Age prediction using fundus parameters of normal eyes from the Kumejima population study.

PURPOSE: Artificial intelligence can predict the age of an individual using color fundus photographs (CFPs). This study aimed to investigate the accuracy of age prediction in the Kumejima study using fundus parameters and to clarify age-related changes in the fundus. METHODS: We used nonmydriatic CFPs obtained from the Kumejima population study, including 1,646 right eyes of healthy participants with reliable fundus parameter measurements. The tessellation fundus index was calculated as R/(R + G + B) using the mean value of the red-green-blue intensity in eight locations around the optic disc and foveal region. The optic disc ovality ratio, papillomacular angle, and retinal vessel angle were quantified as previously described. Least absolute shrinkage and selection operator regression with leave-one-out cross-validation was used to predict age. The relationship between the actual and predicted ages was investigated using Pearson's correlation coefficient. RESULTS: The mean age of included participants (834 males and 812 females) was 53.4 ± 10.1 years. The mean predicted age based on fundus parameters was 53.4 ± 8.9 years, with a mean absolute error of 3.64 years, and the correlation coefficient between actual and predicted age was 0.88 (p < 0.001). Older patients had greater red and green intensities and weaker blue intensities in the peripapillary area (p < 0.001). CONCLUSIONS: Age could be predicted using the CFP parameters, and there were notable age-related changes in the peripapillary color intensity. The age-related changes in the fundus may aid the understanding of the mechanism of fundus diseases such as age-related macular degeneration.

Choroidal morphologic features in central serous chorioretinopathy using ultra-widefield optical coherence tomography.

PURPOSE: To analyze the choroidal morphological changes in central serous chorioretinopathy (CSC) using ultra-widefield (UWF)-optical coherence tomography (OCT). METHODS: This single-center, case-control study included 65 CSC eyes (52 males; age, 55.6 ± 13.0 years) and 65 healthy eyes (50 males; age, 57.1 ± 17.9 years). UWF-OCT (viewing angle, 200°) with real-shape correction was used to create an automated choroidal thickness (CT) map. The CT map had three sub-areas: the central (0-30°), middle (30-60°), and peripheral areas (60-100°), and was divided by vertical and horizontal lines. Differences in the CT and the CT change rate (CTCR) from the central to peripheral areas were examined between the CSC and control groups after adjusting for subjects' demographic and clinical factors. Furthermore, we assessed the vortex veins dilation patterns (VVDP) in the macula and examined the CT and the CTCR differences between CSC patients and controls for each VVDP. RESULTS: CSC patients had greater CT than those of the controls in all sectors (CSC vs. controls, the peripheral area: supratemporal 284.4 ± 71.2 µm vs. 220.4 ± 71.2 µm, infratemporal 263.3 ± 69.2 µm vs. 195.3 ± 52.3 µm, supranasal 251.9 ± 70.3 µm vs. 189.5 ± 58.1 µm, infranasal 193.6 ± 71.2 µm vs. 146.3 ± 48.9 µm, P < 0.0001 for all sectors). The CTCR was apparently larger in CSC eyes than controls only for the upper-dominant type of VVDP (CSC patients vs. controls, supratemporal 32.1 ± 9.9% vs. 4.6 ± 23.1%, infratemporal 44.0 ± 11.2% vs. 25.6 ± 16.8%, supranasal 42.6 ± 9.8% vs. 22.2 ± 19.4%, infranasal 57.6 ± 41.2% vs. 41.2 ± 13.9%, P < 0.0001 for all sectors). CONCLUSIONS: CSC has a thicker choroid, even in the peripheral areas, and the macular choroidal thickening was more severe in the upper-dominant type of VVDP. VVDP may affect the location of excessive fluid.

Sex determination using color fundus parameters in older adults of Kumejima population study.

