IC3D Classification of Corneal Dystrophies-Edition 3.

PURPOSE: The International Committee for the Classification of Corneal Dystrophies (IC3D) was created in 2005 to develop a new classification system integrating current information on phenotype, histopathology, and genetic analysis. This update is the third edition of the IC3D nomenclature. METHODS: Peer-reviewed publications from 2014 to 2023 were evaluated. The new information was used to update the anatomic classification and each of the 22 standardized templates including the level of evidence for being a corneal dystrophy [from category 1 (most evidence) to category 4 (least evidence)]. RESULTS: Epithelial recurrent erosion dystrophies now include epithelial recurrent erosion dystrophy, category 1 ( COL17A1 mutations, chromosome 10). Signs and symptoms are similar to Franceschetti corneal dystrophy, dystrophia Smolandiensis, and dystrophia Helsinglandica, category 4. Lisch epithelial corneal dystrophy, previously reported as X-linked, has been discovered to be autosomal dominant ( MCOLN1 mutations, chromosome 19). Classic lattice corneal dystrophy (LCD) results from TGFBI R124C mutation. The LCD variant group has over 80 dystrophies with non-R124C TGFBI mutations, amyloid deposition, and often similar phenotypes to classic LCD. We propose a new nomenclature for specific LCD pathogenic variants by appending the mutation using 1-letter amino acid abbreviations to LCD. Pre-Descemet corneal dystrophies include category 1, autosomal dominant, punctiform and polychromatic pre-Descemet corneal dystrophy (PPPCD) ( PRDX3 mutations, chromosome 10). Typically asymptomatic, it can be distinguished phenotypically from pre-Descemet corneal dystrophy, category 4. We include a corneal dystrophy management table. CONCLUSIONS: The IC3D third edition provides a current summary of corneal dystrophy information. The article is available online at https://corneasociety.org/publications/ic3d .

von Hippel-Lindau disease: Updated guideline for diagnosis and surveillance.

von Hippel Lindau disease (vHL) is caused by a hereditary predisposition to multiple neoplasms, especially hemangioblastomas in the retina and CNS, renal cell carcinomas (RCC), pheochromocytomas, neuroendocrine pancreatic tumours (PNET) and endolymphatic sac tumours. Evidence based approaches are needed to ensure an optimal clinical care, while minimizing the burden for the patients and their families. This guideline is based on evidence from the international vHL literature and extensive research of geno- and phenotypic characteristics, disease progression and surveillance effect in the national Danish vHL cohort. We included the views and preferences of the Danish vHL patients, ensured consensus among Danish experts and compared with international recommendations. RECOMMENDATIONS: vHL can be diagnosed on clinical criteria, only; however, in most cases the diagnosis can be supported by identification of a pathogenic or likely pathogenic variant in VHL. Surveillance should be initiated in childhood in persons with, or at risk of, vHL, and include regular examination of the retina, CNS, inner ear, kidneys, neuroendocrine glands, and pancreas. Treatment of vHL manifestations should be planned to optimize the chance of cure, without unnecessary sequelae. Most manifestations are currently treated by surgery. However, belzutifan, that targets HIF-2α was recently approved by the U.S. Food and Drug Administration (FDA) for adult patients with vHL-associated RCC, CNS hemangioblastomas, or PNETs, not requiring immediate surgery. Diagnostics, surveillance, and treatment of vHL can be undertaken successfully by experts collaborating in multidisciplinary teams. Systematic registration, collaboration with patient organisations, and research are fundamental for the continuous improvement of clinical care and optimization of outcome with minimal patient inconvenience.

TUBB3 Arg262His causes a recognizable syndrome including CFEOM3, facial palsy, joint contractures, and early-onset peripheral neuropathy.

