Early ocular hypertension after cataract extraction.

Abstract

This study describes a dramatic rise in intraocular pressure which occurs within a few hours after cataract surgery without the use of a-chymotrypsin. Early reports stated that intraocular pressures remained low after cataract surgery, but these statements were based on measurements made several days (Hilding, I955) or weeks after surgery (Miller, Keskey, and Becker, 1957). Applanation measurements made I2 hours after surgery were reported at or below the preoperative level (Galin, Baras, and Perry, I96I). Gormaz (i962, 1973) first reported ocular hypertension one day after cataract surgery and did not use oc-chymotrypsin. Giardini and Paliaga (I964) reported ocular hypertension 8 hours after cataract surgery with a technique which included the use of oc-chymotrypsin. The association of this enzyme with a postoperative rise in intraocular pressure was made by Kirsch (I964). Galin, Barasch, and Harris (I966) supported this relationship. However, in those eyes in which o-chymotrypsin had not been used, Kirsch (I964) reported a 23 per cent. and Galin and others (I966) an 8 per cent. incidence of ocular hypertension, by their criteria. Rich ( I 968) demonstrated a consistent rise in intraocular pressure one day after cataract surgery without the use of a-chymotrypsin and with a technique designed to secure water-tight incision closure. He suggested that an early postoperative rise in intraocular pressure followed all cases of cataract surgery in which incision closure was water-tight. MethodsCataract surgery was performed on ten consecutive patients (Cases i to I o) whose eyes were otherwise normal. The age range was 54 to 86 yrs. Preoperative preparation of the patient included one drop of a steroid-antibiotic combination the night before and on the morning of surgery. Preoperative sedation was intramuscular diazepam IO mg. one hour before surgery. No mydriatic or other medication, local or systemic, was used. The operations were performed under local anaesthesia with topical proparacaine o-s per cent. and facial nerve block and retrobulbar anaesthesia with lignocaine 2 per cent. with adrenaline i :iooo and hyaluronidase. The operations were performed by the same surgeon using a surgical microscope.The anterior chamber was entered beneath a limbus-based conjunctival flap through a bevelled comeo-scleral incision; the outer two-thirds of this incision were vertical and the inner portion sharply angled anteriorly. Two corneo-scleral sutures of 25 p diameter Perlon were placed before the chamber was entered. The lens was removed by cryoextraction. a-chymotrypsin was not used. The anterior chamber was then irrigated with a I in 200 solution of acetylcholine, the corneo-scleral sutures were tied, and a basal iridectomy was performed. The corneo-scleral incision was additionally

Effect of carbachol on intraocular pressure in small-incision cataract surgery

“…Rich and his co-workers [10] performed intraocular pressure measurements hourly following intracapsular cataract surgery and found the highest means 6 to 8 hours postoperatively. Usually intraocular pressure is measured at the first postoperative visit 24 hours postoperatively.…”

A comparative study of postoperative intraocular pressure changes in small incision vs conventional extracapsular cataract surgery

“…Eye Application of corneoscleral sutures causes a watertight wound closure, which contributes to more elevation of IOP. 6,8 In SICS, tunnel preparation is less traumatizing to trabeculum than a corneoscleral incision with subsequent suturing, which leads to more surgical inflammation that results in narrowing of filtration channels and reduced aqueous outflow. 8 Release of prostaglandins during intraocular surgery also causes disruption of blood aqueous barrier and subsequent rise in IOP.…”

“…There are numerous reports on effect of conventional cataract surgery on intraocular pressure, [3][4][5][6][7][8][9][10][11][12] but very few on small incision cataract surgery. 13 Initial rise of IOP in early postoperative period after cataract surgery is well documented.…”

Extraction, Purification and Characterization of Fish Chymotrypsin: A Review

“…Cataract extraction: Alpha chymotrypsin is widely used to separate cataractous lens from the zonular attachment sites (Hill, 1960;Rhee et al, 1999;Rich et al, 1974). Chymotrypsin decreases the manipulating force required during the surgery to make it easy to remove the cataract which guarantee a higher success rates in surgery (O'Malley and Straatsma, 1961).…”

“…Using α-chymotrypsin during the cataract surgery can help avoid significant intraocular pressure (IOP). Rapidly raised IOP may cause pain and comeal oedema to patients (Rich et al, 1974;Passo et al, 1985).…”