Expectations and Level of Satisfaction of the Patient with Parkinson’s Disease Undergoing Deep Brain Stimulation Surgery at the National Institute of Neurology and Neurosurgery

Background: Deep brain stimulation (DBS) is an established treatment for patients with advanced Parkinson’s disease (PD). Reports show continued patient satisfaction after surgery despite not maintaining clinical improvement as measured by evolution scales. Objectives: The present study sought to explore expectations and level of satisfaction in patients after DBS surgery with a semi-structured questionnaire and subsequent correlation with functional scales, Quality of Life (QoL), and motor and non-motor symptoms. Methods: We performed descriptive statistics to represent demographic data, Wilcoxon rank tests to determine significant differences, and Spearman correlation between the applied scales. Results: We evaluated 20 patients with a history of DBS surgery. 45% were female, with a mean age of 55.7 ± 14.15 years, a mean disease duration of 13.42 ± 8.3 years, and a mean time after surgery of 3.18 ± 1.86 years. Patients reported surgery meeting expectations in 85.5% and continued satisfaction in 92%. These two variables showed a significant correlation. Conclusions: This sample of patients remained satisfied after DBS surgery, although we found no differences in motor and non-motor clinimetric scales. Further studies are needed to confirm the importance of assessing quality of life in patients with DBS.

Sex modulates the outcome of subthalamic nucleus deep brain stimulation in patients with Parkinson's disease

There are many documented sex differences in the clinical course,symptom expression profile,and treatment response of Parkinson’s disease,creating additional challenges for patient management.Although subthalamic nucleus deep brain stimulation is an established therapy for Parkinson’s disease,the effects of sex on treatment outcome are still unclear.The aim of this retrospective observational study,was to examine sex differences in motor symptoms,nonmotor symptoms,and quality of life after subthalamic nucleus deep brain stimulation.Outcome measures were evaluated at 1 and 12 months post-operation in 90 patients with Parkinson’s disease undergoing subthalamic nucleus deep brain stimulation aged 63.00±8.01 years(55 men and 35 women).Outcomes of clinical evaluations were compared between sexes via a Student’s t-test and within sex via a paired-sample t-test,and generalized linear models were established to identify factors associated with treatment efficacy and intensity for each sex.We found that subthalamic nucleus deep brain stimulation could improve motor symptoms in men but not women in the on-medication condition at 1 and 12 months post-operation.Restless legs syndrome was alleviated to a greater extent in men than in women.Women demonstrated poorer quality of life at baseline and achieved less improvement of quality of life than men after subthalamic nucleus deep brain stimulation.Furthermore,Hoehn-Yahr stage was positively correlated with the treatment response in men,while levodopa equivalent dose at 12 months post-operation was negatively correlated with motor improvement in women.In conclusion,women received less benefit from subthalamic nucleus deep brain stimulation than men in terms of motor symptoms,non-motor symptoms,and quality of life.We found sex-specific factors,i.e.,Hoehn-Yahr stage and levodopa equivalent dose,that were related to motor improvements.These findings may help to guide subthalamic nucleus deep brain stimulation patient selection,prognosis,and stimulation programming for optimal therapeutic efficacy in Parkinson’s disease.

The Application of Deep Brain Stimulation for Parkinson’s Disease on the Motor Pathway:A Bibliometric Analysis across 10 Years

Background and Objective Since its initial report by James Parkinson in 1817,Parkinson’s disease(PD)has remained a central subject of research and clinical advancement.The disease is estimated to affect approximately 1%of adults aged 60 and above.Deep brain stimulation,emerging as an alternative therapy for end-stage cases,has offered a lifeline to numerous patients.This review aimed to analyze publications pertaining to the impact of deep brain stimulation on the motor pathway in patients with PD over the last decade.Methods Data were obtained from the Web of Science Core Collection through the library of Huazhong University of Science and Technology(China).The search strategy encompassed the following keywords:“deep brain stimulation”,“Parkinson’s disease”,“motor pathway”,and“human”,from January 1,2012,to December 1,2022.Additionally,this review visualized the findings using the Citespace software.Results The results indicated that the United States,the United Kingdom,Germany,and China were the primary contributors to this research field.University College London,Capital Medical University,and Maastricht University were the top 3 research institutions in the research area.Tom Foltynie ranked first with 6 publications,and the journals of Brain and Brain Stimulation published the greatest number of relevant articles.The prevailing research focal points in this domain,as determined by keywords“burst analysis”,“encompassed neuronal activity”,“nucleus”,“hyper direct pathway”,etc.Conclusion This study has provided a new perspective through bibliometric analysis of the deep brain stimulation therapy for treating patients with PD,which can shed light on future research to advance our comprehension of this particular field of study.

