Specular Microscopic Findings Research Articles

Donor Endothelial Cell Density Not Changed Immediately After Ex Vivo Corneal Cross-Linking

Purpose: The aim of this study was to evaluate the effect of corneal cross-linking on central endothelial cell density (ECD) by comparing masked measurements before and immediately after preparation of cross-linked (CXL) and non–cross-linked (non-CXL) donor corneas. Methods: Thirty donor corneas were randomized 1:1 to either CXL or non-CXL using a modified Dresden protocol. Specular microscopic images of the central corneal endothelium were obtained within 36 hours of recovery and within 3 hours of preparation completion. Images were sent to a central cornea image analysis reading center for ECD determination in a masked, dual-graded manner. Results: Before and after preparation, the mean ECD was 2567 ± 305 cells/mm2 and 2525± 339 cells/mm2 for the CXL group (n =15) and 2652 ± 365 cells/mm2 and 2572 ± 513 cells/mm2 for the non-CXL group (n =15), respectively. The mean difference in ECD before and after preparation was not statistically significant for the CXL and non-CXL groups (P = 0.36; P = 0.31, respectively). In addition, an independent sample t test showed no statistically significant difference in the ECD change between the CXL and non-CXL groups (P = 0.67). Conclusions: Our specular microscopic findings show that ex vivo cross-linking of donor corneas does not seem to produce acute decrease of central endothelial cell density. These findings are encouraging and assist in warranting a clinical trial examining its value in reducing refractive errors and improving postoperative visual outcomes in eyes with keratoconus that undergo keratoplasty.

Corneal characteristics in patients with retinitis pigmentosa

BackgroundTo evaluate corneal topography and specular microscopic findings in patients with retinitis pigmentosa. MethodsOne hundred and two eyes of 51 patients with retinitis pigmentosa and 60 eyes of 30 healty subjects were included in our study. A detailed ophthalmological examination involving best corrected visual acuity (BCVA) was performed. A rotating Scheimpflug imaging system, was used to evaluate all eyes for topographic and aberrometrics parameters. Specular microscopy measurements were also noted. ResultsThe retinitis pigmentosa group consisted of 51 patients (29 male and 22 female, mean age of 35.61±13.55 (18–65) years and the control group also consisted of 30 healty subjects (29 male and 22 female, mean age of 33.67±9.92 (20–58) years. There was no difference between the groups in terms of age (p = 0.624) and gender (p = 0.375). Spherical equivalents were higher in the RP group (p<0.001). Central keratoconus index (CKI) (p<0.001), Belin Ambrosio enhanced ectasia display total deviation value (BAD-D) (p = 0.003), index of surface variance (ISV) (p<0.001), index of vertical asymmetry (IVA) (p<0.001), Ambrosio related thickness (ART max) (p = 0.018), index of height asymmetry (IHA) (p = 0.009), index of height decentration (IHD) (p<0.001), maximum anterior elevation (p<0.001), front elevation in thin location (p = 0.05), progression index average (p = 0.015), root mean square (RMS) total (p = 0.010) and RMS-higher order aberration (RMS-HOA) (p<0.001) values were higher in RP group. There was a weak negative correlation between BCVA and ART max measurements (r=-0.256, p = 0.009) in RP group. We detected keratoconus-suspect in 6 eyes and clinically manifest keratoconus in one eye in the RP group. ConclusionsPatients with retinitis pigmentosa may have corneal morphological disorders that may affect vision. In our study, corneal topographic pathologies including keratoconus and possible keratoconus were detected in RP patients.

An evaluation of corneal endothelial cell morphology in patients with thyroid-associated ophthalmopathy.

To evaluate corneal endothelial cell morphology in patients with thyroid-associated ophthalmopathy (TAO). Seventy-two eyes of 36 patients with TAO presenting to the ophthalmology department between January 2018 and January 2022 were included in the study. The findings were compared with 98 eyes of 49 healthy individuals. Mean endothelial cell density (ECD), coefficient of variation (CV), maximum cell area, minimum cell area, average cell area, and hexagonality ratio were obtained using non-contact specular microscopy. The thicknesses of peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC) were measured using optical coherence tomography (OCT). The TAO group consisted of 36 patients, 11 (30.6%) men and 25 (69.4%) women, and the control group of 49 healthy individuals, 14 (28.6%) men and 35 (71.4%). No significant differences were determined between the TAO and control groups in terms of the specular microscopy findings of mean ECD, CV, or hexagonality ratio values (p > 0,05). However, the mean Hertel values differed significantly between the two groups (p = 0.001). When the TAO group was divided into two subgroups based on patients who had previously received prednisolone therapy and those who had not, significant differences were observed in terms of mean ECD, CV, and hexagonality ratio values (p > 0.05). Comparison of patients diagnosed with active TAO and receiving prednisolone therapy and the TAO patients with inactive disease revealed lower ECD, higher CV values, and lower hexagonality ratios in the prednisolone therapy group. These findings all suggest that inflammation in patients undergoing active disease affects the corneal endothelium.

