Research Article
Study of Visual Outcome after Neodymium YAG Laser Therapy in Posterior Capsular Opacity
Pawan N Jarwal*
Corresponding Author: Pawan N Jarwal, Senior resident, A-123, JDA Colony Paldi Meena Agra road, Jaipur, Rajasthan, India
Received: April 25, 2020; Revised: September 15, 2020; Accepted: September 13, 2020 Available Online: November 04, 2020
Citation: Jarwal PN. (2020) Study of Visual Outcome after Neodymium YAG Laser Therapy in Posterior Capsular Opacity. Ophthalmol Clin Res, 3(3): 173-176.
Copyrights: ©2020 Jarwal PN. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Share :
  • 2520

    Views & Citations
  • 1520

    Likes & Shares
Purpose: Posterior capsular opacification is the most common long-term complication of modern IOL surgery. Neodymium YAG laser remains the cornerstone of its treatment. In this study, an attempt was made to study the visual outcome following Neodymium YAG laser capsulotomy.

Methods: This was a prospective study of 50 patients conducted in Jaipuriya Hospital, attached to RUHS-CMS Medical College, Jaipur. All patients aged 50 years and above, attending the regular OPD who presented with visually significant posterior capsular opacification were treated with Neodymium YAG laser capsulotomy. After capsulotomy, follow up was done 1 – 4 h after Capsulotomy, day one, end of first week, end of first month and at the end of minimum 3 months. During follow-up the visual acuity Intra Ocular Pressure (IOP) and other relevant tests were conducted and appropriate intervention were made during the follow-up period.

Results: In my study duration of onset of symptoms of Posterior capsular opacity (PCO) is more between 2-3 years period after surgery. Pearls type of is Posterior capsular opacity more when compared to fibrous type. Most of the patients treated for Posterior capsular opacity with Neodymium: YAG laser capsulotomy showed an improvement in visual acuity. There was no incidence of major complications in patients treated with procedure.
Conclusion: Neodymium-YAG laser therapy presents the advantage of a non-invasive, effective, relatively safe technique to manage intact posterior capsule that opacity post operatively.
 
Keywords: YAG Laser, PCO, After cataract, IOL

Abbreviations: Nd-YAG: Neodymium Yttrium Aluminium Garnet; PCO: Posterior Capsule Opacity; PCIOL: Posterior Chamber Intra Ocular Lens; Nm: Nanometre; ECCE: Extra Capsule Cataract Extraction; IOL: Intraocular lens; SCI: Sealed Capsular Infusion; LECs: Lens Epithelial Cells; CCC: Continuous Curvilinear Capsulorhexis; mj: Milli joule; h: Hour; d: Day; Wk: Week; Mo: Month; nsec: Nanosecond; mm: Millimetre; IOP: Intra Ocular Pressure; RD: Retinal Detachment; CME: Cystoid Macular Edema; PMMA: Polymethyl Methacrylate; ACO: Anterior Capsule Opacity.
INTRODUCTION

The most common late post-operative complication of cataract extraction is with Posterior Chamber Intra ocular lens (PCIOL) is posterior capsular opacification. It causes the deterioration of visual acuity, however there is no effective method to prevent it. Nd-YAG laser capsulotomy is the procedure of choice.           
                  
Posterior capsular opacification is the most common long-term complication of modern Intra Ocular Lens (IOL) surgery. It occurs frequently in patients after cataract surgery, especially senile cataracts [1].

Many methods have been employed to reduce the incidence of PCO but none of these seems to be very effective on long term follow ups. Hence it has to be treated. Initially PCO used to be removed surgically but now, Nd: YAG laser is most commonly used as the best mode of treatment [2].

The advantage of Nd: YAG is that it’s non-invasive, of short duration, very effective and relatively safe technique, to manage intact posterior capsule that opacifies post operatively [3].
In this study, I have undertaken a hospital based prospective study of visual outcome after Nd-YAG laser therapy in posterior capsular opacity after subjecting them to detailed eye examination. We study the outcome of Nd: YAG laser posterior capsulotomy in patients who have developed PCO post operatively, in terms of the best corrected visual acuity (BCVA) and the intra ocular pressure (IOP).

OBJECTIVES
In my study patients in the age group of 50 year and above, attending RDBP Jaipuriya Hospital are diagnosed by subjecting them to detailed eye examination with the objective to study of visual outcome after Nd-YAG laser therapy in posterior capsular opacity in our setup [4].