Research progress in the efficacy of deep brain stimulation with different targets in Parkinson's disease

Parkinson's disease(PD)is a chronic progressive neurodegenerative disease.Deep brain stimulation(DBS)is an effective treatment for patients with advanced PD.There are many DBS targets for PD,including subthalamic nucleus(STN),globus pallidus(GPi),meso-ventral thalamic nucleus(VIM),pontine peduncle nucleus(PPN),posterior subthalamic region(PSA)and zonation of undetermined zone(ZI).This paper summarizes the efficacy of each target in the treatment of PD with DBS,not only makes a systematic analysis and comparison of motor symptoms,but also makes a detailed description of the efficacy of non-motor symptoms,so as to provide a personalized treatment basis for PD patients to select appropriate target targets in DBS.

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.

Deep Brain Stimulation──A new treatment for tinnitus

Intractable tinnitus can lead to serious consequences. Study evidence indicates that the central nervous system is involved in generation and maintenance of chronic tinnitus and that tinnitus and other neurologic symptoms such as chronic pain may share similar mechanisms. Brain ablation and stimulation are used to treat chronic pain with success. Recent studies showed that ablation and stimulation in non-auditory areas resulted in tinnitus improvement. Deep brain stimulation (DBS) may be an alternative treatment for intractable tinnitus and deserves further study.

The treatment of Parkinson's disease with deep brain stimulation: current issues

Deep brain stimulation has become a well-established symptomatic treatment for Parkinson＇s disease during the last 25 years. Besides improving motor symptoms and long-term motor complications, positive effects on patients＇ mobility, activities of daily living, emotional well-being and health-related quality of life have been recognized. Apart from that, numerous clinical trials analyzed effects on non-motor symptoms and side effects of deep brain stimulation. Several technical issues and stimulation paradigms have been and are still being developed to optimize the therapeutic effects, minimize the side effects and facilitate handling. This review summarizes current therapeutic issues, i.e., patient and target selection, surgical procedure and programming paradigms. In addition it focuses on neuropsychological effects and side effects of deep brain stimulation.

Application of Preoperative CT/MRI Image Fusion in Target Positioning for Deep Brain Stimulation

Objective To explore the efficacy of target positioning by preoperative CT/MRI image fusion technique in deep brain stimulation.Methods We retrospectively analyzed the clinical data and images of 79 cases(68 with Parkinson's disease,11 with dystonia) who received preoperative CT/MRI image fusion in target positioning of subthalamic nucleus in deep brain stimulation.Deviation of implanted electrodes from the target nucleus of each patient were measured.Neurological evaluations of each patient before and after the treatment were performed and compared.Complications of the positioning and treatment were recorded.Results The mean deviations of the electrodes implanted on X,Y,and Z axis were 0.5 mm,0.6 mm,and 0.6 mm,respectively.Postoperative neurologic evaluations scores of unified Parkinson's disease rating scale(UPDRS) for Parkinson's disease and Burke-Fahn-Marsden Dystonia Rating Scale(BFMDRS) for dystonia patients improved significantly compared to the preoperative scores(P<0.001); Complications occurred in 10.1%(8/79) patients,and main side effects were dysarthria and diplopia.Conclusion Target positioning by preoperative CT/MRI image fusion technique in deep brain stimulation has high accuracy and good clinical outcomes.