Microtubules are formed from heterodimers of alpha- and beta-tubulin, each of which has multiple isoforms encoded by separate genes. Pathogenic missense variants in multiple different tubulin isoforms cause brain malformations. Missense mutations in TUBB3, which encodes the neuron-specific beta-tubulin isotype, can cause congenital fibrosis of the extraocular muscles type 3 (CFEOM3) and/or malformations of cortical development, with distinct genotype-phenotype correlations. Here, we report fourteen individuals from thirteen unrelated families, each of whom harbors the identical NM_006086.4 (TUBB3):c.785G>A (p.Arg262His) variant resulting in a phenotype we refer to as the TUBB3 R262H syndrome. The affected individuals present at birth with ptosis, ophthalmoplegia, exotropia, facial weakness, facial dysmorphisms, and, in most cases, distal congenital joint contractures, and subsequently develop intellectual disabilities, gait disorders with proximal joint contractures, Kallmann syndrome (hypogonadotropic hypogonadism and anosmia), and a progressive peripheral neuropathy during the first decade of life. Subsets may also have vocal cord paralysis, auditory dysfunction, cyclic vomiting, and/or tachycardia at rest. All fourteen subjects share a recognizable set of brain malformations, including hypoplasia of the corpus callosum and anterior commissure, basal ganglia malformations, absent olfactory bulbs and sulci, and subtle cerebellar malformations. While similar, individuals with the TUBB3 R262H syndrome can be distinguished from individuals with the TUBB3 E410K syndrome by the presence of congenital and acquired joint contractures, an earlier onset peripheral neuropathy, impaired gait, and basal ganglia malformations.

[Diagnosis, monitoring and treatment of tuberous sclerosis complex].

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder with highly varying disease manifestations, many of which cause extensive morbidity. There are international consensus criteria for the diagnosis, monitoring and treatment of TSC, and approved medical treatment for some of the most serious disease manifestations. However, organisation of a rational and coordinated care of TSC patients involves many different medical specialities and is only sparsely described. This review describes the interdisciplinary care of TSC patients at Aarhus University Hospital, Denmark.

Retinal hemangioblastoma: prevalence, incidence and frequency of underlying von Hippel-Lindau disease.

BACKGROUND AND AIMS: We aimed to determine the frequency of von Hippel-Lindau disease (vHL) as the underlying cause of retinal hemangioblastoma and to estimate retinal hemangioblastoma incidence and prevalence in a national cohort study. METHODS: Through the national patient register and vHL research database, we identified 81 patients diagnosed with a retinal hemangioblastoma in Denmark between 1977 and 2014. Consent was obtained for 54 living and 10 deceased patients with retinal hemangioblastoma. For each participant, we collected medical records and family information. Almost all (63 of 64) participants were or had previously been tested for mutations in the VHL gene. RESULTS: Overall, 84% of the participants (54 of the 64) had vHL. Compared with the non-vHL patients, the vHL patients had their first retinal hemangioblastoma at a younger age (22.5 vs 40 years), and were more likely to have an asymptomatic first hemangioblastoma (80% vs 20%). Overall, 76% (41 of 54) of the vHL patients had a family history of vHL, while none of the patients without vHL did. Despite the rarity of the disease, on average more than eight new tumours are diagnosed each year due to multiple tumour development in vHL patients. The estimated prevalence of patients with retinal hemangioblastoma was up to 1 in 73 080 individuals. CONCLUSION: In the first national study in which almost all participants were genetically tested, vHL was the underlying cause of retinal hemangioblastoma in 84% of cases; more often than previously reported. We recommend that genetic and clinical vHL screening should be performed in all patients with retinal hemangioblastoma.

Is Tadpole Pupil in an Adolescent Girl Caused by Denervation Hypersensitivity?

Tadpole pupil is a rarely encountered phenomenon caused by episodic, segmental iris dilator muscle spasm of short duration (2-15 minutes), occurring in clusters without a known precipitating factor. It has most commonly been described in women aged 28 to 48 years. A few hypotheses on pathogenesis have been discussed but none has been proved. Here, we present an adolescent girl with bilateral tadpole pupil that appeared during physical exercise. This is the first pediatric case of tadpole pupil, not caused by preceding surgery, to be published. Based on (1) this case in which tadpole pupil developed when the norepinephrine level rose during exercise, (2) the high ratio of patients with tadpole pupil who concurrently have or later develop Horner syndrome, in which denervation hypersensitivity is well described, (3) a previous report of a patient with both tadpole pupil and Horner syndrome who had denervation hypersensitivity on pharmacological testing, (4) a 29-year-old man with unilateral tadpole pupil induced by exercise, and (5) a 19-year-old man with bilateral tadpole pupil and possible autonomic neuropathy, we suggest denervation hypersensitivity as a probable pathogenic mechanism causing tadpole pupil. In addition, a suggestion for investigations to be performed in future pediatric cases is provided.

IC3D classification of corneal dystrophies--edition 2.

