Outcome of pallidal deep brain stimulation for treating isolated orofacial dystonia.

BACKGROUND: Isolated orofacial dystonia is a rare segmental neurological disorder that affects the eye, mouth, face, and jaws. Current literature on pallidal surgery for orofacial dystonia is limited to case reports and small-scale studies. This study was to investigate clinical outcomes of deep brain stimulation (DBS) of the globus pallidus internus (GPi) in patients with isolated orofacial dystonia. METHODS: Thirty-six patients who underwent GPi DBS at Incheon St. Mary's Hospital, The Catholic University of Korea, between 2014 and 2019 were included in this study. Burke-Fahn-Marsden Dystonia Rating Scale, Unified Dystonia Rating Scale, and Global Dystonia Severity Rating Scale were retrospectively retrieved for analysis before surgery, at 6-month follow-up as short-term outcome, and at follow-up over 1 year (12 months to 69 months) as long-term results. RESULTS: Mean total BFMDRS-M scores at the three time points (baseline, 6 months, and over 1 year follow-up) were 11.6 ± 4.9, 6.1 ± 5.2 (50.3 ± 29.9% improvement, p < 0.05), and 4.3 ± 4.2 (65.0 ± 24.2% improvement, p < 0.05), respectively. In terms of UDRS and GDS, improvement rates were 45.1% (p < 0.001) and 47.7% (p < 0.001) at 6 months, and 63.8% (p < 0.001) and 65.7% (p < 0.001) at over 1 year after surgery, respectively. CONCLUSIONS: Bilateral GPi DBS in isolated orofacial dystonia can be effective if conservative treatment option fails. Its benefit is not only observed in a short term, but also maintained in a long-term follow-up.

Clinical Outcomes after Spinal Cord Stimulation According to Pain Characteristics.

OBJECTIVE: Spinal cord stimulation (SCS) is an effective treatment for chronic neuropathic pain. However, its clinical efficacy in regard to specific types of pain has not been well studied. The primary objective of this study was to retrospectively analyze the clinical outcomes of paddle-type SCS according to the type of neuropathic pain. METHODS: Seventeen patients who underwent paddle-lead SCS at our hospital were examined. Clinical outcomes were evaluated pre- and postoperatively (3 months, 1 year, and last follow-up) using the Neuropathic Pain Symptom Inventory (NPSI). The NPSI categorizes pain as superficial, deep, paroxysmal, evoked, or dysesthesia and assess the duration of the pain (pain time score). Changes in NPSI scores were compared with change in Visual analogue scale (VAS) scores. RESULTS: After SCS, the pain time score improved by 45% (independent t-test, p=0.0002) and the deep pain score improved by 58% (independent t-test, p=0.001). Improvements in the pain time score significantly correlated with improvements in the VAS score (r=0.667, p=0.003, Spearman correlation). Additionally, the morphine milligram equivalent value was markedly lower after vs. before surgery (~49 mg, pared t-test, p=0.002). No preoperative value was associated with clinical outcome. CONCLUSION: The NPSI is a useful tool for evaluating the therapeutic effects of SCS. Chronic use of a paddle-type spinal cord stimulation improved the deep pain and the pain time scores.

Side predilections of offending arteries in hemifacial spasm.

The side predilections of various offending arteries in hemifacial spasm (HFS) have not been well studied. The relationship between clinical and radiological features of HFS and offending arteries were investigated in the present study. A retrospective analysis of 370 patients who underwent microvascular decompression for HFS was performed. The patients were divided into four groups based on the offending arteries, namely anterior inferior cerebellar artery (AICA), posterior inferior cerebellar artery (PICA), vertebral artery, and multiple offending arteries. Affected side, age at onset, presence of hypertension, and sigmoid sinus area and dominance were compared between groups. The mean age of patients with a left HFS was significantly greater than that of patients with a right HFS (P=0.009). The AICA affected primarily the right side and PICA and multiple offending arteries the left side (P<0.001). Side of sigmoid sinus dominance was significantly different among groups (P<0.001). The offending arteries in HFS may be related to these differences. AICA was associated with right-sided symptoms, younger age at onset, and presence of left dominant sigmoid sinus, while PICA was associated with left-sided symptoms, older age at onset, and smaller right sigmoid sinus area.

Effectiveness of selective peripheral denervation in combination with pallidal deep brain stimulation for the treatment of cervical dystonia.