A review of computational modeling and deep brain stimulation:applications to Parkinson’s disease

Biophysical computational models are complementary to experiments and theories,providing powerful tools for the study of neurological diseases.The focus of this review is the dynamic modeling and control strategies of Parkinson’s disease(PD).In previous studies,the development of parkinsonian network dynamics modeling has made great progress.Modeling mainly focuses on the cortex-thalamus-basal ganglia(CTBG)circuit and its sub-circuits,which helps to explore the dynamic behavior of the parkinsonian network,such as synchronization.Deep brain stimulation(DBS)is an effective strategy for the treatment of PD.At present,many studies are based on the side effects of the DBS.However,the translation from modeling results to clinical disease mitigation therapy still faces huge challenges.Here,we introduce the progress of DBS improvement.Its specific purpose is to develop novel DBS treatment methods,optimize the treatment effect of DBS for each patient,and focus on the study in closed-loop DBS.Our goal is to review the inspiration and insights gained by combining the system theory with these computational models to analyze neurodynamics and optimize DBS treatment.

Chronic deep brain stimulation of the subthalamic nucleus in a monkey model of hemiparkinsonian Dynamic alterations of extracellular fluid dopamine levels in corpus striatum

BACKGROUND： Although experimental studies have utilized high-frequency stimulation in animal models, few reports have focused on long-term subthalamic nucleus deep brain stimulation （STN DBS） in Parkinson＇s disease （PD） animal models. OBJECTIVE： The present study simulated long-term DBS system and utilized microdialysis technology to study the influence of STN DBS on levels of extracellular dopamine （DA） and its metabolites, homovanillic acid （HVA） and dihydroxy phenyl acetic acid, in the corpus striatum of a hemiparkinsonian monkey model. DESIGN, TIME AND SETTING： A controlled animal study was performed at the Neurosurgery Laboratory, Changhai Hospital of the Second Military Medical University of Chinese PLA between January 2004 and December 2007. MATERIALS： 1-methy-4-phenyl-1, 2, 3, 6-tetrahydropyrindinewas （MPTP） purchased from Sigma, USA. Type-3389 DBS electrode and type-7246 pulse generator were provided by Medtronic, USA. METHODS： Hemiparkinsonism was induced in 2 male, adult Rhesus Macaque monkeys through unilateral internal carotid artery infusion of MPTP. Following model establishment, stimulation electrodes were implanted in the right STN, and chronic high-frequency stimulation （60 μs pulse width, 130 Hz frequency, and 1.5 2.0 V pressure） was performed. MAIN OUTCOME MEASURES： Prior to, and 2 hours, 8 hours, 1 week, 1 month, and 2 months after DBS, samples were collected from the caudate nucleus and putamen using microdialysis technology Extracellular levels of DA and its metabolites were measured using high-performance liquid chromatography and electrochemical detection （HPLC-ECD） methods. RESULTS： At 8 hours, 1 week, 1 month, and 2 months after DBS, DA levels in the putamen and caudate nucleus were increased on the electrode-implanted side by 39%, 91%, 111%, and 114% and 31%, 91%, 106%, and 102%, respectively. The DA turnover rate （HVA/DA） was increased in the putamen and caudate nucleus by 186% and 91%, respectively, at 8 hours after DBS, while there was no significant difference at 1 week, 1 month, and 2 months after DBS. CONCLUSION： Effective, chronic, high frequency DBS increased extracellular DA levels in the corpus striatum, which could be one of mechanisms involved in the effects of STN DBS.

Voltage adjustment improves rigidity and tremor in Parkinson's disease patients receiving deep brain stimulation

Deep brain stimulation of the subthalamic nucleus is recognized as the most effective treatment for moderate and advanced Parkinson＇s disease. Programming of the stimulation parameters is important for maintaining the efficacy of deep brain stimulation. Voltage is consid- ered to be the most effective programming parameter. The present study is a retrospective analysis of six patients with Parkinson＇s disease （four men and two women, aged 37-65 years）, who underwent bilateral deep brain stimulation of the subthalamic nucleus at the First Affiliated Hospital of Sun Yat-sen University, China, and who subsequently adjusted only the stimulation voltage. We evaluated motor symptom severity using the Unified Parkinson＇s Disease Rating Scale Part III, symptom progression using the Hoehn and Yahr scale, and the levodopa equivalent daily dose, before surgery and 1 and 2 years after surgery. The 2-year follow-up results show that rigidity and tremor improved, and clinical symptoms were reduced, while pulse width was maintained at 60 ps and frequency at 130 Hz. Voltage adjust- ment alone is particularly suitable for patients who cannot tolerate multiparameter program adjustment. Levodopa equivalent daily dose was markedly reduced 1 and 2 years after surgery compared with baseline. Our results confirm that rigidity, tremor and bradykinesia can be best alleviated by voltage adjustment. The trial was registered at ClinicalTrials.gov （identifier： NCT01934881）.