Case Report: Fuchs Dystrophy after Corneal Transplantation

Fuchs Endothelial Corneal Dystrophy (FECD) consists of a progressive loss of corneal endothelial cells, with subsequent development of subepithelial connective tissue objectively leading to severely impaired vision. Generally, the time interval between the asymptomatic stage, with only the presence of guttates on biomicroscopy, to the most advanced stage, associated with chronic edema that causes corneal opacity and scarring, can vary between 20 to 30 years of evolution. Eye bank donor cornea selection includes FECD screening based on macroscopic and specular microscopyfindings. However, this screening may not be sensible enough to detect the disease in its earlier stages. We report 2 cases of FECD in corneal grafts in which the donor corneas eye bank screening was negative for FECD. These two cases highlight the importance of a meticulous evaluation of donor corneas candidates for corneal transplant. Traditional evaluation was not sensible enough to detect early phases of FECD. Additional screening methods, such as genetic testing, would improve the accuracy to detect FECD and other diseases present in donor corneas used in corneal transplants.

Association of childhood obesity with retinal microvasculature and corneal endothelial cell morphology.

To investigate the optical coherence tomography angiography (OCTA) and specular microscopy (SM) findings in obese children and compare them with healthy ones. In this prospective study, 50 eyes of 25 obese children [body mass index (BMI)≥95th percentile], 36 eyes of 18 control age- and sex- matched healthy subjects (BMI <85th percentile) were included. Demographic features and ophthalmological examination including OCTA measurements as well as SM findings were assessed. Cellular morphology was observed by noncontact SM and results for corneal endothelial cell density (cells/mm2), coefficient of variation of cell size and percentage of hexagonal cells were obtained. The OCTA was performed with 6 × 6mm sections for macula and 4.5 × 4.5mm sections for optic disc in all eyes. Foveal retinal thickness (FRT), retinal nerve fiber layer (RNFL) thickness, vessel density in different sections of retina and optic nerve head were analyzed. All SM parameters, RNFL thickness for average, and all quadrants and optic disc radial peripapillary capillary densities were similar between groups. However, FRT, flow area for choriocapillaris, superficial and deep foveal capillary densities were significantly higher in obese group when compared to controls (242.4±18.2µm vs. 232.1±16.5µm, p=0.024, 2.2±0.1mm2 vs, 2.2±0.0mm2, p=0.042, 22.4±6.9% vs. 15.6±5.5%, p=0.001, and 38.9±7.5% vs. 31.1±8.6 %, p=0.001, respectively). Obese children seem to have higher values of FRT, flow area for choriocapillaris, superficial and deep foveal capillary densities. These results may have significant implications for understanding of how childhood obesity could affect retinal microvasculature.

The findings of corneal specular microscopy in patients with type-2 diabetes mellitus

BackgroundWe aimed to compare the morphological characteristics of corneal endothelial cells in type 2 diabetic patients and age-matched healthy subjects by specular microscopy.We also aimed to determine the association of corneal morphological features with the general characteristics and laboratory data of diabetic patients, including disease duration, haemoglobin A1c (HbA1c) levels and urine albumin creatinine ratio.MethodsA total of 195 diabetic patients and 100 healthy controls were enrolled in the study. All participants underwent a complete ophthalmological examination. Corneal endothelial measurements were performed using a noncontact specular microscopy. Laboratory data including serum fasting glucose, haemoglobin A1c levels, creatinine levels, and the urinary albumin-to-creatinine ratio were recorded. Diabetic patients were further subdivided into 3 groups according to the presence and stage of diabetic retinopathy. Specular microscopy findings and central corneal thickness of all patients were compared.ResultsThe ECD and hexagonal cell ratio were significantly lower, while the average cell size, CV%, and central corneal thickness were determined to be significantly higher in diabetic patients than in healthy controls (p = 0.001). With the presence and advancement of diabetic retinopathy, the ECD and hexagonal cell ratio decreased, while the average cell size, CV%, and central corneal thickness increased. When correlation analysis was performed between corneal morphological features and laboratory data of diabetic patients, ECD showed a significant negative correlation with diabetes duration (p = 0.028). HbA1c levels, urinary albumin-creatinine ratio (p = 0.041), average cell size and CV showed a positive correlation with these parameters.ConclusionIn conclusion, keratopathy is an important complication of type 2 diabetes. With an increase in the stage of diabetic retinopathy, alterations in corneal findings also increased. In that respect, we can suggest that keratopathy should be evaluated more cautiously in diabetic patients.

