Silay Canturk Ugurbas

The course of corneal and intraocular pressure changes during pregnancy

OBJECTIVE To determine concurrent changes in corneal thickness, intraocular pressure (IOP), and corneal topography measurements during normal pregnancy. DESIGN Prospective cohort study. PARTICIPANTS We studied 50 eyes from 25 healthy women whose ages ranged from 21 to 35 years and who were first seen during the 10th week of pregnancy. METHODS Measurements included IOP (noncontact tonometry); corneal thickness (ultrasound pachymetry); and corneal topography (TMS 2N, TOMEY, Nagoya, Japan). Changes in IOP, central corneal thickness (CCT), and corneal power were calculated at 4 time periods: first trimester, second trimester, third trimester, and 3 months postpartum. RESULTS The mean IOPs in the second and third trimesters of pregnancy were found to be lower than those in the first trimester and at 3 months postpartum (p = 0.001). The mean CCT in the second and third trimester of pregnancy was measured to be higher than in the first trimester and at 3 months postpartum (p < 0.001). Both IOP and CCT returned to first-trimester levels following delivery. In the third trimester, a 3.1% increase in CCT was associated with a 9.5 % decrease in IOP. Topographic measurements did not show statistically significant changes throughout the trimesters or after pregnancy. CONCLUSIONS An increase in CCT was accompanied by a decrease in IOP in the second and third trimesters. Physiologic changes occurring in CCT and IOP should be considered in the management of glaucoma during pregnancy.

Tear Film Osmolarity in Patients with Diabetes Mellitus

Purpose: To compare tear film osmolarity (TFO) between patients with diabetes mellitus (DM) and normal healthy individuals. Methods: In this prospective case-controlled study, the TFO in 46 normal subjects (control group) and 55 patients with DM (study group) was evaluated. TFO in milliosmole (mOsm) was measured by using an auto-osmometer. The serum levels of glycosylated hemoglobin (HbA1c) and blood glucose in all participants were also measured. Mean outcome measures were TFO and its relationship with HbA1c level and duration of DM. Results: Mean TFO was 320.40 ± 21.80 mOsm/l in the study group and 308.22 ± 18.16 mOsm/l in the control group (p < 0.001). The TFO values were significantly associated with duration of DM (r = 0.476, p < 0.001), but no significant correlation was found with HbA1c level (r = 0.225, p = 0.114). Conclusions: The study shows a significantly higher TFO in patients with DM than in the healthy controls. TFO also correlates with the duration of DM.

Validation of plusoptiX S04 photoscreener as a vision screening tool in children with intellectual disability

PURPOSE Intellectual disability (ID) is a major public health issue, affecting more than 1% of children worldwide. Pediatric vision screening using standard eye charts may be challenging for children with ID, who may benefit from a quick noninvasive vision screening tool. This study evaluated the accuracy of plusoptiX S04 (Plusoptix Gmbh, Nuremberg, Germany) in detecting amblyopia risk factors in children with ID. METHODS Children diagnosed with ID according to age-appropriate psychological tests were examined consecutively. Vision screening was performed using the plusoptiX S04 prior to complete ophthalmological examination, including cycloplegic refraction. Pass/refer screening results was compared with findings of ophthalmological examination. Amblyogenic risk factors were defined according to American Association for Pediatric Ophthalmology and Strabismus referral criteria. RESULTS A total of 182 infants and children were examined. Only 3% of children were uncooperative for screening. Ophthalmological examination detected amblyogenic risk factors in 32% of patients. The sensitivity of plusoptiX S04 was 95% (95% CI, 85.6%-98.9%), and specificity was 50% (95% CI, 40.8%-59.1%). The positive predictive value was 47% (95% CI, 37.7%-56.4%) and the negative predictive value was 95.4% (95% CI, 87.1%-99.1%). CONCLUSIONS High sensitivity and negative predictive values suggest that the plusoptiX S04 will detect most children with ID who have amblyogenic risk factors, but one-half of all children referred will have no risk factors.

The local vasoconstriction of infant's skin following instillation of mydriatic eye drops

BackgroundSystemic absorption of eye drops is known to occur via the nasal mucosa, cornea, and conjunctiva. Diffusion of eye drops through the skin is previously unrecognized. Here, two cases are presented in which we observed skin pallor around the eyes after instillation of phenylephrine 2.5% drops. Case 1 A 32-week gestational age premature infant had mydriatic eye drops instilled as part of retinopathy of prematurity screening. Case 2 A term newborn dysmorphic infant underwent fundus examination to rule out ocular pathology. In both cases, discoloration of periorbital skin was observed 45 min following administration of drops.ConclusionThe risks of percutaneous toxicity must always be considered in children, especially in premature neonates, in whom the epidermal permeability barrier is frequently incompetent. Application of smaller drop size or wiping of overflowed drop from the skin may be useful to decrease the risk of systemic side effects.