Vascular changes caused by deep brain stimulation using double-dose gadolinium-enhanced brain MRI

We retrospectively analyzed the clinical data of 32 patients with medically intractable idiopathic Parkinson＇s disease who had undergone staged bilateral deep brain stimulation of the subtha-lamic nuclei from January 2007 to May 2011. The vascularture of the patients who received two deep brain stimulations was detected using double-dose gadolinium-enhanced brain MRI. The dimensions of straight sinus, superior sagittal sinus, ipsilateral internal cerebral vein in the tha- lamic branch and ipsilateral anterior caudate vein were reduced. These findings demonstrate that bilateral deep brain stimulation of the subthalamic nuclei affects cerebral venous blood flow.

Deep brain stimulation for obsessive-compulsive disorder:A systematic review of worldwide experience after 20 years

BACKGROUND Twenty years after its first use in a patient with obsessive-compulsive disorder(OCD),the results confirm that deep brain stimulation(DBS)is a promising therapy for patients with severe and resistant forms of the disorder.Nevertheless,many unknowns remain,including the optimal anatomical targets,the best stimulation parameters,the long-term(LT)effects of the therapy,and the clinical or biological factors associated with response.This systematic review of the articles published to date on DBS for OCD assesses the short and LT efficacy of the therapy and seeks to identify predictors of response.AIM To summarize the existing knowledge on the efficacy and tolerability of DBS in treatment-resistant OCD.METHODS A comprehensive search was conducted in the PubMed,Cochrane,Scopus,and ClinicalTrials.gov databases from inception to December 31,2020,using the following strategy:“(Obsessive-compulsive disorder OR OCD)AND(deep brain stimulation OR DBS).”Clinical trials and observational studies published in English and evaluating the effectiveness of DBS for OCD in humans were included and screened for relevant information using a standardized collection tool.The inclusion criteria were as follows:a main diagnosis of OCD,DBS conducted for therapeutic purposes and variation in symptoms of OCD measured by the Yale-Brown Obsessive-Compulsive scale(Y-BOCS)as primary outcome.Data were analyzed with descriptive statistics.RESULTS Forty articles identified by the search strategy met the eligibility criteria.Applying a follow-up threshold of 36 mo,29 studies(with 230 patients)provided information on short-term(ST)response to DBS in,while 11(with 155 patients)reported results on LT response.Mean follow-up period was 18.5±8.0 mo for the ST studies and 63.7±20.7 mo for the LT studies.Overall,the percentage of reduction in Y-BOCS scores was similar in ST(47.4%)and LT responses(47.2%)to DBS,but more patients in the LT reports met the criteria for response(defined as a reduction in Y-BOCS scores>35%:ST,60.6%vs LT,70.7%).According to the results,the response in the first year predicts the extent to which an OCD patient will benefit from DBS,since the maximum symptom reduction was achieved in most responders in the first 12-14 mo after implantation.Reports indicate a consistent tendency for this early improvement to be maintained to the mid-term for most patients;but it is still controversial whether this improvement persists,increases or decreases in the long term.Three different patterns of LT response emerged from the analysis:49.5% of patients had good and sustained response to DBS,26.6% were non responders,and 22.5% were partial responders,who might improve at some point but experience relapses during follow-up.A significant improvement in depressive symptoms and global functionality was observed in most studies,usually(although not always)in parallel with an improvement in obsessive symptoms.Most adverse effects of DBS were mild and transient and improved after adjusting stimulation parameters;however,some severe adverse events including intracranial hemorrhages and infections were also described.Hypomania was the most frequently reported psychiatric side effect.The relationship between DBS and suicide risk is still controversial and requires further study.Finally,to date,no clear clinical or biological predictors of response can be established,probably because of the differences between studies in terms of the neuroanatomical targets and stimulation protocols assessed.CONCLUSION The present review confirms that DBS is a promising therapy for patients with severe resistant OCD,providing both ST and LT evidence of efficacy.

