The outcomes of intravitreal C3F8 gas tamponade combined with laser photocoagulation treatment for optic disc pit maculopathy.

PURPOSE: To share the anatomical results and visual outcomes of intravitreal gas tamponade combined with laser photocoagulation treatment for optic disc pit maculopathy (ODPM). METHODS: Intravitreal gas tamponade combined with laser photocoagulation treatment was performed on six consecutive patients with ODPM. A 0.3 mL of 100% perfluoropropane (C3F8) gas was injected intravitreally. The patients were then asked to maintain prone position until the C3F8 gas disappeared. Laser photocoagulation was performed the day after the procedure. The outcomes were determined by spectral-domain optical coherence tomography and best-corrected visual acuity (BCVA). RESULTS: In the present study, visual improvement and reduction in serous macular detachment were observed in 83% of the ODPM patients. Complete retinal reattachment was achieved in 66% of the ODPM patients. In one patient, no regression was observed after the repeated treatment, and pars plana vitrectomy was performed. The final BCVA improved in five eyes and unchanged in one eye. No postoperative complications were observed during the follow-up period in any patient. CONCLUSIONS: Intravitreal C3F8 gas tamponade combined with laser photocoagulation procedure is an effective, minimally invasive, and cost-effective treatment method for ODPM.

Assessment of Ocular Surface in Patients With Ankylosing Spondylitis.

PURPOSE: To evaluate the clinical findings and ocular surface changes in patients with ankylosing spondylitis (AS). METHODS: This prospective study involved 45 patients with AS (group 1) and 28 healthy subjects (group 2). Patients in group 1 were in the inactive period. The study subjects underwent a complete ophthalmic examination. The right eyes of the subjects in each group were tested for the study including slit-lamp examination, Schirmer I test, tear break-up time (TBUT), conjunctival impression cytology (CIC), and ocular surface disease index (OSDI). Results between the two groups were compared. RESULTS: The mean Schirmer I test result was found as 12.2±8 mm in group 1 and 20.3±9.9 mm in group 2 (P<0.001), whereas the mean TBUT value was found as 3.8±1.9 sec in group 1 and 10.1±4.8 sec in group 2 (P<0.001). The OSDI scores were significantly higher in group 1 (36.5±19.4) than in group 2 (9.1±12.9, P<0.001). The CIC scores were significantly higher in group 1 (2.12±0.7) than in group 2 (0.57±0.6, P<0.001). Notably, none of the patients in group 1 showed grade 0 differentiation, and none of the patients in group 2 showed grade 2 or 3 differentiation. The CIC scores were significantly higher in group 1 (2.12±0.7) than in group 2 (0.57±0.6, P<0.001). CONCLUSION: Ocular surface changes, including squamous metaplasia in the bulbar conjunctiva, can be observed in patients with AS.

Subfoveal choroidal thickness change following pars plana vitrectomy with silicone oil endotamponade for rhegmatogenous retinal detachment.

PURPOSE: To report changes in subfoveal choroidal thickness (SFCT) using spectral-domain optical coherence tomography following pars plana vitrectomy (PPV) with silicone oil (SiO) endotamponade injection and subsequent removal. METHODS: In this prospective study, 24 eyes of 24 patients with macula-off rhegmatogenous retinal detachment (RD) were included. These patients underwent PPV with SiO injection removal. SFCT measurements were taken 2 weeks and 3 months after PPV and SiO injection and 1 month after SiO removal. The contralateral eyes served as controls. RESULTS: Mean SFCT values of the operated eyes were 294.1 ± 70.5 µm and 282.9 ± 80.6 µm 2 weeks and 3 months after PPV and 264.2 ± 63.3 µm 1 month after SiO removal. There was no significant change in SFCT between first and second measurements (p = 0.96). SFCT decrease was statistically significant when first and last measurements were compared (p = 0.03). SFCT percent change was correlated with duration of SiO in the eye and was not correlated with amount of endolaser photocoagulation performed during surgery. SFCT values of the fellow eyes were 317.1 ± 84.8 µm, 313.7 ± 79.8 µm and 306.1 ± 69.1 µm, at 2 weeks and 3 months after PPV and 1 month after SiO removal, respectively. There was no significant difference between the measurements of the control eyes taken at different time intervals (p = 0.430, p = 0.085, respectively). CONCLUSION: SFCT seems to decrease after the removal of the SiO which indicates that choroidal parameters should be taken into account during or after surgery for rhegmatogenous RD.

