Trousseau's Syndrome With Severe Visual Loss As the Initial Symptom.

There are limited reports on patients with Trousseau syndrome, a condition characterized by hypercoagulability associated with malignant tumors, initially manifesting with reduced visual function. We present a case of a patient who experienced bilateral vision loss and was subsequently diagnosed with Trousseau's syndrome following examination and investigations. A 70-year-old man, undergoing chemotherapy for advanced pancreatic cancer, reported decreased visual acuity in both eyes. A dilated fundus examination revealed retinal pigment epithelial atrophy in the posterior pole and cotton-wool spots. Optical coherence tomography exhibited partial disruption of the ellipsoid zone in the parafoveal region, and full-field electroretinogram results were subnormal, although the macular retinal structure was preserved. Brain magnetic resonance imaging (MRI) detected occipital lobe infarction. Elevated coagulability markers, including D-dimer (5.5µg/mL), led to the diagnosis of Trousseau's syndrome. In cases where patients with malignant tumors present with profound visual loss, considering the possibility of Trousseau's syndrome and conducting assessments of brain function and coagulability is crucial for accurate diagnosis and appropriate management.

Retinopathy progression and the risk of end-stage kidney disease: results from a longitudinal Japanese cohort of 232 patients with type 2 diabetes and biopsy-proven diabetic kidney disease.

Objective: The predictive value of diabetic retinopathy on end-stage kidney disease (ESKD) has not been fully addressed in patients with type 2 diabetes and diabetic kidney disease. Research design and methods: We studied 232 patients with type 2 diabetes and biopsy-proven diabetic kidney disease who were screened for diabetic retinopathy during the 1 month of kidney biopsy. We examined the association between retinopathy progression and renal lesions. We used Cox regression analyses to explore the risk of ESKD adjusting for known risk demographic and clinical variables. We assessed the incremental prognostic value of ESKD by adding diabetic retinopathy to the clinical variables. Results: The diabetic retinopathy progression positively correlated with all scores of renal lesions, especially with the glomerular-based classification (r=0.41), scores of interstitial fibrosis (r=0.41) and diffuse lesion (r=0.48). During a median follow-up of 5.7 years, 114 patients developed ESKD. Adjusting for known risk factors of ESKD, the HR for ESKD (patients with no apparent retinopathy as a reference) were 1.96 (95% CI 0.62 to 6.17) for patients with mild non-proliferative diabetic retinopathy (NPDR), 3.10 (95% CI 1.45 to 6.65) for patients with moderate NPDR, 3.03 (95% CI 1.44 to 6.37) for patients with severe NPDR, and 3.43 (95% CI 1.68 to 7.03) for patients with proliferative diabetic retinopathy, respectively. Addition of the retinopathy grading to the clinical model alone improved the prognostic value (the global χ2 statistic increased from 155.2 to 164.5; p<0.001), which is an improvement equivalent to the addition of the renal lesion grading to the clinical model. Conclusions: Retinopathy progression appeared to be associated with renal lesions and the development of ESKD. Our findings suggest that diabetic retinopathy and kidney disease share the same magnitude of disease progression, and therefore diabetic retinopathy may be useful for prognosticating the clinical course for diabetic kidney disease.

Outcomes of microincision vitrectomy surgery with internal limiting membrane peeling for macular edema secondary to branch retinal vein occlusion.