Cholinergic input from the pedunculopontine nucleus to the cerebellum: implications for deep brain stimulation in Parkinson's disease

Deep brain stimulation（DBS）is a well established electrophysiological treatment initially applied to treat medication-refractory motor symptoms in Parkinson＇s disease（PD）,and is now being explored for several neurological and psychiatric disorders.The specific physiological mechanisms underlying the effectiveness of DBS are not fully understood.

Nursing, Psychological Intervention and Self-Management after Deep Brain Stimulation in Parkinson’s Disease

Parkinson’s disease (PD) is a neurodegenerative disease mainly caused by motor disorders, mostly occurring in middle-aged and elderly people. The incidence of PD has been increasing year by year, and up to now, PD is still an incurable disease. However, more and more data show that early implementation of deep brain stimulation and early medical, psychological, social and other interventions can significantly improve the quality of life and prolong the survival time of patients with Parkinson’s disease (PD). Mental health guidance, cognitive behavioral intervention, psychogenic therapy and scientific nursing for PD patients may improve the functional recovery after Deep Brain Stimulation (DBS) for Parkinson’s disease. This paper discusses the nursing and psychological intervention methods of deep brain stimulation (DBS) implantation in patients with Parkinson’s disease (PD), aiming to scientifically discuss the clinical effect of nursing psychological intervention and improve the quality of life in patients with Parkinson’s disease. Basic nursing and psychological cognitive behavior intervention measures for PD patients can improve the daily activity ability of PD patients, improve the outcome of PD patients, and effectively improve the satisfaction of PD patients with nursing work, which has certain clinical promotion significance.

Deep brain stimulation of the subthalamic nucleus treats Parkinson's disease through enhancing metabolic activity of the corpus striatum Verification by single photon emission computed tomography and positron emission tomography

BACKGROUND： Subthalamic nucleus deep brain stimulation （STN DBS） for Parkinson＇s disease （PD） has achieved good effects, but to date the mechanism of STN DBS remains poorly understood STN DBS may increase dopamine levels or metabolic activity of the corpus striatum. OBJECTIVE： To validate the effects of STN DBS on dopamine metabolism and glucose metabolism in the corpus striatum of hemiparkinsonian monkeys using single photon emission computed tomography （SPECT） and position emission tomography （PET）. DESIGN, TIME AND SET＇rING： A controlled animal study was performed at the Neurosurgery Laboratory, Changhai Hospital of the Second Military Medical University of Chinese PLA between January 2004 and December 2007. METHODS： Hemiparkinsonism was induced in adult Rhesus Macaque monkeys, which exhibit similar characteristics of PD in humans, through unilateral internal carotid artery infusion of 1-methy-4-phenyl-1, 2, 3, 6-tetrahydropyrindine. Following model establishment, stimulation electrodes were implanted in the right STN, and chronic high-frequency stimulation （60 μs pulse width, 130 Hz frequency, and 1.5-2.0 V pressure） was performed. MAIN OUTCOME MEASURES： The changes in dopamine transporter （DAT）, D2 receptor （D2R）, and glucose metabolism in the corpus striatum following STN DBS were observed using SPECT and PET. RESULTS： SPECT examination showed that DAT specific binding in the right corpus striatum was increased at 3 months after DBS compared with prior to stimulation, and D2R specific binding in the right corpus striatum gradually decreased near levels on the left （non-electrode-implanted） side within 3 months after DBS. PET examination showed that the glucose metabolism in the right corpus striatum was markedly increased at 3 months after effective DBS. Hemiparkinsonism monkeys showed improved left limb rigidity, increased activities, and stable gait under chronic high-frequency stimulation. CONCLUSION： STN DBS increased striatal DAT, decreased D2R, and enhanced glucose metabolism, suggesting that chronic, high-frequency STN stimulation enhanced the metabolic activity of the corpus striatum, a mechanism for improving the PD symptoms of hemiparkinsonian monkeys.

