Comparison of Two Presbyopia-Correcting Trifocal Intraocular Lenses: A Prospective Study.

Objectives: To evaluate the clinical results of a new trifocal intraocular lens (IOL) with sinusoidal design by comparing with a traditional trifocal IOL. Materials and Methods: A total of 79 patients undergoing uneventful microincisional cataract surgery with bilateral implantation of one of two types of trifocal IOLs, the Acriva Trinova IOL (VSY) or Acrysof IQ PanOptix IOL (Alcon), were enrolled in this prospective study. Visual and refractive outcomes, contrast sensitivity (CS), and defocus curve were assessed at 3 months after surgery. Patient satisfaction and incidence of photic phenomena were also evaluated. Results: The number of patients/eyes were 48/96 in the Trinova group and 31/62 in the PanOptix group. There were no significant differences between the groups for monocular and binocular corrected/uncorrected distance or intermediate (at 60 cm) and near visual acuities (VA) postoperatively. The Trinova group had statistically significantly better intermediate VA at 80 cm than the PanOptix group (p<0.05). The CS results of both groups were within the normal limits. In the binocular defocus curve of both IOLs, we observed a peak of good VA at 0.0 diopters defocus and a useful wide range for intermediate distances. The incidence of photic phenomena in the Trinova group was lower at postoperative 1 month (p<0.05) but this difference disappeared at 3 months. A total of 47 patients (97.9%) in the Trinova group and 30 patients (96.7%) in the PanOptix group stated that they would recommend the same IOL. Conclusion: Both trifocal IOLs provide good visual quality outcomes and patient satisfaction.

Clinical correlations and impact of conjunctivochalasis in soft contact lens wearers.

PURPOSE: To evaluate the correlation between clinical tests, patient symptoms, and conjunctivochalasis in contact lens wearers and non-wearers. METHODS: This study comprised 40 eyes of 40 current soft contact lens users and 40 eyes of 40 control subjects. Cross-sectional areas of conjunctivochalasis at three locations (nasal, central, temporal) during straight and downward gazes were determined using anterior segment optical coherence tomography in all participants. Tear film break up time test and Schirmer test with anesthesia were performed and for evaluation of symptoms, the participants completed ocular surface disease index questionnaire. RESULTS: During straight gaze, the mean cross-sectional areas of conjunctivochalasis were 0.0112 ± 0.009 and 0.006 ± 0.005 mm2 at nasal, 0.0096 ± 0.007 and 0.002 ± 0.004 mm2 at central, 0.0176 ± 0.014 and 0.008 ± 0.009 mm2 at temporal in contact lens and control groups, respectively. Regardless of location and gaze direction, the mean cross-sectional conjunctivachalasis areas of the contact lens group were significantly higher than those of the controls (all, p < 0.05). Significant positive correlations between ocular surface disease index score and measured conjunctivachalasis areas (in all sites) during straight gaze and downward gaze were observed in the contact lens group (all, p < 0.05 and r > 0.450). CONCLUSION: Wearing soft contact lenses is associated with increased conjunctivochalasis areas. Anterior segment optical coherence tomography determined conjunctivochalasis area is an objective clinical measurement value that is positively correlated with patients' symptoms in soft contact lens wearers.

Evaluation of corneal endothelium using specular microscopy in patients with obstructive sleep apnea syndrome.

PURPOSE: In the present study we evaluate the corneal endothelium using specular microscopy in patients with obstructive sleep apnea syndrome (OSAS). METHODS: The study included a total of 100 patients including 35 patients with mild OSAS, 34 patients with moderate OSAS and 31 patients with severe OSAS, and the right eyes of 30 patients as a control group. Patients were examined to exclude the possibility of ocular diseases. Cellular density in the cornea epithelium (cell/mm2), corneal thickness (µ), percentage of hexagonal cells (%) and the coefficient of variation were evaluated using a specular microscope. RESULTS: Corneal thickness was significantly decreased in all OSAS groups when compared to the control group (p = 0.002), while no significant difference was identified among the OSAS groups. The corneal endothelial cell density, percentage of hexagonal cells and coefficient of variation were significantly different between the OSAS groups and the control group (p < 0.001). CONCLUSION: More significant impairments were noted in the corneal endothelium of the patients in the OSAS group than in the control group, and specular microscopy is in valuable in the follow-up and treatment of such patients.

