|Year : 2013 | Volume
| Issue : 1 | Page : 7-8
Analysis of change in intraocular pressure after phacoemulsification
Kumar Sambhav, Ajita Sasidharan
Glaucoma Services, Sankara Eye Care Institutions, Sivanandapuram, Coimbatore, India
|Date of Web Publication||21-Sep-2013|
Sankara Eye Centre, Sathy Road, Sivanandapuram, Coimbatore
Source of Support: None, Conflict of Interest: None
Purpose: The purpose of this study is carried out to analyze the change in intraocular pressure after cataract surgery. Materials and Methods: We conducted a retrospective interventional case series of 218 patients, who underwent phacoemulsification surgery. Pre-operative and post-operative, intraocular pressure, and pachymetry were recorded. The change in intraocular pressure was recorded in both operated and fellow eyes and was compared using the statistical methods. Results: There was a mean reduction of 0.93 mm Hg in intraocular pressure in operated eye, which was statistically significant (P value 0.004). The change in fellow eye was 0.31 mm Hg, which was statistically insignificant (P value 0.16). Conclusion: This study proves the significant reduction in intraocular pressure after cataract surgery.
Keywords: Cataract surgery, intraocular pressure, phacoemulsification
|How to cite this article:|
Sambhav K, Sasidharan A. Analysis of change in intraocular pressure after phacoemulsification. Sudanese J Ophthalmol 2013;5:7-8
| Introduction|| |
Cataract and glaucoma are the leading causes of blindness worldwide.  Many patients with glaucoma have concurrent cataracts and some studies have suggested that cataract removal itself causes a reduction in intraocular pressure.
There is an increase in anterior chamber depth after cataract surgery because of the removal of bulky lens and implantation of thin intraocular lens. The increase in anterior chamber depth is suggested to cause an increase anterior chamber angle opening distance and an increase in aqueous outflow, which leads to reduction in intraocular pressure. This is especially helpful in cases with narrow angle glaucoma where cataract removal itself might lead to a decrease in intraocular pressure and a reduction in congestive attacks.
Many studies have demonstrated intraocular pressure reduction after cataract surgery. However, literature on using other eye as the control group is lacking. In this study, other eye has been taken as control; thus, eliminating the effect of diurnal variation and other contributing factors affecting the intraocular pressure.
| Materials and Methods|| |
This was a retrospective study conducted in a tertiary care eye care institution. Institutional Ethical Committee approval was taken. Computerized data of patients, who underwent uncomplicated phacoemulsification using the clear corneal incision, in the month of May and June 2012, were retrieved. None of the patient had glaucoma or other comorbid condition that might affect intraocular pressure. Data were collected, which include patient demography, pre-operative and post-operative visual acuity, pre-operative and post-operative intraocular pressure using the non-contact tonometer, pachymetry, pre-operative risk factors, systemic conditions and medications, and surgical complications. The follow-up was carried out at day 1, day 7, 1 month, 2 months, and 6 months. Final visual acuity and intraocular pressure was recorded at the end of 6 months. The difference between the pre-operative and post-operative intraocular pressure were compared in the operated eye (study group). The change in the intraocular pressure was also compared in fellow eye (control group).
| Results|| |
There were a total of 218 cases that met all criterions. There were 120 females and 98 males. The number of right and left eyes in study group was 128 and 90 respectively. In control group, the number of right and left eyes was 90 and 128 respectively. The mean age of the patients was 62.13 ± 11.00 years (13-86 years). The mean pachymetry was 498.93 ± 34.42 mm (419-615 mm) in study group and 495 ± 33.98 mm (405-621 mm) in control group (P value 0.42).
The pre-operative mean intraocular pressure in study group was 14.17 ± 3.47 mm Hg (5-24 mm Hg). There was a decline of 0.93 mm Hg in intraocular pressure at 6 months post-operative follow-up when the mean intraocular pressure was 13.24 ± 3.66 mm Hg (5-23 mm Hg, P value 0.004).
In control group, the baseline intraocular pressure was 13.97 ± 3.26 mm Hg (5-24 mm Hg), which at 6 months follow-up reduces by 0.31 mm Hg to a mean intraocular pressure of 13.66 ± 3.24 mm Hg (6-24 mm Hg, P value 0.16).
| Discussion|| |
The various studies of change in intraocular pressure after cataract surgery showed variable results with some confirming a reduction in intraocular pressure although other showing no improvement at all. However, these results vary because of differences in surgical technique.
The method of cataract extraction may influence the change in post-operative intraocular pressure. Phacoemulsification seems to lower intraocular pressure more than manual extra-capsular cataract extraction.  Furthermore, the clear corneal incision prevents distortion of anterior chamber angle architecture, which is especially important in cases with suspected glaucoma. Glaucoma itself is a risk factor for cataract development  and the presence of glaucoma may also influence change in intraocular pressure after phacoemulsification. Many factors such as surgical technique, intraoperative complication, post-operative medications, and type of viscoelastic contribute to short-term intraocular pressure fluctuations following surgery although the duration of post-operative medications affect the long-term change in intraocular pressure.  The reasons for decreased intraocular pressure after cataract surgery remain speculative, but there is a definite increase in the facility of outflow after cataract surgery.
Phacoemulsification is a very commonly performed surgery. Even though, cataract surgery alone lowers intraocular pressure, combining glaucoma with cataract surgery causes more lowering of intraocular pressure with fewer post-operative pressure spikes.  However, the complication and failure rate of glaucoma surgery leads to high morbidity. Hence, cataract surgery alone is an effective and safe way to lower intraocular pressure, especially in patients with early glaucoma.
| References|| |
|1.||West S. Epidemiology of cataract: Accomplishments over 25 years and future directions. Ophthalmic Epidemiol 2007;14:173-8. |
|2.||Suzuki R, Tanaka K, Sagara T, Fujiwara N. Reduction of intraocular pressure after phacoemulsification and aspiration with intraocular lens implantation. Ophthalmologica 1994;208:254-8. |
|3.||Ughade SN, Zodpey SP, Khanolkar VA. Risk factors for cataract: A case control study. Indian J Ophthalmol 1998;46:221-7. |
|4.||Arshinoff SA, Albiani DA, Taylor-Laporte J. Intraocular pressure after bilateral cataract surgery using Healon, Healon 5, and Healon GV. J Cataract Refract Surg 2002;28:617-25. |
|5.||Storr-Paulsen A, Pedersen JH, Laugesen C. A prospective study of combined phacoemulsification-trabeculectomy versus conventional phacoemulsification in cataract patients with coexisting open angle glaucoma. Acta Ophthalmol Scand 1998;76:696-9. |