Conjunctival Impression Cytology and Dry Eye in Patients With Ulcerative Colitis: A Pilot Study.

PURPOSE: The aim of this study was to compare signs of dry eye between ulcerative colitis (UC) patients and healthy subjects. METHODS: Fifteen patients with UC (group 1) and 15 healthy subjects (group 2) were enrolled in this study. Tear volume measurement, Schirmer-I test with no anesthetic, tear break-up time, and conjunctival impression cytology (CIC) were evaluated in both groups. RESULTS: Patients with UC showed lower tear volumes when compared with healthy subjects (P<0.05). There was a statistically significant difference in distribution of CIC grades between groups 1 and 2 (P<0.05). Tear break-up time and Schirmer-I measurements were significantly lower in group 1 compared with group 2 (P<0.05). CONCLUSIONS: The results of this study indicate that UC is associated with demonstrable disturbances in tear function and conjunctival cytology.

The Effect of Dehydration and Fasting on Corneal Biomechanical Properties and Intraocular Pressure.

PURPOSE: To evaluate the changes in corneal biomechanical properties and intraocular pressure (IOP) during fasting period in healthy subjects. METHODS: Seventy-two eyes of 72 fasting subjects (study group), and 62 eyes of 62 nonfasting subjects (control group) were enrolled in this prospective study undertaken at a single university hospital. All subjects underwent complete ophthalmologic examination including ocular biomechanical evaluation with ocular response analyzer. Ocular response analyzer measurement was performed on the right eyes of the subjects between 5.00 and 6.00 PM after approximately 14 hr of fasting for the study group and after a nonfasting period for the control group. The corneal hysteresis, corneal resistance factor, mean corneal compensated IOP (IOPcc), and Goldmann-correlated IOP (IOPg) values were measured with a patented dynamic bidirectional applanation process. RESULTS: Goldmann-correlated IOP and IOPcc measurements in the study group and the control group were found as 13.8±2.8 mm Hg, 14.6±2.6 mm Hg and 16.3±2.2 mm Hg, 15.7±2.4 mm Hg, respectively. There was statistically significant difference within the two groups in IOPg and IOPcc (P<0.001). In addition, corneal hysteresis and corneal resistance factor significantly decreased in study group compared with control group (P<0.001, P=0.012, respectively). CONCLUSION: Prolonged fasting causes a significant decrease in IOPg, IOPcc, corneal hysteresis, and corneal resistance factor in healthy subjects, altering the biomechanical properties of the cornea.

Effect of mydriasis induced by topical 0.5% tropicamide instillation on the corneal biomechanical properties in healthy individuals measured by ocular response analyzer.

PURPOSE: This observational study aims to investigate the effects of tropicamide (0.5%) on corneal biomechanical properties, with the ocular response analyzer (ORA), in healthy individuals. METHODS: Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) measurements of 38 (21 female and 17 male) healthy individuals, before and after 30 min of 0.5% tropicamide instillation, were performed by using the ORA. RESULTS: The mean CH, CRF, IOPg and IOPcc measurements of the eyes were 10.2 ± 1.9 mmHg, 10.3 ± 2.1 mmHg, 15.7 ± 3.4 mmHg, 16.4 ± 3.3 mmHg pre-tropicamide, and 10.4 ± 1.7 mmHg, 10.3 ± 2.1 mmHg, 15.3 ± 3.4 mmHg, 15.8 ± 2.7 mmHg post-tropicamide, respectively. The differences between the pre- and post-tropicamide measurements of the eyes were insignificant (p = 0.184, p = 0.659, p = 0.294, p = 0.150, respectively; paired t-test). CONCLUSIONS: A tropicamide instillation does not lead to significant changes in the corneal biomechanical properties. Therefore, it can be used safely in disease, i.e. in the diagnosis and follow-up ORA as it does not cause any change.

Influence of cyclopentolate hydrochloride on corneal biomechanical properties in healthy individuals.

