An anatomical study of pneumatized crista galli

Abstract

The literature data on the incidence of pneumatization of the crista galli based on patients' computed tomography (CT) scans ranges from 3 to 37.5%. This study investigated for the first time the incidence of crista galli pneumatization based on CT scans of human skulls. The study examined 102 randomly selected human skulls (≥20 years of age; 76 males, 26 females). Skulls were scanned in a fixed position using cone beam computed tomography (CBCT) with a field of view of 145 × 130 mm and an isotropic voxel size of 0.25 mm. The scans were recorded in Digital Images and Communications in Medicine format. The CBCT images were analyzed using OnDemand3DTM software. A 2-mm contiguous slice thickness was used in the axial and coronal planes. The width, length, and height (cranial-caudal dimension) of the pneumatized space within the crista galli were measured. The crista galli was found to be pneumatized in even 68 (66.6%) of the 102 skulls. Two types of pneumatized crista galli (PCG) were identified: PCG alone (surrounded by bony walls) and PCG + spongiosis (surrounded by spongy bone). Of the 68 pneumatized skulls, 31 were PCG alone (45.58%) and 37 were PCG + spongiosis (54.42%). The pneumatized regions had a width of 0.9-6.6 mm, length of 2.8-12.9 mm, and height of 3.6-17.1 mm. No statistically significant differences have been found regarding the sex and age. Regarding the proportions of pneumatization, the three types of crista galli have been determined resulting in new, practical classification: type S (small), type M (moderate), and type L (large). The crista galli is not always a compact bone; in some cases, it is filled with spongy bone or pneumatized. In respect of proportions of pneumatization, there are three types of pneumatized crista galli: small, moderate, and large. Pneumatized crista galli can play an important role in clinical work, both as an inflamed sinus or other pathologies (sinusitis cristae galli, mucocoelae) or as a morphologic barrier in neurosurgical approaches to some tumors of the anterior skull base.

The relationship between the pneumatization patterns of the frontal sinus, crista galli and nasal septum: a tomography study

“…lesions in the anterior skull base and cerebrospinal fluid (CSF) leak (13,17). The FS is a nascent pneumatization in the fourth or fifth week of gestation and reaches its final size at the age of 20 years.…”

“…The CG, which limits the olfactory fossa medially and projects on the midline of the cribriform plate, superiorly originates from the ethmoid bone during foetal period and turns into a █ INTRODUCTION T he frontal sinus (FS) and the less common types of extrasinusal pneumatizations including the crista galli (CG) and nasal septum (NS), are in close localisation and communicate with each other if pneumatization occurs. These neighbouring structures are critical landmarks during anterior skull base surgery and endoscopic sinus surgery (ESS) (12,13). Computed tomography (CT) scan provides extremely good opportunities for the evaluation of these bony structures.…”

“…However, the main inferences based on radiological anatomy studies were the fact that 2.4%-37.5% of the pneumatized CG, also referred to as the sinus crista galli (SCG), mostly drains into the FS or ethmoid sinus. The drainage pathway of the CG can play a role in disseminating of frontal pathologies into the CG (9,10,13). In clinical settings, nasal dermoids, congenital midline nasal defects, mucocele and iatrogenic CSF leak can be associated with the SCG.…”

Pneumatized Crista Galli: A Histopathologic Study

“…The authors themselves were surprised by the high incidence, as they concluded that it was easier to judge the degree of pneumatization in human skulls, given that the tissues in spongy bone are replaced with air. 16…”

“…15 All of the previous studies investigating PCG incidence were done by analyzing the CT scans of symptomatic patients, with the exception of Mladina et al, as they analyzed the cone beam CT images of human skulls. 16…”