Conventional extracapsular cataract extraction and its importance in the present day ophthalmic practice

Abstract

Purpose:

A retrospective study aimed to evaluate high risk cases where conventional Extracapsular cataract extraction (ECCE) was performed, their intra-operative and post-operative outcomes.

Setting:

Sri Srinivasa Sankara Nethralaya (Tirupati) Tirumala Tirupati Devastanams Central Hospital, Tirupati, India.

Subjects and Methods:

Retrospective study of 207 patients who underwent ECCE at the hospital between august 2010 to June 2012. Operative data included details like grade of risk, intra and postoperative complications and visual outcome.

Results:

Out of 207 cases, 188 were in group 3 (moderate risk, 3-5 points) and 19 in group 4 (high risk, 6 points or more). The intra operative complications in group 3 were 8 (0.042%) and none in group 4. Final best corrected visual acuity (BCVA) of 6/12 and more were 184 (88.88%). Final refraction of less than 2.0 astigmatism was seen in 80.19% (n=166).

Conclusion:

Segregation of cases depending on the risk factors can lead to lower intra operative complications and therefore good postoperative outcome. We believe that phacoemulsification, manual small incision cataract surgery (MSICS) and ECCE each has its own importance and should be used as per the cataract with risk factors.

Introduction

Cataract is the single most important cause of avoidable blindness globally.[1] Extracapsular cataract extraction (ECCE) with posterior chamber intraocular lens implantation (PCIOL) was the most frequent surgical technique to treat cataracts until the past two decades.[2] Phacoemulsification and manual small incision cataract surgery (MSICS) are the predominant cataract surgeries being preferred to ECCE due to shorter surgical time, quicker rehabilitation, and reduced postoperative astigmatism.[3] However, in high-risk cataract cases both phacoemulsification and MSICS have been associated with greater intraoperative complications.[4]

To assess the risk of complications in individual patients preoperatively, Muhtaseb et al. have developed a system of patient classification which was further validated by Agrawal and Upadhyay.[4,5] However, there has been no study to our knowledge, where deliberate segregation of high-risk cataract cases for planned ECCE have been done and studied. We classified the patients with cataract who underwent ECCE into the different risk groups following the criteria of Muhtaseb et al. and assessed the results of our study.

Aim

Our retrospective study aimed to evaluate the results of ECCE in high and moderate risk cataracts their intraoperative, postoperative, and visual outcomes.

Materials and Methods

The electronic medical records of all the patients who underwent ECCE in our tertiary care ophthalmologic center from August 2010 to June 2012 were reviewed. All the surgeries were performed by two surgeons with an experience of more than 7 years in anterior segment surgery. Inclusion criteria were brunescent/black/total/white/dense cataract, pupil size <3 mm, pseudoexfoliation, and phacodonesis.

Exclusion criteria were known patient of glaucoma, unplanned ECCE, traumatic cataract, and posterior polar cataract.

The preoperative risk factors were broadly classified into three categories [Table 1]. Scoring points were allotted to each risk factor based on the severity of the risk factor. Each patient was further grouped into one of the four groups (mentioned below) based on a total number of points scored by each individual patient.

Table 1.

Patient characteristics used in the scoring protocol

Group 1 (no added risk) 0 points, Group 2 (low risk) 1–2 points, Group 3 (moderate risk) 3–5 points, Group 4 (high risk) 6 points or more (according to Agrawal et al. study).

No grading score for the history of complicated cataract surgery in the fellow eye was considered in this study.

Documentation of the variables included: Age, gender, cataract related symptoms, visual acuity as Snellen fraction values, and the incidence of co-existing vision-threatening ocular pathology. Operative data included details of intra- and post-operative complications and visual outcome. At 6 weeks follow-up uncorrected and best corrected visual acuity (BCVA), with any ocular complaint related to surgery, were documented.

Procedure

ECCE was performed under peribulbar anesthesia with 3–5 m of 2% xylocaine. The operating eye was prepared with povidone eye drops and swabs. After insertion of wire speculum, a 4–0 silk suture was placed in superior rectus muscle tendon for traction. A superior limbal peritomy was performed. The scleral bed was cauterized. A no. 15 blade was used to make a groove at the limbus from 10 to 2’o clock. A stab entry was made with a razor blade. Dispersive hydroxyl propyl methylcellulose viscoelastic (APPAVISC) was then injected, and large can opener capsulotomy was made. The incision was then extended with corneal scissors. Hydrodissection was done at 3, 6, and 9 o’clock position. The nucleus was expressed out using pressure and counter pressure method.

In small pupils (<3 mm), the pupil was first viscodilated, and a canopener capsulotomy was done within the margins of the pupil. Sphincterotomies were avoided to preserve the contour of the pupil in order to accommodate, anterior chamber intraocular lens (ACIOL) if needed. Careful mini hydrodissection was performed in all quadrants. The nucleus was then guided out by pressure counter pressure method. The initial pressure was given at 6 o’ clock on the limbus with a muscle hook. Subsequently pressure was given at 12 o’ clock on the limbus with a bent pierce. These two steps opened up the incision. The nucleus was loosened from the bag; the pupil stretched and pressure counter pressure was then continued with muscle hook slowly advancing over the cornea superiorly. Once a major part of the nucleus was out of the section it was hooked out, and the anterior chamber immediately reformed with balanced salt solution (Alcon BSS).

In cases of phacodonesis with or without pseudoexfoliation, after capsulotomy, multiple quadrants hydrodissection was done. Viscoelastic was injected at 12 o’ clock position below the nucleus and with the same cannula the nucleus was lifted up. Slight pressure was given at the section with the cannula, and the nucleus was guided out past the pupil through the section. The larger section allowed the nucleus to be removed in a much more controlled manner.

