title: Congenital cranial dysinnervation disorders.
abstract: The European Neuromuscular Centre (ENMC) derived the term Congenital Cranial Dysinnervation Disorders in 2002 at an international workshop for a group of congenital neuromuscular diseases. CCDDs are congenital, non-progressive ophthalmoplegia with restriction of globe movement in one or more fields of gaze. This group of sporadic and familial strabismus syndromes was initially referred to as the 'congenital fibrosis syndromes' because it was assumed that the primary pathologic process starts in the muscles of eye motility. Over the last few decades, evidence has accumulated to support that the primary pathologic process of these disorders is neuropathic rather than myopathic. This is believed that for normal development of extra ocular muscles and for preservation of muscle fiber anatomy, normal intra-uterine development of the innervation to these muscles is essential. Congenital dysinnervation to these EOMs can lead to abnormal muscle structure depending upon the stage and the extent of such innervational defects. Over last few years new genes responsible for CCDD have been identified, permitting a better understanding of associated phenotypes, which can further lead to better classification of these disorders. Introduction of high-resolution MRI has led to detailed study of cranial nerves courses and muscles supplied by them. Thus, due to better understanding of pathophysiology and genetics of CCDDs, various treatment modalities can be developed to ensure good ocular alignment and better quality of life for patients suffering from the same.
authors.affiliation: Department of Ophthalmology, All India Institute of Medical Sciences, Rishikesh, India. dr.anupamsingh@gmail.com.|Ophthalmology Department, All India Institute of Medical Sciences, Rishikesh, 249203, Uttarakhand, India. dr.anupamsingh@gmail.com.
authors.forename: Anupam
authors.initials: A
authors.lastname: Singh
authors.affiliation: Department of Ophthalmology, Guru Nanak Eye Centre, Maulana Azad Medical College, New Delhi, India.
authors.forename: P K
authors.initials: PK
authors.lastname: Pandey
authors.affiliation: Department of Ophthalmology, All India Institute of Medical Sciences, Rishikesh, India.
authors.forename: Ajai
authors.initials: A
authors.lastname: Agrawal
authors.affiliation: Department of Ophthalmology, All India Institute of Medical Sciences, Rishikesh, India.
authors.forename: Sanjeev Kumar
authors.initials: SK
authors.lastname: Mittal
authors.affiliation: Department of Ophthalmology, All India Institute of Medical Sciences, Rishikesh, India.
authors.forename: Kartik Maheshbhai
authors.initials: KM
authors.lastname: Rana
authors.affiliation: Department of Ophthalmology, All India Institute of Medical Sciences, Rishikesh, India.
authors.forename: Chirag
authors.initials: C
authors.lastname: Bahuguna
mesh_terms: D003391:Cranial Nerves / Q000002:abnormalities*; D020022:Genetic Predisposition to Disease; D006801:Humans; D015835:Ocular Motility Disorders / Q000151:congenital* / Q000235:genetics; D009801:Oculomotor Muscles / Q000294:innervation*
keywords: Congenital cranial dysinnervation disorders; Congenital fibrosis of extra ocular muscles; Möbius syndrome; Strabismus