BACKGROUND: Selective peripheral denervation (SPD) and deep brain stimulation of the globus pallidus (GPi-DBS) are available surgical options for patients with medically refractory cervical dystonia (CD). There are few data available concerning whether patients who have unsatisfactory treatment effects after primary surgery benefit from a different type of subsequent surgery. The aim of this study was to assess whether combining these surgical procedures (SPD plus GPi-DBS) was effective in patients with unsatisfactory treatment effects after their initial surgery. METHODS: Forty-one patients with medically refractory idiopathic CD underwent SPD and/or GPi-DBS. Patients who were dissatisfied with their primary surgery (SPD or GPi DBS) elected to subsequently undergo a different type of surgery. These patients were assessed with the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS). RESULTS: SPD alone and GPi-DBS alone were performed in 16 and 21 patients, respectively. Four patients had unsatisfactory treatment effects after the initial surgery and subsequently underwent another type of surgery. Among them, two patients with persistent dystonia after SPD subsequently underwent GPi-DBS, and two other patients who had insufficient treatment effects following GPi-DBS were subsequently treated with SPD. All of these patients experienced sustained improvement from the combined surgical procedures according to the TWSTRS score during a long-term follow-up of 12-90 months. CONCLUSIONS: Patients with unsatisfactory treatment effects after an SPD or GPi-DBS experienced improvement from subsequently undergoing other types of surgery. Therefore, combined surgical procedures are additional surgical options with good outcomes in the treatment of patients with residual symptoms after their initial surgery.

Intraoperative facial electromyography and brainstem auditory evoked potential findings in microvascular decompression for hemifacial spasm: correlation with postoperative delayed facial palsy.

BACKGROUND: Delayed facial palsy (DFP) after microvascular decompression (MVD) in patients with hemifacial spasm (HFS) is not uncommon, but the cause remains unknown. OBJECTIVES: To assess whether intraoperative electromyography (EMG) and brainstem auditory evoked potential (BAEP) can predict DFP after MVD. METHODS: Between September 2009 and February 2011 we examined 86 patients, 9 of whom (10.4%) developed DFP after MVD on the same side. All patients underwent MVD and were followed-up for a median period of 13 months (range 6-22). We retrospectively examined intraoperative facial EMG and BAEP findings using our MVD patients' registry. We excluded secondary HFS and immediate postoperative facial palsy after MVD in this study. We assessed the prevalence and clinical characteristics of DFP and compared EMG and BAEP findings between DFP and non-DFP groups. RESULTS: All patients recovered completely, with a mean time to recovery of 37.8 days (range 22-57). There were no significant differences between DFP and non-DFP patients in terms of the amplitude and latency of intraoperative EMG and BAEP. CONCLUSION: The usefulness of intraoperative facial EMG and BAEP is limited and cannot predict DFP after MVD for HFS. We speculate that DFP after MVD is not associated with permanent nerve damage according to the EMG findings.

Comparison of treatment results between selective peripheral denervation and deep brain stimulation in patients with cervical dystonia.

BACKGROUND/AIMS: Cervical dystonia (CD) is the most common form of focal dystonia. The treatment options for CD include medical therapy and surgery. The 3 basic types of CD are tonic, phasic and tremulous. Selective peripheral denervation (SPD) and globus pallidus internus (GPi) deep brain stimulation (DBS) have been developed as therapeutic options for the treatment of CD. METHODS: Between 1997 and 2009, 24 patients with CD underwent operations: either SPD (n = 16) or DBS (n = 8). The mean follow-up period was 29.5 months (range = 2-59). The mean age at onset of symptoms was 46.6 years (range = 27-65). The patients were evaluated with the subjective scores and the Toronto Western Spasmodic Torticollis Scale scores. RESULTS: All patients showed gradual improvement after SPD and DBS. No statistically significant differences were seen between the SPD group and the DBS group. However, there was a trend toward greater pain reduction in the DBS group (p = 0.094). CONCLUSION: Both the SPD group and the DBS group showed successful improvement in their Toronto Western Spasmodic Torticollis Scale scores as well as subjective scores. The GPi DBS group showed a remarkable improvement on the pain scale and there was a trend toward greater pain reduction in the DBS group.

Effect of various surgical modalities in recurrent or persistent trigeminal neuralgia.

BACKGROUND/AIMS: In recurrent or persistent idiopathic trigeminal neuralgia (TN) after initial operation, additional surgical procedures may be required. There are numerous articles reporting the outcomes of additional surgical treatment and it is unclear how best to treat patients with recurrent or persistent TN. We evaluated the subsequent therapeutic options for recurrent or persistent TN. METHODS: The study was a retrospective study. The authors reviewed 29 patients (15 female/14 male) who underwent retreatments for recurrent or persistent symptoms after an initial operation. RESULTS: The mean follow-up duration was 56.4 months (range 12-78.7) from final treatment. Patients underwent a mean of 2.3 retreatments with a mean period of 26 months (range 1-72) between treatments. Final treatments were as follows: microvascular decompression (MVD) in 12 patients, percutaneous rhizotomy in 10, and radiosurgery in 7. Of the 29 patients, after final treatments, 9 patients (31%) achieved excellent results and 15 (52%) good results. Failure results were seen in 17% of patients with recurrent TN. CONCLUSION: In this study the authors demonstrate that percutaneous rhizotomy is recommended for most patients with recurrent pain after MVD, and MVD can be effective in patients with a history of failed percutaneous procedures. Radiosurgery can be utilized to treat those that have not responded to other surgical modalities.

Stereotactic spine radiosurgery for intradural and intramedullary metastasis.