PURPOSE: Deep learning artificial intelligence can determine the sex using only fundus photographs. However, the factors used by deep learning to determine the sex are not visible. Therefore, the purpose of the study was to determine whether the sex of an older individual can be determined by regression analysis of their color fundus photographs (CFPs). METHODS: Forty-two parameters were analyzed by regression analysis using 1653 CFPs of normal subjects in the Kumajima study. The parameters included the mean values of red, green, and blue intensities; the tessellation fundus index; the optic disc ovality ratio; the papillomacular angle; and the retinal vessel angles. Finally, the L2 regularized binomial logistic regression was used to predict the sex using all the parameters, and the diagnostic ability was assessed through the leave-one-cross-validation. RESULTS: The mean age of the 838 men and 815 women were 52.8 and 54.0 years, respectively. The ovality ratio and retinal artery angles in women were significantly smaller than that in men. The green intensity at all locations for the women were significantly higher than that of men (P < 0.001). The discrimination accuracy rate assessed by the area-under-the-curve was 80.4%. CONCLUSIONS: Our methods can determine the sex from the CFPs of the adult with an accuracy of 80.4%. The ovality ratio, retinal vessel angles, tessellation, and the green intensities of the fundus are important factors to identify the sex in individuals over 40 years old.

NORMAL PERIPHERAL CHOROIDAL THICKNESS MEASURED BY WIDEFIELD OPTICAL COHERENCE TOMOGRAPHY.

PURPOSE: Choroidal stasis plays an important role in the pathogenesis of many conditions and leads to choroidal thickening. However, the normal peripheral choroidal thickness (PCT) pattern remains unknown. This study investigated PCT and associated factors using ultrawidefield optical coherence tomography in healthy eyes. METHODS: This cross-sectional study included 120 healthy eyes (57 males; age, 52.0 ± 20.5 years). We used choroidal thickness maps created by ultrawidefield optical coherence tomography (viewing angle, 200°) with real-shape correction. The peripheral area was defined from 60° to 100° and further separated vertically and horizontally. The PCT and the correlations between PCT and subjects' characteristics were examined. RESULTS: The PCT were 227.1 ± 57.0 µ m, 199.6 ± 53.9 µ m, 196.6 ± 57.1 µ m, and 148.0 ± 38.2 µ m in supratemporal, infratemporal, supranasal, and infranasal areas, respectively. The thickest peripheral sector was most frequently observed in supratemporal (69.2%). The PCT negatively correlated with age in all regions ( P -values < 0.001) and axial length in supratemporal, supranasal, and infranasal areas ( P -values ≤ 0.003). The temporal PCT was thicker on the side contiguous with the posterior pole Haller's vessels ( P -values ≤ 0.020). CONCLUSION: The PCT is associated with age, axial length, and the running pattern of Haller's vessels.

Simultaneous Occurrence of Buckle Infection and Migration: A Case Report.

Background: When scleral buckling is performed using a #240 encircling band anterior to the equator for rhegmatogenous retinal detachment, buckle migration may occur anteriorly, eroding the rectus muscle. There are few cases of buckle migration occurring simultaneously with buckle infection. Notably, most previous reports included inadequate data on the pathophysiology of buckle migration and did not include the Hess test and perioperative images. Case presentation: A 36-year-old man with a history of atopic dermatitis underwent scleral buckling for rhegmatogenous retinal detachment of the left eye with #287 and #240 encircling bands at Kagoshima University Hospital. Four years later, he developed discharge, redness, and diplopia of the left eye. He was then referred to our hospital because buckle infection was suspected. The buckle was partially visible on the lower nasal side. Optical coherence tomography of the anterior chamber revealed the buckle to be on the nasal side and overlying the medial rectus muscle. Buckle migration and infection in the left eye was diagnosed, and early buckle removal was recommended. Two weeks later, on the day before surgery, conjunctival melting progressed in the nasal and inferior areas, and the buckle was exposed to a greater extent. In the surgical video at the initial surgery, the silicone band was confirmed to pass under the four rectus muscles, specifically the inferior and medial rectus muscles. At the beginning of the second surgery, we confirmed that the buckles were over the inferior and medial rectus muscles. As far as could be observed after buckle removal, the inferior and medial rectus muscles were not present at the normal location. Postoperatively, ocular pain and discharge quickly resolved. The subjective symptoms of diplopia also improved, and the postoperative Hess chart showed an improved ocular movement in the upward and lateral directions. Conclusions: Buckle migration is a rare postoperative complication of scleral buckling; however, patients at risk of buckle migration, such as those with encircling scleral buckle anterior to the eyeball, should be monitored with caution. If a buckle infection develops, buckle migration may occur within a short period, and early buckle removal should be considered.

