(What's the story) morning glory? MRI findings in morning glory disc anomaly.

PURPOSE: Morning glory disc anomaly (MGDA) is a rare congenital ophthalmologic disorder. Historically it has been diagnosed fundoscopically, with little in the literature regarding its imaging findings. The purpose of this study is to further characterize the orbital and associated intracranial magnetic resonance imaging (MRI) findings of MGDA in our tertiary pediatric center. METHODS: A retrospective review was performed of fundoscopically-diagnosed cases of MGDA, that had been referred for MRI. All MRI studies were scrutinized for orbital and other intracranial abnormalities known to occur in association with MGDA. RESULTS: 18 of 19 cases of MGDA showed three characteristic MRI findings: funnel-shaped morphology of the posterior optic disc, abnormal soft tissue associated with the retrobulbar optic nerve, and effacement of adjacent subarachnoid spaces. The ipsilateral (intraorbital) optic nerve was larger in one patient and smaller in six. The ipsilateral optic chiasm was larger in two patients and smaller in one. CONCLUSION: This study represents a comprehensive radiological-led investigation into MGDA. It describes the most frequently-encountered MRI findings in MGDA and emphasizes the importance of MRI in this cohort, i.e., in distinguishing MGDA from other posterior globe abnormalities, in assessing the visual pathway, and in screening for associated intracranial abnormalities - skull base/cerebral, vascular, and facial. It hypothesizes neurocristopathy as an underlying cause of MGDA and its associations. Caliber abnormalities of the ipsilateral optic nerve and chiasm are a frequent finding in MGDA. Optic pathway enlargement should not be labeled "glioma". (239/250).

Bilateral Peters' anomaly, aniridia and Wilms tumour (WAGR syndrome) in monozygotic twins.

AIM: This study reports the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins subsequently diagnosed with Wilms tumour (WAGR syndrome). METHODS: Two monozygotic female twins were referred at age 2 months with bilateral corneal opacity. A diagnosis of Peters' anomaly associated to aniridia was made in both eyes of both twins. Physical examination and ultrasonography were carried out at 12 months of age to explore the possibility of WAGR-related anomalies, specifically Wilms tumour. DNA were isolated and subjected to whole exome sequencing. RESULTS: Peters' anomaly associated to aniridia in both eyes as well as bilateral Wilms tumour in both children were diagnosed. Exome analyses showed a large heterozygous deletion encompassing 6 648 473 bp in chromosome 11p13, using Integrative Genomics Viewer and AnnotSV software. CONCLUSION: WAGR syndrome is a rare contiguous gene deletion syndrome with a greater risk of developing Wilms tumour associated with Peters' anomaly and congenital aniridia. However, co-occurrence of both anomalies was rarely reported in twins, and never in both eyes of monozygotic twins. Here, we report the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins with WAGR syndrome.

Deep neurological phenotyping in oculo-dento-digital syndrome.

OBJECTIVES: Oculodentodigital dysplasia (ODDD) is a rare autosomal dominant congenital malformation syndrome characterized by high penetrance and great phenotypic heterogeneity. Neurological manifestations are thought to occur in about one third of cases, but systematic studies are not available. We performed deep neurological phenotyping of 10 patients in one ODDD pedigree. METHODS: Retrospective case series. We analyzed in depth the neurological phenotype of a three-generation family segregating the heterozygous c.416 T > C, p.(Ile139Thr) in GJA1. Clinical and neuroradiological features were retrospectively evaluated. Brain MRI and visual evoked potentials were performed in 8 and 6 cases, respectively. RESULTS: Central nervous system manifestations occurred in 5 patients, the most common being isolated ataxia either in isolation or combined with spasticity. Furthermore, sphincteric disturbances (neurogenic bladder and fecal incontinence) were recognized as the first manifestation in most of the patients. Subclinical electrophysiological alteration of the optic pathway occurred in all the examined patients. Neuroimaging was significant for supratentorial hypomyelination pattern and hyperintense superior cerebellar peduncle in all examined patients. CONCLUSION: The neurological involvement in ODDD carriers is often missed but peculiar clinical and radiological patterns can be recognized. Deep neurological phenotyping is needed to help untangle ODDD syndrome complexity and find genotype-phenotype correlations.

