Prospective comparison of the effects of Occucoat, Viscoat, and Healon on intraocular pressure and endothelial cell loss

We compared the effect of Occucoat (2% hydroxypropylmethyl-cellulose), Viscoat (sodium hyaluronate-chondroitin sulfate), and Healon (sodium hyaluronate) on postoperative intraocular pressure (IOP) and endothelial cell damage. One hundred fourteen patients having planned extracapsular cataract extraction with posterior chamber lens implantation using a viscomaterial were prospectively randomized into one of five groups. Group I received Occucoat which was removed from the anterior chamber at the conclusion of surgery. Group II received Occucoat which was not removed (retained). Group III received Viscoat which was removed, Group IV received Viscoat which was retained, and Group V received Healon which was removed. No prophylactic ocular hypotensive medications were given. Intraocular pressure was measured at four hours, 24 hours, one week, one month, three months, and one year postoperatively. Compared to preoperative IOP, all groups had a significant IOP increase at four hours. All but the Viscoat removed group (Group III) showed a statistically significant increase at 24 hours postoperatively (P less than .05). No group had a significant increase at one week or later. Specular microscopy showed no significant difference in cell loss between any of the groups at three months or within each group when compared to preoperative cell counts (P greater than .1).     

Protective effects of Healon and Occucoat against air bubble endothelial damage during ultrasonic agitation of the anterior chamber

An important aspect of any new viscoelastic substance is the corneal endothelial protection. We compared the protective effects of sodium hyaluronate (Healon) and hydroxypropylmethylcellulose (Occucoat) by introducing a controlled volume of air bubbles into the anterior chamber of human eye bank eyes during ultrasonic agitation of the anterior chamber. Eight eyes received Healon and 11 eyes received Occucoat. Damage to endothelial cells in the central cornea was quantified by vital staining. Endothelial damage averaged 4.5% in eyes in which no viscoelastic was used (positive control); damage was 0.4% in eyes in which a viscoelastic was injected but no air bubbles were introduced (negative control). We found that endothelial damage averaged 4.25% in specimens that received air plus Healon and 1.4% in specimens that received air plus Occucoat. Occucoat appeared to have somewhat better protective effects than Healon against air bubble damage to the corneal endothelium during ultrasonic agitation of the anterior chamber.     

Effects of Healon vs. Viscoat on endothelial cell count and morphology after phacoemulsification and posterior chamber lens implantation.

The endothelial cell count and several morphologic characteristics of the cells were examined before and after surgery in 56 consecutive patients (60 eyes) who underwent phacoemulsification and implantation of a posterior chamber intraocular lens with either Healon (30 eyes) or Viscoat (30 eyes) as the viscoelastic material. In all cases the technique was the same, including removal of the viscoelastic from the anterior chamber at the end of the operation. The mean cell loss was greater in the Viscoat group than in the Healon group (9.27% +/- 2.52% vs. 2.71% +/- 2.53%), but not significantly so. There was a significantly greater reduction in polymegathism in the Healon group than in the Viscoat group (p less than 0.05). Although the results suggest that Healon has a greater protective effect on the corneal endothelium than Viscoat, the greater effort needed to remove Viscoat from the anterior chamber may have adversely affected the endothelium. Further studies in which Viscoat is left in the eye are warranted.     

Removal of viscoelastic materials after experimental cataract surgery in vitro.

The one significant complication of viscoelastic materials is that they may cause postoperative intraocular pressure rise. We investigated the rate and ease of removal of various viscoelastics using the Miyake video technique. Five viscoelastics were investigated: sodium hyaluronate (Healon), Healon GV, chondroitin sulfatesodium hyaluronate (Viscoat), hydroxypropylmethylcellulose (Occucoat), and polyacrylamide (Orcolon). The viscoelastics were dyed with fluorescein and, after filling the capsular bag with a viscoelastic material, a posterior chamber intraocular lens (IOL) was implanted. The viscoelastic was then aspirated using an automated irrigation/aspiration device. Healon and Healon GV were completely removed within 20 to 25 seconds. Viscoat adhered to the lens capsule and to the posterior surface of the IOL and cooplete removal required approximately 3.5 minutes. Most Occucoat and Orcolon was aspirated within one minute; however, removal was completed only after three minutes. Removal of Healon and Healon GV was faster and more complete than removal of the other viscoelastics. Whether a small amount of viscoelastic left in the eye or trapped behind the IOL optic has any clinical significance has to be studied.     

