Infraorbital canal variants and its clinical and surgical implications. A systematic review

BACKGROUND

Recent literature highlights anomalous cranial nerves in the sinonasal region, notably in the sphenoid and maxillary sinuses, linked to anatomical factors. However, data on the suspended infraorbital canal (IOC) variant is scarce in cross-sectional imaging. Anatomical variations in the sphenoid sinuses, including optic, maxillary, and vidian nerves, raise interest among specialists involved in advanced sinonasal procedures. The infraorbital nerve's (ION) course along the orbital floor and its abnormal positioning within the orbital and maxillary sinus region pose risks of iatrogenic complications. A comprehensive radiological assessment is crucial before sinonasal surgeries. Cone-beam computed tomography (CBCT) is preferred for its spatial resolution and reduced radiation exposure.

OBJECTIVE

The aim of this study was to describe the prevalence of anatomical variants of the infraorbital canal (IOC) and report its association with clinical condition or surgical implication.

METHODS

We searched Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception up to June 2023. Two authors independently performed the search, study selection, data extraction, and assessed the methodological quality with assurance tool for anatomical studies (AQUA). Finally, the pooled prevalence was estimated using a random effects model.

RESULTS

Preliminary results show that three types are prevalent, type 1: the IOC does not bulge into the maxillary sinus (MS); therefore, the infraorbital foramen through the anterior wall of MS could be used for identification of the ION. Type 2: the IOC divided the orbital floor into medial and lateral aspects. Type 3: the IOC hangs in the MS and the entire orbital floor lying above the IOC. From which the clinical implications where mainly surgical, in type 1 the infraorbital foramen through the anterior wall of MS could be used for identification of the ION, while in type 2, since the lateral orbital floor could not be directly accessed an inferiorly transposition of ION is helpful to expose the lateral orbital wall directly with a 0 scope; or using angled endoscopes and instruments, however, the authors opinion is that direct exposure potentially facilitates the visualization and management in complex situations such as residual or recurrent mass, foreign body, and fracture located at the lateral aspect of the canal. Lastly, in type 3, the ION it's easily exposed with a 0° scope.

CONCLUSIONS

This systematic review identified four IOC variants: Type 1, within or below the MS roof; Type 2, partially protruding into the sinus; Type 3, fully protruding into the sinus or suspended from the roof; and Type 4, in the orbital floor. Clinical recommendations aim to prevent nerve injuries and enhance preoperative assessments. However, the lack of consistent statistical methods limits robust associations between IOC variants and clinical outcomes. Data heterogeneity and the absence of standardized reporting impede meta-analysis. Future research should prioritize detailed reporting, objective measurements, and statistical approaches for a comprehensive understanding of IOC variants and their clinical implications. Open Science Framework (OSF): https://doi.org/10.17605/OSF.IO/UGYFZ .

Systematic review and meta-analysis of right subclavian artery variants and their correlation with cervical-thoracic clinical conditions

BACKGROUND

A high incidence of anatomical variations in the origin of the branches of the aortic arch has been reported, Nowadays, this variation is considered the most frequent in the aortic arch, its prevalence being estimated between 0.5% and 2.5% of the population. To understand its origin, knowledge of embryonic development is necessary.

METHODS

We searched the MEDLINE, Scopus, Web of Science, Google Scholar, Cumulative Index to Nursing and Allied Health Literature, and Latin-American literature and caribean of health sciences databases with dates ranging from their inception to June 2023. Study selection, data extraction, and methodological quality were assessed with the guaranteed tool for anatomical studies (Anatomical Quality Assurance). Finally, the pooled prevalence was estimated using a random effects model.

RESULTS

Thirty-nine studies were found that met the eligibility criteria. Twenty studies with a total of 41,178 subjects were included in the analysis. The overall prevalence of an ARSA variant was 1% (95% confidence interval = 1%-2%), the clinical findings found are that if ARSA is symptomatic it could produce changes in the hemodynamic function of the thoracocervical region in addition to other associated symptomatic complications in surrounding structures.

