VOLUME 77 - ISSUE 6

Purpose: To compare the results of central corneal thickness (CCT) measurements obtained using optical low-coherence reflectometry (OLCR), Fourier domain optical coherence tomography (FD-OCT), and a Scheimpflug camera (SC), combined with Placido corneal topography. Methods: A total of 25 healthy subjects were enrolled in the present study, and one eye of each subject was included. A detailed ophthalmic examination was performed in all cases following CCT measurements with OLCR, FD-OCT, and SC. The results were compared using an ANOVA test. Bland-Altman analysis was used to demonstrate agreement between methods. Intra-examiner repeatability was assessed by using intraclass correlation coefficients (ICCs). Results: Statistically significant differences were observed between the results of the CCT measurements obtained using the three different devices (p=0.009). Significant correlations were found between OLCR and FD-OCT (r=0.97; p<0.0001), FD-OCT and SC (r=0.91; p<0.0001), and OLCR and SC (r=0.95; p<0.0001). The 95% limits of agreement (LOA) obtained from Bland-Altman plots were from -7.2 μm to 28.7 μm for OLCR versus FD-OCT, from -19.2 μm to 30.4 μm for OLCR versus SC, and from -42.6 to 32.3 μm for FD-OCT versus SC. Intra-examiner repeatability was excellent for each method, with ICCs >0.98. Conclusion: Although the results of CCT measurements obtained from these three devices were highly correlated with one another and the mean differences between instruments were comparable with the reported diurnal CCT fluctuation, the measurements are not directly interchangeable in clinical practice because of the wide LOA values.

Keywords: Cornea/anatomy & histology; Corneal topography/methods; Tomography, optical coherence/methods; Fourier analysis; Comparative study; Observer variation

Purpose: To study the aerobic bacterial microbiota of the conjunctiva in diabetic patients with regard to the management of diabetes, assessed using glycated hemoglobin levels. Methods: A cross-sectional study was conducted using conjunctival smears of diabetic patients from both sexes and with different ages, residing in two different Brazilian cities (Sorocaba and Rio Branco). A control group of non-diabetic patients was also included. The diabetic patients were considered to have controlled diabetes when their glycated hemoglobin level was ≤7% and blood glucose level was ≤126 mg/dL. Patients with non-controlled diabetes were those with glycated hemoglobin levels >7% and blood glucose levels >126 mg/dL. The samples obtained were inoculated in Brain-Heart Infusion broth and in culture media for aerobic bacteria (blood and chocolate agars); bacterial growth was evaluated in a microbiology laboratory. Results: A total of 120 eyes of 120 patients were included in the present study. The percentage of cultures in which bacterial growth was observed was greater in diabetic patients, although the difference was not statistically significant (p=0.103). There was a greater trend toward bacterial growth in the conjunctiva of diabetic patients with altered fasting blood glucose. There was no difference in the frequency of bacterial growth on the conjunctiva between diabetic patients with normal or altered glycated hemoglobin levels. In Sorocaba, conjunctival bacterial growth was similar to that observed in Rio Branco. The microorganism most frequently detected in the present study was Staphylococcus epidermidis, followed by Staphylococcus aureus, Proteus mirabilis, and Escherichia coli. Conclusion: There was no difference between diabetic patients with normal or altered glycated hemoglobin levels. The microorganisms found were similar to those found in studies investigating the conjunctival bacterial flora of diabetic and non-diabetic patients.

