Department of General Ophthalmology, Mechi Eye Hospital, Jhapa, Nepal
|Date of Submission||24-Apr-2020|
|Date of Acceptance||07-May-2020|
|Date of Web Publication||24-Jul-2020|
Dr. Simanta Khadka
Department of Vitreo-Retina, Bharatpur Eye Hospital, Chitwan, Bharatpur-10
Source of Support: None, Conflict of Interest: None
Background: Phacoemulsification is the main stay of cataract extraction surgery in the developed world as well as it is becoming increasingly popular in the developing nations as well. However, this technique is not widely incorporated in the residency training program in many developing nations.
Objective: This study was conducted to evaluate the visual outcomes and complications of phacoemulsification surgery performed by a trainee surgeon.
Methods: A prospective, cross-sectional study was performed in the tertiary eye hospital of eastern Nepal. All the consecutive cases of phacoemulsification surgery were included which was performed by a trainee surgeon with previous exposure of conventional extra-capsular cataract surgery and competency in sutureless manual small incision cataract surgery. The technique implied for nuclear division was stop and chop method. The visual outcomes and the complications of the surgery were evaluated.
Results: A total of 200 eyes of 200 patients were included. The patients were followed up for 12 weeks. The mean age of the patients was 57.8 ± 9.8 years. The average effective phacoemulsification time (EPT) was 21.6 ± 15.8 seconds. The incidence of intra-operative complication of posterior capsular rupture with vitreous loss was 6/200 (3%). Striate keratopathy was present in (6.5%) of the cases in the first post-operative day. At the final examination, improvement in vision by 6/12 or better was observed in 183 (91.5%) eyes.
Conclusion: Improvement in surgical teachings, good orientation to manual cataract extraction, careful selection of early cases and staffed supervision will lead to safe and easy transition to phacoemulsification surgery.
Keywords: Complications, manual sutureless small-incision cataract surgery, phacoemulsification, trainee, visual outcomes
|How to cite this article:|
Khadka S, Joshi P, Subedi P, Pradhan C. Phacoemulsification: A trainee's perspective. Pan Am J Ophthalmol 2020;2:18
| Introduction|| |
Cataract surgery is one of the most commonly performed intraocular surgical procedures in the world. Phacoemulsification is the mainstay of cataract extraction in the developed world., It is also increasingly becoming the standard way by which cataracts are operated in developing countries.
Over the past decades, extracapsular cataract extraction (ECCE) has become a more commonly performed procedure than intracapsular cataract extraction, which is almost obsolete in Nepal. Conventional large incision ECCE with nonfoldable posterior chamber intraocular lens (PCIOL) implantation was the initial surgical technique taught to the trainee ophthalmologist. This technique is still incorporated into few residency programs in Nepal. The trend has now changed toward the preference for smaller incisions and sutureless surgeries for cataract extraction. Majority of the trainees, especially in developing countries, learn the manual sutureless small-incision cataract surgery (MSICS) technique initially followed by phacoemulsification. The advances in phacoemulsification technique have brought cataract surgery results near to anatomical perfection as possible. However, implementation of phacoemulsification is limited by the start-up and training cost.
The popularity of phacoemulsification has become evident in our country over the past several years. Training programs in developed nations have already started teaching phacoemulsification as the basic technique of cataract removal. Sooner or later, this technique will be integrated in residency training programs as well. The learning curve of phacoemulsification is quite unrelated to other techniques of cataract surgery which is evident from the experience of cataract surgeons making this transition. The majority of available reports were from the experience of a skilled surgeon. However, experience of a trainee surgeon is lacking in our part of nation. Hence, this study was conducted to evaluate the visual outcomes and complications of phacoemulsification surgery performed by a trainee surgeon.
