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it occurs more often due to sporadic mutations in chromodomain helicase dna - binding protein ( chd7 ) but when inherited , the mutation is transferred in an autosomal dominant pattern .
charge stood for coloboma , heart disease , atresia choanae , retarded growth and retarded development , and/or central nervous system ( cns ) anomalies , genital hypoplasia , and ear anomalies / deafness . since the time it was first described by hall , the understanding of the phenotype expression of the charge syndrome has increased over the years .
recently , patients with charge syndrome have been reported to show basiocciput hypoplasia and basilar invagination . here
, we report a case of charge syndrome where there is involvement of symmetrical chorioretinal colobomata with craniovertebral junction anomalies and present a brief review of the literature .
a 27-year - old woman presented with complaints of poor vision in both eyes and inability to hear since birth .
27-year - old female with poor vision and inability to hear was subsequently diagnosed with charge syndrome .
( a and b ) standard photographs of the ears from lateral view show bilateral microtia grade
there was no iris coloboma but symmetrical , large colobomata involving the optic nerve , choroid , and retina were present [ figure 2a and b ] .
27-year - old female with poor vision and inability to hear was subsequently diagnosed with charge syndrome .
( a and b ) fundus photographs ( antero - posterior view ) show bilateral , symmetrical , chorioretinal colobomata involving the optic discs and macula ( arrows ) .
there was severe to profound sensorineural deafness on pure tone audiometry examination and brain stem evoked response audiometry with identifiable peak v on 125 db stimulus in both ears .
echocardiography revealed normal cardiac chamber dimensions and valve morphology with no residual shunt across pda closure .
x - ray kub ( kidney , urether , and bladder ) region and serum calcium were within normal limits .
magnetic resonance imaging ( mri ) revealed bilateral hypoplasia of vestibule , lateral semicircular canals , and cochlea with visualization of about 1-turns [ figure 3a and b ] .
vestibulo - cochlear nerves on both sides were of smaller size than the adjacent facial nerves with narrow internal acoustic meatus .
there was basilar invagination with short clivus , fused c2 and c3 vertebrae , and partially occipitalized atlas [ figure 3c ] .
there was a large posterior global defect with adjacent deformed and thinned out sclera around the optic disc in both eyes [ figure 3d ] .
chromosomal analysis revealed normal female karyotype ( 46 xx chromosomes ) in all the metaphases analyzed .
a diagnosis of charge syndrome was arrived at by satisfying three major criteria prelisted by blake et al . , namely , i ) coloboma ( retina and choroid ) , ii ) characteristic ear abnormalities , and iii ) cranial nerve dysfunction ( sensorineural deafness ) , plus three minor criteria , namely , i ) cardiovascular malformations , ii ) growth deficiency , and iii ) distinctive face .
the criteria for typical charge syndrome according to verloes are also met , namely , two major criteria of i ) coloboma ( choroid ) and ii ) hypoplastic semi - circular canals , plus three minor criteria of i ) rhombencephalic dysfunction ( sensorineural deafness ) , ii ) abnormal external ear , and iii ) malformation of mediastinal organs ( heart ) .
27-year - old female with poor vision and inability to hear was subsequently diagnosed with charge syndrome .
( a ) axial constructive interference in steady state ( ciss ) t2-weighted mri at the level of internal auditory meatus shows bilateral hypoplasia of semicircular canals seen as small saccular structures instead of normal  d  like canalicular structure ( small arrows ) and cochlea shows only one and half ( 11/2 ) turns instead of normal two and half ( 21/2 ) or more ( large arrows ) .
( b ) three - dimensional reconstruction of ciss mri images of the right internal auditory apparatus confirming rudimentary semicircular canals ( small arrow ) and hypoplasia of cochlea ( large arrow ) .
( c ) t2 fast spin echo mid - sagittal reconstruction of mri head shows associated craniovertebral junction anomaly with fused c2 and c3 vertebrae with rudimentary intervertebral disc ( dotted arrow ) and basilar invagination ( solid arrow ) .