A holding suture (10–0 silk suture was taken one on each side 2 mm from the end. Co-axial irrigation and aspiration of the residual cortex were done using Simcoe's cannula. The anterior chamber was formed by viscoelastic (dispersive methyl cellulose). A rigid single piece polymethyl metha acrylate intraocular lens ((PMMA IOL, APPALENS, ultraviolet absorbing) was placed in the sulcus. Two more interrupted sutures were then taken, and a peripheral iridectomy was done. A final interrupted suture was then placed. The viscoelastic was then cleared out by irrigating saline (Alcon BSS). All suturing were done under viscoelastic cover. Wound integrity was checked. The entire surgery was of approximately 10–12 min duration.

Patients were examined day 1, day 7, and 6 weeks postoperatively. Postoperative cases with the high cylinder (>3.5 cylinder) were again reviewed after 1-month. In case of persistent astigmatism, selective suture removal was done.

Results

We analyzed 207 eyes included in our study, of which 188 eyes belonged to group 3 (moderate risk, 3–5 points) and 19 belonged to group 4 (high risk, 6 points or more) [Table 2]. There were none in group 1 and group 2. The demographics including the independent risk factors are shown in Table 3.

Table 2.

Grouping of patients based on risk factors

Table 3.

Demographics, cataract type and pre-operative visual acuity

Complications

There were six cases of posterior capsule rupture with the vitreous loss. In all cases, PCIOL was placed in the sulcus. In one case, whole bag removal occurred without any vitreous loss. ACIOL was placed in this case.

One case of iris prolapse was seen in the 1^st week of postoperative evaluation. Iris abscission with re-suturing was done. Selective suture removal was performed in 17 patients with high >3.5 postoperative astigmatism (8.21%).

Postoperative significant retinal findings included cystoid macular edema seen in four cases (1.93%). All the patients responded well to topical nonsteroidal anti-inflammatory drugs [Table 4].

Table 4.

Postoperative retinal findings

Final BCVA of 6/12 and more were seen in 184 cases [Table 5].

Table 5.

Visual outcome

The amount of refractive cylinder at final refraction is shown in Table 6.

Table 6.

Postoperative astigmatism

About 80.19% of cases had <2.0 D astigmatism in final refraction.

Discussion

ECCE is a time-tested surgery which has lost its prominence due to longer surgical time, longer rehabilitation and increased postoperative astigmatism. Phacoemulsification and MSICS though with obvious advantages have to be performed with increased caution in some high-risk cases. Further in our institute where a surgical vitreoretinal setup is not available, a dropped nucleus is considered catastrophic. Prolapsing the nucleus into the anterior chamber is an important step in MSICS. Complications like zonular dialysis occur during this step in small pupil (<3 mm) with hard cataract. In conditions of weak zonules like pseudoexfoliation, hypermature cataract and mild phacodonesis MSICS may not be totally safe. Further, hypermature cataract and black cataract have thin posterior capsules. Though small incision cataract surgery has been performed in mature and black cataract. Gogate et al. observed that in these cataracts ECCE may be a safer option.[6,7] A smaller section of MSICS is also responsible for postoperative corneal edema, sometimes leading to bullous keratopathy.[8] With the larger section of ECCE, delivery of nucleus can be performed in a more controlled manner without any damage to the corneal endothelium.

Agrawal et al. observed that more the risk factors, higher the intraoperative complications seen during phacoemulsification. In their study, intraoperative complications were 10.66% and 32.24% in Group 3 and Group 4, respectively. Complications such as posterior capsule rupture, zonular dehiscence, nucleus drop, corneal burns increased in the higher risk groups. Moreover, they opined that these cases be performed by the experienced surgeons and be avoided by the trainee surgeons. Advanced cataract[11] and pseudoexfoliation[12] have shown to cause a higher rate of posterior capsular rupture and vitreous loss following phacoemulsification.[9,10] In a similar type of high-risk cataract cases, taking safety factor into consideration, we performed ECCE with much lower intraoperative complications. In our study, group 3 had 7 (0.042%), and group 4 had nil complications. Although, we do not conclude that ECCE is the procedure of choice in these cases, our study shows that ECCE performed in such a scenario can give a good outcome.

Nil complication in group 4 may have been due to the low sample size. However, Mujaini et al. showed that ECCE in patients with advanced cataract and pseudoexfoliation was quite safe with nil complications.[11] However, a large, comparative study is needed to confirm the results.

The most common postoperative complication seen in our study was tight sutures requiring suture removal in 17 eyes (8.1%). Of them, 12 eyes had a final astigmatism of <2 diopters. In Minassian study 37% required suture removal.[12] In the present study, 80.19% patients had <2.0 diopter astigmatism. In Gurung study 26%, and in Guzek study 62.5% patients had <2.0 diopter astigmatism.[13] In ECCE, postoperative high astigmatism has been an issue in various studies. In our study, the astigmatism was reduced intraoperatively by avoiding excessive tightness or looseness while locking the sutures. Suturing was always done under viscoelastic cover, and all surgeries were done by experienced surgeons. In our opinion, meticulous suturing can reduce postoperative astigmatism thereby reducing the need for suture removal. Patients having BCVA of >6/12 in our study were 184 (88.88%). This was similar to Gogate study 86.7% and better than Gurung et al. study 72%. In our study, a higher BCVA may have been due to the lower postoperative astigmatism.

Conclusions

In a set up where management facilities for complications associated with high-risk cataract are inadequate, performing an ECCE by a trained surgeon is still a safer option.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.