Extratemporal Facial Nerve Interconnections and Trunk's Variability: A Systematic Review with Meta-Analysis.

BACKGROUND: The present systematic review with meta-analysis is a significant contribution to the understanding of the morphological variability of the facial nerve (FN) extratemporal segment, i.e., the facial trunk (FT) variability, its division, and terminal branching patterns. The study also provides a comprehensive overview of the clinical significance of the FN extracranial division. METHODS: Four online databases were utilized to conduct the systematic review according to evidence-based anatomy guidelines. A meta-analysis of the studies included was carried out using R programming software. The combined prevalence of the FN variants was calculated, along with subgroup and cumulative analysis. RESULTS: From the systematic review, 29 studies were retrieved as eligible for our initial purpose. However, 19 studies followed the same classification system and were selected for the meta-analysis, with a total sample of 2453 nerves. The most common pattern of the FN morphology was the FT bifurcation (typical pattern), with a pooled prevalence of 94.1% and a single interconnection (IC) between the temporofacial and cervicofacial branches (23.1% pooled prevalence). Two ICs between these branches were the rarest pattern (8.9% pooled prevalence). CONCLUSIONS: Our findings underscore the extensive morphological variability of the FN extratemporal anatomy, which has led to confusion among researchers. While several classification systems have been developed, none accurately represent the typical and variant anatomy. Our meta-analysis provided a small range between 8.9-23.1% for the rarest and most common pattern; thus, diversity is the rule. Therefore, it is not safe to conclude the typical morphology of FN extratemporal anatomy for its whole distribution before the FT's division (proximally) and its terminal branches (distally). Nevertheless, the bifurcation of the FT can be considered the typical morphology, and it is far more constant than the distal branching pattern. These findings have significant implications for surgical procedures, particularly parotidectomy, where surgeons must exercise utmost caution due to the potential clinical implications of FN injury.

The superior thyroid artery origin pattern: a systematic review with meta-analysis.

PURPOSE: The current systematic review with meta-analysis aimed to investigate the pooled prevalence of the superior thyroid artery (STA) pattern of origin (distinct or fused-common origin with adjacent arteries in the form of a common trunk). The standard and uncommon variants were also studied, considering the STA's exact surface of origin and the relationship with the upper border of the thyroid cartilage (TC, reference point), considering the laterality effect. Thus, the STA topographical anatomy was considered. METHODS: An evidence-based systematic review with meta-analysis was performed according to the PRISMA 2020 guidelines. A literature search was conducted in four online databases using specific keywords, the pooled prevalence was calculated using statistical analysis in the R programming language, and multiple subgroup analyses were performed. RESULTS: The most common distinct origin of the STA was from the external carotid artery (ECA) (56.94% pooled prevalence, 95%CI: 50.89-62.89), and the rarest one was from the internal carotid artery (ICA) (< 0.01%, 95%CI: 0.00-0.00). Common trunks were also investigated, with the thyrolingual trunk emanating from the ECA estimated at 0.61% (95%CI: 0.21-1.14), representing the most common. Subgroup analysis based on the nationality, type of study, and sample size, as well as a comparison between left and right sides and males and females, were investigated. CONCLUSIONS: The most common STA origin was estimated as the ECA, the medial surface of origin, and above the TC upper border. Adequate knowledge of STA origin is paramount for surgeons, especially during thyroidectomy, not to cause iatrogenic injury to the external branch of the superior laryngeal nerve.

Right-Sided Aortic Arch: A Computed Tomography Angiography Investigation, A Systematic Review with Meta-Analysis.