Is ocular vascularity affected in young migraine patients? A pilot study.

OBJECTIVE: This study aimed to evaluate ocular vascularity in young adult migraine patients with visual aura and without visual aura. MATERIAL AND METHODS: The study included 30 patients with migraine with visual aura (MWVA), 30 patients with migraine without visual aura (MWOVA), and 30 healthy control subjects, all between ages ≥18 and <45. Migraine patients were applied Headache Impact Test (HIT) and Migraine Disability Assessment Scale (MIDAS). Retinal nerve fiber layer thickness and ocular vascularity of all participants were evaluated with optical coherence tomography (OCT) and OCT angiography (OCTA). RESULTS: The MWVA group had significantly lower superficial and deep foveal vascular density values compared to the control group (p = 0.039, p = 0.028, respectively). The foveal avascular zone was significantly enlarged in the MWVA group compared to the control group (p = 0.033). MWVA patients had significantly lower whole optic disc, optic disc inside, peripapillary, superior hemisphere, inferior hemisphere, superior quadrant, and temporal quadrant vascular density values compared to the control group (p < 0.05 all), while there was no significant difference in the nasal quadrant (p = 0.083). Migraine attack frequency, MIDAS, and HIT were negatively correlated with ocular vascular density values. CONCLUSION: The results of our study indicate that young adult patients with MWVA are at risk of decreased ocular vascularity and that this risk may increase with frequency and severity of migraine attacks.

Effects of chronic smoking on the meibomian glands.

PURPOSE: To evaluate the effects of chronic smoking on tear function tests and meibomian glands. METHODS: This prospective study included 40 volunteers with a long-term (> 5 years) cigarette smoking history (study group) and 43 non-smoking healthy individuals (control group). The symptoms of all the participants were scored using the Ocular Surface Disease Index (OSDI) questionnaire, and a detailed ophthalmological examination was performed including the tear breakup time (TBUT) and Schirmer test (with anaesthesia). The upper and lower lid meibomian glands were evaluated with meibography using the Sirius anterior segment analysis system (Sirius, CSO, Florence, Italy). RESULTS: The groups showed homogenous distribution in respect of age and gender (p > 0.05). The patients in the study group were determined with 22.59 ± 17.25 packet/year cigarette usage. The mean OSDI score was 36.67 ± 21.47 in the study group and 31.65 ± 15.60 in the control group (p = 0.64). The TBUT and Schirmer test values were determined as 9.65 ± 6.14 s and 8.90 ± 4.95 mm, respectively, in the study group and 11.23 ± 5.94 s and 13.08 ± 8.61 mm in the control group (p > 0.05). In the upper lid meibography, loss of 24.68 ± 16.54% was determined in the study group and 17.87 ± 7.06% in the control group (p = 0.01). No statistically significant difference was determined between the groups in respect of the lower lid meibomian gland loss: study group 14.70 ± 8.49% versus control group 12.48 ± 6.44% (p = 0.20). CONCLUSIONS: Smoking results in meibomian gland damage which may be a risk factor for dry eye. In cases of ocular surface disorders related to chronic smoking, meibomian gland damage should be taken into consideration.

Amplitude of Accommodation in Patients with Multiple Sclerosis.

