Factors affecting the response to subthreshold micropulse laser therapy used in center-involved diabetic macular edema.

The purpose of this study was to investigate the effect of the status of retinal pigment epithelium (RPE) and HbA1c levels on the efficacy of the subthreshold micropulse laser (SMPL) in the treatment of center-involving diabetic macular edema (DME). A total of 20 eyes of 20 patients (mean age 57.9 ± 9.7 years) who were diagnosed with center-involving DME and treated with SMPL for refusing intravitreal injection and 20 eyes of 20 age- and sex-matched healthy participants were enrolled. All patients were followed up in the 1st and 3rd months after SMPL. For measurement of RPE area central 1000 microns, macular EDI-OCT scans were binarized by using the public domain software ImageJ, with a semi-automated technique. There was a significant increase in BCVA values and a significant decrease in CMT values during follow-up. The area of RPE before SMPL was significantly thinner in the patient group (p: 0.004). When the areas of RPE before and 3 months after SMPL were compared, no significant change was observed (p: 0.437). When the relationship between pre-treatment area of RPE and HbA1c was examined, an inverse correlation was observed (p: 0.018). The patients were evaluated by dividing them into 2 groups as 2nd session SMPL required and not required, and the area of RPE was smaller in the group requiring 2nd session SMPL (p: 0.030). The status of central RPE may be a determining factor on the response to treatment. Additionally, HbA1c levels may have an impact on treatment efficacy.

Presumed Retinal Metastasis from Lung Adenocarcinoma: A Case Report and Literature Review.

A 63-year-old Caucasian man with metastatic lung adenocarcinoma undergoing chemotherapy and external radiotherapy was referred for routine eye examination. Although he was asymptomatic, ocular examination revealed a relatively well-circumscribed whitish retinal lesion measuring 0.5 × 0.5 × 0.5 mm located along the inferotemporal vascular arcade in the right eye. Optical coherence tomography (OCT) showed a hyperreflective dome-shaped lesion occupying the inner retinal layers with few hyperreflective dots overlying the retina in the posterior vitreous consistent with tumor cells. Fluorescein angiography revealed early hyperfluorescence and late staining without leakage at the lesion site. A diagnosis of presumed retinal metastasis from lung adenocarcinoma was made. At 2 months follow-up after completion of chemotherapy, the retinal lesion was found to have regressed completely leaving minor irregularities in the inner retinal layers on OCT. To date, there have been only 41 cases of carcinoma metastasis to the retina reported in the literature including the current case. Despite its rarity, retinal metastasis should be considered in the differential diagnosis of a white-yellow retinal mass with/without overlying vitreous cells especially in patients with a history of systemic cancer.

Risk factors for progression following corneal collagen crosslinking in keratoconus.

PURPOSE: To assess risk factors for progression following corneal collagen crosslinking (CXL) in eyes with keratoconus. METHODS: Charts of patients who developed progression following conventional CXL treatment (Dresden protocol) were retrospectively evaluated in two centers (Center 1 and Center 2). 871 eyes of a total of 676 patients were analyzed. Progression was defined as > 1 diopter (D) increase in maximum keratometry (Kmax) readings compared to baseline. RESULTS: Progression was noted in 20 eyes of 20 patients (progression rate 3%). The mean age of the patients was 17.65 ± 5.76 (11-34)-years-old, and the mean follow-up following CXL was 36.70 ± 25.72 (12-84)-months-old. The gender distribution was 13 (65%) females and seven (35%) males. Four eyes (20%) had mild, 13 eyes (65%) had moderate, and three eyes (15%) had severe keratoconus at baseline. Fifteen eyes (75%) had allergic conjunctivitis, and 20 eyes (100%) reported eye-rubbing. Cone location was central in 17 (85%) eyes, and peripheral in 3 (15%) eyes. A mean of 2.21 ± 1.30 D (1.00-5.30 D) steepening was determined at Kmax 6 to 82 months following CXL treatment. CONCLUSIONS: Progression rate was found to be higher in the patients under the age of 17 years, female gender, allergic conjunctivitis, high preoperative Kmax (> 57 D), thin corneas (< 430 µm). The majority of progressive patients were central cone and moderate keratoconus.

Efficacy of the subthreshold micropulse yellow wavelength laser photostimulation in the treatment of chronic central serous chorioretinopathy.