PURPOSE: To evaluate the anatomic and functional effect of microincision vitrectomy surgery (MIVS) with internal limiting membrane (ILM) peeling for macular edema secondary to branch retinal vein occlusion (BRVO). METHODS: The medical records of 101 eyes of 101 patients who had undergone MIVS with ILM peeling for macular edema secondary to BRVO were studied. Patients were classified into ischemic and non-ischemic BRVO based on angiograph. The best-corrected visual acuity (BCVA) and central foveal thickness (CFT), determined by spectral domain optical coherence tomography, were evaluated at baseline and at 1, 3, 6, and 12 months postoperatively. RESULTS: Preoperative mean logarithm of the minimum angle of resolution (logMAR) BCVA ± standard deviation (SD) was 0.52±0.43 and mean CFT ± SD was 489.4±224.9 µm. Postoperative mean BCVA ± SD values were 0.41±0.35, 0.35±0.41, 0.29±0.36, and 0.25±0.41, and mean CFT values were 370.1±148.9, 327.5±157.5, 310.9±154.9, and 274.4±135.3 µm at 1, 3, 6, 12 months, respectively. The mean BCVA was significantly improved at 3, 6, and 12 months postoperatively (all P<0.05), and the mean CFT was significantly decreased at all postoperative follow-up time points (all P<0.05). At the 12-month postoperative evaluation, BCVA had improved by 0.2 logMAR units in 50 eyes (60.0%) with ischemic BRVO and in nine eyes (50.0%) with non-ischemic BRVO. Six eyes (6.0%) experienced recurrence or persistence of macular edema at 12 months postoperatively. CONCLUSION: MIVS with ILM peeling for macular edema secondary to BRVO is effective in improving visual acuity and foveal morphology with low recurrence of macular edema.

An evaluation of the effects of eyeball structure on ocular pulse amplitude in healthy subjects.

To evaluate the effects of eyeball structure on ocular pulse amplitude (OPA) measured using dynamic contour tonometer (DCT). In 86 eyes of 43 healthy subjects, we measured OPA and intraocular pressure (IOP) with DCT (DCT-IOP), IOP with Goldmann applanation tonometry (GAT-IOP), central corneal thickness (CCT), corneal thickness 2 mm (2 mmCT) and 4 mm (4 mmCT) apart from the center, corneal volume within a 3.5-mm radius from the corneal center, corneal curvature, anterior chamber depth, anterior chamber volume, and axial length (AL). OPA had a significant positive correlation with GAT-IOP (Pearson's r = 0.412, p < 0.001), DCT-IOP (r = 0.350, p < 0.001), and 4 mmCT (r = 0.244, p = 0.0231), and had a significant negative correlation with AL (r = -0.268, p = 0.0122). In a multiple linear regression analysis, AL and GAT-IOP were significantly associated with OPA. OPA measured with DCT is significantly influenced by several factors, such as IOP, peripheral corneal thickness (4 mmCT), and AL.

Temporally controlled targeted somatic mutagenesis in mouse eye pigment epithelium.

To generate temporally controlled site-specific somatic mutations in the mouse eye pigment epithelium, we generated a TRP1-Cre-ER(T2) transgenic mouse line that expresses the tamoxifen-dependent Cre-ER(T2) recombinase under the control of the tyrosinase-related protein 1 (TRP1) promoter. Cre-ER(T2) transcripts were readily detected in the retinal pigment epithelium (RPE), and tamoxifen treatment of adult TRP1-Cre-ER(T2) transgenic mice induced efficient excision of floxed DNA in patches of RPE cells, in numerous epithelial cells of the iris and ciliary body, and in very few cells of the neural retina. Importantly, no excision was detected in any cells in the absence of tamoxifen treatment. Thus, the TRP1-Cre-ER(T2) mouse line provides a powerful tool to study in vivo gene functions in the mouse eye pigment epithelium.

Pinguecula and diabetes mellitus.

