Intravitreal injection of erythropoietin protects against retinal vascular regression at the early stage of diabetic retinopathy in streptozotocin-induced diabetic rats.

A single intravitreal injection of erythropoietin (EPO) (50 ng/eye) or phosphate-buffered saline was administered to 5-week-old Sprague-Dawley rats at the onset of diabetes mellitus (DM) to determine and evaluate the protective effect of EPO on retinal microvessels. DM was induced by an intraperitoneal injection of streptozotocin (STZ; 60 mg/kg body weight). Morphological changes in microvessels in flat retinal preparations were evaluated during the subsequent 4 weeks by three-dimensional imaging of all blood vessels stained with fluorescein isothiocyanate-conjugated tomato lectin, following immunofluorescence techniques. No marked differences were observed in the shape or density of retinal vessels and the number of retinal capillary branches of the four groups [control, EPO, DM, and DM/EPO] up to 4 weeks after STZ administration. We also observed unique type IV collagen-positive filamentous structures that lacked both cellular elements and blood circulation (lectin-/type IV+ acellular strands), suggesting regressed vessel remnants. The lectin-/type IV+ acellular strands were detected soon after the onset of DM in the diabetic rats, and the number of these structures increased in the DM group (P < 0.01). A single intravitreal injection of EPO caused a significant reduction in the number of lectin-/type IV+ acellular strands to levels observed in the control group. However, the lectin-/type IV+ acellular strands were observed in the central area of the retina near the optic disc in all four groups. Intravitreal injection of EPO resulted in downregulation of the EPO receptor, vascular endothelial growth factor (VEGF), and VEGF receptor at 4 weeks. We conclude that EPO may play a primary role against the progression of diabetic retinopathy by reducing blood vessel degeneration at a very early disease stage.

[Association between age and chorioretinal hemodynamics in normal volunteers examined with laser speckle flowgraphy].

PURPOSE: To investigate the relationship between age and chorioretinal hemodynamics in normal volunteers examined with Laser speckle flowgraphy (LSFG-NAVI). SUBJECTS AND METHODS: 107 eyes of 107 healthy volunteers aged from 21 to 78 years old were included. Laser speckle flowgraphy measurements of relative blood velocity (mean blur rate: MBR), skewness in the wave of blood velocity (Skew) and blowout score (BOS), which indicates ease of blood flow, were obtained as parameters of chorioretinal hemodynamics. MBR and BOS were measured on the optic disc and macula, and BOS and Skew were measured in retinal arteries and veins. RESULTS: There was a negative correlation between age and MBR on the optic disc and macula. There was a negative correlation between age and BOS on the optic disc, macula, retinal arteries and retinal veins. CONCLUSION: There was a negative correlation between MBR, BOS and age in all measurement areas. MBR and BOS may serve as indexes for a new interpretation of fundus pathology including age-related arterial sclerosis.

Macular microcirculation in patients with epiretinal membrane before and after surgery.

BACKGROUND: To investigate blood flow velocity (BFV) in the perifoveal capillaries before and after vitreous surgery for patients with epiretinal membrane (ERM). METHODS: Twenty-one eyes in patients with ERM and 16 eyes in healthy subjects were involved in this study. Fluorescein angiography was performed using a scanning laser ophthalmoscope and BFV was analyzed by the tracing method. Foveal thickness (FT) was measured by optical coherence tomography. RESULTS: BFV was significantly slower in the ERM patients (1.04 ± 0.10 mm/s) than in the healthy subjects (1.49 ± 0.11 mm/s ) (p = 0.0010). BFV in the ERM patients 6 months after vitreous surgery (6 M) (1.21 ± 0.02 mm/s) significantly increased compared with BFV before surgery (0 M) (1.04 ± 0.10 mm/s) (p = 0.0061). BFV 1 year after vitreous surgery (1 Y) significantly increased (1.38 ± 0.02 mm/s) compared with BFV(6 M) (1.21 ± 0.02 mm/s) (p = 0.0235). FT was significantly greater in the ERM patients (351.7 ± 87.1 µm) than in the healthy subjects (158.9 ± 16.9 µm) (p = 0.0011). FT (6 M) significantly decreased (285.3 ± 36.9 µm) compared with FT before surgery (0 M) (351.7 ± 87.1 µm) (p = 0.0212). FT did not show significant differences between (6 M) and (1 Y). No significant correlation was found between BFV and FT before surgery. CONCLUSIONS: Perifoveal capillary BFV in patients with ERM was slower than that in the healthy subjects, and significantly improved after vitreous surgery as time progressed. It can be said that perifoveal capillary BFV is related to the development and improvement of ERM in the long term.