OCULAR FACTORS RELATED TO PREOPERATIVE ENLARGEMENT OF IDIOPATHIC MACULAR HOLE DIAMETER.

PURPOSE: To determine the preoperative factors that are significantly correlated with an enlargement of an idiopathic macular hole (MH) during the one-month preoperative period. METHODS: This was a retrospective cross-sectional study of patients with MH who had undergone vitrectomy in the Kagoshima University Hospital. The stage of the MH was determined by using spectral domain optical coherence tomography. Patients who had optical coherence tomography images at two time points more than 14 days apart before the vitrectomy were studied. RESULTS: The MH participants were at Stage 2 in 44 eyes, at Stage 3 in 58 eyes, and at Stage 4 in 38 eyes. The rate of increase of the hole diameter was 26.0 ± 42.3% at Stage 2, 5.52 ± 15.5% at Stage 3, and 8.04 ± 18.7% at Stage 4. The rate of change at Stage 2 was significantly greater than that at Stage 3 and Stage 4 (both P < 0.01). In Stage 2, the MH diameter at the initial visit was significantly and negatively correlated with the rate of MH enlargement (r = -0.35, P = 0.021). CONCLUSION: Patients with Stage 2 MHs, especially eyes with small hole diameter, should be considered for early surgery.

Genetic LAMP2 deficiency accelerates the age-associated formation of basal laminar deposits in the retina.

The early stages of age-related macular degeneration (AMD) are characterized by the accumulation of basal laminar deposits (BLamDs). The mechanism for BLamDs accumulating between the retinal pigment epithelium (RPE) and its basal lamina remains elusive. Here we examined the role in AMD of lysosome-associated membrane protein-2 (LAMP2), a glycoprotein that plays a critical role in lysosomal biogenesis and maturation of autophagosomes/phagosomes. LAMP2 was preferentially expressed by RPE cells, and its expression declined with age. Deletion of the Lamp2 gene in mice resulted in age-dependent autofluorescence abnormalities of the fundus, thickening of Bruch's membrane, and the formation of BLamDs, resembling histopathological changes occurring in AMD. Moreover, LAMP2-deficient mice developed molecular signatures similar to those found in human AMD-namely, the accumulation of APOE, APOA1, clusterin, and vitronectin-adjacent to BLamDs. In contrast, collagen 4, laminin, and fibronectin, which are extracellular matrix proteins constituting RPE basal lamina and Bruch's membrane were reduced in Lamp2 knockout (KO) mice. Mechanistically, retarded phagocytic degradation of photoreceptor outer segments compromised lysosomal degradation and increased exocytosis in LAMP2-deficient RPE cells. The accumulation of BLamDs observed in LAMP2-deficient mice was eventually followed by loss of the RPE and photoreceptors. Finally, we observed loss of LAMP2 expression along with ultramicroscopic features of abnormal phagocytosis and exocytosis in eyes from AMD patients but not from control individuals. Taken together, these results indicate an important role for LAMP2 in RPE function in health and disease, suggesting that LAMP2 reduction may contribute to the formation of BLamDs in AMD.

Ten-year changes in visual acuity at baseline and at 2 years after treatment in a Japanese population with age-related macular degeneration.

