title: Cyclopia: an epidemiologic study in a large dataset from the International Clearinghouse of Birth Defects Surveillance and Research.
abstract: Cyclopia is characterized by the presence of a single eye, with varying degrees of doubling of the intrinsic ocular structures, located in the middle of the face. It is the severest facial expression of the holoprosencephaly (HPE) spectrum. This study describes the prevalence, associated malformations, and maternal characteristics among cases with cyclopia. Data originated in 20 Clearinghouse (ICBDSR) affiliated birth defect surveillance systems, reported according to a single pre-established protocol. A total of 257 infants with cyclopia were identified. Overall prevalence was 1 in 100,000 births (95%CI: 0.89-1.14), with only one program being out of range. Across sites, there was no correlation between cyclopia prevalence and number of births (r = 0.08; P = 0.75) or proportion of elective termination of pregnancy (r = -0.01; P = 0.97). The higher prevalence of cyclopia among older mothers (older than 34) was not statistically significant. The majority of cases were liveborn (122/200; 61%) and females predominated (male/total: 42%). A substantial proportion of cyclopias (31%) were caused by chromosomal anomalies, mainly trisomy 13. Another 31% of the cases of cyclopias were associated with defects not typically related to HPE, with more hydrocephalus, heterotaxia defects, neural tube defects, and preaxial reduction defects than the chromosomal group, suggesting the presence of ciliopathies or other unrecognized syndromes. Cyclopia is a very rare defect without much variability in prevalence by geographic location. The heterogeneous etiology with a high prevalence of chromosomal abnormalities, and female predominance in HPE, were confirmed, but no effect of increased maternal age or association with twinning was observed.
authors: Estudo Colaborativo Latino Americano de Malformações Congênitas at Departamento de Genética, Instituto de Biologia, Rio de Janeiro, Brazil. orioli@centroin.com.br
authors: Iêda M
authors: IM
authors: Orioli
authors: Emmanuelle
authors: E
authors: Amar
authors: Marian K
authors: MK
authors: Bakker
authors: Eva
authors: E
authors: Bermejo-Sánchez
authors: Fabrizio
authors: F
authors: Bianchi
authors: Mark A
authors: MA
authors: Canfield
authors: Maurizio
authors: M
authors: Clementi
authors: Adolfo
authors: A
authors: Correa
authors: Melinda
authors: M
authors: Csáky-Szunyogh
authors: Marcia L
authors: ML
authors: Feldkamp
authors: Danielle
authors: D
authors: Landau
authors: Emanuele
authors: E
authors: Leoncini
authors: Zhu
authors: Z
authors: Li
authors: R Brian
authors: RB
authors: Lowry
authors: Pierpaolo
authors: P
authors: Mastroiacovo
authors: Margery
authors: M
authors: Morgan
authors: Osvaldo M
authors: OM
authors: Mutchinick
authors: Anke
authors: A
authors: Rissmann
authors: Annukka
authors: A
authors: Ritvanen
authors: Gioacchino
authors: G
authors: Scarano
authors: Elena
authors: E
authors: Szabova
authors: Eduardo E
authors: EE
authors: Castilla
mesh_terms: D000328:Adult; D000569:Americas / Q000453:epidemiology; D001315:Australia / Q000453:epidemiology; D035843:Biomedical Research / Q000639:trends; D002681:China / Q000453:epidemiology; D025063:Chromosome Disorders / Q000235:genetics; D002882:Chromosomes, Human, Pair 13 / Q000235:genetics; D000013:Congenital Abnormalities / Q000453:epidemiology* / Q000235:genetics / Q000473:pathology; D016021:Epidemiologic Studies; D005060:Europe / Q000453:epidemiology; D005124:Eye Abnormalities / Q000453:epidemiology* / Q000235:genetics / Q000473:pathology; D005260:Female; D016142:Holoprosencephaly / Q000453:epidemiology / Q000235:genetics / Q000473:pathology; D006801:Humans; D007231:Infant, Newborn; D007391:International Cooperation; D008297:Male; D011159:Population Surveillance / Q000379:methods*; D011247:Pregnancy; D015995:Prevalence; D012042:Registries; D014314:Trisomy / Q000235:genetics; D000073839:Trisomy 13 Syndrome