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To describe the neuroanatomical correlates of unilateral congenital isolated oculomotor palsy by means of high-resolution MRI.Children with a clinical diagnosis of congenital isolated oculomotr palsy and with a high-resolution MRI acquisition targeted on the orbits and cranial nerves were selected and included in the study. An experienced pediatric neuroradiologist evaluated all the exams, assessing the integrity and morphology of extraocular muscles, oculomotor, trochlear and abducens nerves as well as optic nerves and globes. Clinical data and ophthalmologic evaluations were also collected.Six children (age range: 1-16 years; males: 3) were selected. All patients showed, on the affected side (left:right = 5:1), anomalies of the III nerve and extraocular muscles innervated by the pathological nerve. One patient had complete nerve agenesis, two patients showed a diffuse thinning of the nerve, from the brainstem to the orbit and 3 patients showed a distal thinning of the oculomotor nerve, starting at the level of the cavernous sinus. In all cases atrophy of corresponding muscles was noticed, but the involvement of the affected muscles varied with the nervous pattern of injury.High-resolution MRI represents a valuable tool for the diagnosis of III nerve anomalies in unilateral congenital IOP, showing different patterns of nerve involvement and muscular atrophy.

Achromatopsia (ACHM) is a congenital cone photoreceptor disorder characterized by impaired color discrimination, low visual acuity, photosensitivity, and nystagmus. To date, six genes have been associated with ACHM (CNGA3, CNGB3, GNAT2, PDE6C, PDE6H, and ATF6), the majority of these being implicated in the cone phototransduction cascade. CNGA3 encodes the CNGA3 subunit of the cyclic nucleotide-gated ion channel in cone photoreceptors and is one of the major disease-associated genes for ACHM. Herein, we provide a comprehensive overview of the CNGA3 variant spectrum in a cohort of 1060 genetically confirmed ACHM patients, 385 (36.3%) of these carrying "likely disease-causing" variants in CNGA3. Compiling our own genetic data with those reported in the literature and in public databases, we further extend the CNGA3 variant spectrum to a total of 316 variants, 244 of which we interpreted as "likely disease-causing" according to ACMG/AMP criteria. We report 48 novel "likely disease-causing" variants, 24 of which are missense substitutions underlining the predominant role of this mutation class in the CNGA3 variant spectrum. In addition, we provide extensive in silico analyses and summarize reported functional data of previously analyzed missense, nonsense and splicing variants to further advance the pathogenicity assessment of the identified variants.

Item does not contain fulltext Cone dystrophy with supernormal rod response (CDSRR) is considered to be a very rare autosomal recessive retinal disorder. CDSRR is associated with mutations in KCNV2, a gene that encodes a modulatory subunit (Kv8.2) of a voltage-gated potassium channel. In this study, we found that KCNV2 mutations are present in a substantial fraction (2.2-4.3%) of a sample of 367 independent patients with a variety of initial clinical diagnoses of cone malfunction, indicating that CDSRR is underdiagnosed and more common than previously thought. In total, we identified 20 different KCNV2 mutations; 15 of them are novel. A new finding of this study is the substantial proportion of large deletions at the KCNV2 locus that accounts for 15.5% of the mutant alleles in our sample. We determined the breakpoints and size of all five different deletions, which ranged between 10.9 and 236.8 kb. Two deletions encompass the entire KCNV2 gene and one also includes the adjacent VLDLR gene. Furthermore, we investigated N-terminal amino acid substitution mutations for its effect on interaction with Kv2.1 using yeast two-hybrid technology. We found that these mutations dramatically reduce or abolish this interaction suggesting a lack of assembly of heteromeric Kv channels as one underlying pathomechanism of CDSRR. 32:1398-1406, 2011. (c)2011 Wiley Periodicals, Inc.

Alterazioni della motilita oculare in 128 soggetti con Cerebral Visual Impairment - Gli Autori hanno sottoposto ad accurato studio delle caratteristiche oculomotorie un campione di 128 soggetti con diagnosi di Cerebral Visual Impairment (CVI). E stato applicato un protocollo d’indagine che prevedeva l’analisi di otto parametri dell’oculomozione: lo scanning dell’ambiente, il mantenimento della fissazione, i movimenti saccadici intenzionali, i movimenti di inseguimento lento (smooth pursuit), le deviazioni parossistiche dello sguardo (paroxismal ocular deviations), lo strabismo e il nistagmo. I risultati sono interessanti e dimostrano come la motilita oculare sia pesantemente interessata nel CVI (94% dei casi). Questi danni sono specifici e non consistono semplicemente in uno strabismo o nel nistagmo, ma colpiscono il sistema oculomotorio in alcune delle sue funzioni basilari, come l’esecuzione di saccadi volontarie, l’inseguimento, l’esplorazione visiva. Riteniamo che tali alterazioni non consentano di sfruttare appieno le potenzialita visive e piu in generale percettive del soggetto e ostacolino l’uso del canale visivo nelle attivita cognitive. Parole chiave: CVI, strabismo, nistagmo, paralisi cerebrale infantile