PURPOSE: We investigated 10-year changes in baseline best-corrected visual acuity (BCVA), as well as functional and anatomical changes at 1 and 2 years after initial treatment, in eyes with treatment-naïve neovascular age-related macular degeneration (nAMD). METHODS: This retrospective, multicenter, case series reviewed patients with treatment-naïve nAMD who underwent initial treatment from 2006 to 2015, using photodynamic therapy (PDT), anti-vascular endothelial growth factor (VEGF), or a combination of PDT and anti-VEGF. BCVA and central retinal subfield thickness (CRST), were measured at baseline and at 1 or 2 years of follow-up. RESULTS: In total, 3096 eyes of 3096 patients were included from 14 hospitals. Mean BCVA at baseline became significantly better over the 10-year study period (P < 0.001). BCVA at 1 year significantly improved from baseline in patients who underwent initial treatment from 2009 to 2015 (P = 0.001, 2009; P = 0.004, 2010; P = 0.01, 2011; P < 0.001, 2012-2015). BCVA at 2 years significantly improved from baseline in patients who underwent initial treatment from 2012 to 2015 (P < 0.001, 2012; P < 0.001, 2013-2015). CRST at 1 year decreased significantly from CRST at baseline, each year from 2006 to 2015 (P < 0.001, 2006-2015). CRST at 2 years decreased significantly from CRST at baseline, each year from 2006 to 2015 (P = 0.03, 2006; P < 0.001, 2007-2015). CONCLUSION: Baseline BCVA with treatment-naïve nAMD tended to become better during the study period. BCVA at 1 year improved in the era of anti-VEGF; BCVA at 2 years improved in patients who underwent initial treatment in 2012 or later; and CRST decreased in each year during the study period.

QUANTIFICATION OF VESSELS OF HALLER'S LAYER BASED ON EN-FACE OPTICAL COHERENCE TOMOGRAPHY IMAGES.

PURPOSE: To quantify the vessels of Haller's layer of normal subjects in en-face optical coherence tomographic images. METHODS: One hundred and seventy-two normal eyes were studied. En-face images of the top 25% slab of Haller's layer was analyzed. The vessel area, vessel length, and mean vessel diameter were calculated. The vessel running pattern was quantified for the degree of symmetry and designated as the "symmetry index." The coefficient of correlation between each choroidal parameter and the age, sex, axial length, and central choroidal thickness was determined. RESULTS: The vessel area was 23.4 ± 3.6 mm2, vessel length was 164.6 ± 24.1 mm, mean vessel diameter was 0.143 ± 0.019 mm, and the symmetry index was 58.6 ± 6.1%. Multiple regression analysis showed that the vessel area was significantly correlated with the age (R = -0.421, P < 0.001) and central choroidal thickness (R = 0.315, P < 0.001). The vessel length was significantly correlated with the age (R = -0.391, P = 0.024) and central choroidal thickness (R = -0.410, P < 0.001). The mean vessel diameter was significantly correlated with the age (R = -0.107, P = 0.024) and central choroidal thickness (R = 0.775, P < 0.001). The correlation between the symmetry index and any clinical findings was not significant. CONCLUSION: Quantification of en-face images of Haller's layer provide new biomarkers of the choroid.

Relationship between peripapillary choroidal thickness and degree of tessellation in young healthy eyes.

PURPOSE: To determine the relationship between the peripapillary choroidal thickness (ppCT) and the degree and distribution of the tessellation in the fundus of normal eyes. METHODS: This was a prospective, observational cross-sectional study of 118 right eyes of young healthy volunteers. The ppCT was measured from the optical coherence tomography (OCT) circle scans manually at eight sectors: the nasal, supranasal superior, supratemporal, temporal, infratemporal, inferior, and infranasal sectors. The subjective degree of the tessellation in the color fundus photographs (CFPs) was classified into three categories: non-tessellated (NT), weakly tessellated (WT), and strongly tessellated (ST) in same sectors. The objective degree of tessellation designated by the tessellation fundus index (TFI) which was calculated as TFI = (R - G)/(R + G + B) using the mean value of the red-green-blue intensities of the CFPs. The differences in the ppCT and TFI for the three tessellation groups were analyzed. The correlations between the TFI and the ppCT were also determined. RESULTS: The mean age of the subjects was 25.8 years and the mean axial length of the eye was 25.5 mm. The inter-rater agreement of the subjective classifications was high with a Fleiss kappa of 0.71. The ppCT was significantly thinner in eyes with higher degrees of tessellation (P < 0.05) in all sectors. The TFIs were significantly and negatively correlated with the ppCTs in all sectors (r = - 0.44 to - 0.24, P < 0.05) except the nasal and the supranasal sectors. CONCLUSION: The degree of peripapillary tessellation is significantly correlated with the ppCT in young healthy eyes, and it has large individual and geographic variations.