PURPOSE: To assess the relationship between age and the incidence and severity of pinguecula in patients with diabetes mellitus, and to compare the grade of pinguecula between control subjects and patients with diabetes. METHODS: A total of 160 patients with type 2 diabetes aged 31 to 70 years (DM group) and 160 control subjects aged 31 to 70 years (control group) were enrolled. The grade of pinguecula at 2 locations (nasal and temporal) was assessed in all subjects by a grading system. RESULTS: There was an age-related increase in the grade of pinguecula in both the DMgroup (r = 0.52; P < 0.0001) and the control group (r = 0.51; P < 0.0001). The grade and prevalence of pinguecula were higher in the DM group than in the control group for pinguecula of the nasal conjunctiva (grade: P < 0.0001; and prevalence: 55.0% vs. 40.0%, P = 0.0072) and the temporal conjunctiva (grade: P < 0.0001; and prevalence: 54.4% vs. 40.0%, P = 0.0100). Multivariate logistic regression analysis revealed that age and diabetes were associated with an increased prevalence of nasal or temporal pinguecula (all P < 0.05). Diabetes mellitus was independently associated with the severity of pinguecula (nasal: odds ratio = 1.19; temporal: odds ratio = 1.22) after adjustment for age. CONCLUSIONS: This is the first assessment of the relationship between pinguecula and diabetes mellitus. Our results suggest that diabetes mellitus may be a factor associated with the development of pinguecula.

Bilateral choroidal detachment after cord blood stem cell transplantation in an adult patient with acute myeloid leukemia.

We report on bilateral choroidal detachment after a cord blood stem cell transplantation procedure. A 52-year-old woman had graft-versus-host disease 49 days after CBSCT for acute myeloid leukemia. She developed bilateral conjunctival chemosis and choroidal detachment 66 days after CBSCT. The annular choroidal detachment gradually increased in both eyes, with no improvement noted over the following month. At 106 days after CBSCT, the patient died from multiple organ failure. Graft-versus-host disease can be associated with bilateral choroidal detachment after CBSCT.

Conjunctivochalasis: associations with pinguecula in a hospital-based study.

PURPOSE: To assess the relationship between the prevalence and severity of conjunctivochalasis and pinguecula. METHODS: Cross-sectional, consecutive case study conducted at the university hospital of University of Tokyo Graduate School of Medicine. A total of 1061 patients aged from 1 to 94 years were enrolled. The grade and other parameters of conjunctivochalasis (classified into three locations: nasal, middle and temporal) and the grade of pinguecula located on the nasal or temporal conjunctiva were determined in all subjects. Patients were also divided into 5 or 10 age groups. RESULTS: The severity of conjunctivochalasis affecting the nasal and temporal bulbar conjunctiva was significantly correlated with the grade of pinguecula located on the nasal and temporal conjunctiva in each age group (p < 0.05). Pinguecula was independently associated with conjunctivochalasis (nasal: odds ratio [OR] = 1.44; temporal: OR = 1.43) after adjustment for age. CONCLUSION: This was the first assessment of the relation between the grade of conjunctivochalasis and pinguecula in a large consecutive series of patients. Our results suggest that the prevalence and severity of conjunctivochalasis are related to the presence of pinguecula.

Specific tear IgE in patients with moderate-to-severe autumnal allergic conjunctivitis.

BACKGROUND: Recently, a new commercial test for specific IgE based on immunochromatography (Immfast Check J1®) has been developed. We previously reported on the use of this kit for tear fluid samples during spring. In this study, we compared the level of specific IgE in tear fluid among patients with seasonal allergic conjunctivitis during spring or autumn and control subjects. METHODS: A nonrandomized, cross-sectional study was conducted in patients with moderate-to-severe allergic conjunctivitis occurring in spring (n = 56, spring group) or autumn (n = 52, autumn group), as well as in age- and sex-matched healthy control subjects (n = 50, control group). Levels of specific IgE for cedar pollen, cat epithelium and Dermatophagoides pteronyssinus were measured in tear fluid with the Immfast Check J1. RESULTS: Specific IgE scores for cedar pollen and D. pteronyssinus were significantly higher in the spring and autumn groups than in the control group (p < 0.0001). In the autumn group, the highest detection rate for a specific allergen was 96.2% for D. pteronyssinus, followed by cedar pollen (86.5%) and cat epithelium (25.5%). In the spring group, the highest detection rate was 98.3% for cedar pollen, followed by D. pteronyssinus (51.7%) and cat epithelium (19.0%). CONCLUSIONS: These results suggest that both house dust mite allergen and outdoor allergens such as cedar pollen can be causes of allergic conjunctivitis during both spring and autumn in Japan. The Immfast Check J1 provides rapid measurement of specific IgE in tear fluid, which allows easy diagnosis of allergic conjunctivitis in an outpatient setting.