AIM: To evaluate the efficacy and safety of subthreshold micropulse yellow laser (SMYL) in the treatment of chronic central serous chorioretinopathy (CCSC). METHODS: The medical records of 58 eyes of 58 patients with CCSC were reviewed. A 577-nm SMYL system was used for the treatment. Fundus fluorescein angiography was used as the primary method of identifying CCSC, and resolution of subretinal fluid (SRF) evaluated by optical coherence tomography (OCT) and fundus autofluorescence. Central macular thickness (CMT), central macular volume (CMV), total macular volume (TMV), subfoveal choroidal thickness (SFCT), subretinal fluid height (SRFH), and subfoveal fluid basement diameter values were measured by spectral domain-OCT (SD-OCT) for all eyes. RESULTS: The mean age of the patients was 42.4±9.9 (range: 20-72)y. The mean follow-up was 11.4±8.5 (range: 6-37)mo. Median BCVA at at the final follow up after treatment was statistically significant from the baseline. Complete SRF resolution was 12.1% of the eyes in the 1st month, 67.2% of the eyes in the 3rd month and 67.2% of the eyes in the last follow up. The initial median CMT, CMV, TMV, and SFCT values before treatment was significantly higher than 3rd month visit values (P<0.001). In the multivariate analysis performed, age and disease duration were found to be a risk factor for persistent SRF (P=0.017, P=0.016, respectively). CONCLUSION: SMYL treatment provides a significant anatomical and functional improvement and is effective in eliminating SRF in eyes with CCSC.

Carnitine analysis in pterygium / Análise de carnitina no pterígio

ABSTRACT Purpose: The aim of the present study was to measure the free carnitine and acylcarnitine levels in pterygium tissue and normal conjunctival tissue at the metabolomics level using tandem mass spectrometry. Methods: In this prospective, clinical randomized study, pterygium tissues and normal conjunctival tissues taken during pterygium excision with autograft were compared regarding their free carnitine and acylcarnitine profiles. After tissue homogenization, carnitine levels were measured using tandem mass spectrometry. The data were statistically analyzed with the Wilcoxon signed-rank test. Results: Pterygium and normal conjunctival tissue samples from a single eye of 29 patients (16 females, 13 males; mean age, 54.75 ± 11.25 years [range, 21-78 years]) were evaluated. While the free carnitine (C0) level was significantly high in the pterygium tissue (p<0.001), acylcarnitine levels were significantly high in some esterized derivatives (C2, C5, C5:1, C5DC, C16:1, C18, methylglutarylcarnitine) (p<0.05). No statistically significant difference was determined for the other esterized derivatives (p>0.05). Conclusion: That the carnitine levels in pterygium tissue were higher suggests that acceleration of cell metabolism developed secondary to chronic inflammation and the premalignant characteristics of pterygium tissue. High carnitine levels may also effectively suppress the apoptosis process. The data reported in our study indicate that further, more extensive studies of the carnitine profile could help clarify the pathogenesis of pterygium.

RESUMO Objetivo: O objetivo deste estudo foi medir os níveis de carnitina livre e acil-carnitina a nível metabolómico com espectrometria de massa em tandem no tecido do pterígio e no tecido conjuntivo normal. Método: Neste estudo prospetivo, clínico e aleatório, os tecidos de pterígio e os tecidos normais de conjuntiva, retirados durante a cirurgia de pterígio com autoenxerto, foram comparados em relação ao perfil de carnitina livre e de acil-carnitina. Após a homogeneização dos tecidos, os níveis de carnitina foram medidos por espectrometria de massa em tandem. A análise estatística dos dados foi realizada com o teste dos postos sinalizados de Wilcoxon. Resultados: A avaliação foi feita através de amostras de tecido pterígio e de conjuntiva normal de um único olho de 29 pacientes (16 mulheres, 13 homens). A média de idade dos pacientes foi de 54,75 ± 11,25 anos (faixa dos 21 aos 78 anos). Enquanto o nível de carnitina livre (C0) foi significativamente elevado no tecido pterígio (p<0,001), os níveis de acil-carnitina foram significativamente elevados em alguns derivados esterificados (C2, C5, C5: 1, C5DC, C16:1, C18, metilglutaril carnitina) (p<0,05). Não foi determinada uma diferença estatisticamen te significante noutros derivados esterificados (p>0,05). Conclusão: Os níveis mais elevados de carnitina no tecido do pterígio sugerem que a aceleração do metabolismo celular se tenha tornado secundária com o efeito da inflamação crónica e o caráter pré-maligno do tecido do pterígio. Os níveis elevados de carnitina também podem ser eficazes na supressão do processo de apoptose. Os dados obtidos no estudo indicam que estudos mais extensivos do perfil da carnitina contribuiriam para o esclarecimento da patogénese do pterígio.

