Hemifacial spasm due to tumor, aneurysm, or arteriovenous malformation.

The authors report eight cases of so-called symptomatic hemifacial spasm. They had gross pathological lesions such as a tumor (one epidermoid, one neurinoma, and two meningiomas), vascular malformation (one medullary venous malformation and two arteriovenous malformations), and aneurysm. In all four cases with a tumor, no artery compressed the facial nerve at the root exit zone. In three of the four cases, the hemifacial spasm disappeared after removal of the tumor in contact with the facial nerve. Compression or encasement of the facial nerve by the tumor was the pathogenesis of the hemifacial spasm in these three cases. The remaining case with tumor (tentorial meningioma) did not have a mass or vessel that directly compressed the facial nerve at the root exit zone. However, the hemifacial spasm disappeared after the removal of the tumor. In a case with a medullary venous malformation with arterial component, an engorged draining vein compressed the root exit zone of the facial nerve. In the remaining three vascular cases--two cases of arteriovenous malformation and a case of saccular aneurysm--enlarged feeding arteries and an aneurysm directly compressed the root exit zone of the facial nerve. Not only arterial or venous but also mass compression can cause hemifacial spasm in some symptomatic cases. Surgical decompression of the facial nerve from the causative organic lesion is the primary choice of treatment.     

Hemifacial spasm due to cerebellopontine angle meningiomas--two case reports

A 54-year-old female and a 49-year-old female presented with complaints of hemifacial spasm. Both patients underwent surgery to remove cerebellopontine angle meningiomas. In one case, no vascular compression was observed at the root exit zone. The tumor was removed subtotally leaving residual tumor adhered to the lower cranial nerves. The hemifacial spasm disappeared immediately after the operation. The residual tumor was treated using gamma knife radiosurgery. In the other case, the root exit zone of the facial nerve was compressed by both the tumor and anterior inferior cerebellar artery and the tumor was removed totally. Postoperatively, the hemifacial spasm disappeared, but the patient suffered facial nerve paresis and deafness that was probably due to intraoperative manipulation. However, the facial nerve paresis gradually improved. Cerebellopontine angle meningioma with hemifacial spasm must be treated by surgical resection limited to preserve cranial nerve function. Subtotal removal with subsequent radiosurgery to treat the remaining tumor tissue is one option for the treatment of cerebellopontine angle meningioma.     

CP angle meningioma presenting as hemifacial spasm

An interesting case of CP angle meningioma presenting with hemifacial spasm is reported. The patient was a 64-year-old woman with left hemifacial spasm of 18 years' duration which was the initial and the only symptom she had had for ten years until other signs and symptoms including tinnitus and hearing decrease on the left side, vertigo and left cerebellar disturbance occurred. Preoperative CT films showed an enhancing mass at the left CP angle. Operation was performed and the diagnosis of meningioma originating at the rostral edge of the jugular foramen was made. The tumor was extending from the lower cranial nerves up to the Vth nerve burring the VIIth, VIIIth, IXth, Xth, XIIth cranial nerves and vertebral artery within it and compressing the root exit zone of the VIIth nerve. It was totally removed by microsurgical techniques. Postoperative follow-up during eight months disclosed complete disappearance of hemifacial spasm. Residual neurological deficits were left hearing loss, mild facial weakness due to previous nerve blocks on the left side and slight hoarseness. But she was doing well as a housewife. So far, the authors have experienced with 1310 cases of microvascular decompression for hemifacial spasm and 730 cases for tic douloureux. There were only 4 cases (0.3%) in which a CP angle tumor was found in hemifacial spasm series, while in tic douloureux series as many as 79 tumor cases (10.8%) were found. A review of the literature revealed that hemifacial spasm due to CP angle meningioma was very rare, particularly as an initial symptom as in our case.(ABSTRACT TRUNCATED AT 250 WORDS)     

Arteries in contact with the cisternal portion of the facial nerve in autopsy cases: microsurgical anatomy for neurovascular decompression surgery of hemifacial spasm

The cisternal portion of the facial nerve and its contact arteries were examined anatomically in relation to neurovascular decompression surgery to treat hemifacial spasm. Thirty-five sides of brains from 20 autopsied adult patients were examined under a surgical microscope (x 5-x 25). One attaching point was found on 10 facial nerves, two points on 20 nerves, and three points on four nerves. More than two thirds of the facial nerves were attached at two points: the root exit zone and the distal cisternal portion. In a case of distal attachment, the contact artery formed an arterial-nerve complex with the distal portions of the facial and acoustic nerves. The arterial attachment at the root exit zone was evident on 24 of the 35 facial nerves (69%), and most of the contact arteries were the anterior inferior cerebellar artery and its branches. In five nerves, the root exit zone was attached at two points to arteries. The anatomy of autopsied brains without hemifacial spasm is not identical to that of actual clinical cases of hemifacial spasm; nevertheless, the results do aid in intraoperative anatomical orientations.     