Asymptomatic subconjunctival entrapment of a cilium.

We report an unusual case of asymptomatic subconjunctival entrapment of a cilium. A 64-year-old man presented with a 3 month history of a painless black line in the conjunctiva of the left eye, and slit-lamp examination revealed a cilium under the conjunctiva. The patient remained asymptomatic without conjunctival edema or hyperemia during a 2 week follow-up. To the best of our knowledge, this is the first report of an asymptomatic cilium inside the subconjunctival space.

Relation between total tear IgE and specific serum IgE in seasonal allergic conjunctivitis.

PURPOSE: Recently, a new commercial test for total tear immunoglobulin E (IgE), based on immunochromatography (Allerwatch), was developed. We examined the relation between the total IgE level in tears and specific serum IgE. METHODS: A prospective, nonrandomized, cross-sectional study was conducted in 35 patients with allergic conjunctivitis (allergic group), 30 age- and sex-matched healthy control subjects (control group), and 8 patients with epidemic keratoconjunctivitis. In all subjects, the total tear IgE score was determined with the Allerwatch test (0, 1, and 2), and serum levels of total IgE and specific IgE for 12 inhaled allergens were measured with the Phadezym PRIST and CAP-RAST systems, respectively. RESULTS: The total tear IgE-positive rate was significantly higher in the allergic group than in the control and epidemic keratoconjunctivitis groups (100.0% vs. 0.0% vs. 0.0%; P < 0.00001). In the allergic group, the total tear IgE score was significantly correlated with the log-transformed total serum IgE level (r = 0.61) and with the serum levels of IgE for cedar pollen (r = 0.35), house dust (r = 0.46), Dermatophagoides pteronyssinus (r = 0.49), and acarus (r = 0.36). Multivariate logistic regression analysis showed that the log-transformed total serum IgE level was the only significant predictor of the total tear IgE score (odds ratio = 1.85, P = 0.00008). CONCLUSIONS: The total tear IgE score, determined with the Allerwatch test, was correlated with the total and specific serum IgE levels. This rapid test is easy to perform, sensitive, and highly specific for the detection of ocular allergy on an outpatient basis.

Relationship between conjunctivochalasis and refractive error.

OBJECTIVES: To assess the relation between the prevalence and grade of conjunctivochalasis and refractive error and to compare the grade of conjunctivochalasis between myopic and hyperopic patients. METHODS: Consecutive patients aged from 3 to 94 years were chosen for this study. Exclusion criteria included a history of using contact lenses, ocular surgeries, infectious conjunctivitis, or corneal diseases. The age, gender, medical history, ocular history, the grade and other parameters of inferior conjunctivochalasis classified into three locations (nasal, middle, and temporal), and refractive error were determined in all subjects. Patients were divided into three groups as follows: a hyperopic group (≥0.0 D), an emmetropic group (<0.0 and ≥-2.0 D), and a myopic group (<-2.0 D). They were also divided into 10 groups according to age. One-way analysis of variance and the Scheffe multiple comparison test were used to compare the mean values among three groups. Relations among the variables were investigated by calculating Pearson correlation coefficients and partial correlation coefficients. RESULTS: A total of 1,110 patients were included in the study. In each age group, the mean grade of conjunctivochalasis was higher in hyperopic patients than in myopic patients. There were no significant differences in both the downward gaze- and digital pressure-dependent changes of conjunctivochalasis between the myopic and hyperopic groups. The severity of conjunctivochalasis affecting the nasal and temporal bulbar conjunctiva, and parameters such as the changes of conjunctivochalasis caused by downward gaze or digital pressure, were correlated with the refractive error, especially in patients over 40 years old (P<0.05). CONCLUSIONS: This was the first assessment of the relationship between refractive error and the grade of conjunctivochalasis in a large consecutive series of patients. Our results suggest that the prevalence and grade of conjunctivochalasis are dependent on refractive error, with hyperopia being an important risk factor for conjunctivochalasis.