( d ) axial ciss t2 weighted mri at the level of orbits shows defects of choroid ( solid arrows ) .
prophylactic laser retinopexy was done in both the eyes along the border of the coloboma to reduce the risk of future retinal detachments .
the features related to charge syndrome was first described by hall in 17 children with choanal atresia associated with multiple congenital anomalies [ mca ] and independently by hittner in 10 mca patients with coloboma , heart disease , and hearing loss .
charge to include the six cardinal features of coloboma , heart disease , atresia choanae , retarded growth and retarded development and/or cns anomalies , genital hypoplasia , and ear anomalies / deafness .
there has been a histopathological report of symmetrical involvement of ocular colobomata in a case report of charge syndrome .
the phenotype expression of charge syndrome has been updated over the years to include additional features and the criteria for diagnosis were further refined .
blake et al . , proposed a renewed definition of charge based on 11 criteria .
verloes updated the definition of charge further and proposed three new major and five minor signs .
the major (  the 3 c  ) signs included coloboma , atresia of choanae , and hypoplastic semi - circular canals .
evolving diagnostic criteria for charge syndrome ( adapted from pagon , blake , verloes , sanlaville ) the chd7 gene has been established as a genetic etiology for charge syndrome .
. other ocular anomalies are iris or eyelid coloboma , microphthalmia , microcornea , strabismus , nystagmus , optic nerve hypoplasia , persistent hyperplastic primary vitreous , anophthalmos , and anisometropia .
our case had large and symmetrical colobomata involving the optic disc , choroid , and retina .
unilateral or bilateral atresia of the choanae is an infrequently occurring developmental anomaly caused by membranous and/or bony obstruction of the posterior nasal choanae .
chestler et al . , did not find a single case of atresia choanae in their case series .
our case had bilateral and asymmetrical grade i / ii microtia and hypoplasia of semicircular canal and cochlea with severe to profound sensorineural hearing defect .
congenital heart defects like atrial septal defect , endocardial cushion defect , pda , and tetralogy of fallot are usually seen in charge syndrome .
basioccipital hypoplasia and basilar invagination have been reported in cases of charge syndrome by fujita et al .
the authors concluded that basioccipital hypoplasia and basilar invagination are prevalent in patients with charge syndrome , although they mentioned that their case series was biased . they had suggested these anomalies as possible new diagnostic criteria .
our case had basilar invagination with short clivus , fused cervical vertebrae , and occipitalized atlas .
from the case series of fujita et al . , and our case , it appears that craniovertebral junction anomalies may be an underdiagnosed association of charge syndrome .
therefore , if mri of basiocciput is done routinely in cases of charge syndrome , craniovertebral junction anomalies may be picked up more often . the diagnostic criteria for charge syndrome may require further revision to include craniovertebral anomalies
we have reported here a case of charge syndrome where there is involvement of symmetrical chorioretinal colobomata with craniovertebral junction anomalies .
its diagnostic criteria may require further revision with the addition of craniovertebral junction anomalies as one of the criteria .
we suggest mri of basiocciput along with internal auditory apparatus to be done routinely in cases of charge syndrome to rule out craniovertebral anomalies .
charge syndrome is a common cause of congenital anomalies . 
 its rate of incidence is about 1:10,000 . 
 it is phenotypically heterogeneous , usually a sporadic or autosomal dominant disorder resulting from a mutation in the chd7 ( chromodomain helicase dna - binding protein ) gene . since the time it was first described by hall,[1 ] the knowledge of the clinical characteristics of charge syndrome has increased over the years . 
 recently , basiocciput hypoplasia and basilar invagination in patients with charge syndrome have been reported . 
 we report here a case of charge syndrome where there is involvement of symmetrical chorioretinal colobomata with craniovertebral junction anomalies . 
 the patient had symmetrical chorioretinal colobomata , external and inner ear anomalies , sensorineural deafness , characteristic facial appearance , retarded growth and development , history of patent ductus arteriosus , and craniovertebral junction anomalies . 
 craniovertebral junction anomalies may be an under - diagnosed phenotypic expression of charge syndrome . 
 the diagnostic criteria of charge syndrome may require further revision to include the addition of craniovertebral junction anomalies .