Retinal Hypopigmentation Research Articles

BOLD Contrast Response Characteristics of Aberrant Voxels with Bilateral Visual Population Receptive Fields in Human Albinism.

Albinism is an inherited disorder characterized by disrupted melanin production in the eye, and often in the skin and hair. This retinal hypopigmentation is accompanied by pathological decussation of many temporal retinal afferents at the optic chiasm during development, ultimately resulting in partially superimposed representations of opposite visual hemifields in each cortical hemisphere. Within these aberrant regions of hemifield overlap, individual voxels have been shown to have bilateral, dual population receptive fields (pRFs) responding to roughly mirror-image locations across the vertical meridian. Nonetheless, how these two conflicting inputs combine to determine a voxel's response to image contrast is still unknown. To address this, we stimulated the right and left hemifields with separately controlled sinusoidal gratings, each having a variety of contrasts (0, 8, 20, 45, 100%), and extracted voxel-wise BOLD response amplitudes to each contrast combination in visual areas V1-V3. We then compared voxels' responses to each hemifield stimulated individually with conditions when both hemifields were stimulated simultaneously. We hypothesized that simultaneous stimulation of the two pRF components will result in either a suppressive or facilitative interaction. However, we found that BOLD responses to simultaneous stimulation appeared to reflect simple summation of the neural activity from the individual hemifield conditions. This suggests that the superimposed opposite hemifield representations do not interact. Thus, dual pRFs in albinism likely reflect two co-localized, but functionally independent populations of neurons each of which respond to a single hemifield. This finding is commensurate with psychophysical studies which have shown no clear perceptual interaction between opposite visual hemifields in human albinism.

Chronic Serous Chorioretinopathy: A Case Study

Introduction Chronic central serous chorioretinopathy (CSCR) is characterized by persistent subretinal fluid that disrupts the outer layers of the retina and may lead to complications such as: outer retinal atrophy, increased risk of choroidal neovascularization (CNVM) and the potential for permanent vision loss. This report describes the clinical features of chronic CSCR. Case Presentation A 73-year-old male with a history of systemic steroid and inhaler use presented for a routine eye exam without visual complaints. Examination findings included normal visual acuity in both eyes and multiple areas of retinal hyper and hypopigmentation along the arcades with no macular involvement in the right eye; the left eye was unremarkable. Fundus photography and optical coherence tomography showed localized areas of outer retinal disruption and thinning near the optic nerve head and along the corresponding retinal areas of irregular pigmentation in the right eye; the left eye was unremarkable. Discussion In chronic CSCR, structural changes in the retina can lead to retinal dysfunction and permanent vision loss. Treatment options for chronic CSCR include photodynamic therapy, intravitreal anti-vascular endothelial growth factor therapy, or systemic steroid receptor blockers. Visual prognosis varies depending on the severity of the disease, age of onset, risk of CNVM and the degree of outer retinal degeneration. Conclusion Patients with chronic CSCR are at risk for permanent vision loss. The structural changes in the outer retina also increase the risk for CNVM. Hence, it is important that patients with chronic CSR receive regular eye examinations and are educated on the role of regular Amsler grid testing.