Purpose: To evaluate the effect of multiple sclerosis (MS) on the amplitude of accommodation (AA) and retinal nerve fiber layer (RNFL) thickness.Materials and Methods: A total of 25 MS patients with visual-evoked potential (VEP) abnormalities (MS/+VEP Group), 25 MS patients without VEP abnormalities (MS/-VEP Group), and 25 controls (Control Group) were enrolled. Only findings from the right eye of the participants were included in the analysis. Each participant underwent a pattern-reversal visual-evoked potential (PVEP) recording, an RNFL thickness analysis by optic coherence tomography (OCT) in all quadrants, and a measurement of amplitude of accommodation (AA) with minus lens technique. The AA and the RNFL thickness were compared between the groups.Results: The mean age and sex distributions did not differ significantly across the groups (p= .788, p= .906, respectively). The mean AA was 5.36 ± 0.7 D in MS/+VEP group, 6.06 ± 1.4 D in MS/-VEP group, and 6.4 ± 0.9 D in control group (p= .002). The difference in the mean AA values between MS/+VEP and control groups were significant (p = .002). AA was significantly correlated with age, P100 latency and amplitude values in MS/+VEP group (r = -0.832, p < .001; r = -0.596, p = .002 and r = 0.498, p = .011, respectively). In a multivariable regression model, age and P100 latency were significant parameters for affecting AA in patients with MS (p < .001 and p = .001). In another multivariable regression model, age and average RNFL thickness were significant parameters for affecting AA in patients with MS (p < .001 and p = .010).Conclusions: We found that the AA was lower in MS patients with VEP abnormalities compared to age-matched healthy individuals. P100 latency was a significant parameter for predicting AA in MS/+VEP group. These results suggest that MS patients with VEP abnormalities might experience presbyopia earlier in life than people without MS, probably due to the chronic demyelination of neural pathways.

Evaluation of the Ocular Surface in Different Contact Lens Replacement Schedules.

PURPOSE: To evaluate the effects of different contact lens (CL) replacement schedules and different CL materials on the ocular surface and tear function. METHODS: Daily disposable hydrogel CLs were given to group 1 (n = 22), daily disposable silicone hydrogel CLs were given to group 2 (n = 25), and reusable silicone hydrogel CLs were given to group 3 (n = 24). Tear function tests and inflammatory cytokine [interleukin (IL)-6, IL-8, IL-17A, and matrix metalloproteinase (MMP)-9] levels were evaluated before and at 1 and 3 months after CL usage. Impression cytology was evaluated before and at 3 months after CL usage. RESULTS: At the first and third months of CL usage, a statistically significant difference was determined between the groups in the levels of IL-6, IL-8, and IL-17A in tears, with the lowest levels in group 1 and the highest levels in group 3 (all P < 0.05). At the third month of CL usage, the levels of these cytokines (in picograms/milliliter) were 6.06 ± 0.83, 78.18 ± 12.42, 61.69 ± 13.95, and 37.71 ± 5.95 in group 1 and 8.04 ± 0.89, 107.34 ± 14.40, 68.63 ± 13.72, and 46.26 ± 6.50 in group 3, respectively. A statistically significant decrease was determined over time in the Schirmer test in group 1, in only the tear breakup time in group 2, and in the tear breakup time and Schirmer test in group 3 (all P < 0.05). A statistically significant increase was determined over time in the levels of IL-6, IL-8, IL-17A, and MMP-9 in all groups. In the third month, a significant progression was observed in the Nelson grade (P < 0.05) in all groups. CONCLUSIONS: The wear of daily disposable CLs can be considered to cause less damage to the ocular surface and less increase in proinflammatory cytokine levels.

Effect of Amblyopia Treatment on Choroidal Thickness in Children with Hyperopic Anisometropic Amblyopia.