Sex judgment using color fundus parameters in elementary school students.

PURPOSES: Recently, artificial intelligence has been used to determine sex using fundus photographs alone. We had earlier reported that sex can be distinguished using known factors obtained from color fundus photography (CFP) in adult eyes. However, it is not clear when the sex difference in fundus parameters begins. Therefore, we conducted this study to investigate sex determination based on fundus parameters using binominal logistic regression in elementary school students. METHODS: This prospective observational cross-sectional study was conducted on 119 right eyes of elementary school students (aged 8 or 9 years, 59 boys and 60 girls). Through CFP, the tessellation fundus index was calculated as R/(R + G + B) using the mean value of red-green-blue intensity in the eight locations around the optic disc. Optic disc ovality ratio, papillomacular angle, retinal artery trajectory, and retinal vessel were quantified based on our earlier reports. Regularized binomial logistic regression was applied to these variables to select the decisive factors. Furthermore, its discriminative performance was evaluated using the leave-one-out cross-validation method. Sex difference in the parameters was assessed using the Mann-Whitney U test. RESULTS: The optimal model yielded by the Ridge binomial logistic regression suggested that the ovality ratio of girls was significantly smaller, whereas their nasal green and blue intensities were significantly higher, than those of boys. Using this approach, the area under the receiver-operating characteristic curve was 63.2%. CONCLUSIONS: Although sex can be distinguished using CFP even in elementary school students, the discrimination accuracy was relatively low. Some sex difference in the ocular fundus may begin after the age of 10 years.

MORE EFFECTIVE SCREENING FOR EPIRETINAL MEMBRANES WITH MULTICOLOR SCANNING LASER OPHTHALMOSCOPE THAN WITH COLOR FUNDUS PHOTOGRAPHS.

PURPOSE: To assess the ability of the multicolor scanning laser ophthalmoscope (MC-SLO) to screen for epiretinal membranes (ERMs). METHODS: A retrospective cross-sectional study of 35 eyes of 32 patients with an ERM detected by optical coherence tomography and 46 eyes of 23 healthy volunteers. The detection of the ERM was graded into three visibility scores-1, not visible, 2, barely visible, and 3, clearly visible-by retina specialists or by ophthalmology residents. The sensitivity and specificity of the detection with the merged image of the MC-SLO or color fundus photographs (CFPs) were calculated. RESULTS: The sensitivity for ERM detection in the MC-SLO and CFP were 91.4% and 65.7% by specialists and 97.1% and 60.0% by residents. The specificity for both devices was 100% by specialists and residents. The visibility score for the MC-SLO images were significantly higher than that for the CFP by both specialists and residents. In addition, the visibility score for the MC-SLO determined by residents was significantly higher than that for the CFP by specialists. CONCLUSION: The detection of an ERM is better with the MC-SLO images than with CFP. Furthermore, the ERM detection in the MC-SLO images by residents was comparable to that by specialists.

Differences of body height, axial length, and refractive error at different ages in Kumejima study.