Ocular manifestations in Koolen–de Vries syndrome: an international study

ObjectivesKoolen–de Vries Syndrome (KdVS) is a rare multisystem neurodevelopmental disorder. Ocular manifestations, including strabismus, ptosis, and hyperopia, have been reported in KdVS patients, but detailed clinical data are limited. This study aims to investigate the already known ocular malformations and their frequency while uncovering novel ocular associations. MethodsThis was an international cross-sectional study. An anonymous questionnaire was sent to 237 KdVS patients registered in the GenIDA database. The questionnaire inquired about demographic data, ocular symptoms, findings reported by ophthalmologists, and ophthalmologic surgical interventions. The main outcome measures included ocular findings and surgical interventions. ResultsSixty-seven respondents worldwide completed the questionnaire, most (n = 53; 79%) under 18 years of age. Ophthalmologic abnormalities, noted in 79% of patients, included refractive errors (n = 35; 52.2%), strabismus (n = 23; 34.3%), amblyopia (n = 13; 19.5%), and eyelid ptosis (n = 9; 13.4%). Lacrimal disorders were present (n = 6; 9.0%), as were retinal findings (n = 7; 10.4%), including retinal hyperpigmentation or hypopigmentation (n = 4; 7.5%), Sjögren's pigment epithelial reticular dystrophy (n = 1; 1.5%), and macular chorioretinal coloboma (n = 1; 1.5%). Other manifestations included ocular surface disorders (n = 5; 7.5%), cataracts (n = 3; 4.5%), Brown syndrome (n = 1; 1.5%), glaucoma (n = 1; 1.5%), cerebral visual impairment (n = 1; 1.5%), and optic atrophy (n = 1; 1.5%). Fourteen patients (20.8%) had undergone surgical interventions. ConclusionsKdVS is associated with various ophthalmic findings, such as amblyopia, refractive errors, strabismus, and eyelid ptosis. We describe, for the first time, a high rate of nasolacrimal disorders and retinal abnormalities consisting mainly of pigmentary findings, including a rare case of Sjögren's pigment epithelial reticular dystrophy. A comprehensive ophthalmic evaluation is therefore recommended for all KdVS patients at initial diagnosis or at 4–6 months of age for diagnosed newborns.

Effectiveness of refractive error correction for people with oculocutaneous albinism in South Indian population

Introduction: Albinism comes from ‘albus’, the Latin word meaning white, and refers to a group of hereditary disorders wherein the biosynthesis of the pigment melanin is absent or reduced. Oculocutaneous albinism (OCA) is a heterogeneous and autosomal recessive disorder that involves a lack of pigment in the skin, hair, and eyes, and is associated with ocular and visual defects such as photophobia, strabismus, nystagmus and low vision. Materials and Methods: This was a cross sectional descriptive community based study conducted at a tertiary care medical college hospital. The Department of Ophthalmology enrolled 39 subjects satisfying the inclusion criteria. The diagnostic criteria for OCA patients included in the study, were those having ocular features of iris transillumination and retinal hypopigmentation in addition to depigmentation of the skin, hair and nails. Results: 39 patients with OCA were included, mean age 20 years. The largest proportion of participants (40%) included those between 16 and 25yrs. Using World Health Organization classification based on best corrected distance visual acuity, 8%, 70%, 15% and 7% of 78 eyes had normal vision, moderate VI, severe VI and blindness respectively. Conclusion: There is high prevalence of refractive, non-refractive and mixed ophthalmic disorders among albinos. There was significant improvement in visual acuity and function following optical correction and alignment in people with albinism, despite overall subnormal acuity. Refractive correction should be encouraged for people with albinism.

The Tietz syndrome associated with cardiac malformation: a case report with literature review

BackgroundTietz syndrome is a very rare clinical entity characterized by the association of profound bilateral congenital sensorineural deafness and generalized hypopigmentation of skin, eyes, and integuments (snow white appearance). It is an autosomal dominant syndrome due to a mutation in the melanocyte inducing transcription factor (MITF) gene. The association of a heart malformation has never been reported in this syndrome.Case presentationWe report two cases of two cousins aged 5 years and 20 months respectively with a history of first degree consanguineous parents. Both girls presented with diffuse hypopigmentation of the skin, blond hair, blue eyes, and bilateral diffuse retinal hypopigmentation at ocular fundus exam. Bilateral profound sensorineural hearing loss was confirmed by auditory brainstem response in both cases. Echocardiography revealed a cardiac malformation such as interventricular communication in the older cousin and interatrial communication in the younger cousin. The family investigation did not reveal a similar case among ancestors. The diagnosis of Tietz syndrome was based on clinical criteria and pedigree. The older cousin underwent a total optical correction and a right unilateral cochlear implantation followed by speech therapy with a satisfactory result after a follow-up of two years. Unfortunately, the little cousin died following a head trauma.ConclusionsTietz syndrome is a rare autosomal dominant genetic disorder, characterized by generalized albinism with bilateral profound hearing loss. It results from a nontruncating mutation in the basic domain of in the MITF gene. Its management must include, in addition to hearing and ophthalmic rehabilitation, the research and treatment of cardiac malformations which may be life-threatening.