Relationship between total tear and serum IgE in allergic conjunctivitis.

BACKGROUND: Recently, a new commercial test for total tear IgE based on immunochromatography (Allerwatch®) was developed. We examined the relationship between total tear and serum IgE levels with the Allerwatch test. METHODS: A nonrandomized cross-sectional study was conducted in 40 patients with allergic conjunctivitis, 35 age- and sex-matched healthy control subjects, and 6 patients with epidemic keratoconjunctivitis (EKC). The total tear IgE score was determined with the Allerwatch test (0, 1 and 2), and the serum total IgE level was measured by solid-phase immunoassay (Phadezym PRIST) in all subjects. RESULTS: Total tear IgE was assayed within 10 min of collection in all samples. The total tear IgE-positive rate was significantly higher in the allergic group than in the control and EKC groups (92.5 vs. 0.0 vs. 0.0%; p < 0.00001). Sensitivity and specificity were 0.925 and 1.000, respectively. The total IgE score and log (total serum IgE) were also higher in the allergic group than in the control and EKC groups [total IgE score: 1.48 ± 0.63 vs. 0.00 ± 0.00 vs. 0.00 ± 0.00, p < 0.00001; log (serum total IgE): 2.23 ± 0.50 vs. 0.80 ± 0.31 vs. 0.79 ± 0.37, p < 0.00001]. The total tear IgE score was significantly correlated with log (total serum IgE) in the allergic group (r = 0.712, p < 0.00001). CONCLUSIONS: These results show that this rapid test for the measurement of total tear IgE is easy to perform on an outpatient basis and may be helpful in the management of ocular allergy.

Rapid immunochromatographic measurement of specific tear immunoglobulin E in moderate to severe cases of allergic conjunctivitis with Immfast Check J1 in the spring.

PURPOSE: To evaluate whether Immfast Check J1, a new commercial immunochromatographic test for the measurement of specific immunoglobulin (Ig) E, could be used as a screening test for the diagnosis of allergic conjunctivitis. METHODS: A prospective, nonrandomized, cross-sectional study was conducted in 64 moderate to severe cases of allergic conjunctivitis (allergic group) and 44 age- and sex-matched healthy control subjects (control group). Specific IgE levels for cedar pollen, cat epithelium, and Dermatophagoides pteronyssinus were measured in tear fluid with the Immfast Check J1. RESULTS: Specific IgE levels in tear fluid could be assayed within 20 minutes in all subjects. The positive rate of specific IgE was significantly higher in the allergic group than in the control group (cedar pollen, 96.9% vs. 2.3%, P < 0.00001; cat epithelium, 23.4% vs. 0.0%, P = 0.00018; and D. pteronyssinus, 53.1% vs. 2.3%, P < 0.00001). Specific IgE scores were also significantly higher in the allergic group than in the control group (cedar pollen, P < 0.00001; cat epithelium, P = 0.03907; and D. pteronyssinus, P < 0.00001). CONCLUSIONS: These results suggest that Immfast Check J1 is a rapid and easy test for detection of allergen-specific IgE in tear fluid samples from patients with allergic conjunctivitis. The test is reliable and easy to perform on an outpatient basis.

Severity and determinants of pinguecula in a hospital-based population.

