Ocular surface characteristics in acne vulgaris.

Clinical relevance: Since acne vulgaris is a disease of the sebaceous glands, it may have potential effects on the ocular surface and tear homoeostasis, which are essential for good vision. Optometrists should be aware of ocular surface pathologies when prescribing glasses or contact lenses for the visual rehabilitation of these young patients.Background: To evaluate the ocular surface features, meibomian glands, and tear parameters of patients with acne vulgaris.Methods: The right eyes of 70 individuals (34 patients with acne vulgaris, 36 healthy volunteers) were evaluated. The tear break-up time of participants was measured, and the Schirmer test was performed. Then, to determine ocular surface characteristics, samples were taken from the conjunctiva for impression cytology. Finally, the loss rates of the upper and lower eyelid meibomian glands were determined by taking meibography (Sirius, CSO, Florence, Italy).Results: Tear break-up time was significantly lower in the study group compared to the control group (p < 0.001). No statistically significant difference was determined between the groups in respect of Nelson grade in the conjunctival impression cytology (p = 0.141). Grade 3 cytological changes were not observed in either group. The median value of the loss rate in the meibomian glands in the upper eyelid of patients with acne vulgaris was 19.10% (IQR: 18%), while it was 8.75% (IQR: 9.53%) in the control group (p = 0.001). The median value of the loss rate in the meibomian glands in the lower eyelid was 15.70% (IQR: 15.13%) and 7.70% (IQR: 6.53%) in the acne vulgaris and control groups, respectively (p < 0.001).Conclusion: Our study shows that patients with acne vulgaris may have a predisposition to meibomian gland damage and tear instability. Therefore, we consider that a more detailed ophthalmologic examination should be performed in patients with acne vulgaris.

Ability of non-invasive tear break-up time to determine tear instability in contact lens wearers.

PURPOSE: To evaluate the performance of precorneal and prelens non-invasive tear break-up time (NIBUT) measurements to determine tear instability in contact lens (CL) wearers. METHODS: In this study, 50 eyes of 25 CL wearers were evaluated. Precorneal first and average NIBUTs and fluorescein tear break-up time (FBUT) were measured before wearing CLs in the morning. Those with FBUT less than 10 s were considered to have tear instability. After wearing CL, first and average prelens NIBUTs were measured at the 30th minute. The receiver operating characteristic (ROC) curve was analyzed to evaluate the performance of NIBUT measurements in the diagnosis of tear instability. RESULTS: The FBUT value had a significant correlation with first and average precorneal NIBUT values (p < 0.001, r = 0.653 and p < 0.001, r = 0.628, respectively). The FBUT value had no correlation with the prelens first and average NIBUT values (p = 0.542 and p = 0.263, respectively). To understand the relationship between the precorneal and prelens NIBUT values measured by the automated method, their correlation was evaluated. There was no significant correlation between the precorneal and prelens NIBUTs (for all; p > 0.05). The area under curve (AUC) in ROC curve for the first and average precorneal NIBUTs were 0.842 (p < 0.001) and 0.810 (p < 0.001), respectively. The AUC values for the first and average prelens NIBUTs at the 30th minute of CL wear were 0.586 and 0.619, respectively (p = 0.317 and p = 0.166, respectively). CONCLUSIONS: Precorneal NIBUT measurements may be useful in diagnosing tear instability. Prelens NIBUT values are not yet capable of adequately defining the tear film dynamics in CL wearers.

Performance of a photoscreener in detecting accommodation spasm.

CLINICAL RELEVANCE: For a correct spectacle prescription, accommodation spasm should not be overlooked in the measurements made using an autorefractometer. Although this can be easily understood with cycloplegia, it is not practical. Therefore, investigating practical methods that can predict excess accommodation will be useful in clinical practice. BACKGROUND: To evaluate the performance of a photoscreener in detecting pseudo-myopia due to accommodation spasm and whether it eliminates the need for cycloplegia. METHODS: Study was conducted in Van Training and Research Hospital. The manifest refraction of the patients was measured using an by an autorefractometer followed by a photoscreener before cycloplegia. Cycloplegic refraction errors were detected using an autorefractometer. Patients with pseudo-myopia due to accommodation spasm were diagnosed by observing a significant hyperopic shift in cycloplegic autorefractometer values compared to the non-cycloplegic values and were included in study. Cycloplegic autorefractometer and non-cycloplegic photoscreener measurements were compared. RESULTS: The mean non-cycloplegic autorefractometer values were as follows: --6.34 ± 1.29D, -0.42 ± 0.58D, and -6.55 ± 1.36D for spherical, cylindrical, and spherical equivalents, respectively. These values were 0.23 ± 0.63D, -0.21 ± 0.41D, and 0.11 ± 0.73D for cycloplegic autorefractometer measurements, respectively. Cycloplegic autorefractometer values showed a significant hyperopic shift of 6.57 ± 1.26D and 6.67 ± 1.34D for spherical and spherical equivalents, respectively, compared to non-cycloplegic values (p < 0.001 for both). There was no significant difference between non-cycloplegic photoscreener and cycloplegic autorefractometer measurements for spherical, cylindrical, and spherical equivalents (p = 0.126, p = 0.078, and p = 0.053, respectively). . There was agreement between the measurements in the Bland-Altman graph. CONCLUSION: There was consistency between non-cycloplegic photoscreener and cycloplegic autorefractometer measurements in patients with pseudomyopia due to accommodation spasm. Therefore, photoscreener measurements can be a fast, practical, cost-effective examination method for screening these patients without the need for cycloplegia.