PURPOSE: To determine the relationships between the axial length (AL), refractive error (RE), and body height (BH) at different ages of a genetically-stable population in Kumejima, Japan. METHODS: Cross-sectional, population-based study. Residents of Kumejima who were ≥ 40-years old were studied. The eligible residents had a thorough ocular examinations including measurements of the AL, RE, and BH. The subjects were divided into decade groups. The relationships between the AL, the RE, and the BH of the different decades were determined. RESULTS: Reliable measurements of the AL of the right eyes were obtained from 2198 (1103 men and 1095 women) normal subjects. There was a significant and negative correlation between the age and the BH (r = -0.44, P < 0.001) and the AL (r = -0.27, P < 0.001). There were significant and positive correlations between the BH and AL in all subjects (r = 0.38, P < 0.001). There was a significant and positive correlation between the BH and the AL in all age brackets (r = 0.26~0.49, P < 0.001). There was a significant and positive correlation between the age and RE (spherical equivalent; r = 0.49, P < 0.001). There were significant and negative correlations between the BH and RE in all subjects (r = -0.29, P < 0.001). CONCLUSIONS: The younger individuals tend to be taller, have longer AL, and are more myopic. Considering the marked improvement of the nutritional status during the growth period of each generation and its close association with BH, nutrition may be one of factors that is related to the increase in the prevalence of myopia in the younger generation.

Running pattern of choroidal vessel in en face OCT images determined by machine learning-based quantitative method.

PURPOSE: To evaluate the new method to quantitate the running pattern of the vessels in Haller's layer in en face optical coherence tomographic (OCT) images using the new algorithm. METHODS: A retrospective and cross-sectional study. The en face image of top 25% slab of Haller's layer was analyzed. The vascular area in these images was calculated after binarization. Then, the vessels were thinned, and the total length of the vessels and the mean vessel diameter were calculated. Based on the angle of vessel running, "natural oblique vessel" was defined. The ratio of the natural oblique vessel to the whole vessels was defined as the "symmetry index". To examine the reproducibility of the software, the images obtained on two different examination dates of the same subject (25 eyes of 25 healthy subjects) were analyzed. Also, to compare the symmetry index and subjective evaluations, 180 eyes and 180 healthy subjects were analyzed. The subjective evaluations classified the images into 3 groups, the Symmetrical, Semi-symmetrical, and Asymmetrical types. Symmetry index was compared in each group. RESULTS: The inter-measurement correlation coefficient (ICC) of the vessel area, vessel length, and vessel diameter were 0.955, 0.934, and 0.954, respectively. The ICC of the symmetry index was 0.926. The symmetry index of the Symmetrical type was 60.4 ± 7.2%, that of the Semi-symmetry type was 56.2 ± 4.6%, and that of the Asymmetry type was 52.6 ± 5.2%. CONCLUSIONS: The present algorithm can analyze vessels in Haller's layer of the en face images of choroid in an objective manner with good repeatability.

Ability of MultiColor scanning laser ophthalmoscope to detect non-glaucomatous retinal nerve fiber layer defects in eyes with retinal diseases.

PURPOSE: To compare the ability of ocular fundus images obtained by Spectralis MultiColor scanning laser ophthalmoscope (MC-SLO) to that obtained by conventional color fundus images (CF) in detecting non-glaucomatous nerve fiber layer defects (NFLDs). METHODS: A cross-sectional, retrospective study. Patients with retinal diseases who had ocular examination with both the MC-SLO and CF instruments at the Kagoshima University from December 2016 to February 2017 were studied. Eyes that had NFLDs with non-glaucomatous optic discs were analyzed. The visibility of the NFLDs was classified into three grades: grade 0, not visible; grade 1, barely visible; and grade 2, clearly visible. The NFLD grade for blue, green, and red scanning lights of the MC-SLO, merged images with three wavelengths and the color and red-free images were determined by two ophthalmologists. These scores were compared by Steel-Dwass tests. RESULTS: Thirty-one eyes of 26 patients with a mean age of 63.1 ± 11.2 years were studied. There were 14 eyes with diabetic retinopathy, 11 eyes with age-related macular degeneration, 3 eyes with a branch retinal vein occlusion, and 3 eyes with an epiretinal membrane/macular hole. Both the intra-rater (0.631-0.790) and inter-rater (0.637-0.733) agreements were good. NFLDs were detected by the blue wavelength in all cases and by green wavelength and merged wavelengths in 90.3% of the images. The mean NFLD grade was 1.58 ± 0.49 for blue light images, 1.13 ± 0.54 for green light images, 0.07 ± 0.24 for red light images, and 1.16 ± 0.56 for merged images. The NFLD score for blue wavelength was significantly higher than that for green and red wavelength images (P < 0.05 and P < 0.01) but not significantly higher than that for the merged images. NFLDs were detected in 12 eyes (38.7%) in the color images and 16 eyes (51.6%) in the red-free images. The NFLD score for the CF and the red-free image was 0.41 ± 0.55 and 0.70 ± 0.67 which is significantly lower than that of blue MC-SLO images. CONCLUSION: The images obtained by MC-SLO are superior to that obtained by CF in detecting NFLDs in eyes with retinal diseases. We recommend MC-SLO imaging to screen for NFLDs in eyes with retinal diseases.