Comparison of the effects of Viscoat and Healon on postoperative intraocular pressure

We compared the effects of Viscoat and Healon on postoperative increases in intraocular pressure in patients undergoing uncomplicated extracapsular cataract extraction with posterior chamber intraocular lens implantation in a prospective, randomized, single-masked study. Eleven eyes received Viscoat and 13 received Healon. The Viscoat or Healon was aspirated from the anterior chamber with the irrigation-aspiration tip of an automated irrigation-aspiration system at the end of the procedure. No prophylactic intraoperative or postoperative ocular hypotensive agents were used. Intraocular pressure was measured at three, six, 12, and 24 hours postoperatively. Compared with preoperative intraocular pressure, postoperative intraocular pressure was significantly increased in both the Viscoat group and the Healon group. Some postoperative intraocular pressures were as high as 50 to 60 mm Hg, despite removal of the viscoelastic substance at the end of surgery. There was no significant difference in the postoperative intraocular pressures of the Viscoat group and the Healon group.     

Secondary intraocular lens implantation in aphakia.

We retrospectively studied secondary intraocular lens (IOL) implantation in 165 aphakic patients (162 eyes) from May 1983 to August 1989. Seventy-five eyes (46.3%) had secondary IOL implantation; these included seven cases of trans-sulcus scleral fixation of the posterior chamber lens. The remaining 87 eyes could not have secondary IOL implantation because of the ocular conditions. The most common reason for secondary implantation was to relieve the discomfort caused by spectacles or contact lenses (56.2%). An anterior chamber lens was used in 43 eyes (57.3%) and a posterior chamber lens in 32 eyes (42.7%). Final postoperative visual acuity of 20/40 or better was achieved in 92.0% of the eyes with posterior chamber lenses, in 71.4% of the eyes with anterior chamber lenses, and in 57.1% of the eyes with scleral-fixated posterior chamber lenses. Endothelial cell loss was greater in the eyes with anterior chamber lenses than in the eyes with posterior chamber lenses. Of the cases that could be followed, 83.3% showed endothelial cell loss of less than 30% at six months postoperatively. Postoperative complications such as cystoid macular edema, persistent fibrinous membrane formation, and neovascular glaucoma occurred in only ten (13.3%) of the 75 eyes that had secondary implantation. These complications occurred more frequently in eyes that had anterior chamber lenses with anterior vitrectomy. There were no noticeable complications in the eyes that had trans-sulcus scleral fixation of posterior chamber lenses. Updrawn pupil, prolapsed vitreous, and peripheral anterior synechia were common conditions preventing secondary IOL implantation.     

The influence of the incision lenght on the early postoperative intraocular pressure following cataract surgery

In a prospective study we recorded the early postoperative intraocular pressure of 60 eyes following phacoemulsification and posterior chamber lens implantation. In 30 patients each the implantation either of a folded polyHema intraocular lens through a 3.5 mm incision or of a polymethylmetacrylate intraocular lens through a 7 mm incision was performed. Healon was used in all eyes and thoroughly evacuated from the capsular bag behind the implanted lens and the anterior chamber. For intraoperative miosis 0.5 ml acetylcholine chloride was injected into the anterior chamber after wound closure. Intraocular pressure was measured preoperatively as well as six hours, 18 hours, one week and two months postoperatively without the influence of antiglaucomatous medication. We found no statistically significant change of intraocular pressure at any measurement time in the 3.5 mm group (Student's t-test, p>0.1). In the 7 mm group only the rise of intraocular pressure at 18 hours was statistically significant (ps< 0.05, student's t-test). The comparison of the changes of intraocular pressure from preoperative values between both groups revealed a statistically significant difference at 18 hours (p<0.05, student's t-test) but not at any other time recorded. Intraocular pressure exceeding 22 mmHg was found at 6 hours in 4 (13.3%) patients of both groups and at 18 hours in 3 (10%) eyes of the 3.5 mm group and 5 (16%) eyes of the 7 mm group (p>0.1, Fisher's Exact Test). From these results we conclude that 1) regardless of the wound size the pressure rising effect of Healon is successfully counteracted by the aspiration technique described, and 2) with small-incision cataract surgery statistically significant less changes of intraocular pressure are observed in the early postoperative period.     