Sterile Corneal Infiltrate Management After Corneal Crosslinking in Pediatric Keratoconus.

A 6-year-old female was admitted to the ophthalmology department with a preliminary diagnosis of keratoconus. An accelerated cross-linking (CXL) protocol (9 mW/cm2 in 10 minutes) was performed on the right eye. On postoperative day 2, a slit-lamp examination revealed 2 corneal infiltrates with grade 3 haze. Since there was no growth in the cultivated cultures and no response to topical antibiotic treatment, the infiltrates were considered to be sterile, and topical 1% prednisolone drops were applied hourly. Despite topical steroid treatment of 1% prednisolone on postoperative day 5, no significant improvement was observed in the patient's symptoms and slit-lamp findings. Therefore, systemic 1 mg/kg prednisolone (total dose, 15 mg) was added to the treatment on postoperative day 5. One day after initiating the systemic steroid treatment, the infiltrates had shrunk, and the patient's complaints decreased. In patients with keratoconus who are under 10 years of age, the addition of a potent steroid regimen to the treatment may be essential in cases with suspected infiltrates after CXL treatment.

Carnitine analysis in pterygium.

PURPOSE: The aim of the present study was to measure the free carnitine and acylcarnitine levels in pterygium tissue and normal conjunctival tissue at the metabolomics level using tandem mass spectrometry. METHODS: In this prospective, clinical randomized study, pterygium tissues and normal conjunctival tissues taken during pterygium excision with autograft were compared regarding their free carnitine and acylcarnitine profiles. After tissue homogenization, carnitine levels were measured using tandem mass spectrometry. The data were statistically analyzed with the Wilcoxon signed-rank test. RESULTS: Pterygium and normal conjunctival tissue samples from a single eye of 29 patients (16 females, 13 males; mean age, 54.75 ± 11.25 years [range, 21-78 years]) were evaluated. While the free carnitine (C0) level was significantly high in the pterygium tissue (p<0.001), acylcarnitine levels were significantly high in some esterized derivatives (C2, C5, C5:1, C5DC, C16:1, C18, methylglutarylcarnitine) (p<0.05). No statistically significant difference was determined for the other esterized derivatives (p>0.05). CONCLUSION: That the carnitine levels in pterygium tissue were higher suggests that acceleration of cell metabolism developed secondary to chronic inflammation and the premalignant characteristics of pterygium tissue. High carnitine levels may also effectively suppress the apoptosis process. The data reported in our study indicate that further, more extensive studies of the carnitine profile could help clarify the pathogenesis of pterygium.

Tear Organic Acid Analysis After Corneal Collagen Crosslinking in Keratoconus.

OBJECTIVES: This study examined changes in the levels of organic acids, which are important tear metabolites, after corneal collagen crosslinking (CXL) treatment for keratoconus. METHODS: This prospective, nonrandomized, interventional case series included a single eye from 24 patients who were scheduled to receive CXL treatment (Dresden protocol) for progressive keratoconus. Before CXL treatment and at 6 months after treatment, tears were collected in capillary tubes. The patients were separated into four groups as males, females, and ages 18 years younger and >18 older. The organic acid profiles of the tear samples were analyzed using mass spectrometry. RESULTS: An evaluation was made of 12 females and 12 males with a mean age of 19.20±4.06 years (range: 12[FIGURE DASH]27 years). The greatest percentage increase in organic acids after CXL treatment was observed for N-acetyl-L-aspartic acid (66% increase). The organic acid showing the greatest decrease was 3-OH butyric acid (61% decrease). A decrease of 46% was found (P=0.263) in the lactic acid/malic acid ratio. CONCLUSION: Metabolomic studies of tears could facilitate a new and objective process in the follow-up period or in the determination of prognosis after CXL treatment for diseases such as keratoconus, which has a multifactorial etiology.

Metabolomics analysis in pterygium tissue.

