Postoperative Endothelial Cell Counts Research Articles

Descemet Stripping with Automated Endothelial Keratoplasty for Bullous Keratopathies Secondary to Argon Laser Iridotomy-Preliminary Results and Usefulness of Double-Glide Donor Insertion Technique

Manipulation of the endothelial donor lamella in the anterior chamber during Descemet stripping with automated endothelial keratoplasty (DSAEK) is often difficult, especially in cases with bullous keratopathies (BK) secondary to argon laser iridotomy (ALI). We developed a novel nonfolding donor insertion technique using a Busin glide and an intraocular lens (IOL) sheet glide and evaluated post-DSAEK outcomes for ALI-induced BK using several insertion techniques. Fourteen patients (mean age, 74.2 +/- 4.9 years) with ALI-induced BK underwent DSAEK; simultaneous cataract surgery was performed in 12 patients. Donor insertions were done by taco-folding (n = 4), spatula-assisted (n = 3), Busin glide-assisted (n = 2), and Busin glide/IOL glide-assisted methods (n = 5). Endothelial cell counts, postoperative visual acuity, induced astigmatism, and complications were examined over a mean follow-up period of 228.3 +/- 132.2 days (range 58-458 days). In 1 case, DSAEK was converted to penetrating keratoplasty because of difficulties in donor insertion by the taco-folding method, resulting in vitreous prolapse. Overall, mean postoperative endothelial cell count was 1654.2 +/- 532.3 cells/mm2 (range 853-2610 cells/mm2), a 44.9% reduction compared with donor counts (mean 3003.3 +/- 425.5 cells/mm2). All patients reached acuity >20/40, with 3 (23.1%) reaching 20/20. Mean induced astigmatism in measurable cases was 0.53D +/- 0.38D. Although nonsignificant due to the small sample size, use of Busin glide with (37.9%) or without IOL glide (37.0%) tended to cause less endothelial damage than taco-folding (49.0%) or pull-through with spatula (44.2%) at 3 months postoperatively. DSAEK is effective in eyes with ALI-induced BK. Our results suggest that insertion with a Busin glide is reliable and associated with less endothelial cell damage than the conventional taco-folding technique. Simultaneous use of IOL glide (Kobayashi double-glide method) to help prevent iris prolapse is our preferred insertion method for narrow-angle eyes.

Intraocular pressure and endothelium cell counts after cataract surgery with chitosan and sodium hyaluronate (Healon GV): 3-Year follow-up results of a randomised clinical trial

The purpose of this study was to evaluate the long-term effects of chitosan 0.1% and sodium hyaluronate 1.4% (Healon GV(R); Advanced Medical Optics, Santa Ana, CA, USA) on intraocular pressure (IOP) and endothelial cell loss. This randomised study comprised 140 eyes of 140 patients with age-related cataracts undergoing phacoemulsification followed by posterior chamber intraocular lens (IOL) implantation; 70 received chitosan 0.1%, and 70 received sodium hyaluronate 1.4%. The IOP was measured with standard Goldman applanation tonometry pre-operatively and 1 day, 1 week, 1 month, 3 months, 1 year and 3 years postoperatively. Endothelial cell counts were performed pre-operatively and 1 week, 1 month, 3 months, 1 year and 3 years postoperatively using a Pro/Koester WFSCM contact endothelial microscope. There were no significant differences found in postoperative IOP levels among the chitosan and sodium hyaluronate groups (P>0.05). No significant differences were found in postoperative mean endothelial cell counts at all time points between the chitosan and sodium hyaluronate groups (P>0.05). Chitosan has the same effects as sodium hyaluronate on IOP and endothelium cells counts after cataract surgery and IOL implantation, and therefore may be an alternative ophthalmic viscoelastic device.

