Long-term efficacy, prognostic factors, and safety of deep brain stimulation in patients with refractory Tourette syndrome: A single center, single target, retrospective study.

BACKGROUND: To evaluate the long-term efficacy, prognostic factors, and safety of posteroventral globus pallidus internus deep brain stimulation (DBS) in patients with refractory Tourette syndrome (RTS). METHODS: This retrospective study recruited 61 patients with RTS who underwent posteroventral globus pallidus internus (GPi) DBS from January 2010 to December 2020 at the Chinese People's Liberation Army General Hospital. The Yale Global Tic Severity Scale (YGTSS), Yale-Brown Obsessive-Compulsive Scale (YBOCS), Beck Depression Inventory (BDI), Gilles de la Tourette Syndrome Quality-of-Life Scale (GTS-QOL) were used to evaluate the preoperative and postoperative clinical condition in all patients. Prognostic factors and adverse events following surgery were analyzed. RESULTS: Patient follow up was conducted for an average of 73.33 ± 28.44 months. The final postoperative YGTSS (32.39 ± 22.34 vs 76.61 ± 17.07), YBOCS (11.26 ± 5.57 vs 18.31 ± 8.55), BDI (14.36 ± 8.16 vs 24.79 ± 11.03) and GTS-QOL (39.69 ± 18.29 vs 78.08 ± 14.52) scores at the end of the follow-up period were significantly lower than those before the surgery (p < 0.05). While age and the duration of follow-up were closely related to prognosis, the disease duration and gender were not. No serious adverse events were observed and only one patient exhibited symptomatic deterioration. CONCLUSIONS: Posteroventral-GPI DBS provides long-term effectiveness, acceptable safety and can improve the quality of life in RTS patients. Moreover, DBS is more successful among younger patients and with longer treatment duration.

Therapeutic Effect of Hypofractionated Stereotactic Radiotherapy Using CyberKnife for High Volume Cavernous Sinus Cavernous Hemangiomas.

OBJECTIVE: To evaluate the efficacy and safety of hypofractionated stereotactic radiotherapy using CyberKnife for high volume cavernous sinus cavernous hemangiomas. MATERIALS AND METHODS: We collected data from 12 patients with high volume cavernous sinus cavernous hemangiomas treated with hypofractionated stereotactic radiotherapy using CyberKnife in our institute, including 2 men and 10 women/female child, aged 4 to 60 years. Initial tumor volumes ranged from 11.8 to 96.6 cm3 with a median of 24.3 cm3. Irradiation doses were 19.5 Gy with 3 fractions in 2 patients, 21 Gy with 3 fractions in 8 patients, 25 Gy with 5 fractions in 1 patient, and 30 Gy with 3 fractions in 1 patient. We used 109 to 155 beams during treatment, and target volumes reached over 95% of the prescribed dose. Follow-up ranged from 3 to 54 months. We evaluated the efficacy and safety of the CyberKnife system based on changes in the diagnostic images and involved cranial nerves or symptoms. RESULTS: Of the 12 patients, 11 were followed for 3 to 54 months with a mean follow-up of 16.3 months; 1 patient was lost to in-person follow-up. Lesion volumes in the followed 11 patients were calculated after fractionated radiotherapy. All tumor volumes decreased (28.6%-94.1%) and symptoms improved (including blurred vision, visual field defects, diplopia, headaches, and facial numbness) after therapy. Postoperative magnetic resonance images revealed a tumor volume range of 2.8 to 41.0 cm3 (median, 6.5 cm3), significantly lower compared with the pretreatment range of 11.8 to 70.1 cm3 (median, 24.3 cm3; T = 0.00, P = .003 < .05). A single patient experienced radiotherapy-related cerebral edema, which resolved after 5 days of mannitol and dexamethasone. CONCLUSIONS: Based on the current results, though preliminary, hypofractionated stereotactic radiotherapy using CyberKnife is an effective and safe alternative for high volume cavernous sinus cavernous hemangiomas and is the recommended primary treatment in high-risk patients with this condition.

Partial improvement in performance of patients with severe Alzheimer's disease at an early stage of fornix deep brain stimulation.

Deep brain stimulation is a therapy for Alzheimer's disease (AD) that has previously been used for mainly mild to moderate cases. This study provides the first evidence of early alterations in performance induced by stimulation targeted at the fornix in severe AD patients. The performance of the five cases enrolled in this study was scored with specialized assessments including the Mini-Mental State Examination and Clinical Dementia Rating, both before and at an early stage after deep brain stimulation. The burden of caregivers was also evaluated using the Zarit Caregiver Burden Interview. As a whole, the cognitive performance of patients remained stable or improved to varying degrees, and caregiver burden was decreased. Individually, an improved mental state or social performance was observed in three patients, and one of these three patients showed remarkable improvement in long-term memory. The conditions of another patient deteriorated because of inappropriate antipsychotic medications that were administered by his caregivers. Taken together, deep brain stimulation was capable of improving some cognitive aspects in patients with severe AD, and of ameliorating their emotional and social performance, at least at an early stage. However, long-term effects induced by deep brain stimulation in patients with severe AD need to be further validated. More research should focus on clarifying the mechanism of deep brain stimulation. This study was registered with ClinicalTrials.gov (NCT03115814) on April 14, 2017.