Surgical treatment of hemifacial spasm associated with tortuous vertebrobasilar system (author's transl)]

Surgical treatment of hemifacial spasm associated with tortuous vertebrobasilar system was reported. A patient was 63-year-old female, who first experienced mild and intermittent muscle twitching around her left eye twenty years prior to admission. Five years later, the twitching extended to all the facial muscles on the left side. She was treated with facial nerve block, which resulted in facial palsy for about one year. Because of recurrence of the hemifacial spasm, she was admitted to the Neurosurgical Department of Bokuto Municipal Hospital on October 12, 1977. Neurological examination revealed no abnormalities except for left hemifacial spasm with slight muscular weakness. Electromyogram showed severe twitching and synkinesis of all the muscles of facial expression. Vertebral angiogram on the left side disclosed pronounced elongation of the vertebral and basilar arteries, which extended into the left cerebellopontine angle. Compression of the facial nerve root exit zone at the brainstem by the vertebral artery was considered to be the cause of the hemifacial spasm. Suboccipital craniectomy was carried out on November 29, 1977. The vertebral artery extended into the cerebellopontine angle, and adhered to the facial nerve. After mobilization of the vertebral artery from the facial nerve, a small prosthesis of non-absorbable spongy material (Teflon felt) was interposed between the vertebral artery and brainstem. Postoperatively, the hemifacial spasm disappeared, but the facial palsy, which had been observed preoperatively probably due to previous facial nerve block and long-standing hemifacial spasm, remained. The function of the acoustic nerve was preserved. Recently vascular compression of the facial nerve root exit zone has been reported as a major cause of hemifacial spasm, but such abnormal vessels are rarely demonstrated angiographically.     

Cerebellopontine angle tumors causing hemifacial spasm: types, incidence, and mechanism in nine reported cases and literature review

Objective  

Although hemifacial spasm is usually caused by vascular compression around the root exit zone of the facial nerve, it is sometimes brought on by a cerebellopontine angle tumor. We reviewed and analyzed data from past experience with hemifacial spasm induced by cerebellopontine angle tumors.     

Hemifacial spasm associated with a cerebellopontine angle arachnoid cyst in a young adult.

There are no reported cases of hemifacial spasm associated with an arachnoid cyst in the literature. We report the first case of hemifacial spasm with an ipsilateral cerebellopontine angle arachnoid cyst in a 25-year-old man. The patient underwent evacuation of the arachnoid cyst by a partial membranectomy without any beneficial effect, and finally got rid of the hemifacial spasm by reexploration and microvascular decompression of the facial nerve. The operative findings and results revealed that the cyst produced deviation of the ipsilateral posterior inferior cerebellar artery, which was secondarily in contact with the root exit zone of the facial nerve.     

Hemifacial spasm associated with an ependymal cyst in the cerebellopontine angle. Case report

No previous case of hemifacial spasm associated with an ependymal cyst has been reported in the literature. In this article the authors report the first case in which hemifacial spasm accompanied an ipsilateral cerebellopontine angle ependymal cyst in a 27-year-old woman. Cyst fenestration and arterial decompression of the facial nerve at the root exit zone resulted in complete resolution of the patient's symptoms. A histopathological study including immunohistochemical methods identified an ependymal cyst.     

Hemifacial spasm due to vascular compression of the distal portion of root exit zone of the facial nerve: report of two cases

It has been generally assumed that only vascular contact at the root exit zone (REZ) of the facial nerve can cause hemifacial spasm. We treated two cases of hemifacial spasm in which compression of the distal site of the REZ of the facial nerve produced symptoms. The microvascular decompression for the patients showed excellent results. Extreme care must be taken not to stretch the internal auditory artery during surgical manipulation. The ABR monitoring is useful to prevent the postoperative hearing loss. It must be kept in mind that the compression of distal portions of the facial nerve may be responsible for hemifacial spasm in cases in which neurovascular compression at the REZ is not confirmed intraoperatively.     