[Long-term outcome of vitrectomy combined with internal limiting membrane peeling for idiopathic macular holes].

PURPOSE: To elucidate the long-term outcome of internal limiting membrane (ILM) peeling on visual function during vitrectomy for idiopathic macular holes using scanning laser ophthalmoscope (SLO) microperimetry. DESIGN: Prospective uncontrolled study. PATIENTS AND METHODS: We studied 31 eyes (29 patients) with idiopathic macular holes. All patients underwent vitrectomy with ILM peeling. The SLO microperimetry was performed preoperatively, and once a year for 3 years postoperatively to detect scotomas in and around the macular holes, and both within and in close vicinity to the areas of ILM peeling. RESULTS: Closure of macular holes after one surgery was confirmed in all cases except for 2 with second surgery. The visual acuity by logarithmic minimum angle of resolution (logMAR) averaged 0.71 +/- 0.36 before surgery, 0.23 +/- 0.31 one year, 0.14 +/- 0.27 two years and 0.12 +/- 0.26 three years after surgery. There was significant improvement up to 2 years after the surgery. All scotomas detected before surgery in the holes, and 77.4% of those detected around the holes decreased gradually. No scotomas were detected in or around the area of ILM peeling either before or after surgery. CONCLUSION: ILM peeling in vitrectomy for idiopathic macular holes successfully improved visual acuity and did not influence retinal sensitivity in and around the area of ILM peeling. The scotomas detected in and around the holes before surgery gradually reduced or disappeared.

Macular microcirculation before and after vitrectomy for macular edema with branch retinal vein occlusion.

BACKGROUND: The changes of perifoveal capillary blood flow velocity (BFV), visual acuity, and retinal thickness after pars plana vitrectomy (PPV) have been unclear in patients with branch retinal vein occlusion (BRVO) and macular edema. METHODS: In a prospective study, PPV was performed on six eyes of six consecutive BRVO patients with macular edema (two women and four men; mean age: 66.3 +/- 5.0 years). Patients were examined preoperatively and 6 months postoperatively. BFV was measured by fluorescein angiography using a scanning laser ophthalmoscope and the tracing method. Macular thickness was examined by optical coherence tomography. Visual acuity was measured preoperatively and postoperatively, and data were converted to the logarithm of the minimum angle of resolution (logMAR). RESULTS: In all six treated eyes, the macular thickness decreased significantly compared with before PPV (464 +/- 98 microm versus 224 +/- 55 microm, P = 0.0082), mean BFV increased significantly compared with before PPV (1.14 +/- 0.14 mm/sec versus 1.46 +/- 0.21 mm/sec, P = 0.0013), and mean logMAR decreased significantly compared with before PPV (0.57 +/- 0.34 versus 0.17 +/- 0.21, P = 0.0036). CONCLUSIONS: PPV may improve perifoveal microcirculation and the visual prognosis in BRVO patients with macular edema.

Association between macular microcirculation and soluble intercellular adhesion molecule-1 in patients with macular edema and retinal vein occlusion.

BACKGROUND: In patients who have macular edema secondary to retinal vein occlusion, the role of vasoactive molecules such as growth factors and the influence of molecules related to leukocyte adhesion need to be investigated further. METHODS: A prospective study was performed to investigate the relations between perifoveal capillary blood flow velocity and the vitreous levels of vascular endothelial growth factor (VEGF) and soluble intercellular adhesion molecule-1 (sICAM-1) in patients with macular edema and retinal vein occlusion. Undiluted vitreous specimens were obtained from 11 eyes of 11 patients with macular edema (nine had branch retinal vein occlusion and two had central retinal vein occlusion). VEGF and sICAM-1 levels were measured by enzyme-linked immunoabsorbent assay. Before vitreous sampling, perifoveal capillary blood flow velocity was measured by fluorescein angiography with a scanning laser ophthalmoscope and the tracing method. The relations between perifoveal capillary blood flow velocity and the vitreous levels of VEGF and sICAM-1 were investigated. RESULTS: There was a significant correlation between perifoveal capillary blood flow velocity and the vitreous level of sICAM-1 (rho = -0.7303, p = 0.03). In contrast, there was no significant association between blood flow velocity and the vitreous level of VEGF (rho = -0.1458, p = 0.67). CONCLUSIONS: The vitreous level of sICAM-1 is associated with perifoveal capillary blood flow velocity in patients who have retinal vein occlusion and macular edema.

