Surgical Management of Foramina Parietalia Permagna

Abstract

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.

Enlarged parietal foramina: a review of genetics, prognosis, radiology, and treatment

“…Education of teachers and parents is advised to allay anxiety related to the disease and to eliminate anxiety about risk of penetrating injury to unprotected cerebrum [25]. Cranioplasty with autologous calvarial bone grafts or mesh plating systems with hydroxyapatite or methylmethacrylate is recommended for those at risk for injury, such as active young children and those with seizure disorders [11,19]. Imaging to assess for accompanying venous anomalies is imperative prior to any surgical intervention [5].…”

“…There is no described correlation between the size of the defect and the likelihood of having an associated brain abnormality [5]. A spontaneous decrease of the defect with growth of the infant has been observed, but closure is frequently incomplete [11].…”

A case of an extremely large accessory bone with unusual sutures and foramina parietalia permagna in multiple premature craniosynostoses

“…For specific diagnosis the patient was admitted to our institution where three-dimensional computed tomography (Girod et al, 2001), revealed partial premature fusion of the lambdoid sutures (bilateral posterior plagiocephaly), complete fusion of the metopic suture (trigonocephaly) and total absence of a sagittal suture. In the occipital region, lateral to the midline, two atypical foramina parietalia permagna, also known as Catlin-marks (Kortesis et al, 2003) were found, and several extensively dilated emissary veins (Fig. 1).…”

Congenital Scalp and Calvarial Deficiencies: Principles for Classification and Surgical Management

“…Spontaneous decrease in the size of these defects with growth of the infant may occur, but this closure is often incomplete in larger defects. 19 This anomaly is caused by a failure of completion of ossification within the parietal bones. Normally, ossification begins in a single center of the parietal bones as early as the seventh week of fetal life and is normally complete by the seventh month.…”

“…Kortesis et al recently reported on the successful use of splitthickness calvarial grafts in children 3 years of age or older with foramina parietalia permagna. 19 In older patients, splitting of the inner and outer tables allows for increases up to 350 percent in the size of the originally harvested calvaria. 52 Full-thickness bone grafts have also been used in our practice.…”