Hydrocephalus associated with a molar tooth sign: A distinct subtype of Joubert syndrome.

Hydrocephalus is rarely described in Joubert-Boltshauser syndrome (JBTS). The aim of this study was to investigate whether this association is a chance occurrence or potentially signifies a new phenotypic subtype. The databases of Wolfson Medical Center, Sourasky Medical Center, and EB's personal collection were reviewed. Records from an additional family were obtained from RG. The patients' medical records, prenatal ultrasounds, and magnetic resonance imaging were assessed. In addition, we reviewed the medical literature for the association of ventriculomegaly/hydrocephalus (VM/HC) in JBTS. Only seven cases (from five families) were found with prenatal onset of VM/HC, diagnosed during the second trimester; three pregnancies were terminated, one was stillborn and three were born, of which one died within a week, and another died at the age of 6 years. Additional central nervous system findings included dysgenesis of the corpus callosum, delayed sulcation, polymicrogyria, and pachygyria. We found 16 publications describing 54 patients with JBTS and VM/HC: only five were diagnosed at birth and three were diagnosed prenatally. Hydrocephalus is extremely rare in JBTS. The recurrence of this association, reported in several publications in multiple family members, suggests that it might represent a new phenotypic subtype of JBTS possibly associated with specific genes or variants. Further genetic studies are needed to confirm this hypothesis. WHAT THIS PAPER ADDS: The association of fetal hydrocephalus with Joubert-Boltshauser syndrome (JBTS) is very rare but not a chance association. This association represents a new phenotypic subtype of JBTS possibly linked to specific genes or variants.

OCT-angiography in optic disk pit after inverted ILM flap: A case report.

BACKGROUND: To describe OCT-angiography features in a case of an optic disk pit (ODP) which underwent a pars plana vitrectomy with inverted ILM flap for macular detachment. CASE PRESENTATION: A 12 years old child with an ODP responsible for a macular detachment underwent 23G vitrectomy in the subacute phase of the disease with an inverted ILM flap used as a plug over the lateral dehiscence of the pit. Among the various retinal imaging examinations performed in the post-operative period, the OCT-angiography showed very interesting features characterized by a capillary drop-out in correspondence of the superficial and deep capillary plexus, a fine texture of the choroid capillary layer and star-shaped folds in correspondence of both the outer retina and the choroid capillary layer. OCT-A performed 24 months after surgery showed a normalization of the macular perfusion which correlated with a full recovery of the visual acuity of the young child. CONCLUSIONS: OCT-A is an useful tool to monitor the subretinal fluid reabsorption after ILM inverted flap surgery for ODP-maculopathy and correlates with visual function. OCT-A may be useful in the follow-up of this rare condition as well as its response to therapeutic strategies.

Novel variant CPLANE 1: c.5051C>A (p.Ser1684Ter) in an Indian neonate with Joubert syndrome.

Joubert syndrome (JS) is a rare ciliopathy that presents with the triad of hypotonia, developmental delay and molar tooth sign (MTS) in brain MRI. Next-generation sequencing has identified about 35 genes which are known to cause JS of which CPLANE 1 mutation is found in 8%-10% of cases. We report a case of JS in an Indian neonate who presented with hypotonia, dysmorphic facies, polydactyly, syndactyly and occipital encephalocele. MRI of the brain revealed MTS, and compound heterozygous mutations in CPLANE 1 gene were detected by clinical exome sequencing, one of them a novel variant CPLANE 1: c.5051C>A (p.Ser1684Ter) in exon 26, which was inherited from the parents.