Queratoplastia penetrante protegida: técnica quirúrgica y respuesta del endotelio

To describe the technique and to evaluate the safety of protected penetrating keratoplasty (PPK). A technique for penetrating keratoplasty is described. The postoperative endothelial cell counts of 17 eyes in which this operative technique was used were compared with those in 24 eyes in whom the standard operative technique for penetrating keratoplasty (PK) was used. The post-operative time periods were grouped as follows: 3-6 months, 7-12 months and >12 months. For statistical analysis, the Mann-Whitney U non-parametric test was employed. There was no case where tissue extrusion occurred during the procedure. The endothelial cell count was similar in both groups for the 3-6 month period (PK = 2,086, DS 566; PPK = 1,858, DS 671; p = 0.2702) and >12 months period (PK = 1,574, DS 745; PPK = 1,419, DS 810; p = 0.2882). There was a significant difference in the 7-12 month period (PK = 2,255, DS 831; PPK = 1,569, DS 623; p = 0.0397). The described technique of PPK may reduce the risk of per-operative complications. Damage to the endothelium is not increased compared with that seen following the standard PK procedure.

Preliminary outcomes of primary phacoemulsification plus intraocular lens implantation for primary angle-closure glaucoma

To evaluate effects and safety of primary phacoemulsification plus intraocular lens implantation for controlled chronic angle-closure glaucoma (CACG) or primary angle-closure (PAC). Prospective, non-randomized comparative trial. Two treatment groups were used. The IOL group included the use of phacoemulsification plus intraocular lens (IOL) implantation in 27 eyes. The LI group included treatment by laser iridotomy (LI) in 23 eyes. Intraocular pressure (IOP), numbers of anti-glaucoma medications, complications, and corneal endothelial cell counts were examined in each group. In the IOL group, IOP was significantly reduced from a preoperative mean of 14.8 +/- 4.2 mmHg to a 6-month-postoperative mean of 10.8 +/- 1.6 mmHg (P < .05). However, in the LI group, mean preoperative IOP was 15.5 +/- 4.1 mmHg, and the 6-month-postoperative IOP was 14.7 +/- 4.7 mmHg (P = .76). In the IOL group, no patient used anti-glaucoma medications 6-month postoperatively, whereas in the LI group, mean number of anti-glaucoma medications was 0.2 +/- 0.4 (P < .05). There were no significant differences in preoperative and postoperative corneal endothelial cell counts between IOL and LI groups (P = .39). Primary phacoemulsification plus intraocular lens implantation for controlled CACG or PAC seems to be a safe and effective method in reducing IOP. This procedure might become the first treatment of choice for controlled CACG or PAC with cataract.

Endothelial Keratoplasty Using Donor Tissue Not Suitable for Full-Thickness Penetrating Keratoplasty

To evaluate the use of corneal donor tissue deemed unsuitable for full-thickness penetrating keratoplasty (PK) for use in deep lamellar endothelial keratoplasty (DLEK) and to compare postoperative results to those of DLEK surgery using donor tissue that is suitable for PK. Small-incision DLEK surgery was performed using 39 donor corneas unsuitable for PK. Thirty-five donors had anterior scars or opacities, 3 donors had pterygia within the 8-mm zone, and 1 had prior LASIK. All donor preparation was completed by manual stromal dissection. The DLEK surgical and postoperative courses were reviewed. Preoperative and 6-month postoperative results of this study group were compared with a control group consisting of the first 55 consecutive small-incision DLEK patients receiving donor corneas that had no criteria excluding them from use in PK. Four eyes in the study group and 1 eye in the control group had the confounding variables of the presence of an anterior-chamber lens or surgical vitrectomy with macular disease in the recipient eye. There was no significant difference in preoperative measurements of best spectacle-corrected visual acuity (BSCVA; P = 0.372), donor endothelial cell density (ECD; P = 0.749), or corneal topography [surface regularity index (SRI), P = 0.485; or surface asymmetry index (SAI), P = 0.154] between the 2 groups. For the patients receiving corneas deemed unacceptable for PK, at 6 months after surgery, the vision (P = 0.002) and corneal topography measurements improved significantly from before surgery (SRI, P < 0.001; SAI, P < 0.001), and there was no significant change in refractive astigmatism (P = 0.240). There was a significant difference in the vision at 6 months postoperatively between the overall study group and the control group, with the mean vision of the study group at 20/56 and the control group at 20/43 (P = 0.015). If eyes with known cystoid macular edema (CME) and vitrectomy are removed from each group, there is no significant difference in vision at 6 months between the study group and the control group (P = 0.110), with the average BSCVA of those receiving donor corneas unsuitable for PK equal to 20/48 (range, 20/25-20/200) and the average vision for those receiving PK-acceptable donor tissue equal to 20/43 (range, 20/20-20/80). The 6-month average refractive astigmatism of the study group was 1.12 +/- 0.99 D (range, 0.00-4.00 D), and the average endothelial cell count was 2064 +/- 396 cells/mm(2) (range, 1208-2957 cells/mm(2)). There was no significant difference in 6-month postoperative endothelial cell count (P = 0.443), refractive astigmatism (P = 0.567), or corneal topography (SRI, P = 0.332; SAI, P = 0.110) in study patients who received corneas unsuitable for PK compared with control patients who received corneas suitable for PK. Endothelial keratoplasty such as DLEK surgery with manual donor preparation broadens the donor pool by enabling corneas that cannot be used for PK to be used for selective endothelial transplantation without deleterious postoperative results.

