Disappearance of Hemifacial Spasm After Ventriculoperitoneal Shunting in a Patient With Achondroplasia-Case Report-

Correlation between bony structures of the posterior cranial fossa and the occurrence of hemifacial spasm

Objective

To quantitatively study the measurement data related to the bony posterior cranial fossa and explore the correlation between bony posterior cranial fossa morphology and the occurrence of hemifacial spasm.

Methods

A total of 50 patients with hemifacial spasm who attended the Department of Neurosurgery of China-Japan Friendship Hospital from October 2021 to February 2022 were included, and 60 patients with minor head trauma excluding skull fracture and intracranial abnormalities were included as controls. Cranial multilayer spiral CTs (MSCTs) were performed in both groups, and multiplanar reconstruction (MPR) was used as a postprocessing method to measure data related to the posterior cranial fossa in both groups.

Results

Compared with the control group, the anteroposterior diameter (labeled AB) and the height (labeled BE) of the bony posterior cranial fossa, the anteroposterior diameter of the foramen magnum (labeled BC), the length of the clivus (labeled AB), and the length of the posterior occipital (labeled CD) in the HFS group were all reduced, and the differences were statistically significant. BE is positively correlated with AB and CD, with a stronger correlation observed between BE and AB (r = 0.487, p < 0.01). AB is negatively correlated with AD (r = -0.473, p < 0.01). The remaining correlations between the data were not statistically significant. There was no overlap in the 95% confidence interval for any of the measurements between the hemifacial spasm group and the control group.

Conclusion

There is a correlation between the posterior cranial fossa and hemifacial spasm.

Two-dimensional structure analysis of hemifacial spasms and surgical outcomes of microvascular decompression

BACKGROUND

Although studies have indicated that the small posterior fossa plays a role in hemifacial spasm (HFS), few studies have denoted the correlations between local measurements of the cerebellopontine angle and the incidence of HFS and surgical outcomes.

METHODS

We retrospectively analyzed the demographic and clinical data of HSF patients who underwent microvascular decompression at our institution. Healthy controls were recruited. The divergent prognosis of HFS was defined as an ordinal variable. A multivariable ordinal regression model was generated to estimate the relationship between the variables and outcomes of HFS.

RESULTS

Between 2013 and 2018, 180 patients who were enrolled in our study met the inclusion criteria. Compared with the control group (n = 94), HFS patients had a smaller internal acousticmeatus-brainstem distance (P < 0.001) on the unaffected side and a larger facial nerve-brainstem angle (P < 0.001). The regression analysis demonstrated that subgroups with more severe facial nerve compression (mild vs severe, OR = 0.269, P = 0.018; moderate vs severe, OR = 0.215, P < 0.001) and a thinner brainstem (OR = 2.368, P = 0.014) were more likely to experience better short-term outcomes, while subgroups with a thinner brainstem (OR = 5.583, P = 0.007) were more likely to experience better long-term outcomes.

DISCUSSION

Structural changes occurring in patients are risk factors for HFS. The patient's local neurovascular structure and brainstem volume are factors that significantly influence short-term and long-term surgical outcomes.

Clinical Practice Guidelines for Achondroplasia

Achondroplasia (ACH) is a skeletal dysplasia that presents with limb shortening, short stature, and characteristic facial configuration. ACH is caused by mutations of the FGFR3 gene, leading to constantly activated FGFR3 and activation of its downstream intracellular signaling pathway. This results in the suppression of chondrocyte differentiation and proliferation, which in turn impairs endochondral ossification and causes short-limb short stature. ACH also causes characteristic clinical symptoms, including foramen magnum narrowing, ventricular enlargement, sleep apnea, upper airway stenosis, otitis media, a narrow thorax, spinal canal stenosis, spinal kyphosis, and deformities of the lower extremities. Although outside Japan, papers on health supervision are available, they are based on reports and questionnaire survey results. Considering the scarcity of high levels of evidence and clinical guidelines for patients with ACH, clinical practical guidelines have been developed to assist both healthcare professionals and patients in making appropriate decisions in specific clinical situations. Eleven clinical questions were established and a systematic literature search was conducted using PubMed/MEDLINE. Evidence-based recommendations were developed, and the guidelines describe the recommendations related to the clinical management of ACH. We anticipate that these clinical practice guidelines for ACH will be useful for healthcare professionals and patients alike.

Hemifacial Spasm in Mucopolysaccharidosis Type VI (Maroteaux-Lamy Syndrome)

Background

Hemifacial spasms are involuntary contractions of the muscles of one side of the face.

Case Report

Here, we report a 5-year-old female patient with a significant past medical history, including mucopolysaccharidosis type VI, who also presented with hemifacial spasms. Further investigations showed narrowing of skull foramina and hydrocephalus, but no compression of the facial nerve. Carbamazepine was given to the patient, which caused cessation of the spasms.

Discussion

Currently, there is no literature discussing the relationship between hemifacial spasms and mucopolysaccharidosis type VI; we have proposed that mucopolysaccharide deposits or dural thickening may contribute to nerve irritation.

Does a small posterior fossa increase nerve vascular conflict in trigeminal neuralgia?

BACKGROUND

Magnetic resonance imaging (MRI) can be helpful in visualizing neurovascular conflict (NVC) of the trigeminal nerve in patients with trigeminal neuralgia (TN), but the relationship between these two events is controversial.

PURPOSE

To investigate whether posterior fossa volume is a predisposing factor for NVC in TN.

MATERIAL AND METHODS

We conducted a case-control study of clinically diagnosed idiopathic TN of 30 patients aged 30-79 years and 30 age- and sex-matched controls. We compared the volume of the posterior fossa and subarachnoid space using fast-imaging employing steady-state acquisition MRI and the iPlan® programme of BrainLab.

RESULTS

The posterior fossa volumes in controls and patients with TN were 168.97 cm(3) and 167.63 cm(3), respectively. A small pontomesencephalic cistern volume was more frequent in TN. However, neither the cisternal nor parenchymal portions of the posterior fossa were different between patients with TN and controls, and no significant volume difference was observed in this study.

CONCLUSION

Although the hypothesis that small posterior fossa volume influences TN was feasible, we did not find any volumetric differences (including the cisternal and parenchymal volumes).However, small pontomesencephalic cistern volumes were more frequent in patients with TN.