Changes in Endothelial Specular Microscopy findings before and after Corneal Cross-linking

Purpose : The purpose of our study is to assess safety of CXL with epithelium removal for the treatment of KC on the corneal endothelium by using endothelial specular microscopy comparing the following parameters (cct , cv, cd, hex) before and after CXL.Patients and methods: This study was performed in Sohag ophthalmology department in Sohag university hospital in collaboration with Sohag Oyon misr centre. A total of 30 keratoconic eyes of 23 patients were evaluated for corneal thickness and endothelial cell changes before and 6 monthes after CXL (with specular microscopy).Results:Mean age of the study group was 28.70 years ± 3.5 years ranged from (22-33) years old .There was no significant difference between pre-and postoperative CCT or CD but CV increased and HEX decrease signsificantly.Conclusion: Epi-off CXL method has been firmly established to be safe on corneal endothelium , effective and the global standard of care for the treatment of progressive keratoconus.

Visual Outcome, Refractive Error and Specular Microscopy Parameters Following Successful DSAEK

Background: Descemet stripping and automated endothelial keratoplasty (DSAEK) has gained widespread popularity in the treatment of corneal endothelial dysfunction. In the present study, we evaluated the outcome of DSAEK in our center. Methods: This retrospective cross-sectional study was conducted on 60 patients, who had undergone DSAEK at least 12 months before in Khalili Hospital, Shiraz University of Medical Sciences. On follow-up, best spectacle-corrected visual acuity (BSCVA), refractive errors and specular microscopy parameters were assessed. Results: The majority of the studied eyes (49.2%) had a BSCVA within the range of 20/40 to 20/30. BSCVA was worse than 20/200 in 8 (13.3%) patients; 6 (75%) patients showed graft failure and 2 (25%) patients had graft rejection. Mean post-operative astigmatism was 0.29 ± 1.88 diopters. The mean refractive hyperopic shift was 1.30 ± 1.34 diopters. Specular microscopy indicated that 3 (5.1%) patients had cell density of less than 700 cells/mm2, but in none of the patients cell density was less than 500 cells/mm2. Furthermore, hexagonality of endothelial cells in 50% of the eyes was 54% to 67%. Mean coefficient of variant was 27.76%. Abnormal variations in specular microscopy findings were mostly confined to endothelial cell density, sparing other parameters. Conclusions: In general, results of this study demonstrated acceptable BSCVA in the average duration of one-year post-DSAEK regarding late complications such as graft failure, graft rejection and epithelial downgrowth.

Fuchs' Endothelial Corneal Dystrophy and RNA Foci in Patients With Myotonic Dystrophy.

PurposeThe most common cause of Fuchs' endothelial corneal dystrophy (FECD) is an intronic CTG repeat expansion in TCF4. Expanded CUG repeat RNA colocalize with splicing factor, muscleblind-like 1 (MBNL1), in nuclear foci in endothelium as a molecular hallmark. Myotonic dystrophy type 1 (DM1) is a neuromuscular disorder caused by a CTG repeat expansion in the 3′-untranslated region (UTR) of DMPK. In this study, we examine for RNA-MBNL1 foci in endothelial cells of FECD subjects with DM1, test the hypothesis that DM1 patients are at risk for FECD, and determine prevalence of TCF4 and DMPK expansions in a FECD cohort.MethodsUsing FISH, we examined for nuclear RNA-MBNL1 foci in endothelial cells from FECD subjects with DM1. We examined 13 consecutive unrelated DM1 patients for FECD using slit-lamp and specular microscopy. We genotyped TCF4 and DMPK repeat polymorphisms in a FECD cohort of 317 probands using short-tandem repeat and triplet repeat-primed PCR assays.ResultsWe detected abundant nuclear RNA foci colocalizing with MBNL1 in endothelial cells of FECD subjects with DM1. Six of thirteen DM1 patients (46%) had slit-lamp and specular microscopic findings of FECD, compared to 4% disease prevalence (P = 5.5 × 10-6 ). As expected, 222 out of 317 (70%) FECD probands harbored TCF4 expansion, while one subject harbored DMPK expansion without prior diagnosis of DM1. ConclusionsOur work suggests that DM1 patients are at risk for FECD. DMPK mutations contribute to the genetic burden of FECD but are uncommon. We establish a connection between two repeat expansion disorders converging upon RNA-MBNL1 foci and FECD.