Comparison of Outcomes of Primary Scleral-Fixated versus Primary Anterior Chamber Intraocular Lens Implantation in Complicated Cataract Surgeries

To compare the visual outcomes and complication profiles of primary scleral-fixated intraocular lens (SFIOL) versus primary anterior chamber intraocular lens (ACIOL) implantation in cataract surgeries complicated by inadequate capsular support. Retrospective, interventional, comparative cases series. Thirty-six eyes of 36 patients undergoing SFIOL implantation (group 1) and 46 eyes of 46 patients undergoing ACIOL implantation (group 2). Retrospective analysis of medical records of a consecutive series of complicated cataract surgeries with primary SFIOL or ACIOL implantation. Postoperative best-corrected visual acuity (BCVA), intraoperative and postoperative complications, if any, and postoperative corneal endothelial cell counts. A multiple linear regression model was constructed with postoperative BCVA as the dependent variable and with IOL group (SFIOL vs. ACIOL), preoperative BCVA, surgeon's operative experience, planned operation, and patient's age as independent variables. Fifty-eight percent (group 1) and 37% (group 2) of patients underwent phacoemulsification, whereas the rest underwent extracapsular cataract extraction. The mean postoperative follow-up was 33.4+/-17.9 months (range, 6-61 months). Postoperative Snellen BCVA of 20/40 or better was achieved in 47.2% (group 1) and 71.7% (group 2) of patients (P = 0.038). Regression analysis showed that primary ACIOL implantation was associated with a significantly better postoperative BCVA of -0.157 on the logarithm of minimum angle of resolution scale (95% confidence interval, -0.306 to -0.007; P = 0.040), compared with primary SFIOL implantation. Although both the number of eyes with complications and the total number of complications were higher in the SFIOL group, the differences in early (P = 0.073) and late (P = 0.377) complications were not statistically significant. The results indicate that satisfactory results are achieved with primary implantation of current open-loop ACIOLs during cataract surgery complicated by loss of posterior capsule integrity. Eyes with these IOLs fared better than a cohort of eyes undergoing SFIOL implantation in a similar situation, at intermediate-term follow-up. Further prospective clinical trials with longer follow-up may help to evaluate the long-term visual outcomes and complication profiles after primary implantation of these lenses.

