Parietal Bone Agenesis and Associated Multiple Congenital Anomalies

Abstract

Congenital defects of the calvaria in general and the parietal bones in particular are rare diseases. The latter are of three kinds: 1) cranioschisis, 2) craniodysostosis, and 3) foramina parietalia permagna (FPP). Here, we describe an exceptional anomaly, namely, complete absence of one parietal bone and dysplasia of the other. Agenesis has been reported twice before in the literature. In these cases, the calvarial defect was the only congenital anomaly. In contrast, the patient described in this article exhibited many other congenital deformities, namely, iris coloboma, facial dysmorphism, a large ventricular septal defect of the heart, and a horseshoe kidney. Some of these deformities are associated with neural crest development. Chromosomal analysis was normal in both blood and fibroblasts, and fluorescent in situ hybridization analysis failed to demonstrate a 22q11 deletion as seen in DiGeorge syndrome, a neural crest-related disease complex. Since 2000, the third group of congenital defects of the parietal bones, FPP, has been associated with mutations of the MSX-2 gene. In our case, a genetic analysis of this gene was performed, but no mutations or deletions of MSX-2 were detected.

Parietal bone agenesis and athelia in retinoic acid embryopathy: An expansion of the phenotype

“…Additional features included a low frontal hairline, low-set ears, right iris coloboma, epicanthal folds, short neck, complex congenital heart malformation, and a horseshoe kidney. The investigators performed a karyotype as well as fluorescent in situ hybridization (FISH) of the 22q11 region, and both were normal (de Heer et al, 2003). It was not reported whether there might have been any history of isotretinoin exposure, although the features are certainly reminiscent of those seen in our case.…”

“…The bilateral parietal bone agenesis identified in this case has not previously been reported in retinoic acid embryopathy. Parietal bone agenesis is itself an exceedingly rare congenital anomaly, only reported a handful of times in the medical literature (de Heer, van Nesselrooij, Spliet, & Vermeij-Keers, 2003;Dunn, Stout, & Dix, 1991;Sela, Sahar, & Lewin-Epstein, 1979;Spear, 2006). One such report describes a female neonate who presented with right parietal bone agenesis, right temporal bone hypoplasia, and left parietal bone F I G U R E 3 Fetal autopsy images demonstrating bilateral parietal bone agenesis.…”

Metopic and Sagittal Suture Cranioschisis Mimicking Bilateral Parietal Bone Agenesis in a Hydrocephalic Newborn: A Case Report

“…These lesions are divided into three subjects: 1) cranioschisis, 2) craniodysostosis and 3) foramina parietalia permagna. Parietal bone agenesis may be a fourth entity (2).…”

Parietal bone agenesis with gracile bones and splenic hypoplasia/aplasia: Clinico‐pathologic report and differential diagnosis with review of cranio‐gracile bone syndromes, “osteocraniostenosis” and Kleeblattschädel

“…Occasional reports describe parietal bones as particular, even selective, sites of malformations, including agenesis [Wuyts et al, 2000; deHeer et al, 2003; Spruijt et al, 2005; Cunningham et al, 2006].…”