Empty-bag technique for acrylic intraocular lens implantation using Healon5

PURPOSE: To determine how often the empty-bag technique (EBT) for injecting an acrylic foldable intraocular lens (IOL) into the capsular bag using Healon5 (sodium hyaluronate 2.3%) will require a 2-compartment technique to remove the ophthalmic viscosurgical device (OVD) and compare this with that of a standard injection method using Healon5. SETTING: Cincinnati Eye Institute and Ambulatory Surgical Center, Cincinnati, Ohio, USA. METHODS: Forty-one eyes of 40 patients were randomly assigned to 1 of 2 groups. In Group A, standard capsular bag expansion was performed with Healon5 before implantation of an acrylic posterior chamber (PC) IOL. In Group B, Healon5 was placed in the anterior chamber followed by balanced salt solution expansion of the capsular bag before acrylic PC IOL implantation. In all patients, complete OVD removal was attempted with the automated aspiration tip anterior to the optic (rock 'n roll technique). The number of patients in each group who required placement of the aspiration tip posterior to the optic for complete removal was compared. Early postoperative intraocular pressure (IOP) was also compared. RESULTS: In Group A, 15 (75%) of 20 eyes required placement of the aspiration tip posterior to the optic for complete OVD removal and in Group B, 1 (0.05%) of 20 eyes. The postoperative IOP was similar in both groups. CONCLUSIONS: The EBT decreased the likelihood that a 2-compartment OVD removal method would be necessary when using Healon5 for acrylic PC IOL implantation. The limitations of this new technique must be fully understood before it is used.     

The influence of viscoelastic substances on the corneal endothelial cell population during cataract surgery: a prospective study of cohesive and dispersive viscoelastics

PURPOSE: To compare the ability of cohesive and dispersive ophthalmic viscoelastic devices (OVDs) to protect the corneal endothelium following in-the-bag phacoemulsification with implantation of a foldable posterior chamber intraocular lens (IOL). METHODS: In a prospective single-masked randomized study, 60 eyes of 60 cataract patients were assigned to three groups of 20 patients each, according to which OVD was used: Celoftal, Vitrax or Healon. The corneal response to surgery was evaluated by measuring the endothelial cell loss, the variation in mean cell area of the endothelial cells (CV), the frequency of hexagonal cells, and the central corneal thickness. Data were recorded preoperatively and 3 months postoperatively. RESULTS: Preoperatively, no significant difference was observed in cell count, CV, hexagonal pattern or pachymetry among groups. Postoperatively, all three groups had a significant decrease in cell count, but the decrease was significantly less in the Vitrax group (6.97%) than in the Celoftal (18.03%) and Healon groups (18.46%). No changes in CV, hexagonality or corneal thickness were observed within any of the three groups or among the groups. There was an equal and significant increase in visual acuity. CONCLUSIONS: Phacoemulsification with implantation of a posterior chamber lens is known to affect the density and morphology of corneal endothelial cells. Viscoelastics facilitate cataract surgery and protect the corneal endothelium during the procedure. Choosing a dispersive hyaluronate OVD during the phaco procedure may allow for protection of the endothelial cells while suppressing the formation of free radicals. This may be the reason for the superior protective effect on the corneal endothelial cells of Vitrax compared with Celoftal and Healon.     

The Clinical Study of Healon 5 in Phacoemulsification and IOL Implantation

Purpose: To compare a new ophthalmic viscoelastic device (OVD) Healon 5 with two other kinds of OVDs commonly used in China during phacoemulsification and intraocular lens (IOL) implantation in terms of removal time, intraocular pressure, corneal and anterior chamber response.Methods: This prospective randomized study, in which patients and observers are masked, comprises niety eyes. They were randomly divided into 3 groups with different OVDs. Healon 5 (sodium hyaluronate 5 000 2.3%) was compared with Healon GV (sodium hyaluronate 7 000 1.4%) and Iviz (sodium hyaluronate 1.0%) . The surgeries were performed with temporal corneal incision, phacoemulsification in situ and foldable lens intracapsular implantation. The characteristic and the removal time of the viscoelastic material as well as the postoperative IOP, corneal reaction and anterior chamber reactions of the eyes were observed preoperatively and 24 hrs postoperatively. Exclusion criteria were glaucoma, a preoperative dilated pupil diameter small     

Posterior chamber intraocular lens implantation in eyes with inactive and active proliferative diabetic retinopathy

We reviewed the records of 2,100 consecutive eyes that had undergone extracapsular cataract extraction with intraocular lens implantation between January 1981 and December 1989. Of these eyes, 21 had inactive and four had active proliferative diabetic retinopathy at the time of cataract extraction. Twenty-one eyes with inactive proliferative diabetic retinopathy received extracapsular cataract extraction with posterior chamber intraocular lens implantation, and four eyes with active proliferative diabetic retinopathy had both extracapsular cataract extraction with posterior chamber intraocular lens implantation and pars plana vitrectomy with endophotocoagulation. The mean follow-up period was 27 months. Final visual acuity was 20/40 or better in 12 of 25 eyes (48%). Of 25 eyes, five (20%) showed progression of the retinopathy after the operation, and two (8%) developed macular edema. Extracapsular cataract extraction and posterior chamber intraocular lens implantation was well tolerated in most eyes.     