Surgical repair of interrupted right-sided cervical aortic arch with hypoplasia of the descending thoracic aorta in a child with PHACE syndrome.

Obstruction of a right cervical aortic arch in association with hypoplasia of the descending aorta is a rare congenital cardiac malformation. We report the case of a 6-month-old boy with posterior fossa anomalies, hemangioma, arterial anomalies, cardiac anomalies and eye anomalies (PHACE) syndrome and interruption of a right-sided cervical aortic arch. The descending thoracic aorta in the child had a long hypoplastic segment and the patient also had small ventricular septal defect and pulmonary valve stenosis. The surgical technique of reconstruction of the aortic arch and the descending thoracic aorta through a median sternotomy is described.

Two Siblings Showing a Mild Phenotype of Joubert Syndrome with a Specific CEP290 Variant.

Joubert syndrome (JS) is a genetic neurodevelopmental disorder characterized by lower brainstem dysplasia and cerebellar vermis agenesis termed molar tooth sign (MTS), psychomotor retardation, abnormal respiratory pattern in infancy, and oculomotor abnormalities. Arima syndrome (AS), which is a severe form of JS, is characterized by severe psychomotor retardation, congenital visual impairment, progressive renal dysfunction, and lower brainstem dysplasia from early infancy. Numerous patients with AS expire in early childhood. Recently, c.6012-12T> A in the CEP290 gene was reported as a specific variant of AS. Herein, we report the cases of two siblings showing a phenotype of JS with compound heterozygous mutations (c.6012-12T > A / c.5924delT) in the CEP290 gene. The older sister (aged 19 years) had hypotonia, hypertelorism, and anteverted nares since birth. As a neonate, she developed a transient abnormal respiratory pattern and nystagmus, and brain magnetic resonance imaging (MRI) showed MTS. The younger sister (aged 13 years) exhibited mild hypotonia and pendular nystagmus as a neonate; MRI revealed MTS. Both sisters had psychomotor retardation, oculomotor dysfunction, and bilateral renal cysts with normal renal function. They can walk and have simple conversation. They do not meet the diagnostic criteria for AS, and their symptoms were milder than those of previously reported cases with this specific mutation. This report indicates the expanding spectrum of the CEP290 variant.

Get Your Molar Tooth Right: Joubert Syndrome Misdiagnosis Unmasked by Whole-Exome Sequencing.

Joubert syndrome (JS) is a recessively inherited ciliopathy, characterized by a specific cerebellar and brainstem malformation recognizable on brain imaging as the "molar tooth sign" (MTS). Clinical signs include hypotonia, developmental delay, breathing abnormalities, and ocular motor apraxia. Older patients develop ataxia, intellectual impairment, and variable organ involvement. JS is genetically heterogeneous, with over 40 ciliary genes overall accounting for 65-75% cases. Thus, in recent years, the genetic diagnosis of JS has been based on the analysis of next-generation sequencing targeted gene panels. Since clinical features are unspecific and undistinguishable from other neurodevelopmental syndromes, the recognition of the MTS is crucial to address the patient to the appropriate genetic testing. However, the MTS is not always properly diagnosed, resulting either in false negative diagnoses (patients with the MTS not addressed to JS genetic testing) or in false positive diagnoses (patients with a different brain malformation wrongly addressed to JS genetic testing). Here, we present six cases referred for JS genetic testing based on inappropriate recognition of MTS. While the analysis of JS-related genes was negative, whole-exome sequencing (WES) disclosed pathogenic variants in other genes causative of distinct brain malformative conditions with partial clinical and neuroradiological overlap with JS. Reassessment of brain MRIs from five patients by a panel of expert pediatric neuroradiologists blinded to the genetic diagnosis excluded the MTS in all cases but one, which raised conflicting interpretations. This study highlights that the diagnostic yield of NGS-based targeted panels is strictly related to the accuracy of the diagnostic referral based on clinical and imaging assessment and that WES has an advantage over targeted panel analysis when the diagnostic suspicion is not straightforward.