OBJECT: Stereotactic radiosurgery (SRS) has become an important treatment alternative to surgery for a variety of spinal lesions. However, the use of SRS in the management of intradural intramedullary (IDIM) metastasis remains controversial. The aim of this study was to determine the clinical efficacy and safety of SRS for treatment of IDIM metastasis. METHODS: Nine patients with 11 IDIM metastases treated with SRS at Henry Ford Hospital were retrospectively reviewed. The mean age at presentation was 50 years, with a range of 14-71 years. There were 4 intradural extramedullary and 7 intramedullary lesions. The radiosurgery procedure used techniques of image-guided and intensitymodulated radiation. The mean treatment dose was 13.8 Gy, with a range of 10-16 Gy. All patients had clinical follow-up (except in 1 lesion), with an emphasis on initial symptoms and ambulatory status, and 8 patients (9 lesions) had imaging studies. The median follow-up duration was 10 months. RESULTS: The presenting symptoms were improved in 8 (80%) of 10 evaluable lesions, unchanged in 1 case, and worsened in 1 case. Radiographic responses were seen as follows: complete response in 2 (22%) of 9; partial response in 3 (33%) of 9; stable disease in 3 (33%) of 9; and progressive disease in 1 (11%) of 9. After radiosurgery, 7 patients (78%) remained ambulatory until the last follow-up visit. The overall median survival time after SRS was 8 months, with a range of 2-19 months. No radiation toxicity was detected clinically during the follow-up period. CONCLUSIONS: Despite the fact that this was a small series of patients with IDIM metastasis who had limited treatment options, SRS appears to be an effective and safe method of treating patients with these lesions.

Unusual causes and presentations of hemifacial spasm.

OBJECTIVE: To evaluate unusual possible causes and clinical presentations of hemifacial spasm (HFS). METHODS: The authors reviewed 1642 cases of HFS. Assessments were based on clinical features, 3-dimensional time-of-flight magnetic resonance angiography, and surgical findings. Causes other than neurovascular compression at the root exit zone of the facial nerve were investigated and unusual clinical presentations were noted. RESULTS: Nine (0.5%) patients had a secondary causative structural lesion, 7 patients had a tumor, and the remaining 2 had a vascular malformation. Direct compression by dolichoectatic vertebrobasilar artery was noted in 12 (0.7%) patients. In 7 (0.4%) patients, only the distal portion of the facial nerve was compressed, and five (0.3%) had only venous compression. Bilateral HFS and tic convulsif were encountered in 7 (0.4%) and 6 (0.37%) patients, respectively. Fifty-six (3.4%) patients were younger than 30 years old at the time of microvascular decompression. CONCLUSION: HFS can result from tumor, vascular malformation, and dolichoectatic artery. Therefore, appropriate preoperative radiological investigations are crucial to achieve a correct diagnosis. The authors emphasize that distal compression or only venous compression can be responsible for persistent or recurrent symptoms postoperatively. In cases of bilateral HFS, a definite differential diagnosis is necessary for appropriate therapy. MVD is recommended as the treatment of choice in patients younger than 30 years old or patients with painful tic convulsif.

Isolated pineal region metastasis of small cell lung cancer.

The pineal region is an unusual site for brain metastasis and most metastatic pineal lesions are asymptomatic. Rarely the symptoms of metastatic involvement of the pineal gland precede those of the primary tumor or other metastatic sites. An 83 year-old man presented with gait disturbance and limitation of upward gaze. Brain MRI showed homogeneous enhancement of a solitary mass in the pineal region with obstructive hydrocephalus. A stereotactic biopsy was performed, and small cell carcinoma was diagnosed. A systemic investigation for the primary lesion subsequently revealed small cell carcinoma of the lung. The patient was referred for radiotherapy and chemotherapy. Although rare, metastatic tumor should be considered in the differential diagnosis of pineal region tumors, particularly in elderly patients.

Therapeutic effects of Holmium-166 chitosan complex in rat brain tumor model.

This study examined the effectiveness of Holmium-166 (Ho-166) chitosan complex therapy for a malignant glioma. Cultured C6 glioma cells (100,000 in 5 microl) were injected into the caudate/putamen of 200-250 gram Wistar rats. Five days later, a Ho-166 chitosan complex was injected into the same site of the glioma injection. Four injection doses were administered: the control group received PBS 10 microl, group 1 received an injection of 100 microCi (10 microl), group 2 received an injection of 50 microCi (5 microl), and group 3 received an injection of 10 microCi (1 microl). The average tumor volume for each group was 1.385 mm3 for the control group, 0.036 mm3 for group 1, 0.104 mm3 for group 2, and 0.111 mm3 for group 3. Compared with the control group, the size of the tumors in groups 1, 2 and 3 was reduced by an average of 97.4%, 92.5% and 91.9%, respectively. The Kaplan-Meier survival curve of group 2 was the longest, followed by groups 3, group 1 and the control. The mean survival was 22.8, 59, 60, and 44.6 days for the control group and groups 3, 2 and 1, respectively. H-E staining revealed that group 2 yielded the best results in the destruction of the malignant glioma. TUNEL staining and immunohistochemical studies indicated apoptotic features. The Ho-166 chitosan complex proved to be effective in destroying the malignant glioma.