Biallelic P4HTM variants associated with HIDEA syndrome and mitochondrial respiratory chain complex I deficiency

We report a patient with profound congenital hypotonia, central hypoventilation, poor visual behaviour with retinal hypopigmentation, and significantly decreased mitochondrial respiratory chain complex I activity in muscle, who died at 7 months of age having made minimal developmental progress. Biallelic predicted truncating P4HTM variants were identified following trio whole-genome sequencing, consistent with a diagnosis of hypotonia, hypoventilation, intellectual disability, dysautonomia, epilepsy and eye abnormalities (HIDEA) syndrome. Very few patients with HIDEA syndrome have been reported previously and mitochondrial abnormalities were observed in three of four previous cases who had a muscle biopsy, suggesting the possibility that HIDEA syndrome represents a primary mitochondrial disorder. P4HTM encodes a transmembrane prolyl 4-hydroxylase with putative targets including hypoxia inducible factors, RNA polymerase II and activating transcription factor 4, which has been implicated in the integrated stress response observed in cell and animal models of mitochondrial disease, and may explain the mitochondrial dysfunction observed in HIDEA syndrome.

A novel BLOC1S5-related HPS-11 patient and zebrafish with bloc1s5 disruption.

Hermansky-Pudlak Syndrome (HPS) cases present with a variable degree of OCA and bleeding tendency. HPS is categorized into eleven types based on eleven causative genes, and disease severity varies among different types. By whole-exome sequencing performed on a family trio and Sanger sequencing of candidate variants, we identified a novel homozygous variant (NM_201280.3: c.181delC, p.Val61*) in BLOC1S5 in the patient who presents OCA and mild bleeding diathesis, and his healthy parents are heterozygous carriers. The variant can be considered pathogenic based on the guideline American College of Medical Genetics and Genomics, and the patient is proposed to be affected with HPS-11. In this study, we also explored bloc1s5 in zebrafish. bloc1s5 mRNA can be detected during early development of zebrafish. bloc1s5 knockdown zebrafish present with retinal hypopigmentation, thrombocytes loss and pericardial edema, and dll4/notch1 signaling and vascularintegrity signaling are down-regulated at mRNA level in bloc1s5 morphants. The data from the first HPS-11 patient in Chinese population expand phenotypic and genotypic spectrum of HPS-11. Disruption of bloc1s5 in zebrafish recapitulates HPS-11-like phenotypes, and the potential signaling pathways associated with bloc1s5 are proposed. Altogether, this study may facilitate genetic counseling of HPS and investigation about BLOC1S5.

Incidence and Progression of Nongeographic Atrophy in the Comparison of Age-Related Macular Degeneration Treatments Trials (CATT) Clinical Trial