Case Report: Identification of likely recurrent CEP290 mutation in a child with Joubert syndrome and cerebello-retinal-renal features.

Background. Joubert syndrome (JS) is a rare autosomal recessive ciliopathy with an estimated prevalence of 1 in 100,000. JS is characterized by hyperpnoea, hypotonia, ataxia, developmental delay and various neuropathological abnormalities in the brain including cerebellar hypoplasia and cerebellar vermis aplasia. JS can also have variable multi-organ involvement, including the retina, kidneys, liver, and musculoskeletal system. Methods and Results. Here we report a clinical description of two-year-old girl presenting with breathing difficulties, hyperechoic kidneys with loss of corticomedullary differentiation. Brain magnetic resonance imaging revealed the typical molar tooth sign consistent with a clinical diagnosis of JS and retinal examination showed severe retinal dystrophy leading to blindness. Molecular genetic analysis using whole exome sequencing and Sanger sequence confirmation demonstrated a homozygous mutation (c.5493delA, p.(A1832fs*19) in CEP290 which segregated from either parent and was consistent with the multisystem ciliopathy phenotype. This precise variant has been described previously in 2 families from the Kosovar-Albanian region suggesting this allele is a recurrent mutation in this population. Conclusions. Mutations in CEP290 lead to multisystem ciliopathy syndromes and molecular genetic diagnostics of such cases allows precise diagnosis, screening of at risk relatives and appropriate management.

Fetal neuroimaging findings in PHACE syndrome: case report and review of the literature.

OBJECTIVE: To describe the main prenatal sonographic and magnetic resonance imaging (MRI) features leading to the diagnosis of Posterior fossa malformations, Hemangiomas of the face, Arterial anomalies, Coarctation of the aorta and cardiac defects, and Eye abnormalities (PHACE) syndrome. The literature was also reviewed in order to determine the main neuroimaging features of fetuses with this condition. RESULTS: The index case was referred at 24 weeks' gestation with the probable diagnosis of Dandy-Walker malformation. Prenatal sonographic examination revealed hypoplasia of the left cerebellar hemisphere, hypoplasia of the cerebellar vermis, and enlarged cisterna magna (the "tilted telephone receiver sign"). Fetal MRI at 30 weeks confirmed the findings and also revealed an ipsilateral retrocerebellar cyst communicating with the asymmetrical dilated fourth ventricle, upward displacement of the left cerebellar hemisphere, and elevation of the ipsilateral tentorium. Postnatally, a large left facial segmental hemangioma as well as ipsilateral vascular intracranial malformations were identified, confirming the diagnosis of PHACE syndrome. A review of the literature revealed 11 reports describing 22 fetuses with prenatal imaging studies, including ours, confirming the high prevalence of specific posterior fossa abnormalities associated with PHACE syndrome. CONCLUSION: Our case and those reported in the literature support the observation that PHACE syndrome presents with characteristic features affecting the posterior fossa, which can be identified through prenatal sonography and fetal MRI.

Another Piece of the Puzzle of Anomalous Connectivity in Joubert's Syndrome.

We report on the conventional and diffusion tensor imaging (DTI) findings of a 2-year-old child with clinical presentation of Joubert's Syndrome (JS) and brainstem structural abnormalities as depicted by neuroimaging.Conventional magnetic resonance imaging (MRI) showed a "molar tooth" configuration of the brainstem. A band-like formation coursing in an apparent axial plane anterior to the interpeduncular fossa was noted and appeared to partially cover the interpeduncular fossa.DTI maps and three-dimensional (3D) tractography demonstrated a prominent red-encoded white matter bundle anterior to the midbrain. Probable aberrant course of the bilateral corticospinal tracts (CST) was also depicted. Absence of the decussation of the superior cerebellar peduncles and elongated thickened, horizontal superior cerebellar peduncle (SCP) reflecting the molar tooth sign were also shown.Our report and the review of the published cases suggest that DTI and tractography may be very helpful to differentiate between interpeduncular heterotopias and similarly located white matter bundles corroborating the underlying etiology of axonal guidance disorders in the complex group of ciliopathies including JS. Our case represents an important additional puzzle piece to explore the variability of these ciliopathies.