Keywords: Conjunctiva; Microbiota; Diabetes mellitus; Hemoglobin A, glycosylated

Purpose: This study was designed to evaluate the visual and anatomical outcomes after cataract surgery in diabetic patients with different intraoperative therapeutic strategies. Methods: The research design comprised of a multicentric, retrospective, interventional study conducted at 6 centers in Argentina, Brazil, Costa Rica, Puerto Rico, Spain, and Venezuela. We included 138 diabetic patients with at least 6-month follow-up following phacoemulsification and intraocular lens implantation. Best-corrected visual acuity (BCVA) and central subfield thickness were collected at baseline and at 1-, 2-, 3-, and 6-month follow-up. Of these, 42 cases were not treated with any intraoperative coadjuvant medication (Group 1), 59 patients received intraoperative bevacizumab (Group 2) and 37 patients received intraoperative triamcinolone (4 mg/0.1 ml) (Group 3). Results: The mean logMAR [± standard deviation (SD)] BCVA improved from 0.82 (± 0.43) at baseline, to 0.14 (± 0.23) at 6-month follow-up (p<0.001) in Group 1; from 0.80 (± 0.48) to 0.54 (± 0.45) (p<0.001) in Group 2; and from 1.0 (± 0.40) to 0.46 (± 0.34) (p<0.001) in Group 3. The mean central subfield thickness increased from 263.57 µm (± 35.7) at baseline to 274.57 µm (± 48.7) at 6-month follow-up (p=0.088) in Group 1; from 316.02 µm (± 100.4) to 339.56 µm (± 145.3) (p=0.184) in Group 2; and from 259.18 µm (± 97.9) to 282.21 µm (± 87.24) (p=0.044) in Group 3. Conclusion: Diabetic patients may significantly benefit from cataract surgery. This study provides evidence to support the use of intravitreal triamcinolone or bevacizumab at the time of cataract surgery in cases with pre-existent diabetic macular edema or moderate-severe non-proliferative diabetic retinopathy.

Keywords: Diabetic retinopathy; Macular edema; Cataract extraction; Intraoperative care; Phacoemulsification; Lens implantation, intraocular; Antibodies, monoclonal; Multicenter study

Purpose: To assess the prevalence and treatment outcomes of angle-closure mechanisms other than pupillary block in a population of Brazilian patients. Methods: A retrospective chart review was conducted to evaluate patients who had undergone laser peripheral iridotomy (LPI) due to occludable angles at a single institution between July 2009 and April 2012. An occludable angle was defined as an eye in which the posterior trabecular meshwork was not visible for ≥180° on dark-room gonioscopy. Key exclusion criteria were any form of secondary glaucoma and the presence of >90° of peripheral anterior synechiae. Collected data were age, race, gender, angle-closure mechanism (based on indentation goniocopy and ultrasound biomicroscopy), intraocular pressure (IOP), number of antiglaucoma medications and subsequent management during follow-up. If both eyes were eligible, the right eye was arbitrarily selected for analysis. Results: A total of 196 eyes of 196 consecutive patients (mean age 58.3 ± 11.6 years) who underwent LPI were included. In most of the patients [86% (169 patients; 133 women and 36 men]), LPI sucessfully opened the angle. Mean IOP was reduced from 18.3 ± 6.4 mmHg to 15.4 ± 4.5 mmHg after LPI (p<0.01). Among the 27 patients with persistent occludable angles, the most common underlying mechanisms were plateau iris (56%) and lens-induced component (34%). Most of these patients (85%) were treated with argon laser peripheral iridoplasty (ALPI); approximately 90% showed non-occludable angles following the laser procedure (mean IOP reduction of 18.9%), with no significant differences between patients with plateau iris and lens-induced components (p=0.34; mean follow-up of 11.4 ± 3.6 months). Conclusion: Our findings suggest that, in this population of Brazilian patients, several eyes with angle closure were not completely treated with LPI. In the present large case series involving middle-age patients, plateau iris was the leading cause of persistent angle closure and was effectively treated with ALPI. A detailed eye examination with indentation gonioscopy should always be performed after LPI to rule out persistent angle closure due to non-pupillary block mechanisms.

Keywords: Angle closure; Non-pupillary block mechanisms; Iris diseases; Iris/pathology; Iridectomy; Treatment outcome

Purposes: To objectively evaluate the torsional effect of the superior oblique muscle-weakening surgery using the tenectomy technique proposed by Souza-Dias. Methods: The present prospective study included 10 patients (20 eyes) with horizontal strabismus, bilateral superior oblique overaction and A-pattern of 15 to 30 prism diopters who underwent superior oblique tenectomy. Objective assessment of ocular torsion was performed by retinography immediately before and one month after surgery. The amount of ocular torsion was determined by measuring the angle formed by a horizontal line drawn across the geometric center of the optic disc and a second line connecting this point to the fovea. Results: The median preoperative angle was 5.56° in the right eyes and -3.43° in the left eyes. The median postoperative angle was 1.84° in the right eyes and -3.12° in the left eyes. The angle variation was statistically significant in both eyes (p=0.012 and p=0.01, respectively). Conclusion: The present study suggests that superior oblique tenectomy has an extorter effect, decreasing the intorsion detected on overaction of this muscle.