PURPOSE: The aim of the study was to measure amino acid levels with the metabolomics analysis in pterygium tissue and normal conjunctiva tissue. MATERIALS AND METHODS: In this prospective, randomized, clinical study, a comparison of the amino acid profile of pterygium tissue and normal conjunctiva tissue taken during autograft pterygium surgery was made. After homogenization of the tissues, amino acid levels were measured with chromatography-mass spectrometry (LC-MS/MS) in the biochemistry laboratory. Statistical analysis was made using the Wilcoxon signed-rank test. RESULTS: Evaluation of pterygium and normal conjunctiva tissues of 29 patients, comprising 16 females and 13 males with a mean age of 54.75 ± 11.25 years (range 21-78 years) was made. While a dramatic increase was observed in all the amino acid levels in the pterygium tissue compared to the normal conjunctiva (p > 0.05), only the increases in arginine, methionine, glycine and tyrosine amino acids were determined to be statistically significant (p < 0.01), (p = 0.028), (p = 0.038), (p = 0.046). CONCLUSION: Pterygium is known to be degenerative inflammatory fibrovascular tissue. When the aetiology is examined in depth, several metabolic processes are seen to have an effect. Further studies of the amino acid profile with more extensive patient series could confirm the data obtained in the current study and contribute to the clarification of the pathogenesis of pterygium.

An Analysis of Scheimpflug Holladay-Equivalent Keratometry Readings Following Corneal Collagen Cross-Linking.

OBJECTIVES: The aim of this research was to compare Holladay equivalent keratometry readings (EKR) and anterior corneal simulated keratometry (SimK) values in keratoconus cases following corneal collagen cross-linking (CXL) treatment. METHODS: This study included 42 eyes of 30 patients with progressive keratoconus. Scheimpflug imaging was performed pre-CXL and at post-CXL months 6 and 12. The mean Holladay EKR and SimK measurements from 1mm to 7mm were compared and repeated variance analysis was performed. RESULTS: The mean age of the patients was 18.93±3.82 years (range: 12-27 years). A reduction was observed in the EKR and SimK values at 6 and 12 months postoperatively compared with the preoperative values, but the difference was not statistically significant (p>0.05). In the mild keratoconus group, the keratometric measurements were lower after treatment. Similar measurements were obtained in the moderate and severe keratoconus groups before and after treatment. In 1 patient, there was an increase of >1 diopter in the maximum keratometry value. No complications developed that would lead to vision loss. CONCLUSION: Corneal collagen CXL treatment is known to be effective to a depth of two-thirds of the anterior corneal stroma. The results of this study showed that Holladay EKR measurements differed from SimK measurements, especially in cases of mild keratoconus. In addition to anterior corneal surface measurements, methods that can evaluate anterior and posterior surface curves could provide more accurate results in progression analysis.

Progression Analysis with ABCD Grading System following Corneal Collagen Cross-Linking in Keratoconus.

OBJECTIVES: To evaluate the ABCD grading system used in follow-up of keratoconus progression after the corneal collagen cross-linking (CXL) treatment in different Kmax groups. METHODS: This study included 57 eyes of 43 patients applied with CXL treatment for progressive keratoconus. All the patients were applied with the standard CXL protocol (Dresden). According to the changes in the Kmax value at the end of 12 months postoperatively (0-1D, 1-2D, >2D), the groups were separated as steepening and flattening. Scheimpflug progression parameters, such as ABCD keratoconus grading systems, were evaluated in six different groups. The Paired Samples t-test was used in the evaluation of parameters with normal distribution and the Wilcoxon test for parameters not showing normal distribution. A value of p<0.05 was accepted as statistically significant. RESULTS: Mean age of patients was 18.37±3.86 years (11-28 years). According to the ABCD grading system, 0.19 significant regression was determined in grade A (p=0.014) and 0.24 in grade D (p<0.0001). 0.10 progression was seen in grade B (p=0.089), and 0.11 in grade C (p=0.011). In the mean Kmax value 0.25±0.42, D flattening was seen (p=0.137). CONCLUSION: The anterior corneal surface grade in ABCD system is correlated with Kmax in different groups. However, the posterior corneal surface parameter is not correlated with Kmax in 1-2 D steepening and >2D flattening groups. Although there is an increase in posterior elevation after CXL, despite excessive Kmax flattening, it would be inaccurate to consider this increase as an indicator of topographic progress.