METHODOLOGY
  1. Source of data
Patients attending outpatient department Jaipuriya Hospital, Jaipur during November, 2017 to July, 2018.  Ethical clearance taken from the review board.
  1. Methods of collection of data
It is a hospital based prospective study of 50 eyes of 50 patients on outpatient basis who underwent cataract extraction in our hospital diagnosed PCO by red reflex evaluation by retinoscopy, slit lamp examination, direct and indirect ophthalmoscopy, when indicated after informed consent the patient undergoes Nd-YAG capsulotomy [5]. Repeated capsulotomy if needed will be done. In those patients undergo capsulotomy standard examination will include visual acuity, anterior segment examination, slit lamp examination, intra ocular pressure recording and other relevant examination. The selection was made among the patient attending ophthalmology OPD on the basis of following criteria.

Inclusion criteria
All the patients with PCO diagnosed clinically.

Exclusion criteria
  1. Patient with significant media opacities – corneal opacity etc.
  2. Patient unable or unwilling to fixate adequately for the procedure.
 
Fifty PCO patients were selected on first come first basis from November, 2017 to July, 2018. The case notes of all PCO patients were recorded and their addresses were taken on the day of selection. Patient were briefly explained about the study and the tests they had to undergo. They were also told that they will be informed about the day they have to come to undergo the various tests.
Out of 72 patients informed, 50 patients turned up on the informed day whereas 22 patients did not turn up.
In a day about 2-3 patients / day were subjected detailed eye examination in the Jaipuriya Hospital, Jaipur.

The examination included
  1. Visual acuity testing
  2. Intraocular tension recording with schiotz / applanation / non-contact tonometer.
  3. Slit lamp bio microscopy
  4. Indirect / direct ophthalmoscopy
  5. Retinoscopy
After diagnosing PCO patients were subjected to Nd- YAG capsulotomy in the affected eye. After capsulotomy, follow up was done 1 – 4 hours after capsulotomy, day one, end of first week, end of first month and at the end of minimum 3 months. During follow-up the visual acuity IOP and other relevant tests were conducted and appropriate intervention were made during the follow-up period [6].

RESULTS

The study population comprise 50 patients (50 eyes) were diagnosed as PCO by red reflex evaluation by retinoscopy, slit lamp examination, direct and indirect ophthalmoscopy [7].

Then 50 confirmed cases of PCO were subjected to Nd-YAG capsulotomy the scheduled of post capsulotomy examination was 1-4 hour after capsulotomy day 1 end of first week, end of first month, and at the end of minimum 3 months.
Table 1 shows the male patients are more than female patients.
My study (Table 2) shows PCO is more in younger age group and decreased as age increases.

Table 3 shows left eye is more involved than the right eye in the study
Table 4 shows duration of onset of symptoms of PCO is more between 2-3 years period after surgery.
My study (Table 5) shows as in the above table pearls type of PCO is more when compared to fibrous type.

Table 6 shows symptoms of diminution of vision is more when compared to diminution of vision with glare.
Table 7. Showing the visual outcome after Nd-YAG capsulotomy.

In one case visual activity after capsulotomy deteriorated because of low tension glaucoma. In another case due to diabetic neuropathy of the optic nerve and another case due to myopic degeneration of the retina. Table 8 shows complication of Nd-YAG capsulotomy in my study group.
There was no incidence of major complications only 10 out of 50 patients had minor complications as shown in the table they were managed conservatively.
DISCUSSION

Nd-YAG laser therapy presents the advantage of a non-invasive, effective, relatively safe technique to manage intact posterior capsule that opacify post operatively [8]. It is evident that visual outcome after Nd-YAG in PCO in my study is 94%. The visual outcome of our patients has been compared with similar studies who have included 25 and 26 eyes respectively [5,9] (Table 9).

In one case visual acuity after capsulotomy deteriorates because of low tension glaucoma and in another case due to diabetic neuropathy of the optic nerve and one more case due to myopic degeneration of the retina.

I did not observe any serious complications following Nd-YAG laser capsulotomy displayed by others cystoid macular oedema, retinal detachment, iridocyclitis, except transient intraocular pressure elevation in 2 cases and intra ocular lens pitting in 8 cases. These were managed conservatively [10].