Deep Lamellar Endothelial Keratoplasty: Surgery in Complex Cases With Severe Preoperative Visual Loss

This study was designed to report the use of deep lamellar endothelial keratoplasty (DLEK) in combination with other intraocular surgeries in the treatment of eyes with severe bullous keratopathy and visual loss. DLEK surgery was performed in six patients with severe bullous keratopathy and preoperative vision with a range of between count fingers and light perception only. DLEK was combined with vitrectomy and placement of a ciliary sulcus sutured intraocular lens in four patients and with cataract surgery in one patient. Two patients with vitreoretinal disease underwent pars plana vitrectomy within only 4 months after the DLEK donor tissue had been placed. Graft clarity, Snellen visual acuities, refractive astigmatism, endothelial cell counts, and corneal topography were prospectively measured at 6 and 12 months postoperatively. At 6 months after DLEK surgery, all grafts were clear and vision improved in all patients. Best spectacle-corrected visual acuity improved from count fingers level (or worse) before surgery to a range of 20/40 to 20/200 after surgery. Average refractive astigmatism at 6 months was 2.0 diopters (range, 0.50-4.00 diopters). The average postoperative endothelial cell count was 1,679 +/- 380 (range, 1,200-2,298) cells/mm at 6 months and 1,449 +/- 365 (range, 1,105-2,043) cells/mm at 12 months. Vitreoretinal surgery subsequent to graft placement did not affect corneal clarity or dislodge the grafted tissue. DLEK surgery can be used in cases with severe visual loss caused by bullous keratopathy with transfer of healthy donor endothelium, clearing of the central cornea, and restoration of useful vision. DLEK also can be successfully combined with other intraocular surgeries such as vitrectomy, intraocular lens exchange, and sutured intraocular lens surgery. The DLEK graft can tolerate subsequent intraocular surgery performed as early as 3 months after placement of the donor tissue.

Small-Incision Deep Lamellar Endothelial Keratoplasty (DLEK)

To evaluate the visual, topographic, and endothelial survival results in 25 consecutive patients who have received small-incision deep lamellar endothelial keratoplasty (DLEK) transplant surgery. DLEK surgery was performed in 25 patients with Fuchs endothelial dystrophy or pseudophakic bullous keratopathy utilizing a 5-mm scleral access incision. Snellen visual acuities, refractive astigmatism, endothelial cell counts, and corneal topography were prospectively measured at preop and at 6 months after small-incision DLEK endothelial replacement surgery. Best spectacle-corrected visual acuity improved from an average of 20/90 (range 20/25 to 2'/200) before surgery to an average of 20/44 (range 20/25 to 20/200, P < 0.001) 6 months after surgery, with 56% of patients 20/40 or better at 6 months. Average refractive astigmatism at 6 months was 1.31 +/- 0.59 diopters (range 0.25 to 2.50 diopters), representing an average increase in astigmatism of 0.45 diopters from preop. Despite folding of the donor graft for placement into the recipient posterior lamellar bed, the average postoperative endothelial cell count at 6 months was 2122 +/- 510 cells/mm2 (range 1097 to 3202 cells/mm2) or an average 24% cell loss from donor eye preop measurements, a level of cell loss comparable to that reported after PK or after large-incision DLEK surgery. Small-incision DLEK surgery preserves the recipient corneal topography, resulting in very little change in astigmatism from preop. The excellent postoperative donor endothelial cell counts attest to the survival of donor endothelium despite folding of the graft for insertion. The small-incision DLEK technique may become the standard for endothelial replacement surgery in the future.

Endotoxin in storage medium of human corneal grafts and clinical course after penetrating normal-risk keratoplasty.