Background/Objectives: The right-sided aortic arch (RAA) is an uncommon variation of the aortic arch (AA), characterized by the aorta crossing over the right main bronchus. In the RAA, the descending aorta can be found on either the right or left side of the spine. The current study comprises a comprehensive retrospective computed tomography angiography (CTA) investigation into the prevalence of the RAA within the Greek population. Additionally, we will conduct a systematic review and meta-analysis to elucidate both common and rare morphological variants of the RAA. This research is significant as it sheds light on the prevalence and characteristics of the RAA in a specific population, providing valuable insights for clinical practice. Methods: Two hundred CTAs were meticulously investigated for the presence of a RAA. In addition, the PubMed, Google Scholar, and Scopus online databases were thoroughly searched for studies referring to the AA morphology. The R programming language and RStudio were used for the pooled prevalence meta-analysis, while several subgroup analyses were conducted. Results: Original study: A unique case of 200 CTAs (0.5%) was identified with an uncommon morphology. The following branches emanated from the RAA under the sequence: the right subclavian artery (RSA), the right common carotid artery (RCCA), the left common carotid artery (LCCA), and the left vertebral artery (LVA) in common origin with the aberrant left subclavian artery (ALSA). The ALSA originated from a diverticulum (of Kommerell) and followed a retroesophageal course. Systematic Review and Meta-Analysis: Sixty-two studies (72,187 total cases) met the inclusion criteria. The pooled prevalence of the RAA with a mirror-image morphology was estimated at 0.07%, and the RAA with an ALSA was estimated at <0.01%. Conclusions: AA anomalies, specifically the RAA, raise clinical interest due to their coexistence with developmental heart anomalies and possible interventional complications. Congenital heart anomalies, such as the Tetralogy of Fallot and patent foramen ovale, coexisted with RAA mirror-image morphology.

The anterior communicating artery variants: a meta-analysis with a proposed classification system.

Morphological and morphometric variants of the anterior communicating artery (AComA) have been described by multiple studies; however, a complete classification system of all possible morphological variants with their prevalence is lacking. The current systematic review with meta-analysis combines data from different databases, concerning the AComA morphological and morphometric variants (length and diameter). Emphasis was given to the related clinical implications to highlight the clinical value of their knowledge. The typical AComA morphology occurs with a pooled prevalence (PP) of 67.3%, while the PP of atypical AComA is 32.7%. The identified AComA morphological variants (artery's hypoplasia, absence, duplication, triplication, differed shape, fenestration, and the persistence of a median artery of the corpus callosum- MACC) were classified in order of frequency. The commonest presented variants were the AComA hypoplasia (8%) and the anterior cerebral artery (ACA) fusion (5.9%), and the rarest ones were the MACC persistence (2.3%), and the AComA triplication (0.7%). The knowledge of those variants is essential, especially for neurosurgeons operating in the area. Given the high prevalence of AComA aneurysms, an adequate and complete classification of those variants is of utmost importance.

The Anterolateral Ligament of the Knee Is a Nonisometric Thin Ligament With High Prevalence and Almost Constant Attachment to the Lateral Meniscus: A Systematic Review With Meta-analysis.

PURPOSE: To provide comprehensive information about the anterolateral ligament (ALL) prevalence, morphometry, isometry, insertions, histology, and its relationship with the lateral meniscus (LM). METHODS: The study was performed, according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Eligible cadaveric studies investigating the frequency of the ALL presence, and anatomical features were identified through an online search of the PubMed, Scopus, and Cochrane Central databases from inception to June 2022. Statistical analysis was conducted with the open-source R programming language using the "meta" package. The Higgins I2 statistic was used for quantifying heterogeneity. RESULTS: Thirty-three studies (1,478 cadaveric knees) were included. The ALL had a 79% prevalence. It was attached to the LM periphery in 97% of studies. Most studies reported a femoral insertion of the ALL, just proximal and posterior to the lateral epicondyle. Tibial attachment is constant at the midpoint between Gerdy's tubercle and fibular head. The mean ALL thickness at the joint line was 1.6 [1.2; 2.0] mm. The ALL length was found to significantly change across the knee flexion (P < .01). It was increased from 0° to 60° and decreased after 60° flexion. Seven histological studies demonstrated a typical ligamentous microstructure. CONCLUSION: The ALL is a thin ligament, distinct to the knee capsule, which may be found in 79% of the knees having an almost constant attachment to the LM. The ALL is not isometric. It becomes tense during internal rotation and between 30° and 60° knee flexion. Pooled results should be interpreted with caution due to the high heterogeneity among the included studies. CLINICAL RELEVANCE: This study sheds light on controversial issues and provides comprehensive and accurate information about the essential anatomical knowledge on ALL, which may contribute to optimizing ALL reconstruction surgical techniques and biomechanical settings.

A morphological study on the sphenoid bone ligaments' ossification pattern.