PURPOSE: To evaluate choroidal thickness (CT) in the eyes of children with hyperopic anisometropic amblyopia and to assess changes in CT during amblyopia treatment using spectral-domain optical coherence tomography (SD-OCT). METHODS: This longitudinal study, initially enrolled 40 patients, aged 3-9 years with hyperopic anisometropic amblyopia. Patients underwent treatment with refractive correction alone for 16 weeks and if needed, with refractive correction and patching treatment thereafter (6 months). CT was measured perpendicularly (from the outer edge of the hyper-reflective retinal pigment epithelium to the inner sclera) at the fovea, and 1.5-mm temporal, 3.0-mm temporal, 1.5-mm nasal, and 3.0-mm nasal to the fovea using SD-OCT in amblyopic eyes and fellow eyes during treatment and in the control subjects (n = 22). RESULTS: The baseline subfoveal CT measurement was mean 367.9 ± 54 in the amblyopic eyes, 283.9 ± 39.6 in the fellow eyes, and 267.3 ± 41.3 µm in the control eyes. Before amblyopia treatment, the subfoveal CT and CT at 1.5-mm nasal and temporal to the fovea and 3.0-mm nasal to fovea in the amblyopic eyes were significantly thicker than those of the control subjects after adjustment for refraction and axial length by multivariate ANCOVA. CT at all locations decreased significantly after treatment in the amblyopic eyes. The final measurement of subfoveal choroid and CT at 1.5-mm nasal to the fovea of the amblyopic eyes was significantly thicker than those of the control subjects after adjusting for axial length and refraction. CONCLUSIONS: The findings of this study indicate that children with hyperopic anisometropic amblyopia have significant CT alterations, and these changes partially regress after amblyopia treatment.

Effects of topical acne treatment on the ocular surface in patients with acne vulgaris.

PURPOSE: To assess the ocular side effects during topical retinoid-antibiotic combination treatment in patients with facial acne vulgaris. METHODS: Forty-three patients applying topical isotretinoin+erythromycin combination (isotrexin gel, GlaxoSmithKline) once daily for the treatment of acne vulgaris were enrolled. Full ophthalmologic examination, Schirmer test (with topical anesthesia), fluorescein break-up time (BUT), corneal fluorescein staining and tear osmolarity measurement with the TearLab system (TearLab Corporation) were carried out before and at the end of the first month of the treatment. For evaluation of symptoms participants completed the ocular surface disease index (OSDI) questionnaire at each visit. RESULTS: The mean age of the patients was 23.16±3.03 (18-30) years. Mean tear osmolarity increased significantly from 282.09±8.95 mOsm/L at baseline to 300.39±16.65 mOsm/L after the treatment (p<0.001). BUT decreased from an average of 11.93±1.12s at baseline to 6.65±3.03s at the end of the first month (p<0.001). The OSDI score worsened significantly (5.41±3.65 vs 21.53±12.95, p<0.001) and punctate epitheliopathy was seen in 51% of eyes after the treatment. The average Schirmer values were 13.09±1.90 and 12.41±2.44mm/5min before and at the end of the first month of the treatment, respectively (p=0.117). CONCLUSIONS: The findings of this study indicate that topical retinoid-antibiotic combination treatment causes significant signs and symptoms of dry eye. Patients receiving topical treatment for acne should be evaluated regularly to ensure the timely detection and treatment of pathologic signs on the ocular surface.

Evaluation of choroidal thickness changes after phacoemulsification surgery.

PURPOSE: The aim of the study was to analyze the effects of uneventful phacoemulsification surgery on choroidal thickness (CT) using spectral domain optical coherence tomography (SD-OCT). METHODS: In this prospective study, 38 eyes of 38 patients having phacoemulsification surgery were included. All patients underwent detailed ophthalmologic examination, including preoperative axial length (AXL) measurement with optical biometry and intraocular pressure (IOP) measurement preoperatively and 1 month postoperatively. The CT was measured perpendicularly at the fovea and 1.5 mm temporal, 3.0 mm temporal, 1.5 mm nasal, and 3.0 mm nasal using SD-OCT preoperatively and 1 month postoperatively. Changes in the CT after surgery and correlation of this change with age, AXL, preoperative IOP, and IOP change were evaluated. RESULTS: There was a statistically significant increase in the CT at all regions evaluated. This increment was more prominent in the nasal and subfoveal regions. The IOP decreased significantly 1 month after surgery (16.14±4.94 mmHg vs 13.91±4.86 mmHg; P<0.001). The change in IOP was correlated with the CT changes at all regions, whereas age, AXL, and preoperative IOP had no significant correlations with the changes in CT. CONCLUSION: Phacoemulsification surgery may cause significant increase in CT, which is correlated with surgery-induced IOP change in the short term. Long-term follow-up of eyes having phacoemulsification surgery may provide further insight into the effects of cataract surgery on the choroid.