Keywords: Strabismus; Oculomotor muscles; Torsion abnormality; Ophthalmologic surgical procedures/methods

Purpose: This study was performed to evaluate the retinal nerve fiber layer (RNFL) and peripapillary choroidal thickness in eyes with tilted optic disc in order to identify characteristic RNFL and peripapillary choroid patterns verified by optical coherence tomography (OCT). Methods: Twenty-nine eyes of 29 patients with tilted optic discs were studied with spectral-domain (SD)-OCT and compared with age and sex-matched control subjects in a prospective design. The imaging of RNFL was performed using circular scans of a diameter of 3.4 mm around the optic disc using OCT. For measurements of peripapillary choroidal thickness, the standar d protocol for RNFL assessment was performed. Results: SD-OCT indicated significantly lower superotemporal (p<0.001), superonasal (p=0.001), and global (p=0.005) RNFL thicknesses in the tilted disc group than those of the control group. Peripapillary choroid was significantly thicker at the site of the elevated rim of eyes with tilted disc (p<0.001). Conclusion: This study demonstrated a clinical characterization of the main tilted disc morphologies that may be helpful in differentiating a tilted disc from other altered disc morphologies. Further studies are recommended to study the comparison between glaucoma and tilted disc groups.

Keywords: Choroid/pathology; Nerve fibers; Tomography, optical coherence; Optic disc/abnormalities

Purpose: To evaluate whether implantation of an aspheric intraocular lens (IOL) results in reduced ocular aberrations and improved contrast sensitivity after cataract surgery and, therefore, changes on frequency-doubling technology (FDT) testing. Methods: The present prospective clinical study enrolled 25 patients with bilateral cataract (50 eyes), who randomly received either an aspheric (Akreos AO) or a spherical (Akreos Fit) IOL in one eye and the other IOL in the second eye. Assessment 12 months postoperatively included photopic and mesopic contrast sensitivity testing. Higher-order aberrations (HOAs) were computed. FDT testing was divided into four areas to evaluate the variation of the values at different points. The median values of the local pattern thresholds (median area contrast sensitivity [MACS]) obtained with that division were calculated. Results: The Akreos AO group obtained statistically significantly lower values of HOAs and spherical aberration compared with the Akreos Fit group. There was a statistically significant between-group difference in contrast sensitivity under mesopic conditions at all spatial frequencies. No statistically significant differences were observed in mean deviation and pattern standard deviation. The aspheric IOL exhibited higher MACS in all areas, although a statistically significant difference was reached only in the 20-degree field area (P=0.043). Conclusion: Aspheric IOLs significantly reduced spherical aberration and HOAs, improving mesopic contrast sensitivity. Although there was a trend toward slightly improved FDT in the aspheric IOL group, it was not statistically significant.

Keywords: Cataract; Phacoemulsification; Contrast sensitivity; Lenses, intraocular

Purpose: To quantify and compare the effects of instillation with 10% phenylephrine and digital lifting on the contralateral upper eyelid of patients with involutional bilateral blepharoptosis. Methods: The present prospective clinical study involved patients with involutional bilateral blepharoptosis who underwent two tests: 1) digital lifting of the more ptotic eyelid and observation of the effect on the contralateral eyelid and 2) instillation of two drops of 10% phenylephrine in the more ptotic eye and observation of the effect on the contralateral eyelid. Patients were filmed before and 5, 10, and 15 min after instillation, and the resulting images were analyzed to obtain eyelid measurements. The results were tested using a linear mixed-effects model. Results: A total of 27 patients, ranging from 52 to 82 years of age (mean age 68.51 ± 8.21 years), 24 (88.88%) of whom were women, were included in the present study. In eyes that received instillation, the marginal distance reflex-1 (MDR1) values increased from baseline (1.21 ± 0.60 mm) until 10 min after instillation, then remained statistically unchanged until 15 min after instillation (2.42 ± 0.90 mm). Significant differences were observed in the contralateral eye of the group that underwent digital lifting (1.51 ± 0.53 mm - 1.63 ± 0.56 mm) and in the contralateral eye of the group that underwent 10% phenylephrine instillation (1.38 ± 0.54 mm - 1.63 ± 0.56 mm); p=0.02 and p<0.01, respectively. Conclusion: In all eyes, 10% phenylephrine elevated the upper eyelid, with improved eyelid height at 10 min after instillation. Significant differences were observed in the height of the contralateral eyelid when compared before and after each intervention in each group; however, this difference was very small and nearly undetectable by conventional clinical evaluation in the digital lifting group. However, the 10% phenylephrine eye-drop test resulted in substantial changes in MDR1 values in the treated and contralateral eyes, indicating clinical and statistical efficiency.