Resolution of hemifacial spasm after posterior fossa exploration without vascular decompression

A 57-year-old woman who had hemifacial spasm on the left side for 5 years underwent exploration of the cerebellopontine angle region for the purpose of microvascular decompression. At operation, however, no artery, vein, or other abnormality was noted at the facial nerve root exit zone. Consequently, the exploration was completed without additional manipulation or the placement of a protective barrier, but the patient awoke from the operation completely free of the spasm. The cause of the hemifacial spasm in this patient could not be explained by the currently predominating vascular compression theory.     

Microneurovascular decompression in patients with hemifacial spasm caused by vascular compression of facial nerve at cisternal portion

Background  

Hemifacial spasm is commonly caused by arterial compression of the facial nerve. Although vascular compression usually occurs at the facial nerve exit zone, in some cases, the facial nerve is compressed more distally. We analyzed the clinical outcome of microneurovascular decompression in patients with hemifacial spasm caused by either distal or proximal compression.     

Hemifacial spasm caused by a tortuous recurrent perforating artery: A case report

IntroductionWhen the culprit vessel in hemifacial spasm (HFS) is hard to determine, this is a challenge in microvascular decompression (MVD) surgery. In such a situation, small arteries such as perforators to the brainstem might be suspected. But small arteries are omnipresent near the facial nerve root exit/entry zone (fREZ). How to decide whether a given small artery is responsible for HFS is unclear.MethodWe report a case with a previously unreported form of neurovascular impingement, in which the culprit was found to be the recurrent perforating artery (RPA) from the anterior inferior cerebellar artery (AICA). An aberrant anatomic configuration of the RPA was found intraoperatively, which we thought was responsible for generating focal pressure on the facial nerve.Case reportA 62-year-old woman presented with a 1-year history of paroxysmal but increasingly frequent twitching in her right face. MRI showed tortuosity of the vertebral artery and apparently marked neurovascular impingement on the asymptomatic left side, while only the right AICA could be implicated as the possible culprit. Hemifacial spasm was diagnosed based on the typical clinical manifestation, and MVD was performed. The pre-meatal segment of the AICA was found not to be impinging the facial nerve at any susceptible portion near the fREZ: root exit point, attached segment, or root detachment point. The real culprit was in fact the RPA. This occult culprit vessel was tortuous, forming a coil-shaped twist which was interposed between the facial nerve and the intermediate nerve near the root detachment point. Focal pressure atrophy of the nerve was clearly observed at the compressing site. The patient achieved total spasm relief immediately after surgery, and remained spasm-free at 1-year follow-up, without any postoperative complications.ConclusionMVD is the only curative treatment for hemifacial spasm, but with a failure rate of around 10%. Mistaking the real culprit has been reported to be the most likely reason for surgical failure. Therefore, intraoperative identification of atypical occult forms of vascular compression is of importance to improve surgical outcome. In the present case, the RPA formed a coil-shaped twist, which inflicted focal vascular compression causing hemifacial spasm. We recommend careful inspection of the recurrent perforating artery during MVD for HFS, and decompressing any such neurovascular impingement.     

Monitoring of the lateral spread response in the endovascular treatment of a hemifacial spasm caused by an unruptured vertebral artery aneurysm. Case report

The lateral spread response (LSR) is used in the electrophysiological diagnosis of a hemifacial spasm or for monitoring during microvascular decompression. The authors used LSRs for intraoperative monitoring during endovascular surgery in a rare case of vertebral artery (VA) aneurysm that caused intractable hemifacial spasm. A 49-year-old woman presented with a right hemifacial spasm that had persisted for 9 months. No other clinical symptom was observed. Vertebral artery angiography revealed a saccular aneurysm of the right VA. Magnetic resonance (MR) imaging demonstrated that the aneurysm was compressing the root exit zone of the right facial nerve. Endovascular treatment of the VA aneurysm was performed while monitoring the patient's LSRs. During occlusion of the VA at sites distal and proximal to the aneurysm, the LSRs temporarily disappeared and then reappeared with a higher amplitude than those measured preceding their disappearance. The hemifacial spasm alleviated gradually and disappeared completely 6 months after treatment. The LSRs changed in parallel with the improvement in the patient's hemifacial spasms and eventually disappeared. No recurrence of symptoms has been noticed as of 18 months postoperatively. This is the first report of the use of LSR monitoring during endovascular surgery for an intracranial aneurysm that causes hemifacial spasm. Intraoperative and postoperative changes in the LSRs provided useful information regarding the pathophysiology of hemifacial spasm.     

