False and true accessory infraorbital foramina, and the infraorbital lamina cribriformis

Accessory infraorbital foramen location using cone-beam computed tomography

Background

Accessory infraorbital foramen (AIOF) can change the normal course of emerging branches of the infraorbital nerve and blood vessels exiting the infraorbital foramen (IOF). This study aimed to examine the AIOF, number of foramina, and their position in relation to IOF using cone-beam computed tomography (CBCT).

Methods

We performed a retrospective CBCT assessment of hospital records between January 2018 and August 2022. The CBCT of 507 patients were examined to extract information on the prevalence, number, position, linear distance from the IOF, and diameter of AIOF in relation to demographic factors. Descriptive statistics were used to evaluate the prevalence of AIOF. Mean and standard deviation were used to calculate the linear distance and diameter of the AIOF, respectively. The AIOFs, its distribution, and number were compared between sexes and sides using the chi-square test. The independent t-test and Mann-Mann-Whitney test were used to compare the mean difference between the sexes and sides. Statistical significance was set at P < 0.05.

Results

In this current study, the prevalence of AIOF was 7.1% (36 of the 507 patients). Additionally, the current study examined the number of foramina using a single foramen on each side and double foramina located bilaterally at a distance from the AIOF to the IOF. The mean AIOF diameter was also studied, and the AIOF position with respect to the IOF on CBCT was superomedial or inferomedial. There were no statistically significant associations between any of the parameters assessed in this study when comparing sex and sides.

Conclusions

A greater number of patients with AIOF presented with a single foramen and unilateral occurrence, without a statistically significant difference. The AIOF was most commonly located superomedial to the IOF.

Prevalence of canalis sinuosus and accessory canals of canalis sinuosus on cone beam computed tomography: a systematic review and meta-analysis

The aim of this systematic review was to determine the prevalence of the canalis sinuosus (CS) and accessory canals of the canalis sinuosus (ACCS) as identified on cone beam computed tomography (CBCT). Online searches were conducted in the MEDLINE (via PubMed), Scopus, LILACS, Cochrane CENTRAL, Web of Science, and SIGLE (via OpenGrey) databases. Primary studies that determined the prevalence of canalis sinuosus and/or its anatomical variations using CBCT were included. The risk of bias assessment was performed using the AQUA tool. The quality effects model using double arcsine transformation was used for the meta-analysis of prevalence. Heterogeneity, publication bias, and sensitivity analyses were performed. Of 3237 initial results, 17 papers were included for systematic review. The meta-analysis comprising 1994 patients showed a pooled prevalence of CS of 0.80 (95% confidence interval (CI) 0.51-0.99; P = 0.001; I² = 99%). Publication bias analysis revealed minor asymmetry (LFK index 1.84). The meta-analysis of 4605 patients showed a pooled prevalence of ACCS of 0.54 (95% CI 0.38-0.69; P = 0.001; I² = 99%). The sensitivity analysis showed a pooled prevalence of ACCS of 0.53 (95% CI 0.32-0.74; P = 0.001; I² = 99%) for studies with ≥ 1000 patients and 0.55 (95% CI 0.33-0.76; P = 0.001; I² = 98%) for studies with< 1000 patients. Canalis sinuosus showed a pooled prevalence of 0.80 and ACCS showed a pooled prevalence of 0.54; hence both should be considered as anatomical structures, which means that they are present in most people. Surgeons must be aware of the CS and ACCS on CBCT analysis during pre-surgical planning. PROSPERO REGISTRATION NUMBER: CRD42020154195.