Pigment epithelium-derived factor and vascular endothelial growth factor in branch retinal vein occlusion with macular edema.

BACKGROUND: We investigated whether pigment epithelium-derived factor (PEDF) or vascular endothelial growth factor (VEGF) influence macular edema in patients with branch retinal vein occlusion (BRVO). This investigation aimed to clarify the influence of PEDF in the vitreous fluid on retinal vascular permeability in patients with macular edema secondary to BRVO. The findings were expected to be useful for the treatment of macular edema in BRVO patients. METHODS: This was a retrospective cross-sectional comparative case series. Thirty-three BRVO patients with macular edema and 24 control patients with nonischemic ocular diseases were enrolled. Retinal ischemia was evaluated by measuring the area of capillary nonperfusion on fluorescein angiography with Scion Image software. Macular edema was examined by optical coherence tomography. Vitreous fluid samples were obtained via pars plana vitrectomy, and the VEGF and PEDF levels were determined by enzyme-linked immunosorbent assay. RESULTS: The vitreous level of VEGF was significantly higher in BRVO patients than controls (P < 0.001). The vitreous PEDF level was significantly lower in BRVO patients than controls (P = 0.026). In BRVO patients, vitreous levels of PEDF and VEGF showed a significant negative correlation with each other (P < 0.001). Additionally, the vitreous VEGF level had a significant positive correlation (P < 0.001) and the vitreous PEDF level had a significant negative correlation (P < 0.001) with the nonperfused retinal area in BRVO patients. Furthermore, vitreous levels of VEGF and PEDF showed significant positive (P = 0.001) and negative (P = 0.014) correlations, respectively, with macular edema in BRVO patients. CONCLUSIONS: VEGF and PEDF may inversely influence retinal vascular permeability in patients with ischemic BRVO and macular edema. However, prospective validation will be needed to confirm these observations.

Aqueous humor levels of vasoactive molecules correlate with vitreous levels and macular edema in central retinal vein occlusion.

PURPOSE: Aqueous levels of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) are associated with the severity of macular edema in patients with central retinal vein occlusion (CRVO). We investigated whether aqueous and vitreous levels of these molecules were correlated in CRVO patients. METHODS: Aqueous and vitreous samples were obtained during cataract surgery and vitreous surgery from 17 patients (17 eyes) with CRVO and macular edema. The levels of VEGF and IL-6 in aqueous humor, vitreous fluid, and plasma were determined by enzyme-linked immunosorbent assay. RESULTS: The aqueous levels of VEGF and IL-6 were significantly correlated with the vitreous levels of these molecules (rho=0.8799, p=0.0004 and rho=0.8088, p=0.0012, respectively). Vitreous levels of VEGF and IL-6 were significantly higher in CRVO patients with retinal ischemia than in those without ischemia (p=0.0013 and p=0.0009, respectively), as were the aqueous levels of VEGF and IL-6 (p=0.0026, p=0.0120, respectively). Furthermore, both the aqueous and vitreous levels of VEGF and IL-6 were significantly correlated with the severity of macular edema (rho=0.7181, p=0.0041; rho=0.8260, p=0.0010; rho=0.5564, p=0.0260; and rho=0.6599, p=0.0039, respectively). CONCLUSIONS: Our results suggest that aqueous levels of VEGF and IL-6 may reflect the vitreous levels of these molecules. Measurement of VEGF and IL-6 in the aqueous humor may be clinically useful to assess the severity of macular edema in patients with CRVO.

[Strategy for treatment of diabetic retinopathy].

This paper conducts an analysis and discussion of the pathogenesis and treatment strategies for diabetic retinopathy, a major cause of blindness. Histological examination of experimental and biopsied material found that the pericyte necrosis and basement membrane thickening were responsible for sclerosis of retinal microvessels. The macrophages were noted in the pathogenesis of retinopathy. The cytokines of intraocular fluid were analyzed, and the vascular endothelial growth factor and intercellular adhesion molecule-1 were found to be closely related to retinopathy and macular edema. These findings suggest that the inflammation lead to the complex pathology of retinopathy. Anti-inflammatory drugs need to be included in the therapeutic strategy. The Diabetic Eye Notebook is an important source of information for patients who were lost to followup.

[Case of traumatic chiasmal syndrome].