Effects of osmoprotective eye drops on tear osmolarity in contact lens wearers.

OBJECTIVE: To evaluate the impact of osmoprotective eye drops on tear osmolarity and patient comfort, and to compare its efficacy with a commercially available lubricant in contact lens (CL) wearers. DESIGN: Prospective, cross-sectional study. PARTICIPANTS: Forty eyes of 20 first-time CL wearers were included. METHODS: Tear osmolarity measurements using TearLab osmolarity system were performed in each eye of subjects at 8 am, and 2, 4, and 8 h after that on the first and second days, and at 12:00 on the third day and eighth days. On the second day and afterward, all eyes were fitted Purevision 2 (Bausch & Lomb) soft CLs. Subjects instilled Optive (Allergan) osmoprotective eye drops into their 1 eye (group 1) and Refresh tears (Allergan) eye drops into their other eyes (group 2) after 2 hours of CL wear on the third day and afterward. Ocular comfort with eye drops was also assessed. RESULTS: There were no significant differences between the tear osmolarity measurements of the groups on the first day. On the second day, osmolarity significantly increased from baseline after 4 h of CL wear (p < 0.05) but returned to baseline after 8 h of CL wear (p > 0.05) in both groups. Tear osmolarity measurements of group 1 were significantly lower than those of group 2 on the third and eighth days (both p < 0.05). The mean comfort scores were significantly higher in group 1. CONCLUSIONS: Tear osmolarity increases within the first hours of CL wear, and instillation of osmoprotective eye drops prevents this increment in patients wearing CLs.

Evaluation of the chorioretinal thickness changes in Alzheimer's disease using spectral-domain optical coherence tomography.

BACKGROUND: To assess the chorioretinal thickness changes using spectral-domain optical coherence tomography (SD-OCT) and to evaluate the association between these structural changes and cognitive impairment in Alzheimer's disease (AD). DESIGN: Prospective, cross-sectional study PARTICIPANTS: Thirty-one eyes of 31 consecutive patients with AD and 30 eyes of 30 cognitively healthy age-matched control subjects were recruited METHODS: SD-OCT (RTVue-100) was used to measure the macular ganglion cell complex thickness (mGCC), outer retinal thickness (ORL), and the choroidal thickness (CT). Cognitive function was evaluated by Mini-Mental State examination (MMSE) on the same day of the optical examination. MAIN OUTCOME MEASURES: Chorioretinal thickness. RESULTS: The mGCC average, mGCC superior and mGCC inferior thicknesses of the AD group were significantly thinner than those of the controls (all, P < 0.05). No significant difference was found in the ORL thickness measurements between the two groups. Compared with control subjects, the CT measurements at all regions were significantly thinner in patients with AD than controls except CT measurement at 3.0 mm temporal to the fovea (P = 0.067). Significant correlations between the mGCC thickness measurements of the AD group and MMSE scores were observed. There was no significant correlation between the MMSE scores and the CT measurements (P > 0.05). CONCLUSIONS: Patients with AD had chorioretinal structural alterations. Retinal structural alterations were seen only in the inner layers. The reduction in mGCC thickness parameters were related to the severity of cognitive impairment in AD.

Evaluation of the macular choroidal thickness using spectral optical coherence tomography in patients with obstructive sleep apnoea syndrome.