| Materials and Methods|| |
This study prospectively analyzed consecutive cases of phacoemulsification with PCIOL implantation performed by a single trainee (SK) at Mechi Eye Hospital (MEH), Birtamode-9, Jhapa, over a period of 6 months. MEH is one of the pioneer eye hospitals in Eastern Nepal which serves not only the people of Nepal but also caters to the peoples from neighboring countries such as India, Bhutan, and Bangladesh. A trainee surgeon is defined as someone who has completed his/her ophthalmology residency training and has joined for anterior segment fellowship program at this institute. Permission for this study was obtained from the local ethical committee of MEH and adhered to the tenets of the Declaration of Helsinki. The trainee had an exposure of conventional ECCE during his residency and had independently performed more than 2500 MSICS in MEH and can handle the anterior segment complications of MSICS. Before beginning phacoemulsification surgery, the trainee attended lectures on phacoemulsification, regularly interacted with the mentors, quarterly reviewed own surgical performance, and spent 12 months of training in MSICS surgical techniques during the 1st year of fellowship. A trainee was deemed suitable to proceed with phacoemulsification after review of results of the performed MSICS. First few cases of phacoemulsification were supervised by anterior segment surgeon with extensive experience in phacoemulsification surgery. All the consecutive cases of phacoemulsification done by the trainee were included. However, MSICS performed by the trainee during the same period was excluded. A careful selection of cases were supervised by the mentors during this period which excluded one eyed patient, non-dilating pupil, subluxated lens, complicated cataract, mature cataract, and previous history of complications during cataract surgery in the fellow eye.
Preoperative examination of the elective eye was performed. The data collection for each eye was done which included the patient's age and gender, preoperative visual acuity (VA) (uncorrected VA and best-corrected VA [UCVA and BCVA], respectively), and details of slit-lamp biomicroscope examination. The posterior pole was examined with slit-lamp biomicroscopy using +90 D lens. Indirect ophthalmoscopy was done to evaluate the details of retinal periphery. The status of the fellow eye was similarly documented. The intraocular pressure was recorded by applanation tonometry in all cases. In the case of nonvisibility of posterior segment, B-scan ultrasonography was performed. Axial length measurements and keratometry recordings were done, and SRK-II formula was applied to calculate the required PCIOL power. The general systemic status of the patient was evaluated to ensure fitness for surgery under local anesthesia.
Operative data included the name of the surgeon, date of the surgery, details of surgical procedure, effective phacoemulsification time (EPT), and details of the intraocular lens (IOL) implanted. The occurrence of any intraoperative complication was documented along with the details of the subsequent management.
Peribulbar block was given in all cases. The anesthetic agent used was 2% xylocaine with adrenaline (1:10,000) to which hyaluronidase was added. Manual compression was used to reduce the intraocular pressure. The details of operative procedure in succession were as follows. After antiseptic painting and draping, universal eye speculum was applied. Self-sealing corneal incision was made with 3.2 mm keratome at 10 o'clock position. Air was injected into the anterior chamber (AC) followed by trypan blue 0.6% to stain the capsule. The dye was washed and ophthalmic viscoelastic was injected to maintain the AC. Continuous curvilinear capsulorrhexis was initiated with cystitome and completed subsequently, or Utrata capsulorrhexis was used when necessary. After completion of capsulorrhexis, a second paracentesis wound was created at 2 o'clock position with 15° super blade. The phacoemulsification machine used was peristaltic pump-based Catarhex 3 (Oertli, Switzerland) in all cases, and the machine parameters used were power 35%, aspiration 35 ml/min, and vacuum 350 mmHg. The first technique that was taught to the trainee for nucleofraction was stop-and-chop technique. In this technique, initial groove or trench at about 2/3rd depth of the nucleus was made with the tip of phaco handpiece and propagated along the groove after rotation of nucleus by 180°. The nucleus was then divided by the use of two instruments, namely Nagahara chopper and Sinskey hook inserted from the constructed wound. The nucleus was emulsified by the phaco handpiece and use of Nagahara chopper in the nondominant hand by piecemeal. After complete removal of the lens nucleus, the remaining cortical matter was cleaned by coaxial irrigation aspiration (I/A) probe. Single-piece foldable PCIOL was injected from the main port through injector and positioned in the capsular bag. The viscoelastics were washed subsequently with I/A probe, and corneal wound hydration was done. AC was maintained throughout the procedure. The surgery was concluded with subconjunctival injection of gentamicin (20 mg) and dexamethasone (2 mg) and eye padded after application of 1% chloramphenicol, 0.1% polymyxin B, and dexamethasone ointment (Ocupol-D®, Centaur Pharmaceuticals, Mumbai).
