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alagille syndrome is clinically defined by neonatal cholestatic jaundice with intrahepatic bile duct hypoplasia associated with additional findings , including a characteristic facies , peripheral pulmonary artery stenosis , butterfly - like vertebral anomalies , and ocular abnormalities .
ocular findings include posterior embryotoxon , iris abnormalities , optic disc anomalies , and fundus changes ( irregular pigmentation at the level of the retinal pigment epithelium , diffuse hypopigmentation , and punched out chorioretinal atrophy).1,2 to our knowledge , there are no cases in the literature presenting with alagille syndrome and chorioretinal atrophy involving the macula , as examined by optical coherence tomography ( oct ) and fundus autofluorescence .
herein , we report oct and fundus autofluorescence changes in a patient with this syndrome .
an 11-year - old girl with alagille syndrome was referred to the jichi medical university hospital before a liver biopsy during observation after liver transplantation .
liver transplantation was performed at the age of 20 months , and left pulmonary artery balloon dilation was performed at the age of 8 years .
she had an unusual triangular facies characterized by a broad overhanging forehead , deep - set hyperteloric eyes , and a small pointed chin .
best - corrected visual acuity in the right eye was 12/20 with 6.25 d 1.0d  90 , and in the left eye was 8/20 with 4.25 d 2.0 d  90. the patient was orthophoric and showed normal ocular movements . on slit lamp examination ,
funduscopy showed diffuse choroidal hypopigmentation with increased visibility of the choroidal blood vessels and symmetric well circumscribed macular discoloration ( figure 1 ) .
decreased retinal thickness was seen on oct ( rs-3000 , nidek , japan ) . on the basis of macular etdrs ( early treatment diabetic retinopathy study ) sectors , thickness of the center ( central fovea ) , inner ring ( 13 mm from the central fovea ) and outer ring ( 36 mm from the central fovea ) were 222 m , 254.8 m , and 241.0 m , respectively , in the right eye . in the left eye ,
in particular , the outer retinal ( nuclear ) layer and the photoreceptor inner segment / outer segment junctions were irregular and discontinuous , corresponding to macular discoloration ( figures 2 and 3 ) .
foveal architecture was preserved in both eyes with thinning . in high - magnification oct images ,
the border between the chorioretinal atrophy and the hypopigmented area of the macula was clearly defined .
the outer retinal thickness in the chorioretinal atrophic area was thinner than that in the hypopigmented area .
fundus autofluorescence imaging ( heidelberg retina angiograph 2 , heidelberg , germany ) showed hypofluorescent areas in the peripapillary regions extending along the macula corresponding to the chorioretinal atrophy .
these had an appearance similar to a sleep mask ( figure 4 ) . a mottled pattern of hyperautofluorescent areas was also detected in the macula .
visual field testing with goldmann perimetry only showed enlargement of the blind spots in both eyes .
serum vitamin a and vitamin e levels were 94 ( normal range 97316 ) iu / dl and 0.51 ( normal range 0.751.41 ) mg / dl , respectively .
in the largest series of patients with alagille syndrome , hingorani et al1 evaluated 22 patients with the condition . the most common ocular abnormalities in alagille syndrome were posterior embryotoxon ( 95% ) , iris abnormalities ( 45% ) , diffuse fundus hypopigmentation ( 57% ) , speckling of the retinal pigment epithelium ( 33% ) , and optic disc anomalies ( 76%).1 in studying retinal changes in alagille syndrome , hingorani et al1 reported that irregular pigmentation at the level of the retinal pigment epithelium , most often manifested as a speckling or granularity of the retinal pigment epithelium , was distributed diffusely in the mid peripheral / peripheral zone.1 the few reports concerning macular changes in alagille syndrome describe symmetric , well circumscribed , horizontally oval areas of speckled reddish brown macular discoloration,2 pigment clumping in the macula,3 and circumpapillary geographic chorioretinal atrophy with half - moon shapes involving the macular area.4 however , chorioretinal atrophy involving the macular area is rare . in this case ,
diffuse choroidal hypopigmentation with increased visibility of the choroidal vessels and a sleep mask - like hypofluorescent area corresponding to chorioretinal atrophy as examined by fundus autofluorescence were detected . to our knowledge , there are no similar cases in the literature of alagille syndrome presenting a chorioretinal atrophy involving the macula with a sleep mask appearance as examined by oct and fundus autofluorescence .
a possible explanation for chorioretinal atrophy in alagille syndrome is failure of absorption of fat - soluble vitamins .
romanchuk et al5 suggested that failure of fatsoluble vitamin absorption plays a major role in the evolution of retinopathy in alagille syndrome .
the retinoid cycle is a vitamin a - linked metabolic circuit which occurs between the outer segment of the photoreceptor and the retinal pigment epithelium to maintain visual function .
low serum vitamin e levels have been well documented in children with malabsorption due to cholestatic liver diseases.6 the role of vitamin e in vision is less clear , but it is believed to have an important protective function as a lipid antioxidant for the extremely high concentrations of polyunsaturated fatty acids found in the outer segments .
increases in the number of lipofuscin granules in the cytoplasm of retinal pigment epithelium in vitamin e - deficient rats were observed.7 the retinal pigment epithelium cells of the peripheral and equatorial zone contain large numbers of lipofuscin granules within their cytoplasm.8 thus , both of these vitamins are believed to be important in maintaining the integrity of the photoreceptor outer segments and the retinal pigment epithelium cells .
fundus autofluorescence has been investigated in various fundus diseases associated with changes in the retinal pigment epithelium .
fundus autofluorescence is presumed to derive from lipofuscin in retinal pigment epithelium cells and to represent metabolic activity of retinal pigment epithelium involving turnover of photoreceptor outer segments .
hypofluorescence is thought to correspond to areas of decreased metabolism resulting from photoreceptor and/or retinal pigment epithelium atrophy , and has been used as a marker of the integrity of the retinal pigment epithelium / photoreceptor complex .
the peculiar findings in this patient were abnormalities of the inner segment / outer segment junction and the outer segments of photoreceptors , suggestive of loss of structural integrity of the photoreceptors .
therefore , we suggest that transient hypovitaminosis due to alagille syndrome early in life might contribute to the retinal degeneration seen in this case .
finally , anatomic evidence of retinal degeneration induced by vitamin a or e deficiencies suggests that the structural disruption of photoreceptors is more advanced in cones and most pronounced in the macula , with lesser involvement of the peripheral retina.9 however , it is not clear whether our case represents a congenital or acquired change due to alagille syndrome .
we report the first case in the literature of chorioretinal atrophy involving the macula in an 11-year - old girl with alagille syndrome , as examined by optical coherence tomography , and fundus autofluorescence imaging . 
 funduscopy revealed diffuse choroidal hypopigmentation with increased visibility of the choroidal vessels and symmetric , well circumscribed macular discoloration . 
 anomalous oblique configuration of the optic disc and peripapillary tortuous vessels were also detected . 
 optical coherence tomography demonstrated decreased retinal thickness , especially the outer retinal layer , and the photoreceptor inner segment / outer segment junctions were irregular and discontinued , corresponding to macular discoloration . 
 fundus autofluorescence imaging clearly defined hypofluorescent areas in the peripapillary regions that extended along the macula and had a sleep mask appearance . 
 we suggest that transient hypovitaminosis due to alagille syndrome early in life might contribute to the retinal degeneration seen in this case .