Effect of fluid-air exchange on reducing residual silicone oil after silicone oil removal.

PURPOSE: Our purpose was to determine the effect of fluid-air exchange on the amount of silicone oil (SO) droplets remaining in the vitreous cavity after removal of the main body of the SO. METHODS: This was a retrospective comparative study of 56 eyes of 56 patients that had undergone vitrectomy with SO tamponade. Fluid-air exchange was performed during surgery in 30 eyes [Air Ex(+) group] and was not done in 26 eyes [Air Ex(-) group]. All of the eyes were examined by ultrasonography, and the images were converted to binarized image. The amount of residual SO droplets/vitreal area in the images was expressed as the, "silicone oil index (SOI)". The correlations between SOI and clinical findings were determined. RESULTS: The SOI was significantly correlated with the axial length (AL, R = 0.444, P = 0.023). The SOI in the Air Ex(+) group was significantly higher (7.4 ± 2.6%) than in the Air Ex(-) group (4.9 ± 3.4%; P = 0.004). Multiple linear regression analyses showed that the SOI was independently and significantly correlated with the AL and the Air Ex(+) group (P = 0.003, P = 0.006, respectively). CONCLUSIONS: Fluid-air exchange during vitrectomy to remove residual SO is not effective. Our findings indicate that it may increase the amount of residual SO droplets.

CHOROIDAL STRUCTURE ALTERED BY DEGENERATION OF RETINA IN EYES WITH RETINITIS PIGMENTOSA.

PURPOSE: To compare the structural characteristics of the choroid in the areas with greater retinal degeneration to the areas with less retinal degeneration in eyes with retinitis pigmentosa (RP). METHODS: Patients with RP who had a hyperautofluorescent ring were studied. The choroidal images obtained by enhanced depth imaging optical coherence tomography located 7,500 µm from the optic disk in the horizontal plane were analyzed. The cross-sectional areas of the total, luminal, and stromal choroid were measured. The area within the hyperautofluorescent ring was defined as the "central choroid" with less retinal degeneration. RESULTS: Thirty-seven eyes of 24 patients with RP were studied. The cross-sectional area of the total choroid was significantly smaller in the RP eyes than that in the control eyes (P < 0.01). The stromal areas of the choroid were not significantly different from the stromal areas of the controls. However, the luminal areas of the nasal and temporal choroid in the RP eyes were significantly smaller than that of the corresponding areas of the controls. The ratio of the luminal area to the total choroidal area in the central choroid was 68.0 ± 3.3% which was significantly larger than that of the nasal or the temporal choroid (P < 0.01). CONCLUSION: The choroidal structure is differentially altered in eyes with RP. The changes in the choroid were dependent on whether they were located within the hyperautofluorescent or outside the hyperautofluorescent ring.

PERMEABILITY AND ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR EFFECTS OF BEVACIZUMAB, RANIBIZUMAB, AND AFLIBERCEPT IN POLARIZED RETINAL PIGMENT EPITHELIAL LAYER IN VITRO.