CONCLUSION

Hospital based prospective study of 50 eyes of 50 patients on outpatient basis who underwent extract capsular cataract extraction with PCIOL (PMMA) in our hospital are elsewhere diagnosed PCO by red reflex evaluation. When indicated after informed consent patient underwent Nd-YAG laser capsulotomy. These patients were followed up for minimum of three months. Visual acuity after capsulotomy with correction were recorded. In my study shows visual outcome after Nd-YAG laser capsulotomy is 94%. This study tallies with other two studies that shows 89 and 95% of the visual outcome [11].

I did not observe any serious complications following Nd-YAG laser capsulotomy displayed by others cystoid macular oedema, retinal detachment, iridocyclitis except transient intraocular pressure elevation in 2 cases and intra ocular lens pitting in 8 cases. These were managed conservatively [9].

The most common post-operative complications of cataract extraction is posterior capsular opacities. It causes the deterioration of visual acuity, the second most common cause of visual loss worldwide. PCO is a major problem in paediatric cataract surgery where the incidence approaches 100%. However, no effective methods to prevent it [12]. Nd-YAG laser therapy presented the advantage of a non-invasive, effective, relatively safe technique to manage intact posterior capsule that opacify post operatively and it does not require patient hospitalization [13-15].

LIMITATIONS OF THE STUDY
  1. A larger study is required with different types of IOL.
  2. Study requires, contrast sensitivity and glare testing to correlate with visual acuity.
 
REFERENCES
  1. Norman SJ, Marks SJ, Garry SJ (1997) Cataract surgery and its complications, 6th edition, pp: 409-410.
  2. Francis A, LES Perance (1989) J.R. Ophthalmic laser Vol. II, 3rd edition, The C.V. Mosby Co. Toronto, pp: 839-844.
  3. Cheng CY, Yen MY, Chen SJ, Kao SC, Hsu WM, et al. (2001) Visual acuity and contrast sensitivity in different types of posterior capsule opacification. J Cataract Refract Surg. 27: 1055-1060.
  4. Steinert RF (1995) Cataract surgery technique complications and management, United States of America, W. B. Saunders company, pp: 378-387.
  5. Polak M, Zarnowski T, Zagorski Z (2002) Results of Nd: YAG laser capsulotomy in posterior capsule opacification. Ann Univ Mariae Curie Sklodowska Med 57: 357-363.
  6. Hayashi K, Hayashi H, Nakao F, Hayashi F (2003) Correlation between posterior capsule opacification and visual function before and after Nd-YAG laser posterior capsulotomy. Am J Ophthalmol 136: 720-726.
  7. Meacock WR, Spalton DJ, Boyce J, Marschal J (2003) The effect of posterior capsule opacification on visual function. Invest Ophthalmol Vis Sci 44: 4665-4669.
  8. Keates RH, Stenurt RF, Puliafilo CA, Maxwell SK (1984) Long-term follow up of Nd-YAG laser posterior capsulotomy. J Am Intraocul Implant Soc 10: 164-168.
  9. Aslam TM, Patton N (2004) Methods of assessment of patients for Nd-YAG laser capsulotomy that correlate with final visual improvement. BMC Ophthalmol 204: 4-13.
  10. Stark WJ, Worthen D, Hollady JT, Murray G (1985) Nd-YAG laser An FDA report. Ophthalmology 92: 209-212.
  11. Pandey SK, David JA, Werner L, Maloof AJ, Milverton EJ (2004) Posterior capsule opacification: A review of the aetiopathogenesis, experimental and clinical studies and factors for prevention. Indian J Ophthalmol 52: 99-112.
  12. Wolff E, Bron AJ, Tripati CR, Tripati BJ (1997) Wolff’s Anatomy of the Eye and Orbit, 8th edition, Chapman & Hall Medical London, pp: 414- 416.
  13. Apple DJ (2000) Influence of intraocular lens material and design on post-operative intra capsular cellular reactivity. Trans Am Ophthalmol Soc 98: 257-283.
  14. Werner L, Apple DJ, Pandey SK (2000) Cataract surgery in complicated case. Thorofare, NI. Slack Line 2000, pp: 399-417.
  15. Peng Q, Hennig A, Vasavada AR, Apple DJ (1998) Posterior capsular plaque, a common feature of cataract surgery in the developing world. Am J Ophthalmol 125: 621-626.