Surgical treatment of hemifacial spasm with zone-4 offending vessel

Background

Increasing evidence shows that vascular compression on any of the four zones of facial nerve may cause hemifacial spasms. Vascular compression on zone 4 (the cisternal portion) of the nerve is quite common, but only a very small percentage of such compression will elicit hemifacial spasm, because zone 4 is less susceptible than zone 3 (the root exit zone). Therefore, it seems difficult for the neurosurgeons to distinguish the real culprit vessels in zone 4. Here, our experience in treating vascular compression located in zone 4 of the facial nerve is reported.

Methods

Twelve patients of HFS due to compression of zone 4 were treated with microvascular decompression (MVD) surgery with the aid of combined monitoring of abnormal muscle response (AMR) and Z-L response (ZLR).

Results

All of the 12 patients had a zone 4 compression. In addition, there were vascular compressions on zone 3 (the root exit zone) and/or zone 2 (the attached segment) in six cases. AMR was absent in two cases, unstable in one case, and persisted after vascular decompression in another one case. ZLR was stable before decompression of zone 4 and disappeared after decompression in all cases. After MVD surgery, 11 patients were cured and one patient achieved good resolution of spasm. One patient had postoperative transient tinnitus.

Conclusions

The neurosurgeon should not ignore vascular compression at zone 4, especially when compressions at zones 2 and 3 co-exist. With the aid of AMR and ZLR, we are able to judge whether offending vessels exist at zone 4.     

Hemifacial Spasm Due to a Large Distant Ipsilateral Posterior Fossa Meningioma

A rare case of hemifacial spasm due to an ipsilateral foramen magnum/clival meningioma is described. Magnetic resonance imaging demonstrated that the tumor was located distant to the cranial nerve VII/VIII complex. Resolution of the ipsilateral hemifacial spasm was noted after complete resection of the tumor. The mechanism of hemifacial spasm was likely due to displacement and distortion of the brain stem from the lesion distant to the cranial nerve VII/VIII complex. In our review of the literature this is the first reported case of an ipsilateral posterior fossa meningioma causing hemifacial spasm from indirect mass effect.     

Hemifacial spasm due to a large distant ipsilateral posterior fossa meningioma

A rare case of hemifacial spasm due to an ipsilateral foramen magnum/clival meningioma is described. Magnetic resonance imaging demonstrated that the tumor was located distant to the cranial nerve VII/VIII complex. Resolution of the ipsilateral hemifacial spasm was noted after complete resection of the tumor. The mechanism of hemifacial spasm was likely due to displacement and distortion of the brain stem from the lesion distant to the cranial nerve VII/VIII complex. In our review of the literature this is the first reported case of an ipsilateral posterior fossa meningioma causing hemifacial spasm from indirect mass effect.     

Hemifacial spasm caused by CP angle AVM associated with ruptured aneurysm in the feeding artery--case report.

A 66-year-old male presented with clinical features of hemifacial spasm. Cerebral angiograms disclosed an arteriovenous malformation (AVM) in the cerebellopontine angle. The hemifacial spasm was caused by a dilated feeding artery of the AVM compressing the facial nerve at the root exit zone. Surgery was not initially performed because of his age and absence of AVM rupture. However, the AVM was associated with a small aneurysm in the feeding artery, which rapidly grew during 20 days after discharge and ruptured causing subarachnoid hemorrhage. The aneurysm was clipped and the feeding artery of the AVM partially obliterated. Careful angiographic examination for associated aneurysms and consequent surgical obliteration to prevent hemorrhage are suggested in cases of AVM.     

Fusiform aneurysm of the vertebral artery presenting with hemifacial spasm treated by microvascular decompression

Summary We report a rare case of symptomatic hemifacial spasm caused by a fusiform vertebral artery aneurysm. A 59-year-old woman presented with left hemifacial spasm of 18 months duration. Magnetic resonance imaging showed an enlarged a fusiform aneurysm of the left vertebral artery which compressed the seventh cranial nerve at its exit from the caudal pons. Microvascular decompression of the facial nerve with moving of the aneurysm resulted in complete relief of the hemifacial spasm. No enlargement of the aneurysm was shown on follow-up for a period of 6 years.     

Hemifacial spasm due to cerebellopontine angle epidermoid tumor--case report.

The authors report a case of cerebellopontine angle epidermoid presenting as typical hemifacial spasm. A 33-year-old male had experienced intermittent right hemifacial spasm for 2 years. Cranial nerve examination was otherwise normal, including auditory and trigeminal nerve functions. Metrizamide computed tomographic cisternography and magnetic resonance imaging demonstrated a characteristic epidermoid tumor. The tumor was totally removed. Postoperatively, no facial spasm or other facial nerve dysfunction was noted.