It is well known that endotoxins in storage medium may stimulate cytokine production and expression of adhesion molecules as well as endothelial damage in human corneal grafts. It has been supposed that endotoxin exposure of corneal grafts may, therefore, cause immune reactions and lead to reduced endothelial cell count after penetrating keratoplasty. It was the purpose of this prospective study to evaluate if this hypothesis is true. A consecutive series of 274 samples of sterile organ culture storage medium from 274 human corneal grafts was collected between August 1998 and February 1999 and tested for endotoxin using Limulus amebocyte-lysate assay (LAL) after 7 days of organ culture. Threshold endotoxin level was set at 1.0 U/ml. A total of 161 grafts were transplanted and 113 were discarded. Within the 161 corneas transplanted, 62 were grafted to normal-risk patients and 99 to high-risk patients. Only normal-risk keratoplasty patients were included in the study and followed for at least 10 months. Immune reactions, graft failures, and postoperative endothelial cell counts were recorded. The mean endotoxin level in organ culture medium of all transplanted grafts was 1.07+/-2.96. Mean endotoxin level in organ culture medium of discarded grafts was 1.68+/-5.76, with 71 samples being below and 42 above the threshold of 1.0 U/ml called endotoxin-negative and endotoxin-positive, respectively. In all 36 culture medium samples from the 62 grafts transplanted to the group of normal-risk keratoplasty patients were endotoxin-negative and 26 endotoxin-positive. An influence of endotoxin levels on incidence of immune reactions, graft failure, and postoperative endothelial cell counts could not be revealed in patients with normal-risk keratoplasty. Low endotoxin levels in storage medium neither seem to promote immune reactions nor to contribute to postoperative chronic endothelial cell loss in normal-risk keratoplasty patients.

Long-term endothelial cell loss after phacoemulsification: peribulbar anesthesia versus intracameral lidocaine 1%. Heuermann T, Hartmann C, Anders N. J Cataract Refract Surg 2002;28:639–643.

The use of topical anesthesia in cataract surgery has become increasing popular in the past decade. In 1990, only 10% of cataract surgery in the United States was performed with topical anesthesia, while over 33% of cases were done with topical anesthesia in 1998. Most (82%) ophthalmic surgeons supplement topical anesthesia with intracameral lidocaine. There is clinical and experimental evidence that intracameral anesthesia may be toxic to intraocular structures, especially the corneal endothelium, where abnormal ultrastructural and morphologic changes have been reported. There are a few prospective clinical trials with long-term follow-up that specifically address this concern. The authors performed a prospective, randomized clinical trial in which 78 patients undergoing clear corneal phacoemulsification and posterior chamber IOL implantation by a single surgeon (N.A.) received either peribulbar (39 eyes) anesthesia or topical anesthesia supplemented with 0.15 cc of unpreserved 1% lidocaine. The mean surgical time was 12.2 minutes with peribulbar anesthesia and 14.0 minutes with topical/intracameral lidocaine anesthesia (P < .01). After a mean follow-up of 20 ± 5.1 (SD) months, there were no statistically significant differences between the peribulbar and topical/intracameral lidocaine groups in mean preoperative (2,341 vs 2,512 cells/mm2) and postoperative (2,082 vs 2,197 cells/mm2) endothelial cell counts, mean endothelial cell loss from preoperatively to postoperatively (11.11% vs 12.55%), mean endothelial cell size (496 μm vs 470 μm), and the amount of hexagonal cells (58% vs 56%). There were no intraoperative or postoperative complications in either group. The authors conclude that topical anesthesia supplemented with 0.15 cc of unpreserved 1% lidocaine is a safe alternative to peribulbar anesthesia for phacoemulsification.—Michael D. Wagoner

Phacoemulsification in the anterior chamber

Purpose: To evaluate anterior chamber phacoemulsification as an alternative to an endocapsular procedure. Setting: Instituto Oftalmológico de Alicante, Alicante, Spain. Methods: In this prospective randomized masked clinical trial, 60 eyes of 30 patients had cataract extraction by phacoemulsification. A conventional stop-and-chop technique was used in 30 eyes; the other 30 had surgery by the phaco-out technique in which the nucleus was prolapsed into the anterior chamber using extensive hydrodissection. Copious sodium hyaluronate 3.0%-chondroitin sulfate 4.0% (Viscoat®) and hydroxypropyl methylcellulose were used to protect the cornea and iris. The phaco time and power, postoperative inflammation, corneal edema (clinically and by pachymetry), and endothelial cell count between groups preoperatively and postoperatively were compared. All patients completed a 3-month follow-up. Postoperative examinations were at 3 days, 2 weeks, and 1 and 3 months. Results: The mean nuclear hardness was 2.67 ± 0.61 (SD) in the stop-and-chop group and 2.65 ± 0.71 in the phaco-out group. The power-to-time ratio was 18.47 and 18.80, respectively. The mean endothelial cell loss was 11.18% ± 4.24% in the stop-and-chop group and 11.20% ± 5.60% in the phaco-out group. There were no significant differences between groups in any parameter ( P > .05, independent-sample t test). Conclusion: Phacoemulsification in the anterior chamber was as safe as endocapsular phacoemulsification using a stop-and-chop technique. This technique is fast and easier to learn than endocapsular phacoemulsification.