OBJECTIVE: This observational study aims to investigate the effects of cyclopentolate hydrochloride (1%) on corneal biomechanical properties, with the ocular response analyzer (ORA), in healthy individuals. METHODS: Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) measurements of 36 (15 female and 21 male) healthy individuals, before and after 45 min of 1% cyclopentolate hydrochloride instillation, were performed by the ORA. RESULTS: The mean CH and IOPcc measurements of the eyes were 10.63±1.17 mm Hg and 15.15±2.69 mm Hg, precycloplegia, and 11.09±1.32 mm Hg and 14.16±2.77 mm Hg, postcycloplegia, respectively. The differences between the precycloplegia and postcycloplegia in both measurements were statistically significant (P=0.031, P=0.016, respectively; paired t test). The mean CRF and mean IOPg measurements of the eyes were 10.40±1.16 mm Hg and 14.83±2.56 mm Hg, precycloplegia, and 10.61±1.33 mm Hg and 14.25±2.65 mm Hg, postcycloplegia, respectively. The differences between the precycloplegia and postcycloplegia measurements of the eyes were insignificant (P=0.264 and P=0.100, respectively; paired t test). CONCLUSIONS: A 1% cyclopentolate hydrochloride instillation leads to significant changes in the CH values and IOPcc measurements. This should be taken into account during the evaluation of refractive surgery candidates and in clinical conditions where ORA measurements are considered in the diagnosis and follow-up.

Corneal nerve loss and increased Langerhans cells are associated with disease severity in patients with rheumatoid arthritis.

BACKGROUND/OBJECTIVES: Rheumatoid arthritis (RA) is a multisystem autoimmune disorder characterized by articular and extra-articular manifestations. Neuropathy is a poorly studied manifestation of RA. The aim of this study was to utilize the rapid non-invasive ophthalmic imaging technique of corneal confocal microscopy to identify whether there is evidence of small nerve fibre injury and immune cell activation in patients with RA. SUBJECTS/METHODS: Fifty consecutive patients with RA and 35 healthy control participants were enrolled in this single-centre, cross-sectional study conducted at a university hospital. Disease activity was assessed with the 28-Joint Disease Activity Score and erythrocyte sedimentation rate (DAS28-ESR). Central corneal sensitivity was measured with a Cochet-Bonnet contact corneal esthesiometer. A laser scanning in vivo corneal confocal microscope was used to quantify corneal nerve fibre density (CNFD), nerve branch density (CNBD), nerve fibre length (CNFL), and Langerhans cell (LC) density. RESULTS: Corneal sensitivity (P = 0.01), CNFD (P = 0.02), CNBD (P < 0.001), and CNFL (P < 0.001) were lower, and mature (P = 0.001) and immature LC densities (P = 0.011) were higher in patients with RA compared to control subjects. CNFD (P = 0.016) and CNFL (P = 0.028) were significantly lower in patients with moderate to high (DAS28-ESR > 3.2) compared to mild (DAS28-ESR ≤ 3.2) disease activity. Furthermore, the DAS28-ESR score correlated with CNFD (r = -0.425; P = 0.002), CNBD (ρ = -0.362; P = 0.010), CNFL (r = -0.464; P = 0.001), total LC density (ρ = 0.362; P = 0.010) and immature LC density (ρ = 0.343; P = 0.015). CONCLUSIONS: This study demonstrates reduced corneal sensitivity, corneal nerve fibre loss and increased LCs which were associated with the severity of disease activity in patients with RA.

Assessment of pupillary light reflex using dynamic pupillometry in laser-treated eyes with retinal vein occlusion.

PURPOSE: This study aims to evaluate the pupillary light reflex measured with dynamic pupillometry in patients who underwent retinal laser photocoagulation due to unilateral retinal vein occlusion (RVO). METHODS: A total of 48 patients with unilateral RVO were included in the study. Thirty-four patients had undergone retinal laser photocoagulation while the remaining 14 patients that did not undergo laser treatment were observed for control purposes. Of the laser-treated eyes, 14 eyes (41.2%) had central RVO (CRVO) and 20 eyes (58.8%) had branch RVO (BRVO). Among the 14 patients with RVO without laser treatment, nine eyes (64.3%) had CRVO and five eyes (35.7%) had BRVO. Pupillary light reflexes were assessed with dynamic pupillometry (MonPackOne®; Metrovision, France). The parameters of the eyes with RVO were compared with that of fellow healthy eyes. RESULTS: Mean patient age was 65.8 ± 10.4 years and median time after photocoagulation was 25.5 months. Eyes that received laser photocoagulation had lower pupil contraction amplitude (p = 0.037), prolonged contraction latency (p = 0.027), slower contraction velocity (p = 0.043), and slower dilation velocity (p < 0.001) compared to healthy fellow eyes. Subgroup analysis revealed that eyes with CRVO had lower contraction amplitude (p = 0.013) and slower dilation velocity (p = 0.003), and eyes with BRVO had slower dilation velocity (p = 0.003). Non-laser-treated eyes with RVO revealed no significant difference in any of the pupillary light reflex parameters compared to fellow eyes. CONCLUSION: Laser-treated eyes with RVO demonstrated changes in pupillary light reflex parameters including reduced contraction amplitude, prolonged contraction latency, and slower contraction and dilation velocities measured with dynamic pupillometry.