The initial surgeries were supervised by an experienced phacoemulsification surgeon; all surgeries were approached with a mindset of “bailout,” with conversion to either MSICS or conventional ECCE. Intraoperative complication of posterior capsular rent (PCR) was managed by performing mechanized vitrectomy using the vitreous cutter provided with Catarhex 3 (Oertli, Switzerland) at the cut rate of 1200 cpm with an attempt to preserve as much anterior and posterior capsule as possible for supporting a PCIOL. All patients with vitreous loss underwent a meticulous mechanized vitrectomy and the use of triamcinolone acetonide to help identify the vitreous and ensure the absence of vitreous incarceration in the wound or any residual vitreous in the AC. In the event of complications or impending complications, the mentors guided the trainees and helped in averting the complication or in managing the problem when needed.
The postoperative examinations also followed a standard protocol. Postoperative data were documented on the first day, between 4 and 5 weeks, and finally, at 12-week visit. Starting from the first postoperative day, topical prednisolone acetate 1% eye drops six times per day and topical ofloxacin 0.3% eye drops six times per day were given for the 1st week. From the 2nd week onward, topical steroids were tapered on a weekly basis and antibiotic drops were continued for four times a day over the next 5 weeks. On each of follow-up visits, UCVA and pinhole improvement were noted. Details of slit-lamp examination of the anterior and posterior segment were noted, and any postoperative complications were recorded. On the last follow-up visit, in addition to the above, refraction was performed by an experienced optometrist and BCVA was noted, and glasses were prescribed.
For statistical purpose, VA was measured using the Snellen chart and converted to logarithm of the minimum angle of resolution (logMAR) equivalent for analysis. A modified scale was used to assign nonnumerical visual acuities to logMAR scores of 2.0, 2.7, 3.0 and 4.0 “counting fingers, ”“hand movements, ”“perception of light, ”and “no perception of light, ”respectively. Data were processed and analyzed using SPSS 20 (IBM SPSS Statistics for Windows, Version 20.0; IBM Corp, Armonk, New York, USA). Frequencies and percentages were computed to describe categorical data. Linear regression is used to study the linear relationship between visual outcome and independent variables such as age and effective phaco time. A paired t-test was used to compare mean preoperative and postoperative VA. P < 0.05 was considered statistically significant.
| Results|| |
A total of 200 eyes of 200 patients (male: 107 and female: 93) who underwent phacoemulsification surgery performed by a single trainee surgeon during a period of 6 months were included. Among the 200 eyes, right eye surgery was done in 94 and left eye surgery was done in 106 patients, respectively. The patient and case parameters are shown in [Table 1].
The most commonly encountered intraoperative complication was PCR 6/200 (3%). In all the cases with PCR, meticulous vitreous management was done and we were able to implant PCIOL in sulcus in three cases and in-the-bag placement of PCIOL was possible in two cases. However, due to inadequate capsular support, one case had to be turned to MSICS to implant a Kelman open-loop AC IOL. During PCR and vitreous loss, supervisors were called in for management of the case. All cases of PCR occurred during the step of nucleofraction. Striate keratopathy 13/200 (6.5%) was frequent postoperative complication on the 1st day following surgery. At the final follow-up, posterior capsular opacification (PCO) was present in 10/200 (5%) patients [Table 2]. The eyes with PCO underwent capsulotomy by neodymium: yttrium-aluminum garnet (Nd:YAG) laser.
The patients were followed up at 4–5 weeks postsurgery and for the period of 12 weeks at the conclusion. The BCVA was included at the last visit, and it was found better than the preoperative vision which is statistically significant [Table 3]. A comparison of the VA revealed that 169/200 (84.5%) had VA <6/60 before the surgery and 183/200 (91.5%) regained BCVA of 6/12 or better after the surgery [Figure 1]. A single patient who had post-operative VA <6/60 was found to have age related macular degeneration.
|Figure 1: Comparison of preoperative and postoperative best-corrected visual acuity after phacoemulsification surgery|
Click here to view
| Discussion|| |
The popularity of phacoemulsification also raises the issue of the morbidity involved in learning this technique. To the best of our knowledge, experience of a phacoemulsification surgery by a trainee who is still in the phase of surgical training is not available in our country. Although residency program in the Western world has accepted and incorporated training in phacoemulsification, the residency training in our country is not able to provide sufficient exposure to this technique. Hence, at present, we are obliged to go beyond residency to get oriented with the phacoemulsification surgery.
The visual outcomes of phacoemulsification performed by a trainee surgeon in our study were comparable with other studies.,, We were able to include the visual outcomes of the patient only up to 12 weeks. The longer followup was not possible because the major cause for the dropout rate is due to the service seeker's geographical location. The majority of patients visiting our facility belong to various parts of the neighboring countries. In addition, this leads to another speculation that the patients who achieved better working vision also lost the follow-up after surgery.