Anterior capsule staining using 0.025% trypan blue in cataracts without red reflex

Purpose: To describe the use of anterior capsule staining in cataracts without red reflex using a 0.025% trypan blue solution. Methods: Six eyes of 6 patients with cataracts without red reflex were submitted to phacoemulsification using a direct injection of 0.2 to 0.5 ml of 0.025% trypan blue in the anterior chamber previous to viscoelastic injection. All patients had an ophthalmologic examination prior to surgery, as well as pre and postoperative corneal endothelial cell count. Results: In all cases the capsule became stained with a faint blue color that enabled an adequate visibility of the flap during the continuous curvilinear anterior capsulotomy (CCC). There were no intra-or postoperative complications. The endothelial cell loss varied between 1.8% and 26.6% (mean 12.8%). Conclusion: Staining the anterior capsule with 0.025% trypan blue solution allows a good visibility of the capsular flap and facilitates the confection of CCC in cataracts without red reflex.

Corneal Refractive and Endothelial Changes Following THC:YAG (Holmium) Laser Sclerostomy

To determine the effect of THC:YAG (holmium) laser sclerostomy on corneal curvature and endothelial cell counts. One hundred twenty-five cases were reviewed for high postoperative corneal astigmatism (> 5 D) or preoperative and postoperative endothelial cell count measurements in eyes without preoperative evidence of corneal endothelial compromise. Nine patients had keratometry reading at 2 to 3 months with documented corneal astigmatic changes of 5.62 to 12 D (mean 7.27 +/- 2.16 D). Sixteen eyes of 14 patients studied with specular microscopy had central mean endothelial cell count reductions of 6.5% following THC:YAG laser sclerostomy. The total energy applied correlated with the percentage reduction in endothelial cell counts (r = .507, P = .045, n = 16, Spearman correlation). Higher laser energy levels can result in high corneal astigmatism, which in some cases may be persistent, and a reduction in endothelial cell count.

Neodymium:YAG laser lens ablation in a rabbit model

Purpose: To assess the safety of neodymium:YAG (Nd:YAG) laser lens ablation in a rabbit model prior to human investigation.Methods: The Nd:YAG laser lens ablation probe was inserted into the anterior chamber of 14 New Zealand white rabbit eyes and Nd:YAG laser lens ablation was simulated, exposing the eyes to energy significantly higher than that used in previous experimental Nd:YAG lens ablation of the human crystalline lens. After the procedure, the rabbits were killed at 1 hour, 1 day, or 1 week and the eyes evaluated by specular microscopy, ultrasonic pachymetry, and light microscopy.Results: There was no statistically significant difference in the postoperative endothelial cell counts or ultrasonic pachymetry of study eyes and control (unoperated) eyes. Light microscopy revealed no apparent damage to the cornea, trabecular meshwork, or retina of the study eyes.Conclusions: The Nd:YAG laser lens ablation device appears to be a safe method of cataract removal in this animal model. Further study is needed to determine the safety and efficacy of this device for cataract removal in humans.