Safety of Using Matrix Metalloproteinase Inhibitor in Experimental Glaucoma Filtration Surgery.

We evaluated the safety of matrix metalloproteinase (MMP) inhibitor in experimental glaucoma filtration surgery in an animal model. Fifteen New Zealand white rabbits underwent an experimental trabeculectomy and were randomly allocated into 3 groups according to the adjuvant agent: no treatment group (n = 5), 0.02% mitomycin C (MMC) soaking group (n = 5), and MMP inhibitor (ilomastat) subconjunctival injection group (n = 5). Slit lamp examination with Seidel testing, pachymetry, and specular microscopy was performed preoperatively and postoperatively. The conjunctiva and ciliary body toxicity were evaluated with scores according to the pathologic grading systems. Electron microscopy was used to examine the structural changes in cornea, conjunctiva, and ciliary body. In the ilomastat-treated group, there was no statistically significant change in central corneal thickness preoperatively and at 28 days postoperatively (P = 0.655). There were also no significant changes in specular microscopy findings over the duration of the study in the ilomastat-treated group. The conjunctival toxicity score was 1 in the control group, 1.5 in the ilomastat-treated group, and 2 in the MMC-treated group. When assessing ciliary body toxicity scores, the ilomastat-treated group score was 0.5 and the MMC-treated group score was 1.5. Transmission electron microscopy did not show structural changes in the cornea and ciliary body whereas the structural changes were noticed in MMC group. A single subconjunctival injection of MMP inhibitor during the experimental trabeculectomy showed a less toxic affect in the rabbit cornea, conjunctiva, and ciliary body compared to MMC.

The effect of intracameral epinephrine on pupil size during phacoemulsification and its postoperative effect on specular findings and macular thickness

Objective: To evaluate pupillary size and vital signs following intraoperative intracameral adrenaline during phacoemulsification and postoperative effect of on co specular microscopy findings and macular thickness by OCT. Methods: A prospective interventional study carried out from December 2014 to December 2015 on 90 eyes. They were divided randomly into further 6 groups (15 each). The inclusion criteria consisted of no history of ocular pathologic conditions, trauma, previous ocular surgery, or recent ocular medication use. All patients were dilated preoperatively by phenylephrine 10% and operated under local peribulbar anesthesia. Then systemic monitoring regarding (pulse rate, blood pressure) and measurement of the horizontal pupil diameter by a caliper to the nearest 0.25mm pre and post intracameral adrenaline injection. Results: In our study there were great effect for intracameral epinephrine, with concentrations used, in dilatation and maintainance of papillary dilatation, The mean pre intracameral epinephrine was 4.53± 1.27 mm.The mean post epinephrine papillary diameter was 6.46± 1.00 mm. Three cases from group 1/10000 weren't dilated properly. Also three cases from group 1/9000 weren't dilated properly after intracameral epinephrine. Conclusion: Intracameral epinephrine even in higher concentrations is effective in papillary dilatation especially in cases with long duration and poorly dilated cases by usual topical mydriatics.

Corneal endothelium in xeroderma pigmentosum: clinical specular microscopy study

AimsXeroderma pigmentosum is a condition caused due to a defective DNA repair mechanism when exposed to ultraviolet radiation. Many of the patients with this disorder develop severely oedematous cornea with...

