Surgical Treatment of Cloverleaf Skull Deformity under the Concept of Comprehensive Cranioplasty

Lee, Eui Tai

Abstract

Cloverleaf skull deformity is not a syndrome or a disease, but one of the most severe forms of craniosynostosis which may or may not be associated with various syndromes such as achondroplasia, Crouzon's disease or Apert's syndrome. This deformity accompanies serious elevation of intracranial pressure which necessitates early surgical intervention to avoid death, mental retardation, and decreased visual acuity. Until recently, near total calvariectomy, staged anterior and posterior cranioplasty, and total calvarial remodelling using barrel stave osteotomy are used, but result in limited success only. High mortality and morbidity rates are related to multiple operations with long operation time in young age, difficulties in maintenance of patient position, and persistent deformity and bony defect. Therefore, the authors integrated various cranioplasty techniques originally developed for simple skull deformities and modified them according to the exact nature of the individual deformities under the unique original concept of 'Comprehensive Cranioplasty'. A fourteen week old male patient presented with trilobed skull shape, bony constriction band between the lobes, prominent forehead, flat occiput, and enlarged scalp veins. Three dimensional CT scan revealed premature fusion of total cranial sutures including metopic, sagittal, bilateral coronal, lambdoidal, and squamosal sutures. To release all the closed sutures and to correct the deformity in three dimensions, we adopted various cranioplasty techniques under the concept of comprehensive cranioplasty as follows; first, release of all cranial sutures by frontal craniotomy, bilateral temporal craniotomy, bilateral parasagittal strip craniectomy, and bilateral partial lambdoidal strip craniectomy, second, lengthening of skull anteroposterior dimension by fronto- orbital advancement and modified calvarial remodelling (infracture & outfracture), third, reduction of skull width by barrel stave osteotomy and bilateral parasagittal strip craniectomy, four, reduction of skull height by modified calvarial remodelling and split and transposition of craniotomized frontal bone segment, which also correct flat occiput and prominent forehead, respectively. All the operative procedures were performed under supine position. Without modified prone position, posterior cranium could be exposed to the inion level and it is sufficient to do the partial lambdoidal strip craniectomy and backcut osteotomy. We think modified prone position is not needed even in cases of posterior cranial deformity unless complete removal, ex vivo remodelling, and reattachment of occipital cranium are necessary. Eighteen months after the operation, the patient shows significant growth and improvement on both functional and aesthetic aspects despite persistent microcephalus, and insufficient reduction in cranial height and width. In summary, the authors experienced a quite satisfactory result both functionally and aesthetically in a complex cloverleaf skull deformity patient by combination and modification of previously developed various cranioplasty techniques according to the exact nature of the individual deformities under the concept of comprehensive cranioplasty.