Static and dynamic pupillary characteristics in multiple sclerosis.

PURPOSE: To examine the static and dynamic pupillary functions with automated pupillography in multiple sclerosis (MS) patients with preserved visual acuity. METHODS: Forty-seven MS patients with preserved visual acuity were included in the study group and 43 healthy volunteers in the control group. The visual evoked potential of the patients was obtained. After routine ophthalmologic examination contrast sensitivity and the retinal nerve fiber layer (RNFL) thickness were measured. Finally scotopic, mesopic, and photopic pupillographies followed by dynamic pupillography were undertaken, and the pupillary dilatation speed was calculated. RESULTS: The contrast sensitivity and RNFL thickness of the MS group were significantly lower than those of the control group (p < 0.05; for both). In the MS and control groups, the scotopic pupil diameters were 5.48 ± 1.03 and 5.28 ± 0.78 mm, mesopic pupil diameters were 4.82 ± 0.83 and 4.48 ± 0.70 mm, and photopic pupil diameters were 3.84 ± 0.79 and 3.42 ± 0.49 mm, respectively (p = 0.315, p = 0.044, and p = 0.004, respectively). In dynamic pupillography, the pupil in the MS group was more dilated than control group at all time sections examined except the sixth second (p < 0.05; for all). Although the mean pupillary dilation speed in the first second was higher in the MS group (p = 0.044), there was no significant difference between the groups for the other time intervals examined (p > 0.05; for all). There was no correlation between pupillary parameters and P100-wave latency, RNFL thickness, or contrast sensitivity (p > 0.05; for all). CONCLUSIONS: Static and dynamic pupillary functions may be affected in MS patients with preserved visual acuity. Although scotopic pupillary functions are preserved, mesopic, and photopic pupil functions are weakened.

Impression cytology and meibomian glands in conjunctivochalasis.

PURPOSE: To evaluate the tear parameters, meibomian glands and lid margin and tarsal conjunctival impression cytology in patients with conjunctivochalasis (CCH). METHODS: The study included 57 patients diagnosed with CCH and 35 healthy volunteers. Tear break-up time (TBUT) was measured and Schirmer test was performed. Meibomian gland morphologies, dropout rates, and meiboscores were evaluated using meibography. Finally, impression cytology samples were taken by pressing the impression filters on the lower lid margin and lower tarsal conjunctiva. The samples were evaluated according to the Nelson grading system. RESULTS: Schirmer test was longer and TBUT was shorter in the study group (p = 0.035 and p < 0.001, respectively). The median of meibomian gland dropout rate was 33.45% (Interquartile range [IQR]; 23.17%-49.75%) and 18.80% (IQR; 12.35%-26.50%) in the study and control groups, respectively (p < 0.001). There was no significant difference in terms of lid-margin cytology between the two groups (p = 0.481). In tarsal conjunctiva cytology, the median value of Nelson grade of the study group was 2 (IQR; 1-2) and that of the control group was 1 (IQR; 1-2) (p = 0.040). When Nelson grade-2 and above was accepted as the pathological limit, it was found that 27.5% of the study group and 15.2% of the control group showed pathological findings (p = 0.204). CONCLUSIONS: In patients with CCH, damage occurs in the tarsal conjunctiva with the effects of redundant conjunctival folds. In these patients, atrophy occurs in the meibomian glands and tear stability is impaired. Therefore, CCH should not be overlooked in clinical practice.

Nasal mucociliary clearance and hearing loss in pseudoexfoliation syndrome.