BACKGROUND: Traumatic neuropathy of the optic chiasm is a rare finding which occurs after severe blunt head trauma. It is often accompanied by dysfunction of the pituitary gland and hypothalamus and called traumatic chiasmal syndrome. We report a patient with traumatic chiasmal syndrome caused by a severe traffic accident. CASE: A 25 year-old woman was referred for bitemporal visual field defects caused by a traffic accident two months before. Corrected visual acuity was 0.05 in the right eye and 1.2 in the left eye. Bilateral optic atrophy and relative afferent pupillary defect in the right eye were found. Magnetic resonance imaging revealed an enlarged optic chiasm. Computed tomography disclosed many fractures in the skull including the back wall of the sphenoid sinuses. She also suffered from diabetes insipidus and anosmia. CONCLUSION: Traumatic optic neuropathy of the optic chiasm is a rare condition which can be differentiated from neuropathy in the optic canal by considering the patterns of visual field defects and their accompanying signs.

[Five years of changes in diabetic eye notebooks].

PURPOSE: To compare 5 years transition of recognition, utilization, and purpose accomplishment in a diabetic eye notebook. METHODS: A questionnaire survey regarding the diabetic eye notebook was conducted with ophthalmologists and physicians in 10 prefectures of 9 areas in 2003 and 2008. RESULTS: The reply ratio of the questionnaire survey was 26% for ophthalmologists and 26% for physicians. The recognition and utilization ratio of diabetic eye notebook was significantly increased. The recognition and utilization ratio of diabetic eye notebooks in physicians was lower than in ophthalmologists. The improvement of cooperation of medical treatment, patients' understanding and consciousness of diabetic eye complications, and counter-measures of dropout by using diabetic eye notebooks have increased, but the significant difference was not. CONCLUSIONS: Although the recognition and utilization of diabetic eye notebooks has increased, there is still insufficient accomplishment of their purpose. There is a need for more elucidation of the importance of these notebooks not only for ophthalmologist but also for physicians and certified diabetes educators.

[Pathogenesis of macular edema associated with branch retinal vein occlusion and strategy for treatment].

We summarize the pathogenesis and the treatment strategy for macular edema in patients with branch retinal vein occlusion (BRVO), focusing on the role of the cytokines. Various cytokines are involved in the pathogenesis of macular edema associated with BRVO. When BRVO occurs, it leads to retinal ischemia that induces the production of cytokines such as vascular endothelial growth factor (VEGF) by retinal cells such as glial cells and vascular endothelial cells in the occluded region affected by anoxia. These cytokines interact with each other (cytokine network) and this results in impairment of the blood-retinal barrier and an increase of vascular permeability, considered important in the development of macular edema associated with BRVO. Treatment for this condition includes triamcinolone acetonide, anti-VEGF antibody, laser therapy and vitrectomy, all of which lead to the suppression of cytokine production. To manage macular edema associated with BRVO, it is important to control cytokine production with a combination of treatments.

Association of vitreous inflammatory factors with diabetic macular edema.

PURPOSE: To evaluate the association between vitreous inflammatory factors and the severity of diabetic macular edema (DME). DESIGN: Retrospective case-control study. PARTICIPANTS: Fifty-three patients with DME, 15 patients with nondiabetic ocular disease, and 8 diabetic patients without retinopathy. METHODS: Vitreous fluid samples were obtained during vitreoretinal surgery, and the levels of vascular endothelial growth factor (VEGF), intercellular adhesion molecule (ICAM)-1, interleukin (IL)-6, monocyte chemotactic protein (MCP)-1, and pigment epithelium-derived factor (PEDF) were measured by enzyme-linked immunosorbent assay. Multivariate analysis was performed to assess the association of these factors with the severity of DME. MAIN OUTCOME MEASURES: Vitreous fluid levels of inflammatory factors. RESULTS: Vitreous fluid levels of VEGF, ICAM-1, IL-6, and MCP-1 were significantly higher in patients with DME than in nondiabetic patients (P<0.05, all respectively) or diabetic patients without retinopathy (P<0.05, all respectively). In contrast, the PEDF level was significantly lower in patients with DME than in nondiabetic patients (P<0.05) or diabetic patients without retinopathy (P<0.05). Vitreous levels of VEGF, ICAM-1, IL-6, and MCP-1 were significantly higher in patients with hyperfluorescent DME than in those with minimally fluorescent DME (P = 0.0018, P = 0.0022, P = 0.0032, and P = 0.0053, respectively). Conversely, the vitreous level of PEDF was significantly lower in hyperfluorescent DME than in minimally fluorescent DME (P = 0.0134). Vitreous levels of VEGF, ICAM-1, IL-6, MCP-1, and PEDF were significantly correlated with the retinal thickness at the central fovea (P<0.0001, P<0.0001, P = 0.0282, P = 0.0009, and P = 0.0466, respectively). VEGF and ICAM-1 had a stronger influence on the severity of DME than the other factors (P = 0.0004 and P = 0.0372, respectively). CONCLUSIONS: Vitreous fluid levels of VEGF, ICAM-1, IL-6, MCP-1, and PEDF were related to retinal vascular permeability and the severity of DME. VEGF and ICAM-1 had a stronger influence than the other factors. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.

