Conformation of the Posterior Fossa of the Skull: A Predisposing Factor in Patients with Hemifacial Spasm

Corresponding author: Ha-Young Choi Department of Neurosurgery, Chonbuk National University Hospital, Chonbuk National University, 20, Geonjiro Deokjin-gu, Jeonju 54907, Republic of Korea Tel: +82-63-250-1870 Fax: +82-63-277-3273 E-mail: cbnu23450@gmail.com Objective: Hemifacial spasm (HFS) can be caused by vascular compression of the facial nerve at the root entry zone in the brain stem. The study aims to analyze the length and volume of the posterior cranial fossa (PCF) and the angle of skull flatness to evaluate any possible contribution of morphological characteristics to the development of neurovascular compression leading to HFS. Methods: We enrolled 30 patients with HFS and matched them by age and sex to controls. Three-dimensional volumetric analyses of the PCF were performed using magnetic resonance imaging. We measured the angle and approximate volume of the PCF using the ellipsoid method. Results: The mean volume of the PCF in patients with HFS was significantly lower (220.2±24.9 vs. 243.1±31.2; p=0.003) than in controls. In addition, the mean angle of the PCF of patients with HFS was smaller than that of controls (100.7±6.0 vs. 106.5±7.0; p=0.001). Several clinical factors were investigated, and there were significant associations between PCF volume and hypertension. Hypertension is more common in the HFS patient group than in the control group (18/30 [60.0%] vs. 10/30 [33.3 %]; p=0.038). Conclusion: Our results suggest that patients with HFS can be characterized by flatness of the skull and small volume of the PCF. These structural differences may play a role in neurovascular compression in patients with HFS.

• Publication year

  2020

• Venue

  Unknown venue

• Publication date

  2020-10-28

• Fields of study

  Medicine

• Identifiers
  DOI 10.21129/nerve.2020.6.2.31
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar

• No claims are published for this paper.

• No concepts are published for this paper.

• Clinical analysis of microvascular decompression in patients with hemifacial spasm: a retrospective study.

  2020cited by this paper
• The conflicting vessels in hemifacial spasm: Literature review and anatomical-surgical implications.

  2018cited by this paper
• Flat Posterior Cranial Fossa Affects Outcomes of Microvascular Decompression for Trigeminal Neuralgia.

  2017cited by this paper
• Flatness of the infratentorial space associated with hemifacial spasm

  2016cited by this paper
• Structural changes in the CNS of patients with hemifacial spasm.

  2015cited by this paper
• Quantitative Study of Posterior Fossa Crowdedness in Hemifacial Spasm.

  2015cited by this paper
• Small volume of the posterior cranial fossa and arterial hypertension are risk factors of hemifacial spasm.

  2014cited by this paper
• A clinical analysis on microvascular decompression surgery in a series of 3000 cases.

  2012cited by this paper
• Hemifacial spasm: conservative and surgical treatment options.

  2012cited by this paper
• Prevalence of hemifacial spasm in Oslo, Norway

  2004cited by this paper
• Primary hemifacial spasm and arterial hypertension: A multicenter case–control study

  2000cited by this paper
• Determination of race and sex of the human skull by discriminant function analysis of linear and angular dimensions

  1989cited by this paper
• Etiology and definitive microsurgical treatment of hemifacial spasm. Operative techniques and results in 47 patients.

  1977cited by this paper

• [Familial hemifacial spasm].

  2025cites this paper