PURPOSE: To evaluate nasal mucociliary clearance (NMC) and hearing loss in patients with pseudoexfoliation (PEX) syndrome. METHODS: The study included 36 patients with PEX syndrome as the study group, and 39 healthy individuals as the control group. The duration of NMC was measured using the saccharine test. Audiometry was applied at 250, 500, 1000, 2000, 4000, 6000 and 8000 Hz frequencies to determine hearing thresholds and prevalence of hearing loss. RESULTS: No statistically significant difference was determined between the groups in respect of age and gender (p = 0.23 and p = 0.36, respectively). In the saccharine test, the mean NMC time was 18.41 ± 8.53 min for the study group and 11.69 ± 4.96 min for the control group. The mean NMC time of study group was significantly longer than that of the controls (p < 0.001). In the comparisons of the two groups in terms of the prevalence of hearing loss, no statistically significant difference was found at any of the evaluated frequencies (p > 0.05, for all). There was also no statically significant difference between groups in relation to hearing thresholds at these frequencies (p > 0.05, for all). CONCLUSION: The NMC time was significantly prolonged in patients with PEX syndrome. This result indicates that nasal mucosa cilia, which have similar elastic and mobile structures as the iris, are damaged in PEX syndrome, which is an infiltrative disease increasing the rigidity of affected tissues. In upper respiratory tract infections of unknown cause, PEX syndrome should be considered among the etiological factors. In this study, no significant relationship was detected between PEX and hearing loss.

Can the CRP/albumin Ratio be Used as a New Indicator of Activation in Patients with Uveitis?

Purpose: To evaluate whether the C-reactive protein (CRP)/albumin ratio (CAR) in patients with uveitis during an attack is a marker that can give information about the activity, severity and prognosis of the disease.Methods: This study included 35 patients with an uveitis attack and 35 healthy volunteers. The localization and severity of uveitis were recorded. Patients' complete blood count (CBC) during the attack, CRP, CAR, erythrocyte sedimentation rate(ESR), neutrophil/lymphocyte ratio(NLR), and platelet/lymphocyte ratio(PLR) were recorded.Results: The mean age was 34.1 ± 12.5 years for the 35 uveitis cases and 30.1 ± 4.1 years for the healthy volunteers. CRP and CAR were significantly higher in uveitis patients (p = .015 and 0.011, respectively). While CRP and CAR were significantly higher in severe anterior uveitis than mild anterior uveitis (p = .036 and 0.022, respectively), only CAR was significantly higher in severe posterior and panuveitis than mild ones(p = .017).Conclusion: CAR may be an important parameter in determining the activation of the uveitis.

The Relationship of the Urotensin-2 Level in the Aqueous Humor with Systemic Diseases and Pupil Size: Comparative Study.

Purpose: To detect the presence of urotensin-2 (U-II) in the aqueous humor and evaluate the relationship between aqueous humor level and systemic diseases and pupil size. Methods: The study included 88 patients who underwent cataract surgery. Those with a pupil diameter (PD) of up to 4 mm were considered to have small dilation, those with 4-7 mm of dilatation were considered to have moderate dilation, and those with a PD of more than 7 mm considered to have large dilation. Patients with HT (hypertension) were classified as group 1, those with DM (diabetes mellitus) as group 2, and those with HT+DM as group 3, and those without any systemic disease as group 4. The U-II levels in humor aqueous samples taken from anterior chamber were measured. Results: When compared with the control group, it was observed that the level of U-II in the aqueous humor of the HT, DM, and DM+HT groups was significantly higher (P < 0.05). At the same time, when we compared the DM+HT group with the other groups, the level of U-II in the aqueous humor was significantly higher compared to the group with DM (P < 0.05). The U-II levels of the aqueous humor were higher in the patients with small pupils compared to the remaining groups (P < 0.005). Conclusion: U-II may play a role in small pupil pathophysiology. In addition, it was determined that patients with HT and/or diabetes had higher U-II levels in the aqueous humor than healthy individuals.

Ocular Surface and Conjunctival Cytology Findings in Patients With Confirmed COVID-19.

PURPOSE: To assess the effect of severe acute respiratory syndrome coronavirus-2 infection on the conjunctiva and tear film. METHODS: Thirty-eight patients with confirmed COVID-19 and 31 healthy controls were included in this prospective and observational study. Individuals with COVID-19 formed the patient group, and healthy individuals formed the control group. Conjunctival impression cytology (CIC), TBUT, Schirmer II test, and ocular surface disease index were evaluated in all participants. RESULTS: No significant difference was observed regarding the mean age and gender between the groups (P=0.786 and P=0.122, respectively). The mean TBUT and Schirmer II test results did not differ between the two groups (P=0.496 and P=0.447, respectively). The CIC results revealed decreased density and cell size of goblet cells and moderate to high enlargement, squamous changes, and increased nucleocytoplasmic ratio in nongoblet epithelial cells in the COVID-19 group compared with the control group. Based on the Nelson classification in CIC samples, 60.6% of the COVID-19 group and 19.4% of the control group had changes consistent with grade 2 or above. The presence of neutrophils in CIC was significantly higher in the COVID-19 group (P<0.001), whereas the presence of lymphocyte was similar between the two groups (P=0.247). CONCLUSION: This study revealed the pathological conjunctival alterations in patients with COVID-19 and demonstrated that pathological ocular surface alterations may present even at the beginning of COVID-19 without clinically significant ocular manifestation.