Retinal hypopigmentation and hyperpigmentation are precursors of geographic atrophy (GA). Incidence and progression to GA in eyes treated with anti-vascular endothelial growth factor for neovascular age-related macular degeneration (nAMD) have not been investigated. To determine the incidence and progression of non-GA (NGA) and associated risk factors. This study is a post hoc analysis of a cohort study within the Comparison of Age-Related Treatments Trials (CATT) clinical trial. Participants were recruited February 20, 2008, through December 9, 2009; released from protocol follow-up and treatment after 2 years; and recalled from March 14, 2014, through March 31, 2015. Data analyses were conducted from January 11, 2019, through November 27, 2019. Participants were randomized to ranibizumab or bevacizumab for (1) 2 years of monthly or as-needed injections or (2) monthly injections for 1 year and as-needed injections the following year. Participants were treated according to best medical judgement thereafter. Incidence of nAMD-associated NGA (hypopigmentation and hyperpigmentation in color images) and progression; adjusted risk ratios (aRR) for baseline characteristics. Among 1107 participants, risk of NGA was 35% (391 eyes), 59% (246 eyes), and 81% (122 eyes) at 1, 2, and 5 years, respectively. Risk factors for NGA included worse visual acuity (20/200-20/320: aRR, 1.74 [95% CI, 1.24-2.43], compared with ≤20/40; P = .006), larger neovascularization area (>4 disc areas: aRR, 1.31 [95% CI, 1.01-1.71], compared with ≤1 disc areas; P = .007), switched drug regimen (aRR, 1.28 [95% CI, 1.06-1.54], compared with as-needed injections; P = .02), and single-nucleotide variants Age-Related Maculopathy Susceptibility 2 (ARMS2) (TT variant: relative risk [RR], 1.53 [95% CI, 1.22-1.93]; P = .001) and HtrA Serine Peptidase 1 (HTRA1) (AG variant: RR, 1.23 [95% CI, 1.01-1.48]; AA variant: RR, 1.51 [95% CI, 1.20-1.91]; P = .002). Sub-retinal pigment epithelium thickness was protective (>275 μm: aRR, 0.59 [95% CI, 0.46-0.75], compared with ≤75 μm; P < .001). Among 389 eyes with NGA by 2 years and subsequent color images, risk of progression to GA was 29%, 43%, and 50% at 1, 3, and 4 years, respectively. Risk factors for progression to GA included worse visual acuity (20/200-20/320: aRR, 2.75 [95% CI, 1.54-4.93], compared with ≤20/40; P < .001), worse fellow-eye visual acuity (<20/40: aRR, 1.77 [95% CI, 1.12-2.79], compared with ≥20/40; P = .01), fellow-eye GA (aRR, 1.71 [95% CI, 1.06-2.75]; P = .03), and pseudodrusen in either eye (aRR, 1.65 [95% CI, 1.17-2.34]; P = .005). Subretinal fluid was associated with a decreased risk of progression (aRR, 0.42 [95% CI, 0.28-0.63]; P < .001). In this study, after 2 years of protocol-guided anti-vascular endothelial growth factor treatment for nAMD, more than half of the eyes in the study developed NGA in the location of nAMD. After 3 additional years of regular care, half of them progressed to GA. ClinicalTrials.gov Identifier: NCT00593450.

Albinism: An Underdiagnosed Condition

Albinism is a clinically and genetically heterogeneous condition characterized by variable degrees of hypopigmentation extending from a complete absence of pigmentation to normal pigmentation and by ophthalmological anomalies, including nystagmus, foveal hypoplasia, chiasmatic misrouting of the optic nerves, iris transillumination, retinal hypopigmentation, and reduced visual acuity. Nineteen genes are involved in the oculocutaneous, ocular, and syndromic (Hermansky-Pudlak Syndrome and Chediak-Higashi Syndrome) forms of the disease and in the more recently characterized foveal hypoplasia, optic nerve decussation defects and anterior segment dysgenesis (Arveiler et al., 2017; Montoliu et al., 2014).

Concentric Macular Rings Sign in Chediak-Higashi Syndrome

A 5-year-old boy was referred with reduced visual acuity (20/40 in both eyes) and nystagmus. Medical history was relevant for recurrent infections and bleeding tendency. Color images showed retinal hypopigmentation with a peculiar concentric macular rings sign (Fig A, white dashed boxes). Infrared reflectance imaging demonstrated a lack of the classic “bow-tie” foveal reflex (Fig B). Spectral domain-OCT revealed bilateral grade 3 foveal hypoplasia (Fig C). Peripheral blood analysis disclosed giant azurophilic inclusions in the neutrophils which are the hallmark of Chediak-Higashi syndrome (Fig D). Concentric macular rings sign is a distinctive feature of foveal hypoplasia and aids the diagnosis, especially in patients in which OCT cannot be performed. (Magnified version of Fig A-D is available online at www.aaojournal.org).

Bilateral symmetrical nasal retinal hypopigmentation associated with iris heterochromia: A case report

Bilateral symmetrical nasal retinal hypopigmentation associated with iris heterochromia: A case report

Ocular Manifestations Encountered in Albinos Living in Libreville: Epidemiological and Clinical Aspects

