Surgical management of foramina parietalia permagna.

Enlarged parietal foramina are rare congenital skull defects identified on physical examination and confirmed radiographically. They are round or oval defects situated on each parietal bone approximately 1 cm from the midline and 2 to 3 cm superior to the lambdoid suture. Although small parietal foramina are common variants in up to 60% to 70% of normal skulls, large parietal foramina ranging from 5 mm to multiple centimeters are less common, with a prevalence of 1:15,000 to 1:25,000. We present a case series of four patients with large persistent parietal foramina managed surgically for the correction of this deformity. Two infants were treated with autologous calvarial bone grafts, and two were treated with a mesh plating system and hydroxyapatite. No patient developed any perioperative complications. No perioperative or delayed infections occurred in our patient population. The mean postoperative follow-up was 36 months. One patient required a second procedure with methylmethacrylate because of late bone graft failure, whereas the others were successfully treated by the initial procedure. Foramina parietalia permagna, otherwise known as fenestrae parietals symmetricae, enlarged parietal foramina, giant parietal foramina, or Catlin marks, are a rare clinical entity. A spontaneous decrease in the size of these defects with growth of the infant has been reported, but this closure is usually incomplete. Surgical intervention of persistent large foramina protects the child against potential injury to the underlying brain. We advocate cranioplasty for active young children and those at risk for injury (i.e., seizure disorder) to decrease the risk for potential intracranial injury.