A New Treatment Experience in Pseudomonas Keratitis: Topical Meropenem and Cefepime.

PURPOSE: To compare the efficacy of topical meropenem and cefepime treatments with respect to moxifloxacin as new treatment options in an experimental Pseudomonas keratitis model. METHODS: Twenty-four rabbits in which keratitis are induced using Pseudomonas aeruginosa were divided into four groups according to treatment options. A solution of 50 mg/mL meropenem was prepared and topically applied to the first group, 50 mg/mL cefepime solution to the second group, topical 0.5% moxifloxacin drop to the third group, and topical isotonic (0.9% saline) solution to the fourth (control) group. The eyes were examined before and after treatment to score the clinical severity. After the subjects were sacrificed, their corneas were excised. To determine the efficacy of treatments, clinical score, bacterial load, and histopathological and immunohistochemical findings were evaluated. RESULTS: When the three treatment groups were compared, there was a significant difference in the colony-forming unit (CFU) value, polymorph-nuclear leukocyte (PMNL) infiltration, and matrix metalloproteinase (MMP)-9 immunoreactivity (P=0.022, P=0.038, and P=0.037, respectively). The CFU values, PMNL infiltration scores and MMP-9 immunoreactivity were significantly lower in the meropenem and moxifloxacin groups compared with the cefepime group (P<0.05 for all). There was no significant difference between the meropenem and moxifloxacin groups in respect of the CFU values, PMNL infiltration, and MMP-9 immunoreactivity (P=0.842, P=0.784, and P=0.699, respectively). CONCLUSION: The results of our study indicate that topical meropenem is at least as effective as topical moxifloxacin in the treatment of Pseudomonas keratitis. The meropenem and moxifloxacin are safer and suitable in the limited corneal invasion than cefepime. Thus, topical meropenem may be an alternative drug in the treatment of this condition. Clinical studies are needed to be conducted to assess this possibility more accurately.

Evaluation of Meibomian Glands in Obstructive Sleep Apnea-Hypopnea Syndrome.

PURPOSE: To evaluate the effect of obstructive sleep apnea-hypopnea syndrome (OSAHS) on the meibomian glands, ocular surface, and tear parameters. METHODS: The study included 59 individuals (32 subjects with OSAHS, 27 control subjects) who underwent polysomnography in the Chest Diseases Clinic. The right eyes of all individuals were evaluated in the Ophthalmology Clinic. The first noninvasive tear break-up time (f-NTBUT) and the average noninvasive tear break-up time were measured, and Schirmer test was applied. Meibography was taken (Sirius; CSO, Florence, Italy), and meiboscore was used for indexing meibography. Finally, a sample was taken for conjunctival impression cytology. RESULTS: In the study and control groups, the median of f-NTBUT was 2.1 seconds [interquartile range (IQR); 1.5-5.0] and 5.7 seconds (IQR; 2.9-8.8) and the median of average noninvasive tear break-up time was 5.6 seconds (IQR; 3.6-9.5) and 7.2 seconds (IQR; 4.2-10.7), respectively (P = 0.007 and P = 0.487, respectively). The mean Schirmer value was 16.3 ± 5.9 mm (range; 5-25) and 17.3 ± 6.6 mm (range; 5-30) in the study and control groups (P = 0.604). In upper eyelid meibography, the median of loss in the meibomian glands was 20.10% (IQR; 11.60%-40.80%) in the study group and 14.70% (IQR; 10.40%-21.30%) in the control group (P = 0.043). In lower eyelid meibography, the median of loss in the meibomian glands was 19.00% (IQR; 13.60%-35.30%) in the study group and 12.40% (IQR; 9.10%-16.40%) in the control group (P = 0.002). The median of the Nelson grade in conjunctival impression cytology was 1 (IQR; 0-1) in the study group and 1 (IQR; 0-1) in the control group (P = 0.445). CONCLUSIONS: The loss in the meibomian glands together with the shortened f-NTBUT shows that there could be a predisposition in OSAHS for evaporative dry eye originating from meibomian gland damage.

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.

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.

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 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.

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.