Introduction: Albinism is a rare hereditary genetic disorder, characterized by melanogenesis disorders associated to varying degrees of cutaneous, atrial and visual disorders. In Libreville, no data on the subject is available. Purpose: To describe the ocular manifestations found in albinos living in Libreville. Patients and methods: This was a cross-sectional and descriptive study that took place in Libreville during a year from and that concerned 43 albinos. The inclusion criteria were any albino with oculocutaneous albinism present in Libreville who has agreed to participate in the investigation. The variables studied were age, sex, visual acuity, ametropia, iris color, iris transillumination, strabismus, nystagmus, torticollis, amblyopia, optic disc, photophobia, foveal hypoplasia and retinal hypopigmentation. Data was collected and analyzed using Epi infoTM 7.2.0.1 CDC and IBM&#174 SPSS&#174 V21 Statistic software. Results: The mean age was 21.2 ± 17 years with a (F/M) ratio of 0.53. Visual acuity by far without correction (AVLCSC) < 3/10 was found in 88.4% of cases. Astigmatism, two-tone iris and torticollis were found respectively in 52.7%, 51% and 26% of cases. Retinal hypopigmentation and foveal hypoplasia were noted in 65.1% and 86% of cases. Divergent strabismus was noted in 71.4% and small and pale papilla in 95.1% of cases. Photophobia, iris transillumination, nystagmus and amblyopia were noted in 100% of cases. Conclusion: The ocular manifestations encountered in our series are similar to those described in literatures.

Mild form of oculocutaneous albinism type 1: phenotypic analysis of compound heterozygous patients with the R402Q variant of the TYR gene

AimOculocutaneous albinism type 1 (OCA1) is due to TYR mutations. c.1205G>A/p.Arg402Gln (R402Q) is a thermosensitive variant of the TYR gene that has been reported to be responsible for mild forms...

The important role of OCT in the diagnosis of Oculocutaneous albinism

PurposeOculocutaneous albinism (OCA) is a group of genetic diseases with an autosomal dominant pattern. It affects skin, hair and eyes, leading in an hypopigmentation of all these organs. In ophthalmology we can observe a low visual acuity, photophobia, nystagmus, foveal hypoplasia and retinal hypopigmentation. The hypopigmentation may also affect the iris with a characteristic iridian translucence. The disease is also associated with chiasm alterations.MethodssWe present the case of a 40 year old patient that was referred to our service to confirm the diagnosis of oculocutaneous albinism. The patient presents a severe hypopigmentation of the skin and hair. She also referred a low visual acuity since birth. She didn't presented family antecedents, or personal ophthalmologic history.ResultsThe best corrected visual acuity (BCVA) was 0.1 in both eyes. The patient presented horizontal nystagmus and iridian translucence. The fundus examination revealed an important retinal atrophy that showed the choroidal circulation.The optical coherence tomography (OCT) revealed a foveal hypoplasia, atrophy in the epithelial retinal epithelium.ConclusionsIn the patients that the diagnosis of oculocutaneous albinism is not clear, the use of an objective complementary test may be determinant before the genetic diagnosis. This case shows the utility of macular OCT to guide the molecular diagnosis.

Prevalence of Ocular Findings in Patients with Vitiligo

Background: Vitiligo involves 1% of the population and is equally seen in all races and in both genders. It is a multifactorial polygenic disorder, although various hypotheses have been proposed including autoimmunity, viral infection, biochemical, neural and oxidant/antioxidant theories (oxygen radical species), yet the exact mechanism of the disease has not been yet established. Objectives: To evaluate the prevalence of ocular findings in patients with vitiligo and reveal risk factors or possible associations that might increase the risk of ocular manifestations. Patients and Methods: In this cross-sectional study, 92 patients previously diagnosed as cutaneous vitiligo referred to the dermatology clinic of Rassoul Akram Hospital from April 2007 to September 2008, were examined for ocular abnormalities. The data of the patients including age, gender, duration of vitiligo, positive family history, association with autoimmune diseases, and anatomic distribution of depigmented macules were recorded. Next, an ophthalmologist at the hospital’s ophthalmology clinic examined the patients to detect depigmentation of eyelids, poliosis and signs of uveitis as well as signs of retinal atrophy or hypopigmentation by a direct ophthalmoscope. Corneal sensation and intraocular pressure (IOP) were evaluated to rule out infection and glaucoma in patients with uveitis. All recorded data were analyzed by the Social Sciences Statistical Software (SPSS version 15) using Chi-square tests and t-test. Results: This cross-sectional study included 92 patients (47 male and 45 female) with mean age of 32.1 ± 13.16 years (ranging from nine to 61 years of age). Mean duration of vitiligo was 10.84 ± 10.17 years. The most common distribution of the lesions was on the upper limbs (60.8%) and the least was on the genital region (10.8%). Positive family history was found in 26 (28.3%) patients. Diabetes and Hypothyroidism were found in 10 (10.86%) and 9 (9.87%) patients, respectively. Ocular problems were discovered in 19 (20.7%) patients with mean age of 41.26 ± 10.7 years, including uveitis in 10 (10.9%), optic atrophy in 4 (4.3%) and retinal hypopigmentation in 5 (5.4%) patients. Mean age of cases with positive ocular findings was significantly higher than those without ocular findings (29.6 ± 12.7 years, P < 0.0001). Mean duration of vitiligo was significantly longer in patients with positive ocular findings than in those without ocular problems (8.84 ± 9.08 years, P < 0.0001). No statistical correlation was found between sex and ocular findings (P > 0.05). Ocular findings were statistically more in patients with positive family history of vitiligo (P = 0.001) and with associated autoimmune diseases (P = 0.01). No significant association was found between anatomical distribution of depigmented macules and ocular findings (P > 0.05). Conclusions: Ocular findings are important and assessable in patients with vitiligo. Older age and duration of vitiligo can increase the risk of ocular abnormalities and patients with positive family history and autoimmune disorders should be prioritized for screening.