Assessment of Monocyte/HDL Ratio in Branch Retinal Vein Occlusion.

Purpose: The purpose of this article was to evaluate monocyte count and high-density lipoprotein (HDL) cholesterol levels and their ratio (monocyte/HDL ratio [MHR]) in patients with branch retinal vein occlusion (BRVO).Materials and Methods: A total of 50 participants were included in the study. Participants were divided into two groups: Twenty-five patients diagnosed with BRVO and 25 participants as the control group. Ocular examination findings and hematologic parameters were accessed from the file records and database, retrospectively.Results: The mean MHR was significantly higher in BRVO group compared to the control group (13.4 ± 5.2 vs. 8.1 ± 2.2, p < 0.001). In receiver operating characteristics analysis, the area under the curve for MHR was 0.862, and an MHR of >9.5 predicted BRVO with a sensitivity of 76% and specificity of 70.8%.Conclusion: The present study showed that elevated MHR is significantly associated with BRVO. Therefore, MHR may be a useful marker for the emergence of BRVO.

In Vivo Confocal Microscopic Evaluation of Corneal Nerve Fibers and Dendritic Cells in Patients With Behçet's Disease.

Central and peripheral nervous system involvement may occur during the course of Behçet's disease (BD). In vivo corneal confocal microscopy (CCM) can detect corneal small fiber damage and immune cell density. The aim of this study was to assess central corneal sensitivity, corneal subepithelial nerve plexus morphology and dendritic cell (DC) density in patients with BD. Forty-nine consecutive patients with BD and 30 healthy control subjects were included in this cross-sectional study conducted at a tertiary referral university hospital. Central corneal sensitivity was measured using the contact corneal esthesiometer (Cochet-Bonnet; Luneau, France). The laser scanning CCM (Heidelberg, Germany) was used to quantify corneal nerve fiber density (NFD), nerve branch density (NBD), nerve fiber length (NFL), and DC density. There was a significant reduction in NFD (P = 0.001) and NFL (P = 0.031) and an increase in DC density (P = 0.038) in patients with BD compared to healthy controls, whereas corneal sensitivity (P = 0.066) and NBD (P = 0.067) did not differ significantly. There was no difference in corneal sensitivity, corneal nerve parameters, or DC density between BD patients with [n = 18 (36.7%)] and without a previous history of uveitis (P > 0.05 for all). Disease duration [median (IQR), 6.5 (4.0-14.5) years] correlated with corneal sensitivity (ρ = -0.463; P = 0.001) and NFD (ρ = -0.304; P = 0.034) and corneal sensitivity correlated with NFD (ρ = 0.411; P = 0.003) and NFL (ρ = 0.295; P = 0.039) in patients with BD. CCM demonstrates corneal sub-basal nerve fiber loss and increased DC density, providing a non-invasive ophthalmic means to identify peripheral neuropathy and inflammation in patients with BD.

Assessment of Corneal Sensation, Innervation and Retinal Nerve Fiber Layer in Patients Treated with Multiple Intravitreal Ranibizumab Injections.