Vitreous levels of interleukin-6 and vascular endothelial growth factor in macular edema with central retinal vein occlusion.

OBJECTIVE: To investigate whether interleukin (IL)-6 or vascular endothelial growth factor (VEGF) influences macular edema in patients with central retinal vein occlusion (CRVO). DESIGN: Retrospective case-control study. PARTICIPANTS: Twenty-seven patients who had macular edema with CRVO and 16 patients with nonischemic ocular diseases (control group). METHODS: Retinal ischemia was evaluated by measuring the area of capillary nonperfusion using fluorescein angiography and the public domain Scion Image program, and macular edema was examined by optical coherence tomography. Vitreous fluid samples were obtained at pars plana vitrectomy. VEGF and IL-6 levels in vitreous fluid and plasma were determined with enzyme-linked immunosorbent assay kits. MAIN OUTCOME MEASURES: Vitreous fluid levels of IL-6 and VEGF. RESULTS: The vitreous fluid levels of VEGF (median: 435 pg/ml) and IL-6 (median: 51.2 pg/ml) were significantly higher in the patients with CRVO than in the control group (median: 62.4 pg/ml and 1.07 pg/ml, respectively; P = 0.0046 and P<0.0001, respectively). The vitreous fluid level of VEGF was significantly correlated with that of IL-6 (P = 0.0029). Vitreous fluid levels of both VEGF and IL-6 were significantly higher in patients with CRVO who had retinal ischemia than in those without ischemia (P<0.0001 and P = 0.0003, respectively). Vitreous fluid levels of VEGF and IL-6 were also significantly correlated with the severity of macular edema (P = 0.0014 and P = 0.0047, respectively). CONCLUSIONS: Both IL-6 and VEGF were elevated in the vitreous fluid of patients with ischemic CRVO and macular edema. VEGF may increase vascular permeability in patients with macular edema and CRVO, whereas IL-6 may also contribute by acting together with or via VEGF. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Management of type 2 diabetics requiring panretinal photocoagulation and cataract surgery.

PURPOSE: To evaluate the outcomes in patients with diabetic retinopathy and cataract who had panretinal photocoagulation (PRP) first and cataract surgery second in 1 eye and cataract surgery followed by PRP in the fellow eye. SETTING: Department of Ophthalmology, Saiseikai Kurihashi Hospital, Saitama, Japan. METHODS: Fifty-eight eyes of 29 patients with similar bilateral cataracts and severe nonproliferative or early proliferative diabetic retinopathy were randomly assigned for treatment with cataract surgery performed after PRP (PRP-first group) or before PRP (surgery-first group). Treatment was performed in the opposite order in the contralateral eye. The main outcome measure was best corrected visual acuity (BCVA) 12 months after surgery. The secondary outcome measures were the laser parameters, progression of retinopathy and macular edema, and aqueous flare intensity. RESULTS: The percentage of eyes with a BCVA of 20/40 or better was statistically significantly higher in the surgery-first group (96.6%) than in the PRP-first group (69.0%) (P = .012). The rate of the progression of macular edema was significantly decreased in the surgery-first group (P = .033). There was no significant difference between the 2 groups in the other outcome measures. CONCLUSION: Although the order in which PRP and cataract surgery were performed had no effect on postoperative retinopathy, the BCVA was better and the rate of the progression of macular edema was decreased in the surgery-first group.

[A case of nonarteritic anterior ischemic optic neuropathy with hypertension, diabetes mellitus, hyperlipidemia and severe stenosis of the internal carotid artery].