Preoperative Heart Rate Variability as Predictors of Vagus Nerve Stimulation Outcome in Patients with Drug-resistant Epilepsy.

Vagus nerve stimulation (VNS) is an adjunctive treatment for drug-resistant epilepsy (DRE). However, it is still difficult to predict which patients will respond to VNS treatment and to what extent. We aim to explore the relationship between preoperative heart rate variability (HRV) and VNS outcome. 50 healthy control subjects and 63 DRE patients who had received VNS implants and had at least one year of follow up were included. The preoperative HRV were analyzed by traditional linear methods and heart rhythm complexity analyses with multiscale entropy (MSE). DRE patients had significantly lower complexity indices (CI) as well as traditional linear HRV measurements than healthy controls. We also found that non-responders0 had significantly lower preoperative CI including Area 1-5, Area 6-15 and Area 6-20 than those in the responders0 while those of the non-responders50 had significantly lower RMSSD, pNN50, VLF, LF, HF, TP and LF/HF than the responders50. In receiver operating characteristic (ROC) curve analysis, Area 6-20 and RMSSD had the greatest discriminatory power for the responders0 and non-responders0, responders50 and non-responders50, respectively. Our results suggest that preoperative assessment of HRV by linear and MSE analysis can help in predicting VNS outcomes in patients with DRE.

A portion of inhibitory neurons in human temporal lobe epilepsy are functionally upregulated: an endogenous mechanism for seizure termination.

MAIN PROBLEM: Epilepsy is one of the more common neurological disorders. The medication is often ineffective to the patients suffering from intractable temporal lobe epilepsy (TLE). As their seizures are usually self-terminated, the elucidation of the mechanism underlying endogenous seizure termination will help to find a new strategy for epilepsy treatment. We aim to examine the role of inhibitory interneurons in endogenous seizure termination in TLE patients. METHODS: Whole-cell recordings were conducted on inhibitory interneurons in seizure-onset cortices of intractable TLE patients and the temporal lobe cortices of nonseizure individuals. The intrinsic property of the inhibitory interneurons and the strength of their GABAergic synaptic outputs were measured. The quantitative data were introduced into the computer-simulated neuronal networks to figure out a role of these inhibitory units in the seizure termination. RESULTS: In addition to functional downregulation, a portion of inhibitory interneurons in seizure-onset cortices were upregulated in encoding the spikes and controlling their postsynaptic neurons. A patch-like upregulation of inhibitory neurons in the local network facilitated seizure termination. The upregulations of both inhibitory neurons and their output synapses synergistically shortened seizure duration, attenuated seizure strength, and terminated seizure propagation. CONCLUSION: Automatic seizure termination is likely due to the fact that a portion of the inhibitory neurons and synapses are upregulated in the seizure-onset cortices. This mechanism may create novel therapeutic strategies to treat intractable epilepsy, such as the simultaneous upregulation of cortical inhibitory neurons and their output synapses.

Combining pyramidal tract mapping, microscopic-based neuronavigation, and intraoperative magnetic resonance imaging improves outcome of epilepsy foci resection in the sensorimotor cortex.

AIM: To explore the clinical value of combining pyramidal tract mapping, microscopic-based neuronavigation, and intraoperative magnetic resonance imaging (iMRI) in the surgical treatment of epileptic foci involving sensorimotor cortex. MATERIAL AND METHODS: We retrospectively analyzed 69 patients with focal epilepsy involving motor and sensory cortex. The surgical operations in Group I (n=38) were performed under the guidance of conventional neuronavigation, and the operations of Group II (n=31) were aided by combining pyramidal tract mapping, microscopic-based neuronavigation and the iMRI technique. Chi square test was used to compare seizure outcome and neurological deficits across groups. RESULTS: 7 patients (18.4%) in Group I, and 3 patients (9.7%) in Group II didn't recover to the level of preoperative strength within one year post-operation. The 2-year follow-up survey showed that more patients in Group II compared to Group I (71% vs. 55.3%, p=0.181) had a good outcome (Engel class I ~ II). CONCLUSION: The techniques of combining pyramidal tract mapping, microscopic-based neuronavigation and iMRI aid in precise mapping and hence resection of epileptic foci in sensorimotor cortex, which lead to improvement of surgical efficacy and significant reduction of postoperative loss of function.