Ocular Dyskinesia and Hemifacial Spasm Secondary to Fourth Ventricular Tumor: Report of 4 Cases and Review of the Literature

Experience in treating children with ocular dyskinesia and hemifacial spasm secondary to pontine tumours adjacent to the fourth ventricle and systematic review

OBJECTIVE

To investigate the treatment plan and prognosis of children with ocular dyskinesia and hemifacial spasm secondary to pontine tumours adjacent to the fourth ventricle.

METHODS

In this retrospective study, the clinical information of 10 consecutively collected children with ocular dyskinesia and hemifacial spasm secondary to pontine tumours adjacent to the fourth ventricle was analyzed. All 10 children underwent pontine tumour resection through a trans-cerebellomedullary fissure approach; 4 children underwent preoperative diffusion tensor imaging scans to determine the relationship between the tumour and facial nerve nucleus, and the other 6 children underwent intraoperative deep electroencephalography (EEG) tumour monitoring, in which the tumour electrical discharge activity of the tumour was recorded. A voxel distribution map was established to describe the distribution of the tumour location, and patient prognosis was evaluated through clinical and imaging follow-up.

RESULTS

All 10 children achieved total tumour resection; 9 tumours were pathologically suggested to be ganglioglioma (WHO grade I), and 1 was a hamartoma. The symptoms of the original ocular dyskinesia and hemifacial spasm disappeared immediately after the operation. The children were followed up for 4-75 months, and none of the symptoms recurred; four cases with preoperative diffusion tensor imaging showed that the tumour was close to the facial nerve. Four in six intraoperative electrophysiological monitoring showed that the tumour had electrical discharge behaviour, and the tumour distribution map indicates a high density of tumour presence in the facial nerve nucleus and the nucleus of the abducens nerve.

CONCLUSIONS

In paediatric patients, the facial symptoms are related to the location and abnormal electrical discharge of the tumour. There is no significant correlation between ocular dyskinesia and the location of the tumour. Conventional antiepileptic therapy for this disease is ineffective, and early surgical intervention for total tumour resection can achieve a clinical curative effect.

Microvascular decompression for pediatric-onset hemifacial spasm: case series and literature review

OBJECTIVES

Pediatric hemifacial spasm has been rarely reported in the literature, which contains only 44 cases. Although microvascular decompression (MVD) has been widely regarded as effective therapy for hemifacial spasm, the etiology and surgical treatment of pediatric patients are seldom reported. We report our experience with MVD for pediatric hemifacial spasm patients and review the literature with emphasis on the difference from adults.

METHODS

This retrospective report included 4 pediatric HFS patients, who underwent MVD in our department between January 2014 and May 2021 and then reviewed all the pediatric hemifacial spasm literature on "pubmed" with emphasis on the clinical data.

RESULTS

Our series included 1 boy and 3 girls with an average age of 15.6 ± 3.2 years old; their onset ages were from 7 to 16 years old (11.6 ± 4.3). Three patients achieved immediate excellent outcomes and 1 achieved poor immediately and became good 6 months later. During the operation, all the 4 patients were found compressed by anterior inferior cerebellar artery (AICA). The incidence of pediatric atypical hemifacial spasm patients is 12.5% among the 48 reported cases, which is much higher than adults. Among all the reported 48 cases including ours, the singular artery neurovascular conflictions account for 27/48(56%), the singular vein and combined artery/vein conflictions in 12/48(25%) and the cisternal conflictions in 5/48(10.4%) patients.

CONCLUSIONS

The etiology of pediatric hemifacial spasm is still neurovascular conflict, of which combined artery/vein and singular venous compression patterns have a higher proportion, which might explain higher incidence of pediatric atypical hemifacial spasm and less favorable postoperative outcome. Sufficient arachnoid release, full exploration and decompression along the facial nerve are necessary, which would help to increase the excellent postoperative cure rate among pediatric patients.

A successful treatment of hemifacial spasm due to anterior inferior cerebellar artery aneurysm in adolescent: a case report and literature review

OBJECTIVE

Hemifacial spasm (HFS) is usually caused by compression of the facial nerve at the root exit zone (REZ), and is extremely rare in adolescents and even rarer in aneurysm compression.

CASE REPORT

We describe symptomatic hemifacial spasm caused by a saccular aneurysm of the anterior inferior cerebellar artery (AICA) that was treated by clipping. A 17-year-old adolescent developed left hemifacial spasm that had gradually worsened over a period of 1 year before admission to our department. During the course of MVD (microvascular decompression), saccular aneurysm of AICA was accidentally found to compress the facial nerve. The cause of the facial spasm was considered to be compression of the left facial nerve by the aneurysm. Clipping the aneurysm was performed. The hemifacial spasm disappeared immediately.

CONCLUSION

Our report indicates that HFS caused by saccular aneurysm of AICA can be treated by clipping, and that aneurysms should be considered in the treatment of adolescent HFS, especially those difficult to identify on imaging examination.