Comparison of Holladay equivalent keratometry readings and anterior corneal surface keratometry measurements in keratoconus.

PURPOSE: To compare the accuracy of the anterior corneal simulated keratometry (SimK) and the Holladay equivalent keratometry reading (EKR) provided by a Scheimpflug camera (Pentacam HR) with the keratometry (K) provided by a Placido system (T-Cone topography) in keratoconus and control eyes. METHODS: This prospective study included 40 consecutive patients with keratoconus and 40 voluntary participants with no ocular complaints. Any patients with corneal scar, corneal trauma, history of corneal surgery or contact lens usage were excluded from the study. Mean SimK and Holladay EKR measurements were taken with Pentacam HR in the 2, 3, and 4.5 mm corneal zones, and these values were compared with the T-Cone mean K value with the Placido topography system attachment on the Lenstar LS 900. Statistical analysis was performed using the paired Student's t test and the Bland-Altman analysis. RESULTS: A statistically significant difference was determined between the Placido K and the Scheimpflug EKR 2, 3, 4.5 mm and SimK values in the keratoconus group (p < 0.05). In the analyses which showed a difference between the SimK and Holladay EKR, it was observed that as the diameter of the corneal zone increased, the 95% LoA values were extended. No statistically significant difference was determined between the SimK and EKR 2 mm values (p > 0.05). In the control group, there was no statistically significant difference between any of the keratometric values. CONCLUSION: In diseases which affect the posterior corneal surface, such as keratoconus, it is thought that because of the asymmetrical peripheral placement of the corneal apex, as the corneal diameter increases there could be an error increase of 1-3 mm in keratometric systems evaluating the anterior surface.

Pediatric Corneal Collagen Cross-Linking: Long-Term Follow-Up of Visual, Refractive, and Topographic Outcomes.

PURPOSE: To evaluate the long-term visual, refractive, and topographic outcomes of corneal collagen cross-linking (CXL) in the management of pediatric keratoconus. METHODS: Forty eyes of 40 consecutive patients with progressive keratoconus aged below 19 years were enrolled in this prospective study. All patient eyes underwent CXL with the standard (Dresden) protocol. Uncorrected distance visual acuity, best spectacle-corrected distance visual acuity, manifest refraction, slit-lamp biomicroscopy, corneal topography, corneal aberrometry, and endothelial cell counts were evaluated at baseline and at all postoperative follow-up examinations until month 48. RESULTS: Mean age of patients was 15.2 ± 1.9 years (10-18 years). Follow-up was 4 years. The mean improvements in uncorrected distance visual acuity (from 0.9 ± 0.3 logMAR to 0.5 ± 0.3 logMAR) and best spectacle-corrected distance visual acuity (from 0.4 ± 0.2 logMAR to 0.1 ± 0.1 logMAR) were statistically significant at month 48 (P = 0.0001). The mean Kmax decreased from 58.4 ± 5.5 D at baseline to 57.0 ± 5.3 D at month 48 (P = 0.04). Significant improvements in topographic and elevation indices and corneal aberrations were also noted after postoperative month 6. There was no change in the mean endothelial cell density (P > 0.05), and there was no progression or sight-threatening complication in any patient eye. CONCLUSIONS: Corneal CXL seems to be safe and effective in halting the progression of keratoconus in pediatric patients at 4-year follow-up. In addition, the procedure provides improvements in visual, refractive, topographic, and corneal aberrometric measurements.

Outcome of Two Corneal Collagen Crosslinking Methods in Bullous Keratopathy due to Fuchs' Endothelial Dystrophy.

Four eyes of 2 patients with corneal edema due to Fuchs' endothelial dystrophy were treated with CXL using the standard protocol. Since no improvement in visual acuity, corneal clarity, thickness, or pain sensation was evident in any eye at month 12, 2 eyes of the 2 patients were retreated, this time, following intraoperative corneal dehydration with glycerol 70% drops. This retreatment also failed to produce any significant effect on vision, corneal clarity, thickness, or pain in either eye. Collagen crosslinking with the current protocols may not be effective in the management of eyes with corneal edema due to Fuchs' endothelial dystrophy. Further studies are required to establish the efficacy of CXL and optimize the technique and/or dehydration method utilized in these cases.