Mutations in the brain-specific P/Q type Ca2+ channel α1 subunit gene, CACNA1A, have been identified in three clinically distinct disorders, spinocerebellar ataxia type 6 (SCA6), episodic ataxia type 2 (EA2), and familial hemiplegic migraine type 1 (FHM1). SCA6 is associated with small expansions of a CAG repeat at the 3′ end of the gene, while point mutations are mostly responsible for its two allelic disorders, FHMI and EA2. From the electrophysiological point of view, while FHMI mutations lead to a gain of function [Tottene A, Fellin T, Pagnutti S, Luvisetto S, Striessnig J, Fletcher C, et al. Familial hemiplegic migraine mutations increase Ca(2+) influx through single human CaV2.1 channels and decrease maximal CaV2.1 current density in neurons. Proc Natl Acad Sci 99 (20) (2002) 13284–13289.], EA2 mutations usually generate a loss of channel function [Guida S, Trettel F, Pagnutti S, Mantuano E, Tottene A, Veneziano L, et al. Complete loss of P/Q calcium channel activity caused by a CACNA1A missense mutation carried by patients with episodic ataxia type 2. Am J Hum Genet 68 (3) (2001) 759–764, Wappl E, Koschak A, Poteser M, Sinnegger MJ, Walter D, Eberhart A, et al. Functional consequences of P/Q-type Ca2+ channel Cav2.1 missense mutations associated with episodic ataxia type 2 and progressive ataxia. J Biol Chem 277 (9) (2002) 6960–6966.]. In the present study, we describe a child affected by permanent non-fluctuating limb and trunk ataxia with a quite early age of onset. Interestingly, the size of the CACNA1A triplet repeat region in the patient is within the normal range while he carries a novel de novo missense mutation in this gene, p.R1664Q. Although functional data are not available, based on the literature data indicating that severe reductions in P/Q-type channel activity favour episodic and/or progressive ataxic symptoms [Wappl E, Koschak A, Poteser M, Sinnegger MJ, Walter D, Eberhart A, et al. Functional consequences of P/Q-type Ca2+ channel Cav2.1 missense mutations associated with episodic ataxia type 2 and progressive ataxia. J Biol Chem 2002;277(9):6960–6966.], we hypothesize that the functional consequence of the mutation here identified is a partial loss of the Ca channel function. In conclusion, the clinical and molecular findings reported here suggest the opportunity to screen for point mutation in this gene, even patients with a clinical phenotype for some aspects slightly different from the typical picture more commonly associated to SCA6, EA2 or FHM1 diseases.

We recently showed that mutations in the CNGA3 gene encoding the alpha -subunit of the cone photoreceptor cGMP-gated channel cause autosomal recessive complete achromatopsia linked to chromosome 2q11. We now report the results of a first comprehensive screening for CNGA3 mutations in a cohort of 258 additional independent families with hereditary cone photoreceptor disorders. CNGA3 mutations were detected not only in patients with the complete form of achromatopsia but also in incomplete achromats with residual cone photoreceptor function and (rarely) in patients with evidence for severe progressive cone dystrophy. In total, mutations were identified in 53 independent families comprising 38 new CNGA3 mutations, in addition to the 8 mutations reported elsewhere. Apparently, both mutant alleles were identified in 47 families, including 16 families with presumed homozygous mutations and 31 families with two heterozygous mutations. Single heterozygous mutations were identified in six additional families. The majority of all known CNGA3 mutations (39/46) are amino acid substitutions compared with only four stop-codon mutations, two 1-bp insertions and one 3-bp in-frame deletion. The missense mutations mostly affect amino acids conserved among the members of the cyclic nucleotide gated (CNG) channel family and cluster at the cytoplasmic face of transmembrane domains (TM) S1 and S2, in TM S4, and in the cGMP-binding domain. Several mutations were identified recurrently (e.g., R277C, R283W, R436W, and F547L). These four mutations account for 41.8% of all detected mutant CNGA3 alleles. Haplotype analysis suggests that the R436W and F547L mutant alleles have multiple origins, whereas we found evidence that the R283W alleles, which are particularly frequent among patients from Scandinavia and northern Italy, have a common origin.