Retinal Arteriolar Wall Signs and Early Age-Related Macular Degeneration: The Singapore Malay Eye Study

To determine whether retinal arteriolar wall signs are associated with early age-related macular degeneration (AMD). Population-based cross-sectional study. The Singapore Malay Eye Study (SiMES) is a population-based eye survey including 3,280 (78.7% response) persons aged 40 to 80 years. Retinal arteriolar wall signs and AMD were assessed from photographs by trained technicians, according to standardized protocols. Data on major cardiovascular risk factors and blood pressure were collected. Of the 3,280 participants, 2,541 had photographs that were gradable for both AMD and retinal arteriolar wall signs. Early AMD was present in 76 subjects. There were no significant associations of any retinal arteriolar wall signs with early AMD. For specific AMD signs, retinal arteriolar wall opacification was associated with presence of soft distinct drusen (odds ratio [OR] 1.58, 95% confidence interval [CI]: 1.06, 2.35). This association was most significant among non-statin users (OR 1.90, 95% CI: 1.23, 2.93). Focal arteriolar narrowing was associated with retinal hypopigmentation (OR 1.67, 95% CI: 1.02, 2.73). Arteriovenous nicking was not associated with soft drusen (OR 0.89, 95% CI: 0.51, 1.57), hyperpigmentation (OR 0.49, 95% CI: 0.22, 1.08), or hypopigmentation (OR 0.86, 95% CI: 0.46, 1.61). Retinal arteriolar wall signs are not consistently associated with early AMD. We report a new association of retinal arteriolar wall opacification and the presence of soft drusen. This finding could support the hypothesis of a link between lipids and drusen formation.

Ocular Findings in a Case of Trisomy 18 With Variant of Dandy-Walker Syndrome

Trisomy 18 is the second most common chromosomal syndrome and has multiple dysmorphic features. However, ocular findings in trisomy 18 are rarely reported. Retinal folds are the most common ocular finding described to date, although retinal hypopigmentation, dysplasia, and areas of hemorrhage and gliosis are also found in trisomy 18. Dandy-Walker syndrome is a brain malformation that has been reported in association with numerous chromosomal abnormalities, although it has rarely been reported in association with trisomy 18. Here, we present a case of trisomy 18 with ocular pathology and variant of Dandy-Walker syndrome, a combination that has not previously been reported.