眼外伤晶状体玻璃体切除术后二期IOL植入术

目的 探讨复杂性眼外伤玻璃体切除术后无晶状体眼二期人工晶状体植入术临床疗效，评估手术的可行性及安全性。方法 手术31例(31眼)，术后随访3～20月，观察视力、散光度、眼压及并发症：结果 30眼术后裸眼视力均达到或接近术前矫正视力：后房型人工晶状体睫状沟植入7眼中视力≥0．5者占28．57％，后房型人工晶状体透巩膜睫状沟缝线固定术18眼中视力≥0.5者占22．22％，虹膜型人工晶状体植入术6眼中视力≥0．5者占33．33％：1眼视力下降。结论 复杂性眼外伤行玻璃体切除术后二期人工晶状体植入，经过术前病例的选择，术中采用眼内灌注，适宜的人工晶状体植入，可获得较好的视力。     

Vitreous loss in posterior chamber lens implantation

Management of posterior capsule rupture and vitreous loss associated with intraocular lens implantation is described and the results of the procedure statistically analyzed. Vitreous loss occurred in 18 (4.3%) of the 416 eyes treated during a one-year period. Of these 18 eyes, 11 received posterior chamber lenses and seven received anterior chamber lenses; all lenses remained adequately fixated. The visual acuity, incidence of postoperative complications, and endothelial cell loss were not significantly different in the eyes that had posterior capsule rupture and vitreous loss and in the control eyes. Although posterior chamber lens implantation is not necessarily contraindicated in eyes with vitreous loss, instances of high endothelial cell loss suggest the need for greater attention to the endothelial cells during vitrectomy.     

Comparison of corneal endothelial changes after use of different adjuncts during lens implantation

To evaluate postoperative changes in corneal endothelial cell density, we conducted a retrospective study in 34 patients (35 eyes). Patients underwent extracapsular cataract extraction and posterior chamber lens implantation using an air bubble (23 eyes), sodium hyaluronate (Healon) (6 eyes), or air bubble plus sodium hyaluronate (6 eyes). The endothelial cell density of all eyes decreased from 2496±341 cells/mm² preoperatively to 1539±371 cells/mm² 1 month postoperatively. The endothelial cell loss rate was 21%, 31%, and 29% in the air bubble, sodium hyaluronate, and air bubble plus sodium hyaluronate groups, respectively (P>.05).     

Pseudophakic retinal detachment.

We reviewed 165 cases of non-referred pseudophakic retinal detachment. Fifty-three eyes (32%) had sustained significant complications due to cataract surgery prior to retinal detachment; 45 eyes (27%) presented with grade B, C or D proliferative vitreoretinopathy. The overall reattachment rate was 84%. This was significantly higher in the posterior chamber lens group than in the iris-fixated lens or anterior chamber lens groups (93 vs. 69 and 81%). Our data show that uneventful extracapsular cataract extraction plus posterior chamber lens implantation offers the best chance of successful detachment surgery.     

黏弹剂选择对百康复视伦有晶状体眼人工晶状体的影响

目的观察黏弹剂对百康复视伦有晶状体眼后房屈光晶状体（PC—PRL）植入手术的影响,分析可能的影响因素。设计实验研究。研究对象36只新西兰标准实验兔（36眼）。方法将36只实验动物随机分为6组,每组6只,右眼为手术眼。将两种相同材料的人工晶状体A和B（LA,LB）及三种黏弹剂A,B,C（EA,EB,EC）进行不同组合（LA＋EA,LA＋EB,LA＋EC,LB＋EA,LB＋EB,LB＋EC）植入动物眼内,其中LA＋EA为临床中发生术后人工晶状体后表面混浊的PC—PRL＋HealonGV。手术后1天观察人工晶状体表面混浊情况。术后2天－1周,将裂隙灯观察到发生混浊膜的实验兔处死,手术剥取人工晶状体表面纤维膜,电镜下观察。对于术后发生增生膜的组合,使用人眼房水作为培养基,进行人工晶状体与相应黏弹剂的体外培养,并观察晶状体表面的蛋白沉淀情况。主要指标前房闪光,人工晶状体表面增生膜。结果在动物体内实验中观察到仅在PC—PRL与HealonGV配合使用的动物组,5眼（83．33％）术后发生人工晶状体后表面混浊,与其他组比较差异有统计学意义（χ^2=16．31,P=0．006）。电镜下显示混浊为纤维增生。体外培养各组均未发生该现象。结论PC—PRL与HealonGV在术中共同使用是术后人工晶状体后表面混浊的原因,其机制尚需进一步研究。（眼科,2010,19：93－96）     