Purpose: To present a checklist for the evaluation of low vision in uncooperative patients; in this specific case, children with neuroEogicai deficits. Method: The checklist includes several behavioral indicators obtainable with a standard clinical examination. Each test is assigned a score (0=failure, ]=success). The final visual quotient score is obtained by dividing the partial score by the total number of tests performed. Eleven children with cerebral visual impairment were studied using behavioral and preferential looking techniques. Results: Visual quotient was >0 in all patients, indicating that residual visual function was always detectable. Average visual quotient was 0.74. Conclusion: Visual quotient can be useful both for follow-up examinations and comparison and integration with other evaluation methods (behavioral and instrumental) of residual visual capacity. In particular, if combined with preferential looking techniques, visual quotient testing permits characterization of the entire spectrum of low vision. Journal of Pediatrie Ophthalmology and Strabismus 20(?;38:90-94.

Bardet-Biedl syndrome (BBS) is ahereditary autosomal-recessive disorder,characterized by mental retardation, obesity,pigmentary retinopathy,polydactyly and, only in males, hypogenitalism.Even though genetic studies haverevealed five different forms of BBS correlatedto distinct loci on differentchromosomes, a diagnosis of BBS is stillprimarily based on clinical data. Thepresent study discusses the evolutionof clinical ophthalmological andelectrophysiological characteristics ofBBS patients in developmental age.

Duane's retraction syndrome is sometimes associated with developmental ocular and extraocular abnormalities. This disorder may also be present in association with specific malformative syndromes. The authors report the clinical features of a seven-year-old female affected by Duane's retraction syndrome (D.R.S.), rectoperineal fistula, imperforate anus and other congenital malformations. From two extensive reviews of 106 reports published before 1982 and from a search (using Medline 1981–1994) for reports of congenital malformations associated with this syndrome, no cases of sporadic D.R.S. associated with the perineal malformations mentioned were found, even though imperforate anus is considered the commoner of hindgut malformation.

To obtain quantitative data on the optic disc excavation in children affected by cerebral visual impairment (CVI) by using the Heidelberg Retinal Tomograph (HRT)-II (Heidelberg Engineering, Heidelberg, Germany).A total of 24 subjects affected by CVI (mean age, 7.28 years) were examined: 16 in alert conditions and 8 under general anesthesia. The following parameters of the optic nerve head were examined: disc area, cup area, rim area, cup volume, rim volume, cup-to-disc area ratio, mean cup depth, maximum cup depth, cup shape measure, and mean retinal nerve fiber layer (RNFL) thickness. The tomographic results in children with CVI were compared with those of 88 normal, alert subjects of similar age.The optic disc of patients with CVI appeared smaller than normal. Its excavation, however, was more pronounced. Several tomographic parameters were altered in CVI-affected subjects. Statistical analysis showed a highly significant probability in cup-to-disc area ratio (P0.01, both eyes), rim area (P0.01, both eyes), cup shape measure (P0.01, right eye; P0.01, left eye), and mean RNFL thickness (P0.01, right eye; P0.01, left eye). A novel observation was temporal atrophy of the optic nerve head in CVI.The data provide a tridimensional, objective evaluation of the anatomic alterations of the optic nerve head in children with CVI. Furthermore, tomographic standards for optic disc shape in normal children are set for the first time.

Contains fulltext : 47591.pdf (Publisher’s version ) (Closed access) Achromatopsia is a congenital, autosomal recessively inherited disorder characterized by a lack of color discrimination, low visual acuity (

Two infants who presented with wide-amplitude and high-frequency nystagmus and lack of visual awareness in the first 3 months of life were studied. No ocular abnormalities were found. Neurodevelopmental examination, visual evoked potentials and electroretinograms were normal. One infant underwent MRI which resulted in normal findings. Two months later both patients showed increased visual responsiveness and a gradual reduction of the nystagmus amplitude. By 5 months of age nystagmus was no longer detectable and both infants appeared to be visually, developmentally, and neurologically normal. Follow-up at 3 years of age for subject 1 and at 11 months for subject 2 showed that both the infants maintained the normal ophthalmological and neurological assessments. We diagnosed delayed visual maturation with oculomotor involvement.