Nodules Arising Within Port-wine Stains: A Clinicopathologic Study of 31 Cases

Nodules are seen in approximately 10%-30% patients within port-wine stains (PWS) and usually regarded as vascular "tumor." However, nodules arising within PWS have not been systematically examined and the precise pathologic characteristics of them are unknown. The aim of this study is to evaluate the clinicopathologic and immunohistochemical features of blood vessels of nodules in 31 cases. A total of 31 biopsy specimens (excision) were obtained from the representative areas of lesion of each patient with nodules. Clinical features of all patients were recorded. Hematoxylin and eosin staining, immunohistochemical staining, and Weigert elastic stain were performed to investigate the histopathologic features of nodules. In a total of 31 subjects, there are 16 patients whose nodules occurred in the area innervated by the second branch of the trigeminal nerve (51.6%), 4 in the first branch (12.9%), 6 in the third branch (19.4%), 2 in both the first, and the second branch (6.5%). Based upon specular microscopic findings, 14 biopsy specimens were designated as pyogenic granuloma (PG) (45.1%), 10 as arteriovenous malformation (AVM) (32.3%), 5 as both (16.1%), and 2 cases as cavernous-like vascular ectasia (6.5%). Moreover, both AVM and PG were prone to occurring in the area innervated by the second branch of the trigeminal nerve. In summary, we believed that both AVM and PG are not rare histologic changes in PWS. Moreover, histologic findings suggest that the major portion of nodules arising within PWS can be categorized into AVM, PG, and AVH associated with PG.

Posterior Polymorphous Dystrophy and Keratoglobus in a Child

A 13-year-old boy presented with gradually progressive deterioration of vision in both eyes, bilateral photophobia, and regular headaches. Clinical examination, anterior segment findings, and specular microscopy findings were consistent with the diagnosis of posterior polymorphous dystrophy and keratoglobus. To the authors' knowledge, this is the first pediatric case and the second case overall of the simultaneous occurrence of posterior polymorphous dystrophy and keratoglobus.

Corneal Endothelial Dysfunction Associated With Amantadine Toxicity

To describe bilateral corneal endothelial dysfunction in a patient with Parkinson disease who was treated with long-term amantadine. We employed an A-B-A-B single-subject research design that included clinical history, clinical findings, photographic images, and specular microscopic findings of ocular changes. A 52-year-old woman with Parkinson disease who had taken amantadine for 6 years had bilateral corneal edema for 2 months at baseline. After cessation of amantadine, the edema resolved, and the endothelial cell densities were <or=600/mm. Corneal edema recurred when the administration of amantadine was resumed. Therefore, amantadine was permanently discontinued and the cornea cleared again. Amantadine can cause reversible corneal edema but can irreversibly reduce the density of endothelial cells.

Clinical and Specular Microscopic Manifestations of Iridocorneal Endothelial Syndrome

Purpose: To investigate the correlation between the clinical pictures and the specular microscopic findings in patients with iridocorneal endothelial (ICE) syndrome. Methods: The records of 15 patients with ICE syndrome who presented at the National Taiwan University Hospital between 1993 and 1996 were examined. The medical history, clinical pictures of the cornea, iris and anterior chamber angle, intraocular pressure, specular microscopic findings, and the correlation between clinical and specular microscopic findings were assessed. Results: Endothelial changes in specular micrographs were found in all the patients, even in those patients with minimal angle involvement by peripheral anterior synechiae. Corneal decompensation resulting in corneal edema and bullae formation was the main cause of visual impairment. Neither ICE grading nor endothelial cell density correlated with corneal edema or intraocular pressure, but they correlated with the angle involvement in ICE syndrome. The intraocular pressure was difficult to control in 8 of these patients, even after treatment with anti-glaucoma agents and trabeculectomy, especially in the patients with Cogan-Reese syndrome. Conclusion: Although specular microscopy provides an invaluable method for the diagnosis of ICE syndrome, it is not a reliable tool for predicting prognosis. Close follow-up of intraocular pressure and early detection of glaucoma are important steps to preserve visual functions in patients with ICE syndrome.

Twenty-three Cases of Primary Cornea Guttata

Purpose: An evaluation of the clinical aspects of patients with primary cornea guttata and the morphology of their corneal endothelial cells. Methods: Twenty-three patients who visited Kanazawa Medical University Hospital or related hospitals in Ishikawa or Fukui prefectures and were diagnosed as having primary cornea guttata by slit lamp microscopy and contact specular microscopy underwent an analysis of corneal endothelial cells as well as their clinical status. Results: In 23 cases, the number of men and young people under 30 years of age was low, with 4 and 2 cases respectively. There was no visual impairment due to cornea guttata. In the specular microscopic findings, the size and density of dark areas varied according to each case and there was asymmetry in some cases. The parameters of the endothelial cells, comprising mean cell area, hexagonality, and the coefficient of variation, were almost within normal limits except for one eye of a 79-year-old man who was speculated to be at an early stage of Fuch's endothelial corneal dystrophy. Three cases had received cataract surgery, but showed no statistical changes in endothelial morphology before or after the surgery. Conclusion: Cornea guttata is thought to be a disease which is not uncommon in Japanese people and which does not bring about visual impairment or abnormalities in corneal endothelial cell parameters except for a small number of patients. Such cases with remarkably decreased cell densities should be considered to be at an early stage of Fuch's dystrophy.

