Perforating branches from offending arteries in hemifacial spasm: anatomical correlation with vertebrobasilar configuration.
OBJECTIVE: In microvascular decompression for hemifacial spasm, the perforating branches around the facial nerve root exit zone occasionally complicate facial nerve decompression. In this context, the vertebrobasilar configuration was retrospectively correlated with the perforating branches. METHODS: Based on vertebral angiography, magnetic resonance angiography, and three dimensional computed tomographic angiography, 69 patients were divided into three groups, according to the anatomy of the vertebrobasilar system. In patients with the type I configuration, the vertebral artery on the affected side was dominant and had a sigmoidal course. The type II patients had the basilar artery curving mainly towards the affected side. The type III patients showed the basilar artery either running straight or curving toward the unaffected side. The relation of the anatomical configuration of these vessels with the perforating branches around the facial nerve exit zone was investigated. RESULTS: The posterior inferior cerebellar artery in type I patients (n=33) and the anterior inferior cerebellar artery in type II (n=5) and type III (n=31) patients were the most common offending arteries. More than half of the type I patients (n=20) showed no perforating branches around the facial nerve exit zone. However, the type II (n=3) and III patients (n=23) often showed one or more perforating branches around that region. CONCLUSIONS: The configuration of the vertebrobasilar system has a significant correlation with the presence of perforating branches near the site of microvascular decompression. These perforating vessels are often responsible for the difficulty encountered in mobilising the offending artery during the procedure. (+info)
Botulinum toxin treatment of hemifacial spasm and blepharospasm: objective response evaluation.
Twenty seven patients with hemifacial spasm (HFS) and sixteen patients with blepharospasm (BS) having mean Jankovic disability rating scale score of 2.56+0.58 SD and 2.81+0.54 SD, respectively, were treated with botulinum toxin A (BTX-A) injections. The total number of injection sessions were ninety one with relief response in 98.91%. The mean improvement in function scale score was 3.78+0.64 SD and 3.29+1.07 SD respectively, in HFS and BS groups. The clinical benefit induced by botulinum toxin lasted for a mean of 4.46+3.11 SD (range 2 to 13) months in HFS group and 2.66+1.37 SD (range 1 to 6) months, in BS groups. Transient ptosis was seen in 4.39% of total ninety one injection sessions. These findings show that local botulinum toxin treatment provides effective, safe and long lasting relief of spasms. (+info)
Preoperative assessment of trigeminal neuralgia and hemifacial spasm using constructive interference in steady state-three-dimensional Fourier transformation magnetic resonance imaging.
Results of microvascular decompression (MVD) for trigeminal neuralgia (TN) and hemifacial spasm (HFS) may be improved by accurate preoperative assessment of neurovascular relationships at the root entry/exit zone (REZ). Constructive interference in steady state (CISS)-three-dimensional Fourier transformation (3DFT) magnetic resonance (MR) imaging was evaluated for visualizing the neurovascular relationships at the REZ. Fourteen patients with TN and eight patients with HFS underwent MR imaging using CISS-3DFT and 3D fast inflow with steady-state precession (FISP) sequences. Axial images of the cerebellopontine angle (CPA) obtained by the two sequences were reviewed to assess the neurovascular relationships at the REZ of the trigeminal and facial nerves. Eleven patients subsequently underwent MVD. Preoperative MR imaging findings were related to surgical observations and results. CISS MR imaging provided excellent contrast between the cranial nerves, small vessels, and cerebrospinal fluid (CSF) in the CPA. CISS was significantly better than FISP for delineating anatomic detail in the CPA (trigeminal and facial nerves, petrosal vein) and abnormal neurovascular relationships responsible for TN and HFS (vascular contact and deformity at the REZ). Preoperative CISS MR imaging demonstrated precisely the neurovascular relationships at the REZ and identified the offending artery in all seven patients with TN undergoing MVD. CISS MR imaging has high resolution and excellent contrast between cranial nerves, small vessels, and CSF, so can precisely and accurately delineate normal and abnormal neurovascular relationships at the REZ in the CPA, and is a valuable preoperative examination for MVD. (+info)
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. (+info)
Tic convulsif caused by cerebellopontine angle schwannoma.