PURPOSE: To evaluate the effects of repeated intravitreal ranibizumab injections on corneal sensitivity, corneal sub-basal nerve plexus (SBNP) and peripapillary retinal nerve fiber layer (RNFL) thickness in patients with neovascular age-related macular degeneration (AMD). METHODS: Sixty-six eyes of 33 patients who had received unilateral repeated intravitreal ranibizumab injections (0.5 mg/0.05 ml) for the treatment of AMD and 25 eyes of 25 healthy subjects were included in the study. Central corneal sensation was measured using the contact Cochet-Bonnet esthesiometer. The laser scanning in vivo corneal confocal microscope was used to determine corneal SBNP parameters. The peripapillary RNFL thickness was assessed with spectral-domain optical coherence tomography. Data obtained from the ranibizumab-injected eyes were compared with those of the fellow non-treated eyes and the eyes of the healthy control subjects. RESULTS: The mean number of ranibizumab injections per eye was 8.9±5.0 (range 3-20). There were no statistically significant differences in the central corneal sensitivity threshold and corneal SBNP parameters between the ranibizumab-injected eyes and the fellow untreated eyes or between those with neovascular AMD and the healthy control group (P>0.05 for all). The average peripapillary RNFL thickness of the treated eyes did not differ significantly to the fellow eyes (P = 0.237), and the eyes of healthy control subjects (P = 0.918). There were no significant correlations between the number of ranibizumab injections and any of the study parameters. CONCLUSIONS: Multiple intravitreal injections of ranibizumab seem to have no harmful effects on corneal sensitivity, innervation and peripapillary RNFL thickness in patients with AMD.

Unilateral Recurrent Anterior Uveitis as the Presenting Sign of Bladder Carcinoma.

A 79-year-old male patient was followed for unilateral uveitis with 3 attacks in 10 months, despite initial improvement with steroid therapy. The patient had visual acuity (VA) of counting fingers in right eye, hypopyon and vitritis with no chorioretinal lesions. The left eye was normal. The patient was evaluated for intraocular foreign body, intraocular lymphoma and associated systemic disease and malignancy. Computed tomography of the abdomen showed a mass in the bladder. Biopsy confirmed bladder carcinoma. After resection of the mass, intraocular inflammation improved completely and no attack was noted in the follow-up. In his last examination, two years after the operation, VA was light perception; seclusio pupilla and mature cataracts were seen on biomicroscopy. There was no sign of vitritis on ocular ultrasonography. Evidence is discussed that suggests a link and potential etiology between refractory uveitis with hypopyon and bladder carcinoma. This is the first case of unilateral recurrent uveitis with hypopyon as the initial presenting sign of bladder carcinoma.

Six-month outcomes of corneal crosslinking with dextran-free isotonic riboflavin solution.

PURPOSE: To analyze the short-term clinical and topographic outcomes in patients with keratoconus after corneal collagen cross-linking treatment (CXL) with dextran-free isotonic riboflavin solution. METHODS: In this retrospective case series, 26 eyes from 26 patients with keratoconus were studied. The best corrected visual acuity (BCVA) and refractive and topographic findings were analyzed at a 6-month follow-up. RESULTS: The mean BCVA (Snellen lines) values before and 1, 3, and 6 months after CXL were 0.51 ± 0.2, 0.48 ± 0.2, 0.57 ± 0.2, and 0.64 ± 0.2, respectively, and the difference between the preoperative and 6-month values was statistically significant (p=0.006). The mean spherical equivalent refraction decreased from -5.6 ± 2.4 diopters (D) preoperatively to -5.0 ± 2.1 D, and mean simulated keratometry decreased from 48.5 ± 2.5 D to 47.8 ± 2.6 D at 6 months. (p=0.145 and p=0.001, respectively). In addition, the maximum keratometry decreased progressively and significantly from the preoperative value during follow-up (p=0.003). The central and minimal corneal thicknesses, including those of the epithelium, also decreased from 442.8 ± 25.6 µm and 430.5 ± 23.9 µm preoperatively to 420.7 ± 31.8 µm and 409.3 ± 28.7 µm at the most recent follow-up (p<0.001), respectively. No intraoperative or postoperative complications were observed. CONCLUSIONS: CXL with dextran-free isotonic riboflavin solution appears to be a safe treatment alternative for keratoconus and yields sustained short-term improvements in visual acuity, keratometric readings, and corneal thickness. However, long-term results are needed to confirm these outcomes.

Relationship of inferior oblique overaction to macular and subfoveal choroidal thickness.

PURPOSE: To evaluate the macular and subfoveal choroidal thickness of eyes with inferior oblique muscle overaction (IOOA) using enhanced depth imaging spectral domain optical coherence tomography (EDI SD-OCT). METHODS: The measurements of macular and subfoveal choroidal thickness obtained by EDI SD-OCT of patients with IOOA (24 patients) were compared with those of age- and sex-matched controls (25 subjects). RESULTS: There were no morphological abnormalities of the macula in patients with IOOA or in control subjects. There were no statistically significant differences in macular and subfoveal choroidal thickness between the eyes with IOOA and the eyes of the control subjects (P > 0.05). When the patients with IOOA were assigned to two distinct groups according to the degree of IOOA, the macular thickness did not differ between groups (P = 0.66), whereas subfoveal choroidal thickness measures were significantly lower in eyes with severe IOOA compared to eyes of the controls (P = 0.01). CONCLUSIONS: IOOA has no effect on the morphology and the thickness of the macula. Severe IOOA seems to be related to thinning of subfoveal choroid due to possible external mechanical effect.