A 76 year-old man had had hypertension, diabetes mellitus and hyperlipidemia since 1985, and bruit in his left neck since 1993. He had abrupt decrease in left visual acuity on November 24, 2005, and visited an ophthalmologist. On November 28, his corrected visual acuity was 1.0 in the right and 0.1 in the left. The examination of optic fundi showed ear-side edema of the left optic disk. Fluorescence examination of the left optic fundus showed delay in early filling and later hyperfluorescence. Goldman visual field examination showed horizontal lower semiblindness. Since he did not complain of eye pain, his blood examination showed no reaction of inflammation, and he had hypertension, diabetes mellitus and hyperlipidemia, anterior ischemic optic neuropathy was diagnosed. The treatment with aspirin, alprostadil and prednisolone transiently improved the optic fundi and visual acuity, but his left visual acuity returned to 0.1. Carotid ultrasonography showed 95 percent stenosis in the left internal carotid artery. As there is no established treatment for ischemic optic neuropathy, the management of risk factors is most important.

Relationship of macular microcirculation and retinal thickness with visual acuity in diabetic macular edema.

PURPOSE: To assess perifoveal capillary blood flow velocity (BFV), capillary occlusion, and retinal thickness at the central fovea in diabetic patients with or without clinically significant macular edema; to examine the relationships of these variables with visual acuity (VA); and to identify their contributions to visual outcome and diabetic macular edema. DESIGN: Comparative cross-sectional prospective study. PARTICIPANTS AND CONTROLS: Diabetic patients with clinically significant macular edema (CSME) (n = 22), matched diabetic patients without CSME (n = 22), and healthy volunteers (n = 16). METHODS: Capillary BFV was measured by fluorescein angiography using a scanning laser ophthalmoscope and was analyzed by the tracing method. Severity of perifoveal capillary abnormalities was classified by the size and outline of the foveal avascular zone (FAZ) and extent of foveal capillary loss. Macular thickness was measured by optical coherence tomography. Each subject underwent a complete ophthalmic evaluation, and best-corrected VA (BCVA) was converted to the logarithm of the minimum angle of resolution scale. MAIN OUTCOME MEASURES: Relationship of perifoveal capillary BFV, capillary occlusion, and foveal thickness with VA. RESULTS: Best-corrected VA significantly differed among all 3 groups (P<0.0001). Best-corrected VA correlated negatively with BFV (r = -0.644, P<0.0001) among all subjects and positively with retinal thickness at the central fovea in diabetic patients with CSME (r = 0.640, P = 0.0013). There was a positive correlation between BCVA and severity in the size of the FAZ (r = 0.484, P = 0.0015), outline of the FAZ (r = 0.542, P = 0.0004), and extent of foveal capillary loss (r = 0.585, P = 0.0001) among all diabetic subjects. Multiple regression analysis showed that retinal thickness at the central fovea was the only variable that significantly predicted VA (standardized regression coefficient, 0.635; P = 0.0001). CONCLUSIONS: Best-corrected VA was associated with perifoveal capillary BFV, severity of perifoveal capillary occlusion, and retinal thickness at the central fovea in diabetic patients, but the greatest contributing factor was only the retinal thickness.

Influence of the signal-to-noise ratio on the accuracy of IOLMaster measurements.

PURPOSE: To evaluate the relationship between the sound-to-noise ratio (SNR) and the reliability of axial length (AL) measurements obtained with the IOLMaster (Carl Zeiss Meditec AG). SETTING: Department of Ophthalmology, Saiseikai Kurihashi Hospital, Saitama, Japan. METHODS: In a clinical prospective study, 216 consecutive eyes of 144 patients scheduled for cataract surgery were evaluated for the type and severity of cataract using the Lens Opacities Classification System III. Preoperative and postoperative AL measurements were performed with the IOLMaster. The preoperative SNR values were used to divide the eyes into 5 groups. The following were compared between the groups: preoperative logMAR best spectacle-corrected visual acuity (BSCVA), difference in AL between preoperatively and postoperatively, error in the postoperative predicted refraction, and type and severity of cataract. RESULTS: The preoperative logMAR BSCVA was significantly worse in eyes with an SNR <2 (P<.05). The AL was longer preoperatively than postoperatively in all groups, and there was a significant difference in the <2 SNR group and the 2 to <5 group (P<.05). There were no significant differences in the error in postoperative predicted refraction. The percentage of patients with P4 or worse posterior subcapsular cataract (PSC) increased significantly with a decrease in the SNR (P<.01). However, there was no correlation between nuclear color grade and the SNR. CONCLUSION: The SNR value was useful in confirming the good quality of AL readings taken with the IOLMaster, even though the SNR value correlated significantly with the preoperative logMAR BSCVA and PSC severity.