Keywords: Blepharoptosis; Eyelids/innervations; Phenylephrine; Ophthalmic solutions; Lifting; Laws of cure in homeopathy

Purpose: To describe quantitative and qualitative features of eyes with advanced bullous keratopathy assessed using ultrasound biomicroscopy, before and after anterior stromal puncture (ASP) or amniotic membrane transplantation (AMT) procedures to relieve chronic pain. Methods: The present descriptive comparative study included 40 eyes of 40 patients with chronic intermittent pain due to bullous keratopathy who were randomly assigned to one of the two treatments (AMT or ASP). Ultrasound biomicroscopy (Humphrey, UBM 840, 50 MHz transducer, immersion technique) was used, and a questionnaire about pain intensity was completed preoperatively and postoperatively at days 90 and 180, respectively. Exclusion criteria were age<18 years, presence of concurrent infection, ocular hypertension, and absence of pain. Results: In a 180-day follow-up, the AMT group exhibited mean central corneal thickness (CCT), 899.4 µm preoperatively and 1122.5 µm postoperatively (p<0.001); mean epithelial thickness (ET), 156.4 µm preoperatively and 247.8 µm postoperatively (p<0.001); and mean stromal thickness (ST), 742.9 µm preoperatively and 826.3 µm postoperatively (p=0.005). The ASP group exhibited mean CCT, 756.7 µm preoperatively and 914.8 µm postoperatively (p<0.001); mean ET, 102.1 µm preoperatively and 245.2 µm postoperatively (p<0.001); and mean ST, 654.6 µm preoperatively and 681.5 µm postoperatively (p<0.999). Correlations between CCT and pain intensity in the AMT group (p=0.209 pre- and postoperatively) and the ASP group (p=0.157 preoperatively and p=0.426 at the 180-day follow-up) were not statistically significant. Epithelial and stromal edema, Descemet’s membrane folds, epithelial bullae, and the presence of interface fluid were frequently observed qualitative features. Conclusion: CCT increased over time in both groups. The magnitude of CCT did not correlate with pain intensity in the sample studied. The presence of interface fluid was a qualitative feature specifically found in some patients who underwent AMT.

Keywords: Corneal edema; Corneal endothelial cell loss; Corneal pachymetry; Cornea/ultrasound; Amnion/transplantation; Biological dressings; Palliative care

Purpose: The present experimental study aimed to investigate the effects of intracameral trypan blue (TB) on oxidative stress parameters and apoptosis in corneal tissue. Methods: Thirty rats were randomly assigned to three groups of 10 rats each: the sham group (Group 1); control group (Group 2); and treatment group (Group 3). The control group was administered 0.01 cc of balanced salt solution. The treatment group was administered 0.006 mg/0.01 cc of TB. The total antioxidant status (TAS) and total oxidant status (TOS) in corneal tissue and blood were measured and the oxidative stress index (OSI) was calculated. Finally, corneal tissue histopathology was evaluated using staining for caspase-3 and -8, and apoptotic activity was examined. Results: The TAS, TOS and OSI levels in the blood samples were not significantly different (p>0.05 for all). Compared with the sham and control groups, the TOS and OSI levels in corneal tissue were significantly different in the treatment group (p<0.05 for all). No significant difference was observed between the sham group and the control group (p>0.05). Immunohistochemical staining for caspase-3 and caspase-8 demonstrated higher apoptotic activity in the TB group than in the sham and control groups. Conclusion: The present study showed that intracameral TB injection is safe systematically but may be toxic to corneal tissue, as demonstrated using oxidative stress parameters and histopathological evaluation.

Keywords: Trypan blue/administration & dosage; Injections; Intraocular; Cornea; Oxidative stress; Apoptosis; Animals; Rats

We herein present a case with corneal overriding due to improper suturing of a full-thickness corneal laceration. There was a 2.5-mm difference between horizontal and vertical white-to-white measurements in the cornea. However, slit lamp examination failed to demonstrate the exact architecture of the laceration. Ultrasound biomicroscopy defined the wound edges thoroughly and confirmed the presence of corneal overriding. Six weeks after suture enhancement, the abnormal oval appearance of the cornea was absent and correct apposition of the corneal edges was seen on ultrasound biomicroscopy. Ultrasound biomicroscopy can be used in preoperative surgical planning of cases with complicated corneal lacerations. It can be used to adjust and enhance wound architecture in eyes with penetrating injury.