The learning curve is generally accepted to be quite steep for phacoemulsification cataract surgery., However, there is also denial for this ideology. With improvements in surgical teaching and adequate exposure in residency training, will probably lead to safe transition to phacoemulsification cataract surgeries. However, there is a common consensus about a greater risk in phacoemulsification done by beginners in complicated cases (i.e. hard nucleus; poor dilation; previous miotic glaucoma therapy, laser iridotomies, or synechias with filtering procedures; and shallow AC). The lesser incidence of complications in our study might be due to careful selection of cases and surgeon's previous experience with MSICS.
Our study did not divulge any significant influence of age in the final visual outcome. Various studies had revealed that cataract surgery among the elderly also resulted in significant improvement in vision. Nonetheless, the age factor along with pre-existing ocular conditions affects the final outcome. The EPT averaged at 21.6 ± 15.8 s (2–98 s) in our series, whereas it ranged from 7.92 ± 4.97 s for softer nucleus and 15.75 ± 9.45 s for moderate-to-hard nucleus. The phacoemulsification (phaco) time is also found to vary with the surgeon's level of expertise in managing nucleus as well as the technique implied in nuclear fragmentation. Stop-and-chop technique is found to have lesser phaco time compared to divide and conquer. However, Nagahara phaco chop is advocated to be more power efficient in terms of phaco time and power. Divide and conquer technique is taught to trainees in India, but our institution has applied stop-and-chop technique as the primary nuclear fragmentation technique. Vitreous loss following PCR is one of the most common and potentially serious intraoperative complications of cataract surgery. The rate of PCR and vitreous loss in our study was 6/200 (3%). The intraoperative complication rate was comparable to the beginner performing phacoemulsification under supervision. The incidence of PCR also varies upon the expertise of the surgeon, where it is reported as less as 1.3% among the experienced surgeon. Nonetheless, the incidence of PCR and vitreous loss was comparatively higher among the novice where it ranges from 5.5% to 14.7%. The incidence of this complication tends to decline with experience and the number of cases performed. Similarly, the tendency of beginners to prolapse the nucleus into AC compared to in the bag nuclear division also may lead to higher chance of PCR. The lower incidence of PCR in our study is attributed to careful selection of cases and close supervision of surgery. Additionally, the trainees undergoing longterm training programs are initially taught MSICS technique followed later by supervised phacoemulsification surgery that would have resulted in lower PCR rates. This could ultimately translate into a better surgical hand and improved tissue handling intraoperatively. Iris-related complication in our study can be ascribed to a surgeon's handling of secondary instrument and inadvertent iris manipulation.
Density of the nucleus, higher phaco power time, type of viscoelastics, and application of phacoemulsification tip in AC might have led to striate keratopathy postoperatively. Although these changes are temporary, amendment of these factors could lead to better immediate postoperative visual recovery. The PCO encountered (5%) during 12-week follow-up in our series were successfully managed by Nd: YAG capsulotomy. The relatively limited follow-up precludes the evaluation of long-term problems such as retinal detachment and the ultimate success of the surgical procedure.
A controversy exists over whether a trainee surgeon should begin by learning ECCE or MSICS first and then convert to phacoemulsification. There is a division in opinions where there are supporters for phacoemulsification as a primary teaching technique for trainees,, whereas some support that the idea of previous learning from manual cataract surgery would yield comparable visual outcomes and easy transition to phacoemulsification. We believe that improvement in surgical teachings, good orientation to manual cataract extraction or phacoemulsification whether be in residency training or after a brief fellowship program, careful selection of early cases, and staffed supervision will lead to safe phacoemulsification from the onset and yield excellent results.
Our study is not immune to limitations. Limited number of cases, single center, surgeries performed by a single trainee surgeon, outcomes not compared with other surgeons, and short follow-up duration are the shortcomings. However, despite the above mentioned limitations, we are certain that the result of this study can be extrapolated to other residency or training programs where phacoemulsification surgery is not routinely taught.
| Conclusion|| |
The majority of available reports were from the experience of a skilled surgeon. However, experience of a trainee surgeon is lacking in our part of nation. Hence, this study was conducted to evaluate the visual outcomes and complications of phacoemulsification surgery performed by a trainee surgeon.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3]