HOLOPROSENSEFALİ: ALTI OLGUDA İLİŞKİLİ MALFORMASYONLAR VE KLİNİK BULGULAR

Öz

Amaç: Holoprosensefali (HPE), erken gestasyonel dönemde ön beynin tamamen veya yetersiz ayrılmasıyla karakterli beynin yapısal bir anomalisidir. HPE’lerin yaklaşık %80’nine, karakteristik kranyofasyal anomaliler eşlik eder. HPE, yaklaşık 16.000 canlı doğumda ve 250 embryoda bir ortaya çıkan, insanda sık görülen beyin defektidir. Sıklıkla, ilk kez gebelikteki ultrason sırasında tanımlanır. Hafif ve orta derecede beyin anomalisi olan infantlar ise yaşamın ilk yılının sonuna kadar tanı alamayabilirler. Çalışmamızın amacı kliniğimizde HPE tanısı alan olgulara eşlik eden ek anomalileri incelemek ve bu bulguları literatür ile eşliğinde gözden geçirmektir. 

Olgular: Hastanemiz patoloji kayıtlarından 6 adet HPE tanısı alan vaka izlendi. Olguların klinik, genetik ve yapısal anomalileri değerlendirildi. 

Sonuç: Oldukça küçük başa sahip olan fetüslerde sonografik inceleme çok zor olabilir ve HPE’ye ait bulgular kolaylıkla, ilk trimesterde gözden kaçabilir. HPE’ye ait bulguların saptanabilmesi için ilk trimesterde fetusa ait serebral yapıların çok dikkatli incelenmesi önemlidir.

Anahtar Kelimeler

• Alobar
• holoprosensefali
• fetal anomali

HOLOPROSENCEPHALY: CLINICAL FINDINGS AND RELATED MALFORMATIONS IN SIX CASES

Öz

Objective: Holoprosencephaly (HPE) is a morphological anomaly of the brain that is characterised with unsuccessful or incomplete separation of the forebrain in early gestation. Approximately 80% of HPE cases is accompanied by a spectrum of characteristic craniofacial anomalies. HPE is a common forebrain defect in humans, with a prevalence of 1:250 in embryos and 1:16,000 among live-born infants. HPE is usually diagnosed by gestational ultrasound examination. Infants with mild or moderate brain anomalies may not be diagnosed until the first year of life. The aim of the study was to search for the defects of HPE in our cases and discuss the findings in view of the literature.

Cases: We identified 6 patients with HPE from our hospital database. We herein describe the clinical, genetic and structural abnormalities of the fetuses with HPE.

Conclusion: The ultrasonographic examination of the brain in fetuses with a small head may be difficult and the first trimester features of HPE can be easily overlooked. It is important to examine cerebral structures of fetuses very carefully in the first trimester to detect the HPE features

Anahtar Kelimeler

• Alobar
• holoprocencephaly
• fetal anomaly

Kaynakça

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