BACKGROUND: To assess the choroidal thickness (CT) in patients with obstructive sleep apnoea syndrome (OSAS) and healthy controls. DESIGN: Prospective, cross-sectional study PARTICIPANTS: Ninety-two eyes of 92 patients with OSAS and 32 eyes of 32 aged and body mass index-matched healthy subjects were enrolled. METHODS: OSAS patients were further divided into mild, moderate and severe OSAS groups according to their apnoea hypopnea index (AHI) values. The macular CT and peripapillary retinal nerve fibre layer (RNFL) thickness measurements of the subjects were obtained using spectral domain optical coherence tomography (RTVue-100, Optovue). The CT and RNFL thickness measurements of the groups were compared, and correlations among the AHI values and these measurements were calculated. MAIN OUTCOME MEASURES: Choroidal thickness. RESULTS: There were no significant differences in subfoveal and temporal CT measurements of the groups. A pairwise comparison between the groups revealed that severe OSAS group has significantly thinner CT than mild OSAS group at 3.0 mm nasal to the fovea. Also, compared with severe OSAS group, the CT measurements at 1.5 mm and 3.0 mm nasal to the fovea were significantly thicker in control eyes (both, P < 0.05). There were weak negative correlations between the nasal CT measurements and AHI in the OSAS group (nasal 1.5 mm, P = 0.002, r = -0.358; nasal 3.0 mm, P = 0.004, r = -0.336). Compared with controls, severe OSAS group had significantly thinner nasal and superior RNFL thickness measurement. CONCLUSIONS: Sleep apnoea patients had choroidal structural alterations that may have significance on the pathophysiology of the ophthalmic disorders associated with OSAS.

Marginal keratitis after intravitreal injection of ranibizumab.

PURPOSE: To report a case of marginal keratitis that developed after intravitreal ranibizumab injection. METHODS: A 56-year-old man with diffuse diabetic macular edema received intravitreal injection of ranibizumab into his right eye. RESULTS: One day after injection, the patient presented with pain, redness, tearing, and discomfort in his right eye. Anterior segment examination of the right eye revealed subconjunctival hemorrhage, 3 corneal subepithelial peripheral infiltrates separated from the limbus by a clear zone, and mild anterior chamber reaction. Examination of the eyelids was remarkable for mild blepharitis. Fungal and bacterial cultures were negative. The condition resolved with topical corticosteroids and antibiotics. CONCLUSIONS: Intravitreal ranibizumab injection may trigger hypersensitivity reaction in the form of marginal keratitis in patients with mild blepharitis.

Comparison of central corneal thickness measurements with three new optical devices and a standard ultrasonic pachymeter.

AIM: To compare the RTVue spectral optical coherence tomography (SD-OCT), Sirius Scheimpflug-Placido topographer, Lenstar optical low coherence reflectometry (OLCR) and ultrasound pachymetry (USP) devices in terms of their agreement and repeatability of measuring central corneal thickness (CCT). METHODS: In this prospective study, 50 eyes of 50 patients were included. Three repeated measures were obtained using SD-OCT, Scheimpflug-Placido topographer and USP and five measurements were determined with the OLCR. Bland-Altman plots were used to assess agreement among the instruments, and 95% limits of agreement (LoA) for each comparison were calculated. Intra-examiner repeatability was assessed using intraclass correlation coefficients (ICCs). RESULTS: The mean CCT by SD-OCT, Scheimpflug-Placido topographer, OLCR, and USP were 525.90±34.08 µm, 525.92±34.10 µm, 530.30±35.62 µm, and 543.50±37.11 µm respectively. All 4 modalities of CCT measurements correlated closely with each other, with Pearson correlation coefficients ranging from 0.977 to 0.995. The mean differences (and upper/lower LoA) for CCT measurements were -0.05±6.77 µm (13.3/-13.3) between SD-OCT and Scheimpflug-Placido topographer, 4.38±3.79 µm (11.8/-3.1) between OLCR and SD-OCT, 4.38±6.03 µm (16.2/-7.5) between OLCR and Scheimpflug-Placido topographer, 13.20±6.46 µm (25.9/0.5) between USP and OLCR, 17.59±6.76 µm (30.8/4.3) between USP and SD-OCT, and 17.58±8.13 µm (33.5/1.6) between USP and Scheimpflug-Placido topographer. Intra-examiner repeatability was excellent for all devices with ICCs>0.98. CONCLUSION: For most practical purposes, CCT measurements with the RTVue, Sirius and Lenstar can be used interchangeably. Although highly correlated, CCT measurement differences between USP and these 3 optical instruments can be significant depending on the clinical situation.