The effect of viscoelastic substances on postsurgical blood aqueous barrier

A postsurgical flare was evaluated with a flare-cell meter and the effect of residual viscoelastic substances on the blood aqueous barrier function was studied. The materials consisted of 100 eyes undergoing extracapsular cataract extraction and posterior chamber lens implantation using sodium hyaluronate products (Healon:Pharmacia and Opegan:Santen). The molecular weight is 1.9-3.6 million daltons in Healon and 0.9-1.2 million daltons in Opegan. According to the aqueous warm current on the 1st postoperative day, the eyes were divided into two groups; the poor current group and the normal current group. The poor current group consisted of 13 eyes had static aqueous current, probably due to residual viscoelastic substances from the clinical findings, namely a little pain, foggy general corneal edema and spontaneous recovery of the warm current without specific administrations of antibiotics. Eyes with poor current were recognized in 18% (11/62) among cases with Healon and 5% (2/38) in case with Opegan. Flare values of the poor current group were higher in 7 eyes than the highest of the normal current group on the 1st postoperative day. After the 2nd postoperative day, the median flare value of the poor current group was higher than that of the normal current group. The difference was statistically significant throughout the first week (p less than 0.02). The cell number was also higher in the poor current group on the 1st and 2nd postoperative day (p less than 0.02). These findings suggest that the residual viscoelastic materials may increase the breakdown of blood-aqueous barrier and/or interfere the barrier recovery.     

A prospective comparison of 4% polyacrylamide (Orcolon) and 1% sodium hyaluronate (Healon) in cataract and intraocular lens implant surgery

We performed a prospective randomized clinical trial of 4% polyacrylamide (Orcolon) and 1% sodium hyaluronate (Healon) in routine extracapsular cataract extraction with posterior chamber lens implantation or in secondary anterior chamber lens implantation. Seventy consecutive patients were enrolled. The viscoelastic agents were compared in four areas intraoperatively: ease of injection, ease of removal, clarity of field and ability to hold back ocular tissues. Healon was significantly superior to Orcolon in all four areas. Further evaluations were performed on the first day and at 2 weeks postoperatively. Measurements of intraocular pressure (IOP) by Goldmann applanation and evaluations of corneal edema, epithelial keratitis and anterior chamber cellular reaction were recorded. Multivariable statistical analysis revealed only one difference between the two groups: significantly more patients in the Orcolon group (eight cases) than in the Healon group (two cases) had an IOP of 21 mm Hg or greater on the first postoperative day.     

Long-term corneal endothelial changes after intraocular lens implantation

We studied the morphologic characteristics of the corneal endothelium in a series of patients who had undergone phacoemulsification with intraocular lens implantation performed by one surgeon. Specular microscopy and computer-assisted morphometry were performed preoperatively and three years after surgery. Nineteen eyes that received posterior chamber lenses with intracapsular fixation had a mean endothelial cell loss of 18.1%, without any significant change in cell size (polymegethism) or shape variability (pleomorphism). Implantation of anterior chamber lenses with the posterior capsule left intact (18 eyes) caused a similar degree of cell loss (23.5%) but caused marked polymegethism and pleomorphism of the cells. Endothelial cell loss (28.5%) and morphologic changes were greatest in five eyes that received anterior chamber lenses because of a rupture of the posterior capsule.     

Endothelial Cell Density after Posterior Chamber Lens Implantation

Endothelial cell loss was determined by specular microscopy in 50 patients after extracapsular cataract extraction and posterior chamber lens implantation. An age-matched group of unoperated fellow eyes and normal phakic eyes comprised the control group. For this series, 14.7% of the central corneal endothelial cells were lost as a result of cataract surgery and lens implantation. These patients are the first group to receive a Shearing lens implant.