CONCLUSIONS

ARSA can cause several types of alterations in the cervical or thoracic region, resulting in various clinical complications, such as lusory dysphagia. Hence, knowing this variant is extremely important for surgeons, especially those who treat the cervico-thoracic region. The low prevalence of ARSA means that many professionals are completely unaware of its existence and possible course and origin. Therefore, this study provides detailed knowledge of ARSA so that professionals can make better diagnoses and treatment of ARSA.

Effectiveness of alpha-lipoic acid in patients with neuropathic pain associated with type I and type II diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

This systematic review explores the most current evidence regarding the mechanisms of neuropathic pain in patients with different types of diabetes and how this pain affects different functional and structural components of the neuroanatomical pain pathways. The review also seeks to provide guidelines for the best approach and treatment for patients experiencing this type of pain. The objective is to determine the effectiveness of alpha-lipoic acid (ALA) in improving functional and symptomatic outcomes in patients with diabetes mellitus type I and type II.

OBJECTIVE

To determine the effectiveness of alpha-lipoic acid (ALA) in improving functional and symptomatic outcomes in patients with diabetes mellitus type I and type II.

METHODS

We systematically search MEDLINE (via PubMed), EMBASE, SCOPUS, the Cochrane Central Register of Controlled Trials, the Cumulative Index to Nursing and Allied Health Literature, and Web of Science databases.

RESULTS

The findings of this review show that different forms of ALA do not present statistically significant changes for any of the scales included, including total symptom score (standardized mean difference [SMD] = -3.59, confidence interval [CI] = -4.16 to -3.02, and P < .00001), neuropathy impairment score (SMD = -1.42, CI = -3.68 to 0.84, and P = .22), and neuropathy symptom checklist (SMD = -0.09, CI = -0.15 to -0.02, and P = .01).

CONCLUSION

In comparison to the use of a placebo, the findings suggest that ALA does not exhibit significant differences in terms of pain reduction and different functional scales. Moreover, no specific dosages are identified to support the use of ALA for the reduction of neuropathic pain.

Prevalence of the Bifid Mandibular Condyle and Its Relationship with Pathologies of the Temporomandibular Joint: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this study was to describe the prevalence of anatomical variants in the bifid mandibular condyle (BMC) and report its association with temporomandibular joint (TMJ) pathology.

METHODS

We searched the Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception up to September 2023. Two authors independently performed the search, study selection, and data extraction, and they also assessed the methodological quality with an assurance tool for anatomical studies (AQUA). Finally, the pooled prevalence was estimated using a random effects model.

RESULTS

A total of 50 studies met the eligibility criteria. Twenty studies, with a total of 88,625 subjects, were included in the meta-analysis. The overall prevalence of the bifid mandibular condyle (BMC) variant was 1% (95% CI = 1% to 2%).

CONCLUSIONS

The correlation between the BMC and TMJ pathologies has a relatively low prevalence in studies that present a considerable number of subjects. From a clinical point of view, a direct association cannot be made between the presence of the BMC and TMJ pathologies or symptoms.

Incidence and Clinical Implications of Anatomical Variations in the Pancreas and Its Ductal System: A Systematic Review and Meta-Analysis

OBJECTIVE

This systematic review analyzes the anatomical variants in the pancreas and its ductal system to report on their association with pancreatic pathologies.

METHODS

We conducted a search of the MEDLINE, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception to July 2023. The methodological quality was assessed with the Anatomical Quality Assessment (AQUA) tool. Finally, the pooled prevalence was estimated using a random effects model.

RESULTS

55 studies were found that met the eligibility criteria. The overall prevalence of pancreas divisum (PD) was 18% (95% CI = 15-21%). The prevalence of PD associated with pancreatitis was 30% (95% CI = 1-61%).

CONCLUSIONS

An anatomical variant of the pancreas such as PD may be the cause of bile duct obstruction, resulting in various clinical complications, such as pancreatitis. Hence, knowing this variant is extremely important for surgeons, especially for those who treat the gastroduodenal region.