Two year results: sharp versus rounded optic edges on silicone lenses

Purpose To evaluate the role of optic edge design of 2 silicone intraocular lenses (IOLs) in 2 year clinical results. Setting Department of Ophthalmology, University of Vienna, Medical School, Allgemeines Krankenhaus, Austria. Methods In this comparative clinical study, 50 eyes had phacoemulsification and implantation of a high-refractive 3-piece silicone IOL with sharp optic edges (CeeOn™ model 911F) (n = 25) or a 3-piece silicone lens with rounded optic edges (CeeOn™ model 920) (n = 25). Biomicroscopic findings, including those of specular microscopic examination of the anterior lens surface, were documented and the results analyzed. Results After 2 years, a significant between-group difference in posterior capsule opacification (PCO) but not in anterior capsule alterations was observed. Behind all CeeOn 911F sharp-edge IOLs, the capsule remained clear; in 2 of 23 capsules behind the CeeOn 920 rounded-edge, a neodymium: YAG laser capsulotomy had to be performed for dense central fibrotic PCO. Seven of 21 of the remaining eyes had first-degree central fibrotic PCO, 14 of 23 had peripheral mixed fibrotic and slender Elschnig pearl PCO, and 8 of 23 had second-degree peripheral PCO. Specular microscopic findings did not differ between the 2 groups. No severe IOL decentration occurred in any eye; 25% in the sharp-edge group and 40% in the rounded-edge group had minimal decentration. Conclusion The silicone IOL with the sharp optic edge design was associated with significantly reduced PCO 2 years postoperatively.

Iridocorneal Endothelial Syndrome with Contralateral Guttate Endothelial Dystrophy: A Light and Electron Microscopic Study

Both eyes from a 75-year-old woman who had unilateral closedangle glaucoma, characteristic endothelial specular microscopic findings, and slowly progressive tractional iris abnormalities consistent with essential iris atrophy were obtained postmortem and studied by light, scanning, and transmission electron microscopy. Clinically, the nonglaucomatous right eye had an open-angle, normal iris, and severe endothelial dystrophy with three-plus corneal guttae. In this eye, results of histopathologic examination disclosed marked endothelial degeneration and typical guttate excrescences on Descemet's membrane. In contrast, the endothelium in the fellow eye with the essential iris atrophy variant of the iridocorneal endothelial (ICE) syndrome was strikingly different. The endothelial cells were relatively well preserved and exhibited marked pleomorphism, anisocytosis, and flat, occasionally paired oval nuclei. Binucleate cells also were observed. The endothelial monolayer had secreted a new layer of fibrillar extracellular matrix material on the posterior surface of Descemet's membrane. Extracellular matrix material was found interposed between the iris and cornea in zones of synechial closure, and an endothelial membrane was present on the anterior surface of the iris. These observations support the hypothesis that the iris abnormalities in essential iris atrophy are secondary to endothelial proliferation. The endothelial cells displayed neither tonofilaments nor abundant apical microvilli. The latter observation suggests that increased numbers of endothelial microvilli are not responsible for the characteristic specular microscopic picture seen in the ICE syndrome.

Intraocular pressure and the corneal endothelium after neodymium-YAG laser posterior capsulotomy. Relative effects of aphakia and pseudophakia.

We studied intraocular pressure (IOP) changes and specular microscopic findings in 118 consecutive neodymium-YAG laser posterior capsulotomy procedures; 37 cases were aphakic, and 81 were pseudophakic. There was a significantly greater rise in IOP one hour after Nd-YAG laser treatment in the aphakic group than in the pseudophakic group (8.2 mm Hg vs 3.5 mm Hg, respectively). At one week postoperatively, IOPs in the aphakic group were still significantly elevated over baseline levels (3.6 mm Hg), while those in the pseudophakic group had returned to baseline levels. Differences in treatment between the aphakic and pseudophakic groups in total number of pulses, average energy, and total energy did not explain the differences in IOP. No significant change in endothelial cell densities was seen between pretreatment measurements and those taken one week after Nd-YAG laser treatment.