Intraocular lens explantation or exchange: indications, postoperative interventions, and outcomes.

PURPOSE: To analyze the indications for explantation or exchange of intraocular lenses (IOLs), which were originally implanted for the correction of aphakia during cataract extraction. METHODS: All cases that involved intraocular lens explantation or exchange in one institution between January 2008 and December 2014 were analyzed retrospectively. RESULTS: In total, 93 eyes of 93 patients were analyzed. The median time interval between implantation and explantation of the anterior chamber intraocular lenses (AC IOL) and posterior chamber intraocular lenses (PC IOL) was 83.40 ± 83.14 months (range: 1-276 months) and 55.14 ± 39.25 months (range: 1-168 months), respectively. Pseudophakic bullous keratopathy (17 eyes, 38.6%) and persistent iritis (12 eyes, 27.8%) in the AC IOL group and dislocation or decentration (30 eyes, 61.2%) and incorrect IOL power (nine eyes, 18.4%) in the PC IOL group were the most common indications for explantation of IOLs. The mean logMAR best corrected visual acuity (BCVA) improved significantly from 1.30 preoperatively to 0.62 postoperatively in the PC IOL group (p<0.001) but did not improve significantly in the AC IOL group (p=0.186). CONCLUSIONS: The primary indication for IOL explantation or exchange was pseudophakic bullous keratopathy in the AC IOL group and was dislocation or decentration in the PC IOL group. PC IOL explantation or exchange is safe and improves visual acuity.

Characteristics of the cornea in patients with pseudoexfoliation syndrome.

PURPOSE: To quantify the morphological alterations in corneal nerve fibers and cells in patients with pseudoexfoliation syndrome (PEX) and their relationship with the presence of hyperreflective endothelial deposits observed using in vivo confocal microscopy. METHODS: One eye each of 37 patients with PEX and 20 age-matched healthy control subjects was evaluated by in vivo corneal confocal microscopy. Patients with PEX were further classified into two groups: those with and without hyperreflective endothelial deposits. We evaluated the densities of basal epithelial cells, anterior and posterior stromal keratocytes, and endothelial cells and structure of sub-basal nerve fibers. RESULTS: The mean anterior and posterior stromal keratocyte and endothelial cell densities and corneal sub-basal nerve plexus variables were significantly lower in patients with PEX compared with those in healthy control subjects. The mean basal epithelial cell density did not significantly differ. CONCLUSION: Eyes with PEX presented decreased corneal sub-basal nerve plexus variables and cell densities in all corneas, except for the mean basal epithelial cell density. Further, a trend of lower corneal sub-basal nerve plexus measurements in patients with hyperreflective endothelial deposits compared with those without endothelial deposits was observed.

Intraoperative corneal thickness monitoring during corneal collagen cross-linking with isotonic riboflavin solution with and without dextran.

PURPOSE: The aim of this study was to analyze and compare corneal thickness changes during corneal collagen cross-linking procedures performed with isoosmolar riboflavin solution with 20% dextran and without dextran in corneal ectatic diseases. METHODS: The patients in this study were analyzed in 2 groups: group 1 receiving riboflavin solution containing 20% dextran and group 2 receiving dextran-free riboflavin solution. Corneal thickness measurements were obtained with ultrasonic pachymetry at 6 different time points: preoperatively and at 0, 15, 30, 45, and 60 minutes after epithelial removal and initiation of ultraviolet A irradiation. RESULTS: Twenty-seven eyes of 27 patients with progressive keratoconus were included in the study. In group 1 (n = 13), the mean preoperative thinnest pachymetric readings were 469.3 ± 8.5 µm, which decreased to 423.8 ± 8.9 µm after deepithelization and further decreased to 385.9 ± 10.9 µm at 15 minutes. The corneal thickness assumed a steady course at the 30-, 45-, and 60-minute measurements (378.9 ± 9.8 µm, 384.5 ± 10.5 µm, and 396.7 ± 9.4 µm, respectively). The initial change was statistically significant (P < 0.01). In group 2 (n = 14), the corneal thickness decreased from 459.4 ± 3.8 µm to 414.7 ± 2.6 µm with deepithelization, after which it increased steadily with the initiation of the dextran-free riboflavin solution. The final measurement in group 2 was 474.1 ± 9.4 µm; the increase at each time point was statistically significant when compared with the previous measurement (P < 0.01). CONCLUSIONS: Using isoosmolar riboflavin solution without dextran causes a steady increase in the corneal thickness during the cross-linking procedure, as opposed to riboflavin with dextran. This result might be beneficial in broadening the spectrum of cross-linking indications in patients with thin corneas.