PURPOSE: To update the 2008 International Classification of Corneal Dystrophies (IC3D) incorporating new clinical, histopathologic, and genetic information. METHODS: The IC3D reviewed worldwide peer-reviewed articles for new information on corneal dystrophies published between 2008 and 2014. Using this information, corneal dystrophy templates and anatomic classification were updated. New clinical, histopathologic, and confocal photographs were added. RESULTS: On the basis of revisiting the cellular origin of corneal dystrophy, a modified anatomic classification is proposed consisting of (1) epithelial and subepithelial dystrophies, (2) epithelial-stromal TGFBI dystrophies, (3) stromal dystrophies, and (4) endothelial dystrophies. Most of the dystrophy templates are updated. The entity "Epithelial recurrent erosion dystrophies" actually includes a number of potentially distinct epithelial dystrophies (Franceschetti corneal dystrophy, Dystrophia Smolandiensis, and Dystrophia Helsinglandica) but must be differentiated from dystrophies such as TGFBI-induced dystrophies, which are also often associated with recurrent epithelial erosions. The chromosome locus of Thiel-Behnke corneal dystrophy is only located on 5q31. The entity previously designated as a variant of Thiel-Behnke corneal dystrophy on chromosome 10q24 may represent a novel corneal dystrophy. Congenital hereditary endothelial dystrophy (CHED, formerly CHED2) is most likely only an autosomal recessive disorder. The so-called autosomal dominant inherited CHED (formerly CHED1) is insufficiently distinct to continue to be considered a unique corneal dystrophy. On review of almost all of the published cases, the description appeared most similar to a type of posterior polymorphous corneal dystrophy linked to the same chromosome 20 locus (PPCD1). Confocal microscopy also has emerged as a helpful tool to reveal in vivo features of several corneal dystrophies that previously required histopathologic examination to definitively diagnose. CONCLUSIONS: This revision of the IC3D classification includes an updated anatomic classification of corneal dystrophies more accurately classifying TGFBI dystrophies that affect multiple layers rather than are confined to one corneal layer. Typical histopathologic and confocal images have been added to the corneal dystrophy templates.

Von Hippel-Lindau disease (vHL). National clinical guideline for diagnosis and surveillance in Denmark. 3rd edition.

These clinical guidelines outline the criteria and recommendations for diagnostic and genetic work-up of families suspected of von Hippel-Lindau disease (vHL), as well as recommendations for prophylactic surveillance for vHL patients. The guideline has been composed by the Danish Coordination Group for vHL which is comprised of Danish doctors and specialists interested in vHL. The recommendations are based on longstanding clinical experience, Danish original research, and extensive review of the international literature. vHL is a hereditary multi-tumour disease caused by germline mutations in the VHL gene. vHL is inherited in an autosomal dominant manner. Predisposed individuals are advised to undergo prophylactic examinations, as they are at lifelong risk of developing multiple cysts and tumours, especially in the cerebellum, the spinal cord, the retina (hemangioblastomas), the kidneys (renal cell carcinoma), the adrenal glands (pheochromocytoma), the pancreas, as well as in other organs. As many different organs can be affected, several medical specialities often take part in both diagnosis and treatment of manifestations. vHL should be suspected in individuals with a family history of the disease, and/or in individuals with a vHL-associated manifestation; i.e. a hemangioblastoma in the retina or the central nervous system, familial or bilateral pheochromocytomas, familial, multiple, or early onset renal cell carcinomas, and in individuals with an endolymphatic sac tumour in the inner ear. Individuals suspected of vHL should be referred to a department of clinical genetics for genetic work-up and counselling as well as have a clinical work-up to identify any undiagnosed vHL-associated manifestations. This guideline describes the elements of the clinical diagnostic work-up, as well as the genetic work-up, counselling, and mutation screening. Individuals who are affected with vHL, individuals at risk of vHL, and VHL-mutation carriers are advised to follow the surveillance program which consists of regular prophylactic examinations relevant to different age groups. The examinations are recommended to start in infancy with annual paediatric examinations and ophthalmoscopy until the age of five years. From five to 14 years, annual plasma-metanephrine and plasma-normetanephrine tests, as well as annual hearing examinations are added. Also, an MRI (Magnetic Resonance Imaging) examination of the CNS and abdomen should be done between the ages of eight and 14 years. After the age of 15 years, individuals should be referred to: a) annual ophthalmoscopy in dilation, b) annual neurological examination, c) every two years: MRIs of the CNS, including the inner ear, d) annual ultrasound/MRI of the abdomen, e) annual plasma-metanephrine, plasma-normetanephrine, and plasma-chromogranin A tests, and f) annual hearing examination at a department of audiology. It is advised that one doctor takes on the responsibility of coordination of and referral to the many examinations, and the communication with the patient. To facilitate the coordination, and especially for the patients' own use, a mobile chart can be used. In 2012, the Danish vHL Coordination Group established a national vHL database comprising individuals with vHL and their relatives, as well as individuals examined for vHL. The database is designated to be a treatment and diagnostic instrument, as well as a tool in future vHL research in Denmark.