Segmental pigmentation disorder

There is little published information about segmental hypo- and hyperpigmentation pigmentation disorder (SegPD) although it is a relatively common problem in paediatric dermatology. To define the spectrum of disease, clinical presentation and associations in cases of SegPD and to clarify further the terminology in defining patterned hypo- and hyperpigmentation in children. This was a retrospective review of cases in an academic paediatric dermatology practice. Thirty-nine patients referred for dermatological evaluation were diagnosed with SegPD. Demographic and clinical features, and distribution and frequency of extracutaneous abnormalities were measured. Twenty female and 19 male patients were included in the study; 33 out of the 39 were referred specifically for a pigmentation abnormality. The mean age at onset was 3·4 months (median age 0·25 months). Family history was positive in two patients. Most (30/39; 77%) had segmental hyperpigmentation whereas nine of 39 (23%) had hypopigmentation. Patches were more often delineated at the ventral midline (32/39) than on the dorsal midline (7/39). The distribution of lesions was as follows: areas of the torso were most often affected (77%) and when the face, neck, arms and legs were affected pigmentation usually extended onto the torso; six patients had SegPD localized to the face. Only three of the 39 patients had extracutaneous abnormalities - atrial septal defect, strabismus with retinal hypopigmentation and a bronchogenic cyst - but the relationship to SegPD was uncertain and none had neurological abnormalities. SegPD is a relatively common pigmentary anomaly and most affected individuals are otherwise healthy. We propose reviving the term 'segmental pigmentation disorder' coined by Metzker and colleagues to describe children with segmental and block-like hypo-/hyperpigmentation with midline demarcation.

Ocular Albinism and Hypopigmentation Defects in Slc24a5—I— Mice

As part of a high-throughput mutagenesis and phenotyping process designed to discover novel drug targets, we generated and characterized mice with a targeted mutation in Slc24a5, a gene encoding a putative cation exchanger. Upon macroscopic examination, Slc24a5-/- mice were viable, fertile, and indistinguishable by coat color from their heterozygous and wild-type litter mates. Ophthalmoscopic examination revealed diffuse retinal hypopigmentation, and a histologic examination of the eye confirmed the presence of moderate-to-marked hypopigmentation of the retinal pigmented epithelium (RPE), ciliary body, and iris pigment epithelium (IPE). Hypopigmentation was most severe in the anterior layer cells of the IPE, where melanosomes were smaller, paler, and more indistinct than those of the anterior stroma and posterior IPE. The pigment granules of the posterior IPE appeared to be nearly as dark as those in stromal melanocytes; however, both cell layers were thinner and paler than corresponding layers in wild-type mice. Ultrastructural analysis of the RPE, IPE, and ciliary body pigmented cells confirmed that mutation of Slc24a5 results in marked hypopigmentation of melanosomes in optic cup-derived pigmented neuroepithelium in the eyes. Milder reductions in melanosome size and pigmentation were noted in neural crest-derived melanocytes. The severe hypopigmentation of neuroepithelium-derived cells in the eyes resulted in a novel form of ocular albinism in Slc24a5-/- mice. Our findings suggest that SLC24A5 may be a candidate gene for some forms of ocular albinism and for the BEY1/EYCL2 locus previously associated with central brown eye color in humans.

Avaliação da perimetria macular em pacientes com degeneração macular relacionada à idade por meio do oftalmoscópio de rastreamento a laser

To evaluate the correlation between anatomical changes (hard druses, soft druses, hyperpigmentation, new vessels, detachment of retinal pigment epithelium, hypopigmentation and chorioretinal atrophy) and light sensitivity in patients with age-related macular degeneration (ARMD); analyze macular sensitivity in areas with no anatomical lesions in patients with ARMD and compared them to the control group in order to detect if there was any functional lesion in areas with no anatomical changes. A cross-sectional, comparative, descriptive and analytic study was performed. The case group consisted of 31 subjects with ARMD aged between 51 and 88 years. The control group consisted of 31 "healthy" subjects, without ARMD aged between 61 and 80 years. The groups were matched for gender and age. We performed static macular perimetry, red-red, using a scanning laser ophthalmoscope (SLO). Results of macular perimetry were correlated with the anatomic lesion identified in the same site by infrared laser and color photographs. Areas with new vessels or atrophy showed a significantly different sensitivity in relation to areas without anatomical lesions in patients with ARMD. There was significant functional loss in areas with no anatomical lesions in patients with ARMD in relation to the control group. Areas with new vessels or atrophy could be distinct factors for worsening of the localized macular sensitivity. There might be functional loss even in areas with no apparent anatomical changes in ARMD patients.