From the inside out: oculocerebrocutaneous syndrome without dermatological manifestations.

Delleman-Oorthuys or oculocerebrocutaneous syndrome (OCCS) is an extremely rare condition which relies on three pillars of manifestations: ophthalmological, neurological, and dermatological. It was first described by Delleman and Oorthuys in 1981, and since then, very few other cases have been reported. We report the case of a 13-month-old boy, referred to an ophthalmological tertiary service for investigation of a microglobe with a cystic retrobulbar mass on translucency test. MRI revealed a left microphthalmia, with extensive retrobulbar cystic lesions occupying the remaining orbit and protruding anteriorly the microglobe. Cerebral findings included polymicrogyria, subependymal nodular heterotopia at the level of the left occipital horn of the lateral ventricle, and an importantly enlarged mesencephalic tectum observed in association with an absent cerebellar vermis. The ensemble of malformations met the criteria for definite OCCS. Being a tremendously rare syndrome, OCCS will always represent a diagnostic challenge. However, its emblematic cutaneous manifestations might be an important part of the road map leading to its correct interpretation. Thus, when absent, diagnosis can be harder than usual, and, on these cases, neurologists, ophthalmologists, and radiologists play a crucial role.

Coexistence of Straatsma syndrome without macular extension and abnormal ellipsoid zone / Coexistência da síndrome de Straatsma sem extensão macular e zona elipsoide anormal

ABSTRACT Myelinated retinal nerve fibers are rare congenital anomalies that appear as gray-white patches. They may be present in a syndrome characterized by ipsilateral myelinated retinal nerve fibers, myopia and amblyopia. The author reported an ellipsoid zone defect on spectral domain optical coherence tomography in a case of Straatsma syndrome without macular extension.

RESUMO Fibras nervosas retinais mielinizadas são anomalias congênitas raras que aparecem como manchas branco-acinzentadas. Eles podem se apresentar em uma síndrome caracterizada por fibras nervosas retinais mielinizadas ipsilaterais, miopia e ambliopia. O autor relatou um defeito na zona elipsoide na tomografia de coerência óptica de domínio espectral em um caso de síndrome de Straatsma sem extensão macular.

Retinitis pigmentosa and molar tooth sign caused by novel AHI1 compound heterozygote pathogenic variants.

BACKGROUND: Joubert syndrome (JS) is a group of rare congenital disorders characterized by cerebellar vermis dysplasia, developmental delay, and retina dysfunctions. Herein, we reported a Chinese patient carrying a new variant in the AHI1 gene with mild JS, and the 3D structure of the affected Jouberin protein was also predicted. CASE PRESENTATION: The patient was a 31-year-old male, who presented difficulty at finding toys at the age of 2 years, night blindness from age of 5 years, intention tremor and walking imbalance from 29 years of age. Tubular visual field and retina pigmentation were observed on ophthalmology examinations, as well as molar tooth sign on brain magnetic resonance imaging (MRI). Whole exome sequence revealed two compound heterozygous variants at c.2105C>T (p.T702M) and c.1330A>T (p.I444F) in AHI1 gene. The latter one was a novel mutation. The 3D protein structure was predicted using I-TASSER and PyMOL, showing structural changes from functional ß-sheet and α-helix to non-functional D-loop, respectively. CONCLUSIONS: Mild JS due to novel variants at T702M and I444F in the AHI1 gene was reported. The 3D-structural changes in Jouberin protein might underlie the pathogenesis of JS.