Endothelial cell loss after 4 mm cataract surgery

To assess whether a 4 mm scleral tunnel incision with a 1.5 mm internal corneal lip (three-step procedure) causes increased endothelial cell loss and damage to the cornea, we retrospectively evaluated the outcomes of 20 patients (40 eyes) who had a standard 4 mm scleral tunnel incision (two-step procedure) in one eye followed by a three-step incision in the second eye, with in situ phacoemulsification and insertion of a foldable silicone lens in each eye. Mean phacoemulsification time was 2.4 ± 1.1 minutes for the two-step incisions and 3.4 ± 1.4 minutes for the three-step incisions. Preoperative and postoperative endothelial cell counts were obtained to determine the effects of surgery on the corneal endothelium. Although the three-step procedure had a trend toward increased endothelial cell loss from the central corneal region compared with the two-step incision, the result was neither clinically nor statistically significant. The difference between the three-step and two-step incisions in postoperative endothelial cell counts from the superior corneal region was statistically significant. The difference in postoperative counts from the inferior region was not statistically significant. Although the three-step 4 mm incision does seem to affect the corneal endothelium, its clinical significance is unknown.

2% hydroxypropyl methylcellulose as a viscous surgical adjunct: A multicenter prospective randomized trial

A multicenter prospective trial was conducted comparing preoperative and postoperative endothelial cell counts in patients who had extracapsular cataract extraction with posterior chamber lens implantation or phacoemulsification and posterior chamber lens implantation. One hundred sixty six eyes received 2% hydroxypropyl methylcellulose (Occucoat®) and 56 eyes received sodium hyaluronate (Healon®). The average cell loss in the Occucoat group was 12.1%; in the Healon group it was 10% (P = NS). There was no significant difference between the two groups in intraocular pressure at 24 hours. In this study Occucoat was as effective in protecting the corneal endothelium as Healon.

The Effects of Nd:YAG Laser Iridotomy on the Corneal Endothelium

We studied 18 eyes of 18 patients undergoing Nd:YAG laser peripheral iridotomy for occludable anterior chamber angles. A Q-switched laser was used for all treatments. Preoperative and postoperative pachymetry and corneal endothelial cell counts were obtained centrally, in the nontreated superonasal quadrant, and in the treated superotemporal quadrant. No significant differences were found between preoperative and postoperative corneal thickness at any site. A small decrease in endothelial cell count (95 cells/mm2) at the treated site was statistically significant (P = .04).

Effects of Argon Laser Iridotomy on the Corneal Endothelium

We studied 14 eyes of 14 patients undergoing argon laser peripheral iridotomy for occludable (narrow) anterior chamber angles. Preoperative and postoperative pachymetry and corneal endothelial cell counts by specular microscopy were obtained centrally and in both the treated and nontreated superior quadrants. No significant differences were found between preoperative and postoperative measurements of corneal thickness and endothelial cell counts in any area.

Neodymium-YAG laser posterior capsulotomy. Central corneal endothelial cell density.

We determined central corneal endothelial cell densities in 39 eyes in a masked fashion before and after Q-switched neodymium-YAG laser posterior capsulotomy. The mean preoperative endothelial cell count was 1,840 cells per square millimeter (SD, 611 cells per square millimeter; range, 522 to 2,742 cells per square millimeter). The mean postoperative endothelial cell count was 1,798 cells per square millimeter (SD, 600 cells per square millimeter; range, 478 to 2,750 cells per square millimeter). The difference between the mean preoperative and postoperative cell density was 42 cells per square millimeter (2.3% cell loss). There was no significant correlation between central corneal endothelial cell loss and the laser energy used, pseudophakic status (posterior chamber intraocular lens vs no intraocular lens), size of capsulotomy, vitreocorneal touch, or preoperative corneal endothelial cell density.

Effect of BSS Plus on the Corneal Endothelium with Intraocular Lens Implantation

BSS Plus, a new intraocular irrigating solution, was compared to BSS (Balanced Salt Solution) in 100 cases of planned extracapsular cataract extraction with the insertion of a Simcoe posterior chamber intraocular lens. Surgery was standardized in all cases, and Healon was not used. Fifty patients received BSS Plus at surgery and 50 patients received BSS. Approximately 10–20 min of introcular irrigation was required for each case. Preoperative and postoperative corneal endothelial cell counts showed a decrease in cell density of 15.4% using BSS Plus, and a decrease of 22.7% using BSS. These differences were statistically significant (p < 0.05).