Effects of a new hemostatic agent Ankaferd Blood Stopper® on the intraocular tissues in rat model

Purpose: To investigate the histopathological changes due to administration of Ankaferd Blood Stopper® (ABS) into intraocular tissues by an anterior chamber and intravitreal injections. Methods: Twenty Wistar albino rats were divided into four equal groups. Group 1 was injected 0.01 mL ABS into anterior chamber. Group 2 was injected intravitreal 0.02 mL ABS. Groups 3 and 4, which were used as controls, were injected into the anterior chamber and intravitreal 0.01 mL and 0.02 mL balanced salt solution (BSS), respectively. At 2, 5, 10, 15 and 20 days after injection, the eyes were examined under an operating microscope and were subsequently enucleated for histopathological examination. Results: Ophthalmic examination of the rats prior to enucleation revealed ocular complications ranging from conjunctival hyperemia to corneal perforation in group 1 and increased conjunctival hyperemia and discharge in group 2. No physical and histopathological anomalies were detected in groups 3 and 4. All eyes in group 1 showed mixed type inflammatory cell reaction, foreign-body reaction, stromal congestion, disintegration of the collagen fibers and loss of the epithelium of the posterior wall in the iris and ciliary body were observed histopathologically. All eyes in group 2 showed disintegration and separation of the retina, brown pigment accumulation and mixed type inflammatory cell reaction. Conclusion: Our results indicate that the commercially available form of ABS solution exerts a toxic effect on intraocular tissues. We consider that the intraocular use of different concentrations, rather than multiple time point of ABS should be investigated.

Effects of the folk medicinal plant extract Ankaferd Blood Stopper® on the ocular surface

Purpose: To investigate the effects of Ankaferd Blood Stopper® (ABS) on the ocular surface. Methods: Twenty adult male Wistar albino rats, weighing 390–530 g, were used in this prospective, controlled trial. One drop of ABS and one drop of balanced salt solution (BSS) were instilled into the lower conjunctival sac of the right and left eyes, respectively. After the rats were anesthetized, the ocular surface was evaluated based on the Draize criteria, and fluorescein tests were performed at 1, 2, 4, 18, 24, and 48 h. Subsequently, the rats were killed and all eyes were enucleated for histopathological examination. Results: The outcome of the Draize and fluorescein tests revealed that ABS caused more irritation of the ocular surface than BSS (P < 0.001). The highest mean ABS score was 4.9 for the Draize test and 0.4 for the fluorescein test, and ABS was considered to be a slight irritant. Histopathological examinations of the cornea and the conjunctiva revealed no significant difference between the eyes instilled with BSS and those instilled with ABS. Conclusions: ABS is a hemostatic drug that exerts a slight toxic effect on the ocular surface. Given its ease of use and antibacterial activity, as well as its efficiency in stopping bleeding, the use of ABS during ocular surgery should be further investigated in experimental and clinical studies.

Tear function and ocular surface after Muller muscle-conjunctival resection.

Muller muscle-conjunctival resection (MCR) is a surgical technique to correct mild and moderate ptosis. In this study, tear function tests and ocular surface are evaluated in patients who underwent unilateral surgery. Sixteen patients with normal preoperative tear function who underwent unilateral MCR were evaluated prospectively. The fellow eyes of the patients were taken as the control group. A dry eye assessment questionnaire, Schirmer testing, tear film break-up time, fluorescein stain, Rose-Bengal stain, and conjunctival impression cytology were used to assess the tear film functions and ocular surface changes in the operated and non-operated eyes. There was no statistically significant difference in the tear function tests and goblet cell densities between the operated and non-operated eyes. The results indicate that an MCR procedure has no apparent effect on tear function tests and goblet cell density in patients with normal preoperative tear function.

Use of a novel haemostatic agent: ankaferd blood stopper in conjunctival incisions

Background:  To investigate the haemostatic efficacy and histopathological effects of a new haemostatic agent, ankaferd blood stopper, in a rat conjunctival incision model.

The Effect of Dexamethasone Intravitreal Implant on Retinal Nerve Fiber Layer in Patients Diagnosed with Branch Retinal Vein Occlusion

ABSTRACT Purpose: To evaluate the effect of a single dose of intravitreal dexamethasone (DEX) implant on retinal nerve fiber layer (RNFL) thickness in patients with branch retinal vein occlusion (BRVO) in a 6-month period. Materials and methods: This retrospective observational study included the patients with BRVO who received intravitreal DEX implant and whose assessment included the baseline RNFL thickness measurements. The data of 26 eyes of 24 patients were retrospectively analyzed. Spectral domain optic coherence tomography was used to measure peripapillary RNFL thickness in six regional subfields. Intraocular pressure (IOP) values at each visit were recorded. The data of single dose DEX implant during 6 months were assessed. Results: The mean preoperative and postoperative 6th month nasal RNFL values were 85.4 ± 23.0 μm and 82.1 ± 17.6 μm, respectively, and the difference between the measurements was not statistically significant (p = 0.372). There was a slight decrease in the mean RNFL values postoperatively compared to the baseline values in all quadrants except supero-temporal quadrant; however, none of them reached statistically significant level (p > 0.05). The mean IOP values before and 6 months after implantation were 15.7 ± 2.9 mmHg and 16.5 ± 4.2 mmHg, respectively. The difference between the 6th month IOP values and baseline IOP values was not statistically significant (p = 0.236). Conclusion: Intravitreal DEX implant seems to have no adverse effect on RNFL thickness in BRVO patients in a 6-month period.

Ophthalmomyiasis externa: three cases caused by Oestrus ovis larvae in Turkey

Ocular involvement of parasitic infections includes external, internal and orbital ophthalmomyiasis. Oestrus ovis (sheep botfly) is the most common cause of ophthalmomyiasis externa. Living in warm climates, particularly in agricultural districts, is a risk factor. Although external ophthalmomyiasis can be treated by removal of the infecting larva(e) and topical drug treatment, the risk remains of its presence leading to further contamination for other people. We describe three cases of external ophthalmomyiasis due to infestation with the first instar larvae of O. ovis An awareness of larval conjunctivitis in endemic areas may avoid misdiagnosis and allow immediate management to prevent complications.