Sex estimation with morphometric and morphological characteristics of the crista galli

PURPOSE

The purpose of the present study was to analyze the dimensions of the crista galli (CG) in preserved skulls, and to examine the role of the morphometry and morphology of the CG on the sex estimation.

METHODS

Anteroposterior, superoinferior, and laterolateral diameters of the CG were measured of 207 preserved adult skulls of Anatolia origin with known sex (108 males, 99 females) in the Anatolian population. CG were morphologically classified into three types according to the dimensions. The success of CG dimensions in sex determination was evaluated with ROC analysis, and univariate and multivariate binary logistic regression analysis. The relationship between morphological types of the CG and sex was analyzed with the Chi-square test.

RESULTS

The anteroposterior and superoinferior diameters of the CG significantly were longer in males than females while the laterolateral diameter of the CG was wider in females (p < 0.001). Superoposterior diameter (88.4%) of the CG showed higher sex classification accuracy for sex estimation compared to the laterolateral (82.6%) and anteroposterior diameters (80.6%). When all three parameters were used together, the sex classification accuracy rate was 94.2%. The presence of ossified and tubular types of CG identified the male sex with 85% and 74.6% accuracy rates, respectively while teardrop type CG identified female sex with a 72.2% accuracy rate.

CONCLUSION

CG exhibits sexual dimorphism both morphometrically and morphologically. The height, length, and width measurements and the morphological types of CG can be used in sex determination directly from the skull with high accuracy rates.

Dural arteriovenous fistula with crista galli erosion in a patient with suspected sinusitis

Dural arteriovenous fistula (dAVF) of the anterior cranial fossa is an aggressive entity with a high risk of intracranial hemorrhage. A 38-year-old woman presented to our institution with nasal obstruction and discharge. Computed tomography (CT) scans performed for suspected sinusitis revealed erosion of the crista galli predominantly on the left side. The frontal and ethmoidal sinuses adjacent to the crista galli were clear and did not communicate with the crista galli. Contrast computed tomography scans revealed ectatic vessels adjacent to the crista galli, coursing on the cortical surface. Cerebral angiography identified an anterior fossa dAVF supplied by the bilateral anterior and posterior ethmoidal arteries and drained by the dilated cortical veins. Based on these findings, we assumed that long-term compression by the pulsatile draining veins caused the erosion. The patient underwent successful microsurgical disconnection procedure of the dAVF with an uneventful postoperative course. We concluded that external erosion of the crista galli could be a sign of aggressive dAVF and requires careful examination.

Classification of crista galli pneumatization and clinical considerations for anterior skull base surgery

Cerebrospinal fluid (CSF) leakage caused by frontal sinus exposure is a serious complication in the basal interhemispheric approach (BIHA). Crista galli pneumatization (CGP) is often observed on preoperative computed tomography (CT) scan. The aim of this study was to classify and describe variations in anatomical measurements of CGP. We examined CT images of 300 patients with brain tumors to assess the morphology and incidence of CGP. Crista galli were classified according to their location relative to the cribriform plate and the presence of pneumatization. The paranasal sinuses were investigated as the origin of CGP. We assessed 24 patients using the BIHA for skull base tumors; these patients were included as clinical cases to assess the range of skeletonization of the crista galli and determine the route of CSF leakage in the other 276 patients. CGP was found in 28/300 CT scans, including upper, middle, and lower type CGPs. The origin of CGPs was the frontal sinus or ethmoid sinus. All CGPs were localized in the anterior half of the crista galli. In the 24 consecutive clinical cases, there were 13 tuberculum sellae meningiomas, 3 craniopharyngiomas, and 8 with other pathologies. The preoperative crista galli height was 12.3 mm and the distance from the top of the skeletonization to the cribriform plate was 5.2 mm. CGP originating from the paranasal sinuses can lead to CSF leakage. In cases where CGP originates from the ethmoid sinus, care should be taken to seal the exposed crista galli intradurally.

A possible venous connection between the cranial and nasal cavity

PURPOSE

The foramen cecum (FC) is a fine bony canal with the aperture located immediately anterior to the crista galli (CG). The venous structures in the regions of the FC and CG have been inconsistently described and are not well understood. Here we explore these veins using magnetic resonance imaging.

MATERIALS AND METHODS

We enrolled 101 patients who underwent contrast examinations and exhibited intact skin, skull, dura mater, and intracranial dural sinuses. Imaging data were obtained as thin-sliced, seamless sagittal sections and were transferred to a workstation for analysis.

RESULTS

In 84 % of the patients, tubular-shaped venous extensions arose from the rostral end of the falx cerebri and were confirmed to lie in the FC. These extensions were supplied by the superior sagittal sinus or the frontal cortical vein, and were classified into four types: rudimental slight projections, short and straight extensions, long and straight channels, and long and tortuous channels. Furthermore, 27.7 % of the patients exhibited a distinct venous channel between the venous extension in the FC and the median vestibular submucosa of the nasal cavity. Among these channels, 81.5 % were connected to the vein lying in the FC via a short channel that vertically pierced the CG.

CONCLUSIONS

The FC contains tubular-shaped venous extensions that are supplied by the rostral end of the superior sagittal sinus or the frontal cortical vein. The cranial cavity, FC, and nasal cavity may be connected by a venous channel.