OBJECTIVES: Pinguecula is a relatively frequent disease; however, there have been no reports about the grade of pinguecula. We investigated the relationship between age and the prevalence and severity of pinguecula by using a grading system and compared the grade of pinguecula between men and women and between the nasal and temporal halves of the conjunctiva. METHODS: This was a prospective, randomized study of 1,040 patients aged 1 to 95 years, including 520 men and 520 age-matched women. The age, gender, medical history, ocular history, and grade of pingueculae located on the nasal and temporal conjunctiva were determined in all subjects. RESULTS: The prevalence of pinguecula increased dramatically with age. The mean grade was higher in male patients than in female patients for pingueculae located on both the nasal conjunctiva (P = 0.00072) and the temporal conjunctiva (P = 0.00035). However, there was no significant difference in the grade of pinguecula between the nasal and temporal conjunctiva. CONCLUSIONS: This was the first assessment of the grade of pinguecula in a large series of patients. Our findings strongly suggest that pinguecula is an age-dependent lesion that occurs from young adulthood onward. The present grading system should also be useful for future clinical studies of pinguecula.

Immunochromatographic assay for measurement of total IgE in tears, nasal mucus, and saliva of patients with allergic rhinoconjunctivitis.

OBJECTIVE: Measurement of total immunoglobulin E (IgE) is clinically important for the diagnosis of allergic diseases. The total serum IgE level is normally measured because of its widespread use and convenience, but little attention has been paid to the measurement of local IgE concentrations. We evaluated whether the measurement of local production of IgE in tears, saliva, and nasal mucus was useful for the diagnosis of allergic rhinoconjunctivitis. METHODS: A prospective, nonrandomized, cross-sectional study was conducted in 33 consecutive patients with seasonal allergic rhinoconjunctivitis (allergic group) and in 30 age- and sex-matched healthy control subjects (control group). The total IgE level was measured in tears, saliva, and nasal mucus from all subjects. Using a 4- or 5-point scale, symptoms (sneezing, rhinorrhea, nasal obstruction, ocular itching, and lacrimation) were assessed in each subject along with the activities of daily living (ADL) score and total symptom score for allergic conjunctivitis. RESULTS: Total IgE could be assayed within 10 minutes of collection in all samples. The scores for all symptoms were higher in the allergic group than in the control group (p < .00001). The IgE scores for tear fluid samples (p < .00001) and undiluted saliva (p = .00003) were significantly higher in the allergic group than in the control group. The total IgE score of tear fluid samples was strongly correlated with the severity of symptoms of allergic conjunctivitis, including ocular itching (r = 0.769, p < .00001), tearing (r = 0.560, p = .00035), and ocular symptom score (r = 0.329, p = .03452). On the contrary, the total IgE scores for both saliva and nasal mucus were correlated with the severity of rhinitis-related symptoms, including sneezing (saliva r = 0.897, p < .00001; nasal mucus r = 0.871, p = .00024), nose blowing (saliva r = 0.764, p < .00001; nasal mucus r = 0.829, p = .00080), and nasal obstruction (saliva r = 0.519, p = .00099; nasal mucus r = 0.745, p = .00429). The ADL score was correlated with the total IgE level in each specimen (tear r = 0.705, p < .00001; saliva r = 0.468, p = .00301; nasal mucus r = 0.479, p = .06816). CONCLUSIONS: These results suggest that local production of IgE is closely correlated with local allergic symptoms. This rapid test for the measurement of local IgE is easy to perform on an outpatient basis and may be helpful in the diagnosis of allergic rhinitis and conjunctivitis.

Contact lens-induced subconjunctival hemorrhage.

PURPOSE: To present the first detailed assessment of the clinical features of CL-induced subconjunctival hemorrhage and associated risk factors. DESIGN: Cross-sectional and case-control study of age-matched randomized groups. METHODS: A total of 45 CL wearers with subconjunctival hemorrhage aged 18 to 45 years (CL-Hemorrhage group), 200 age-matched healthy control subjects (non-CL group), and 200 age-matched CL wearers (CL group) were enrolled. The conjunctiva was divided into the following 8 equal areas: superior, superior/nasal, nasal, inferior/nasal, inferior, inferior/temporal, temporal, and superior/temporal. The site of hemorrhage, the grade, and other parameters of conjunctivochalasis at 3 locations (nasal, middle, and temporal), and the grade of pinguecula on the nasal or temporal conjunctiva were determined in all subjects. RESULTS: Typically, subconjunctival hemorrhage affected 1 or 2 regions of the temporal conjunctiva. The grade of conjunctivochalasis and pinguecula was higher in both the affected and unaffected eyes of the CL-Hemorrhage group than the non-CL and CL groups (all P < .00001). The effect of downward gaze or digital pressure on the extent of conjunctivochalasis was more marked in the CL-Hemorrhage group and superficial punctate keratitis was more common (all P < .00001). Multivariate logistic regression analysis of variables revealed that the presence of conjunctivochalasis and pinguecula were associated with an increased risk of CL-induced subconjunctival hemorrhage (all P < .05). CONCLUSIONS: These results suggest that the major risk factors for CL-induced subconjunctival hemorrhage are conjunctivochalasis and pinguecula.