PURPOSE: The sphenoid bone (SB) extracranial ligaments (ECRLs) are the pterygoalar and pterygospinous ligaments (PTAL and PTSL) that are located at the SB lateral pterygoid plate, and inferior to the foramen ovale (FO). Their ossification may affect the mandibular nerve's distribution. The intracranial ligaments' (ICRLs) ossification (the caroticoclinoid ligament-CCLL, the anterior and posterior interclinoid ligaments-AICLL and PICLL) may impede the approaches to the sella. This study highlights the incidence of the ossified ECRLs and ICRLs location, their type (partial, or complete), considering laterality, gender, age, and ligaments' simultaneous presence. METHODS: The sample consisted of 156 Greek adult dried skulls of both genders and variable age. RESULTS: Ossified ligaments were identified in 57.05%, predominantly extracranially (42.31%, P = 0.003). ECRLs were predominantly identified unilaterally (30.13%, P < 0.001). The majority of the ossified ICRLs were predominantly identified in male skulls (31.1%, P = 0.048) and the majority of the ECRLs (52.8%, P = 0.028) were predominantly identified at the age of 60 years and above. The PTAL was the most ossified (32.69%), followed by the CCLL (24.36%), the PTSL (16.03%), the PICLL (6.41%), and the AICLL (4.49%). CONCLUSIONS: Detailed knowledge of the SB morphology and ligaments' ossification extent is essential to improve the technique of the FO percutaneous approach, and sellar approaches, to minimize complications.

The left-sided aortic arch variants: prevalence meta-analysis of imaging studies.

PURPOSE: To estimate the prevalence of the left-sided aortic arch (LSAA) variants, and the effect of possible moderators on variants' detection. METHODS: A systematic online literature search was conducted. The pooled prevalence with 95% confidence intervals was estimated for the typical and atypical branching patterns to compare the overall proportions of different variants. Meta-regression analyses were performed to investigate the effect of the subjects' gender and geographical region, and the multidetector computed tomography (MDCT) scanner's technology on the estimated prevalence. RESULTS: In total, 18,075 cases from 23 imaging studies were included and 33 different LSAA variants were detected. The estimated heterogeneity was statistically significant. Based on the estimated prevalence, approximately 77% of the population is expected to have the typical branching anatomy with sequence brachiocephalic trunk-left common carotid artery-left subclavian artery, and 23% variant branching patterns. Approximately 71%, 23%, 2%, and 0.1% of the atypical populations are expected to have two, four, three, and five emerging branches, respectively. The meta-regression analyses showed that the number of detector rows of the MDCT scanner, and the subjects' geographical region are statistically significant moderators of the estimated prevalence. CONCLUSION: The current findings indicate that the prevalence of the LSAA variant branching anatomy is significantly affected by the subjects' geographical region and the MDCT scanner's technological improvement, with the advanced scanners to facilitate the detection of the aortic arch variants. However, due to the heterogeneity among studies, further research is required.

The efficacy of probiotics as pharmacological treatment of cutaneous wounds: Meta-analysis of animal studies.

The aim of the current meta-analysis of animal studies was to evaluate the efficacy of probiotics as pharmacological treatment of cutaneous wounds. A systematic electronic literature search was conducted and in total six animal studies which undertake twelve experiments met our inclusion criteria. We used the percentage (%) of wound area at the end of the first week after initial wounding to evaluate the efficacy of the probiotic treatment. The heterogeneity was estimated as statistically significant (p<0.0001) and therefore the meta-analysis was performed with the random-effect model. Based on the estimated Hedges' g (Hedges, 1982), the administration of probiotics was associated with acceleration of the wound contraction (g=-2.55; 95%CI=-3.59, -1.50; p<0.0001). The meta-regression analysis showed that the moderator sterile kefir extract has the greater effect on the overall estimated efficacy of probiotic treatment (g=-5.6983; p=0.0442) with bacteria probiotic therapies (70% kefir gel, L. brevis, L. fermentum, L. plantarum, L. reuteri) following (g=-2.3814; p=0.0003). For bacteria dose moderator, the results showed that increase in bacterial dose corresponds to increase of the estimated overall effect size (g=-10.2056; p=0.0053). The linear regression test of funnel plot asymmetry showed absence of publication bias. In conclusion, the results indicate that probiotics administration is an effective pharmacological treatment of cutaneous wounds. However, due to the heterogeneity among studies, further research is required.