Cyclopia: Facial deformity indicating severe holoprosencephaly with imaging findings of brain: A case report.

Holoprosencephaly results from incomplete separation of the cerebral hemispheres. Cyclopia is a facial manifestation of Holoprosencephaly, characterized by a midline single orbit and proboscis. Prenatal diagnosis is done by ultrasonography and can be supplemented by MRI. This case uniquely presents ultrasound and gross morphology correlation of cyclopia in a resource limited setting, and a correlation between facial features, intra-cranial anatomy, and lifespan. We report a 39-year-old gravida 3 para 2 woman with a history of alcohol consumption who presented for her first antenatal checkup at 19 weeks of gestation. Ultrasound revealed a single lateral ventricle with fused thalami, absent orbital structures, and a midline cystic protrusion (proboscis). After thorough counseling, pregnancy was terminated, and cyclopia was confirmed on gross inspection. Karyotyping and fetal echocardiography were not done due to parental preference. Alobar holoprosencephaly, the most severe subtype, is diagnosed by identification of single ventricle and associated facial anomalies. Lobar holoprosencephaly, however, requires coronal imaging to demonstrate absence of cavum septum pellucidum and fusion of frontal horns. The severity of facial anomalies correlates with underlying brain malformations. Chromosomal anomalies, maternal diabetes, infections, and teratogenic exposures like alcohol are known risk factors. Differential diagnoses include proboscis lateralis, midline encephaloceles and frontonasal dysplasia. This case highlights the prognostic significance of facial and brain anomalies and diagnostic utility of prenatal ultrasound in diagnosing holoprosencephaly underscoring the necessity of timely prenatal visits. Definitive genomic studies were not feasible, but maternal alcohol consumption can be considered as a possible risk factor.