PURPOSE: To determine the effects of bevacizumab, ranibizumab, and aflibercept on the permeability and the effects of anti-vascular endothelial growth factor (VEGF) on highly polarized retinal pigment epithelial cells (RPECs) in vitro. METHODS: Highly polarized RPECs were cultured in the upper chamber of a Transwell system. Anti-VEGF antibodies were added to the upper chamber, and the concentrations of the drugs in the lower chambers were measured. The permeability rates of the three anti-VEGF drugs through the RPEC layer and the concentration of VEGF in each chamber were determined. RESULTS: The permeability of aflibercept was significantly lower by about 40% than that of bevacizumab through the RPEC layer (P < 0.05). Ranibizumab was significantly more permeable through the RPECs than bevacizumab (180% of bevacizumab, P < 0.05). Although VEGF was almost absent in the upper chamber after exposure to the 3 antibodies, it was decreased more significantly with aflibercept than with bevacizumab in the lower chamber (2.8% vs. 65.8% of control; P < 0.01). Ranibizumab also decreased the VEGF level compared with bevacizumab (31.7% vs. 65.8% of control; P < 0.01). CONCLUSION: The greater reduction of the amount of VEGF in the lower chamber by aflibercept and ranibizumab than bevacizumab may explain why aflibercept and ranibizumab are more effective than bevacizumab against type 1 choroidal neovascularization.

Association of lifestyle and body structure to ocular axial length in Japanese elementary school children.

BACKGROUND: The purpose of this study is to determine whether the lifestyle and body stature are significantly associated with the axial length (AL) of the eyes of Japanese third grade students. METHODS: A prospective, cross sectional, observational study was performed on 122 third grade students consisting of 61 boys and 61 girls ages 8 to 9 years. The AL, body height, body weight, and body mass index (BMI) were measured. The lifestyle was determined by activities such as the daily duration of indoor studying, television viewing, use of computers and smart phones, outdoor activity time, bed time, Japanese or Western dietary habits, and parental myopia were investigated by a questionnaire with three or five grade levels. The relationship between AL and the questionnaire variables were analyzed by Spearman's correlation analyses. RESULTS: Westernized dietary habits (r = -0.24, P = 0.01), duration of computer and smart phone use (r = 0.24, P = 0.008), parental myopia (r = 0.39, P < 0.001), body weight (r = 0.26, P = 0.005), and BMI (r = 0.23, P = 0.011) were significantly correlated with the AL. Multiple logistic regression analyses showed that the sex [r = -0.48; 95% confidence interval (CI) -0.80 to -0.17, P = 0.003], body weight (r = 0.04; 95% CI 0.02 to 0.07, P = 0.038), westernized dietary habits (r = -0.30; 95% CI -0.55 to -0.05, P = 0.021), and parental myopia (r = 0.40; 95% CI 0.20 to 0.61, P < 0.001) were significantly and independently correlated with the AL. CONCLUSIONS: The body weight and parental myopia and westernized dietary habits are factors significantly associated with myopia. Changing from Japanese food style to westernized food style might increase the risk of progression of school myopia.

AMOUNT OF RESIDUAL SILICONE OIL IN VITREOUS CAVITY IS SIGNIFICANTLY CORRELATED WITH AXIAL LENGTH.

PURPOSE: To determine the parameters of the eye that are significantly correlated with the amount of residual silicone oil remaining after most of it is removed by vitrectomy. METHODS: Nineteen eyes of 19 patients who had silicone oil removed were studied. The day after the surgery for silicone oil removal, B-scan ultrasonography was performed, and the residual silicone oil droplets were observed as hyperechoic particles in the ultrasonographic images. The images of the vitreous cavity were binarized, and the ratio of area of hyperechoic particles to the total vitreous area was quantified and named the silicone oil index (SOI). The correlations between SOI and clinical findings were determined. RESULTS: The SOI was significantly and positively correlated with the axial length (AL) and the preoperative intraocular pressure (AL, R = 0.676, P = 0.002; preoperative intraocular pressure, R = 0.771, P < 0.001). Partial correlation analysis showed that the AL remained significantly correlated with the SOI but the preoperative intraocular pressure was not (AL, R = 0.734, P = 0.001; preoperative intraocular pressure, R = 0.417, P = 0.096). None of the other clinical factors was significantly correlated with the SOI. CONCLUSION: Considering the significant correlation between the amount of residual silicone oil and the AL of the eye, myopic eyes should be carefully scrutinized for residual silicone oil.