The association of spectral-domain optical coherence tomography determined ganglion cell complex parameters and disease severity in Parkinson's disease.

PURPOSE: To evaluate the association between the retinal structural changes provided by spectral domain optical coherence tomography (SD-OCT) and disease severity in Parkinson's disease (PD). MATERIALS AND METHODS: Thirty-eight eyes of 20 patients with PD and 30 eyes of 30 healthy subjects were enrolled in this prospective study. The eyes ipsilateral (20 eyes) and contralateral (18 eyes) to the most affected body side in patients with PD were evaluated separately. SD-OCT (RTVue-100) was used to measure the macular ganglion cell complex thickness (mGCC), outer retinal thickness, and peripapillary retinal nerve fiber layer (RNFL) thickness. Disease severity was assessed using Unified Parkinson's Disease Rating Scale (UPDRS). RESULTS: The differences in the nasal RNFL (p = 0.004), average mGCC (p = 0.014), superior mGCC (p = 0.007), inferior mGCC (p = 0.03) were significant between the ipsilateral eye group and controls. The differences in the nasal RNFL (p = 0.002), and superior mGCC (p = 0.038) were statisticallly significant between the contralateral eye group and controls. Inferior and average mGCC thicknesses of ipsilateral eyes were inversely correlated with UPDRS score (p = 0.001, r = -0.678 and p = 0.009, r = -0.568, respectively). Significant inverse correlation was demonstrated between UPDRS score and inferior RNFL of both eyes ipsilateral and contralateral to the most affected body side. CONCLUSIONS: There is significant thinning in mGCC parameters of the retina in PD. The SD-OCT derived mGCC parameters may improve the detection of PD progression.

Repeatability of aberrometric measurements in normal and keratoconus eyes using a new Scheimpflug-Placido topographer.

PURPOSE: To evaluate the repeatability of the anterior and posterior corneal wavefront aberrations using the Sirius Scheimpflug-Placido topographer in normal eyes and keratoconus eyes. SETTING: Bozok University Faculty of Medicine, Yozgat, Turkey. DESIGN: Evaluation of diagnostic test. METHODS: In eyes of healthy subjects and eyes of keratoconus patients, 3 repeated measurements were obtained using the Scheimpflug-Placido topographer. Repeatability of the corneal aberrometric data using a 7th-order Zernike expansion (6.0 mm pupil) and central corneal power (3.0 mm zone) in the anterior and posterior corneal surfaces were analyzed. The within-subject standard deviation (Sw) and the intraclass correlation coefficient (ICC) were calculated. RESULTS: For all modal pairs, the Sw was 0.08 µm or less for anterior and posterior corneal aberrations in both groups. The ICC of the anterior corneal surface ranged from 0.607 (pentafoil) to 0.988 (primary coma) in keratoconus eyes (n = 41) and from 0.568 (quadrifoil) to 0.856 (primary coma) in normal eyes (n = 30). The ICCs for posterior corneal surface aberrometry were 0.656 to 0.873 and 0.592 to 0.824, respectively. For anterior and posterior corneal curvatures, the Sw was 0.12 or lower and the ICC values were more than 0.93 in all cases except the posterior corneal surface reading at the 3.0 mm corneal area in keratoconus eyes (ICC 0.875). CONCLUSIONS: The intraexaminer repeatability of most anterior corneal aberrations with the Scheimpflug-Placido system was moderate to high in normal eyes and keratoconus eyes. The system showed moderate repeatability for the posterior corneal surface. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.