A case is presented of painful tic convulsif caused by schwannoma in the cerebellopontine angle (CPA), with right trigeminal neuralgia and ipsilateral hemifacial spasm. Magnetic resonance images showed a 4 cm round mass displacing the 4th ventricle and distorting the brain stem in the right CPA. The schwannoma, which compressed the fifth and seventh cranial nerves directly, was subtotally removed by a suboccipital craniectomy. Postoperatively, the patient had a complete relief from the hemifacial spasm and marked improvement from trigeminal neuralgia. The painful tic convulsif in this case was probably produced by the tumor compressing and displacing the anterior cerebellar artery directly. (+info)
Clinical usefulness of magnetic resonance cisternography in patients having hemifacial spasm.
To evaluate the usefulness of MR cisternography fourteen patients that had hemifacial spasm and 20 control patients underwent MR cisternography. All the patients with hemifacial spasm had a confirmed vascular compression after surgery. MR cisternography was performed using a 1.5-tesla superconducting MR magnet in which a 3D (dimensional) heavily T2-weighted turbo spin-echo sequence was used. In 34 randomly selected individuals, we retrospectively determined whether MR cisternography images could be used to evaluate symptoms, and what the benefits of obtaining this image was. The results were correlated with the surgical findings. The sensitivity was 100% and the specificity was 94% in all patients having a hemifacial spasm. The offending vessels were the anterior inferior cerebellar artery (AICA) in six patients cases, the posterior inferior cerebellar artery (PICA) in six, both the vertebral artery and PICA in one, and the vertebral artery in one. All the images showed good resolution and contrast, and also showed the exact correlation between the facial nerve and intracranial vessels in the multiplaner image. The findings of neurovascular compression were well correlated with the surgical findings. We believe that high-resolution 3D MR cisternography is a very useful method for evaluating the neurovascular compression in patients that have hemifacial spasm. (+info)
Cerebellopontine angle epidermoid tumor presenting with 'tic convulsif' and tinnitus--case report.
A 22-year-old female presented with a cerebellopontine angle epidermoid tumor manifesting as a rare combination of hemifacial spasm, trigeminal neuralgia, and tinnitus. Magnetic resonance imaging demonstrated the tumor distorting the brainstem and the fourth ventricle. The tumor was almost completely resected and the seventh-eighth cranial nerve complex was decompressed by mobilizing the anterior inferior cerebellar artery loop. No arterial loop was related to the trigeminal nerve. The patient was completely relieved of the "tic convulsif" and tinnitus after the surgery. The inflammatory nature of epidermoid tumor may be involved in the etiology of the syndrome. Microvascular decompression may be needed in addition to tumor removal in such cases. (+info)
Snare technique of vascular transposition for microvascular decompression--technical note.
Recurrence of trigeminal neuralgia (TN) or hemifacial spasm (HFS) after microvascular decompression (MVD) is not rare. The prosthesis material eventually adheres to the neurovascular structures and again transmits arterial pulsation to the nerve. A snare ligature technique using a Gore-Tex tape can be used for the transposition of the offending artery. No prosthesis is necessary once the transposition is complete. This technique requires introduction of either Gore-Tex tape or thread around the artery and suture over the petrous dura, so an adequate working space as if operating in a shallow basin is essential. Therefore, the osteoplastic craniotomy is a little larger than usual with the scalp flap entirely reflected using a semicircular skin incision. The Gore-Tex tape can be directly snared around the artery and sutured over the petrous dura. If this procedure is difficult, a thread can be attached to both ends of the Gore-Tex tape to pass the tape around the vessel. Seven patients with TN and 13 patients with HFS have undergone this surgery. Although the follow-up period is not yet long enough, there has been no case of recurrence. The present technique for MVD can provide complete and permanent transposition of the offending artery. (+info)