[Idiopathic intracranial hypertension is a rare cause of headache in children]. / Idiopatisk intrakraniel hypertension er en sjælden årsag til hovedpine hos børn.

Idiopathic intracranial hypertension is often believed to be an illness exclusively occurring in obese women in their twenties and thirties. This case describes a four-year-old boy presenting with headache, vomiting photophobia and double vision for six days. He did not have a fever; and all exams and tests, including a magnetic resonance imaging of the brain showed normal values. During the eye examination, he was found to have bilateral papilloedema and when undergoing lumbar puncture an elevated pressure of 230 mm H(2)O was discovered. The patient was diagnosed with idiopathic intracranial hypertension and treated with azetazolamide. Within few days, his symptoms disappeared.

Eye features in three Danish patients with multisystemic smooth muscle dysfunction syndrome.

BACKGROUND: A de novo mutation of the ACTA2 gene encoding the smooth muscle cell α-actin has been established in patients with multisystemic smooth muscle dysfunction syndrome associated with patent ductus arteriosus and mydriasis present at birth. OBJECTIVE: To describe the structural ocular findings in three Danish children with this new syndrome and evaluate the possible functional consequences for visual development of the poorer imaging condition. RESULTS: Unresponsive mydriatic pupils with scalloping wisps of persistent pupillary membrane from the iris collarette were an early indicator of this rare genetic disorder in all three cases. Tortuousity of retinal arterioles was the main posterior pole finding, apparent during the first year of life and with a tendency to increase with age. In one case, it progressed to an aneurysmal-like state with breakdown of the blood-retinal barrier. CONCLUSIONS: Congenital mydriasis is an extremely rare pupil anomaly and is the feature for the early diagnosis of this new syndrome. The ophthalmologist should act in close collaboration with other specialists owing to the risk of aortic and cerebrovascular diseases and other complications associated with this disorder.

von Hippel-Lindau disease: surveillance strategy for endolymphatic sac tumors.

PURPOSE: : Up to 16% of patients with the hereditary von Hippel-Lindau disease develop endolymphatic sac tumors of the inner ear. Early diagnosis and treatment of endolymphatic sac tumors can prevent audiovestibular morbidity, but optimal endolymphatic sac tumor surveillance strategy has yet to be determined. We aimed to evaluate endolymphatic sac tumor surveillance to determine the best surveillance strategy. METHODS: : In a national prospective study, 40 VHL mutation carriers were interviewed about audiovestibular symptoms and had audiological examinations and magnetic resonance imaging of the inner ear. Further, we performed a meta-analysis including all reported endolymphatic sac tumor von Hippel-Lindau disease cases in the literature (N = 140 with 156 endolymphatic sac tumors). RESULTS: : In the prospective study, endolymphatic sac tumors were suspected based on audiovestibular symptoms, audiometry, and magnetic resonance imaging in 34%, 30%, and 12.5% of subjects, respectively. In total, more than 90% of radiologically diagnosed endolymphatic sac tumors were associated with abnormal audiometric findings. No endolymphatic sac tumor genotype-phenotype correlations were found. CONCLUSION: : We recommend annual audiometry as a first-line endolymphatic sac tumor screening tool, and in countries where periodic surveillance magnetic resonance imaging of the central nervous system is performed, specific images of the inner ear should be included. Audiometric abnormalities in patients with von Hippel-Lindau disease without magnetic resonance imaging-visible endolymphatic sac tumors could be due to microscopic endolymphatic sac tumors. Determination of audiometric endolymphatic sac tumor characteristics could further target screening and improve endolymphatic sac tumor diagnosis.

Interstitial deletion of the short arm of chromosome 1 (1p13.1p21.1) in a girl with mental retardation, short stature and colobomata.

Interstitial deletions on the short arm of chromosome 1 are rare. We describe a girl with severe mental retardation, short stature and dysmorphic features including colobomata where high-resolution comparative genomic hybridization revealed an interstitial deletion with breakpoints in band 1p13.1 and 1p21.1. The deletion was further characterized by real-time polymerase chain reaction. We hypothesize that haploinsufficiency of WNT2B (wingless-type MMTV integration site family, member 2B) and NTNG1 (Netrin G1) contributed to the patient's phenotype.