Six-month outcomes of corneal crosslinking with dextran-free isotonic riboflavin solution / Resultados após seis meses de crosslinking de córnea com solução isotônica de riboflavina sem dextrano

ABSTRACT Purpose: To analyze the short-term clinical and topographic outcomes in patients with keratoconus after corneal collagen cross-linking treatment (CXL) with dextran-free isotonic riboflavin solution. Methods: In this retrospective case series, 26 eyes from 26 patients with keratoconus were studied. The best corrected visual acuity (BCVA) and refractive and topographic findings were analyzed at a 6-month follow-up. Results: The mean BCVA (Snellen lines) values before and 1, 3, and 6 months after CXL were 0.51 ± 0.2, 0.48 ± 0.2, 0.57 ± 0.2, and 0.64 ± 0.2, respectively, and the difference between the preoperative and 6-month values was statistically significant (p=0.006). The mean spherical equivalent refraction decreased from -5.6 ± 2.4 diopters (D) preoperatively to -5.0 ± 2.1 D, and mean simulated keratometry decreased from 48.5 ± 2.5 D to 47.8 ± 2.6 D at 6 months. (p=0.145 and p=0.001, respectively). In addition, the maximum keratometry decreased progressively and significantly from the preoperative value during follow-up (p=0.003). The central and minimal corneal thicknesses, including those of the epithelium, also decreased from 442.8 ± 25.6 µm and 430.5 ± 23.9 µm preoperatively to 420.7 ± 31.8 µm and 409.3 ± 28.7 µm at the most recent follow-up (p<0.001), respectively. No intraoperative or postoperative complications were observed. Conclusions: CXL with dextran-free isotonic riboflavin solution appears to be a safe treatment alternative for keratoconus and yields sustained short-term improvements in visual acuity, keratometric readings, and corneal thickness. However, long-term results are needed to confirm these outcomes.

RESUMO Objetivo: Analisar os resultados clínicos e topográficos curto prazo após crosslinking (CXL) de córnea com solução isotônica de riboflavina sem dextrano, em pacientes com ceratocone. Método: Estudamos 26 olhos de 26 pacientes com ceratocone, nesta série retrospectiva de casos. Melhor acuidade visual corrigida (BCVA), refração e achados topográficos foram analisados aos 6 meses de acompanhamento. Resultados: BCVA pré-operatória (linhas de Snellen) foi de 0,51 ± 0,2. BCVA após CXL foram de 0,48 ± 0,2, 0,57 ± 0,2 e 0,64 ± 0,2 no 1º, 3º e 6º meses, respectivamente. A diferença entre a BCVA pré-operatória e mais recente foi estatisticamente significativa (p=0,006). O equivalente esférico médio diminuiu de -5,6 ± 2,4 dioptrias (D) no pré-operatório para -5.0 ± 2.1 D e a média da ceratometria simulada diminuiu de 48,5 ± 2,5 D para 47, 8± 2,6 D aos 6 meses. (p=0,145 e p=0,001, respectivamente). A ceratometria máxima diminuiu progressivamente durante o acompanhamento com as mudanças sendo significativamente diferentes do valor pré-operatório (p=0,003). As espessuras corneanas central e mínima, diminuiram de 442,8 ± 25,6 µm e 430,5 ± 23,9 µm para 420,7 ± 31,8 µm e 409,3 ± 28,7 µm, respectivamente, na visita mais recente (p<0,001). Não foram observadas complicações intraoperatórias e pós-operatórias. Conclusões: CXL com solução de riboflavina isotônica sem dextrano parece ser uma opção segura de tratamento para o ceratocone com melhora mantida na acuidade visual, ceratometria e espessura corneana, no curto prazo. Resultados a longo prazo são necessários para confirmar estes resultados.