Spatial and temporal regulation of Wnt/beta-catenin signaling is essential for development of the retinal pigment epithelium.

Wnt/beta-catenin signaling is highly active in the dorsal retinal pigment epithelium (RPE) during eye development. To study the role of Wnt/beta-catenin signaling in the RPE development we used a conditional Cre/loxP system in mice to inactivate or ectopically activate Wnt/beta-catenin signaling in the RPE. Inactivation of Wnt/beta-catenin signaling results in transdifferentiation of RPE to neural retina (NR) as documented by downregulation of RPE-specific markers Mitf and Otx2 and ectopic expression of NR-specific markers Chx10 and Rx, respectively. In contrast, ectopic activation of Wnt/beta-catenin signaling results in the disruption of the RPE patterning, indicating that precise spatial and temporal regulation of Wnt/beta-catenin signaling is required for normal RPE development. Using chromatin immunoprecipitation (ChIP) and reporter gene assays we provide evidence that Otx2 and RPE-specific isoform of Mitf, Mitf-H, are direct transcriptional targets of Wnt/beta-catenin signaling. Combined, our data suggest that Wnt/beta-catenin signaling plays an essential role in development of RPE by maintaining or inducing expression of Mitf and Otx2.

Clinical and functional findings in crystalline retinopathy.

BACKGROUND: Crystalline retinopathy is an infrequently encountered disorder characterized by reflective retinal crystalline deposits. The clinical findings of seven patients with crystalline retinopathy are documented. METHODS: Clinical features of crystalline retinopathy were studied retrospectively in seven patients, three of whom were followed up for 2 to 5 years. RESULTS: Six patients had a similar fundus appearance, that is, the reflective yellow deposits located mainly in the deep retina with retinal pigment epithelium atrophy throughout the posterior pole and mid-peripheral retina and with choriocapillaris atrophy at the posterior pole. However, the results from electroretinogram responses were markedly variable. Two of the patients showed marked electroretinogram functional impairment. In addition, other sibling patients only 3 years apart in age had different degrees of disease expression. CONCLUSION: There is considerable variability in functional manifestations among patients with crystalline retinopathy, even in intrafamilial cases.

Retinal dystrophy resulting from ablation of RXR alpha in the mouse retinal pigment epithelium.

Vitamin A (retinol) actions in eye development are mediated by retinoic acid receptors (RARs and RXRs). Using the Cre/loxP system, we have selectively ablated RXR alpha in the retinal pigment epithelium (RPE), a cell monolayer critically involved in visual retinoid renewal and phagocytosis of photoreceptor outer segments. In the mutant (RXR alpha (rpe-/-)) mice, RPE cells are morphologically and functionally abnormal and display decreased expression of proteins involved in the visual retinoid cycle, namely RPE65, CRALBP, and RGR. RXR alpha (rpe-/-) mice also show alterations of photoreceptor cells including: 1) decrease in their number; 2) outer segment shortening and disorganization, and 3) reduced light responses in electroretinograms. These results indicate that RXR alpha is required for normal maturation of the RPE, which is known to play essential roles in photoreceptor cell function and survival, and point to a possible involvement of RXR alpha signaling pathways in the RPE in human retinal diseases.