Keywords: Cornea/injuries; Lacerations; Eye injuries, penetrating/ultrasonography; Suture techniques; Humans; Male; Adult; Case reports

Pupil abnormalities in leprosy usually result from chronic iritis with loss of stroma, iris miosis, a sluggish reaction to light, and poor dilation in response to anticholinergic mydriatics. We report two patients with long-standing lepromatous leprosy who developed tonic pupils characterized by mydriasis, absence of reaction to light and hypersensitivity to weak cholinergic solution. Examination revealed iritis and iris atrophy. In both cases, instillation of dilute 0.1% pilocarpine caused miosis in the affected eyes. Tonic pupil occurs in many conditions, but its association with leprosy had not been previously reported.

Keywords: Tonic pupil; Mydriasis; Leprosy; Iritis; Iris/injuries; Atrophy; Case reports

We describe the case of a 23-month-old female infant with a diagnosis of hemolytic uremic syndrome (HUS) and hemorrhagic retinopathy. The patient had a past history of abdominal pain, bloody diarrhea, and acute renal failure. On ophthalmologic examination, indirect ophthalmoscopy revealed extensive areas of flame-shaped hemorrhage, cotton wool spots, macular edema and optic nerve head neovascularization in both eyes. Fluorescein angiography showed severe bilateral retinal ischemia and neovascularization leakage in disk. The patient, who had the visual acuity of 20/1000 in the right eye (OD) and 20/540 in the left eye (OS) at the first examination, was treated with panretinal photocoagulation (PRP) and presented at the end of the 6th month of follow-up improvement to 20/540 in OD and 20/270 in OS. There was also a regression of disc neovascularization, hemorrhages and macular edema. Despite intense retinal ischemia, there were no complications related to angiogenesis such as vitreous hemorrhage and/or neovascular glaucoma. We describe, in this report, the association between hemorrhagic retinopathy with features of Purtscher-like disease and HUS.

Keywords: Hemolytic uremic syndrome; Retinal hemorrhage/etiology; Fluorescein angiography; Light coagulation; Infant; Case reports

The authors report fundus autofluorescence (FAF) and spectral-domain optical coherence tomography (OCT) findings of two consecutive patients who presented with optic disk melanocytoma (ODM). A retrospective study was performed by reviewing medical records and ophthalmic imaging examinations. Optical coherence tomography findings were sloped and brightly reflective anterior tumor surface, adjacent retinal desorganization and abrupt posterior optical shadowing. Vitreous seeds were found in one patient. Fundus autofluorescence revealed outstanding hypoautofluorescence at the tumor area and isoautofluorescence at the remaining retina. Optical coherence tomography findings of the reported cases are consistent with those reported in the reviewed literature. Fundus autofluorescence has been used in the assessment of choroidal melanocytic tumors, but not yet in melanocytomas. We assume that this is the first report of these findings and believe that when its pattern has become clearly defined, fundus autofluorescence will be a useful tool to avoid misdiagnosis in suspicious cases and for follow-up.

Keywords: Melanoma/diagnosis; Optic nerve neoplasms/diagnosis; Tomography, optical coherence; Fluorescein angiography; Humans; Male; Female; Adult; Case reports

Pattern electroretinography is used to assess the function of the inner retinal layers, particularly the retinal ganglion cell layer, using a reversing checkerboard or grating pattern that maintains a constant overall mean luminance over time. A normal transient response comprises a positive component of the wave (P50) followed by a longer negative component of the wave (N95). Glaucomatous optic neuropathy causes progressive loss of retinal ganglion cells, potentially detectable as abnormalities on examination, particularly in the N95 component. Therefore, pattern electroretinography may be useful in the diagnosis and evaluation of glaucoma. The present article is an updated review of published data regarding the use of pattern electroretinography for the detection of glaucoma-induced retinal changes.

Keywords: Electroretinography; Glaucoma/diagnosis; Ocular hypertension; Intraocular pressure; Vision ocular