Effects of bilateral subthalamic nucleus deep brain stimulation on motor symptoms in Parkinson’s disease: a retrospective cohort study

Deep brain stimulation of the bilateral subthalamic nucleus(STN)is a therapeutic option for patients with Parkinson’s disease(PD)in whom medical therapies have been ineffective.This retrospective cohort study analyzed the motor function of 27 patients with advanced PD,from the First Affiliated Hospital of Guangzhou Medical University,China,who received deep brain stimulation of the bilateral subthalamic nucleus and evaluated its therapeutic effects.The 10-year follow-up data of patients was analyzed in Qingyuan People’s Hospital,Sixth Affiliated Hospital of Guangzhou Medical University,China.The follow-up data were divided into two categories based on patients during levodopa treatment(on-medication)and without levodopa treatment(off-medication).Compared with baseline,the motor function of onmedication PD patients improved after deep brain stimulation of the bilateral subthalamic nucleus.Even 2 years later,the motor function of off-medication PD patients had improved.On-medication PD patients exhibited better therapeutic effects over the 5 years than offmedication PD patients.On-medication patients’akinesia,speech,postural stability,gait,and cognitive function worsened only after 5 years.These results suggest that the motor function of patients with advanced PD benefitted from treatment with deep brain stimulation of the bilateral subthalamic nucleus over a period up to 5 years.The overall therapeutic effects were more pronounced when levodopa treatment was combined with deep brain stimulation of the bilateral subthalamic nucleus.This study was approved by Institutional Review Board of Qingyuan People’s Hospital,The Sixth Affiliated Hospital of Guangzhou Medical University,China(approval No.QPH-IRB-A0140)on January 11,2018.

Towards frequency adaptation for delayed feedback deep brain stimulations

In neurodegenerative disorders such as Parkinson＇s disease （PD）, deep brain stimulation （DBS） is a desirable approach when the medication is less effective for treating the symptoms. DBS incorporates transferring electrical pulses to a specific tissue of the central nervous system, obtaining therapeutic results by modulating the neuronal activity of that region. DBS has certain advantages such as reversibility and adjustability features over medication, since the neuronal firing patterns can be recorded and used to alter the parameters of the DBS signal （Benabid et al., 2009）. One of the DBS indications is its ability to suppress the abnormal neuronal activity to treat symptoms like tremor, akinesia and dystonia.

Parkinsonian oscillations and their suppression by closed-loop deep brain stimulation based on fuzzy concept

This paper provides an adaptive closed-loop strategy for suppressing the pathological oscillations of the basal ganglia based on a variable universe fuzzy algorithm.The pathological basal ganglia oscillations in the theta(4-9 Hz)and beta(12-35 Hz)frequency bands have been demonstrated to be associated with the tremor and rigidity/bradykinesia symptoms in Parkinson’s disease(PD).Although the clinical application of open-loop deep brain stimulation(DBS)is effective,the stimulation waveform with the fixed parameters cannot be self-adjusted as the disease progresses,and thus the stimulation effects go poor.To deal with this difficult problem,a variable universe fuzzy closed-loop strategy is proposed to modulate different PD states.We establish a cortico-basal ganglia-thalamocortical network model to simulate pathological oscillations and test the control effect.The results suggest that the proposed closed-loop control strategy can accommodate the variation of brain states and symptoms,which may become an alternative method to administrate the symptoms in PD.

Forniceal deep brain stimulation in severe Alzheimer's disease:A case report

BACKGROUND Forniceal deep brain stimulation(DBS)has been proposed as an alternative treatment for Alzheimer's disease(AD).Previous studies on mild to moderate AD patients demonstrated improvements in cognitive functions brought about by forniceal DBS.Here,we report our longitudinal findings in one severe AD patient for whom the activities of daily living(ADL)rather than cognitive function significantly improved after 3 mo of continuous stimulation.CASE SUMMARY In 2011,a 62-year-old Chinese male with no previous history of brain injury or other neuropsychological diseases and no family history of dementia developed early symptoms of memory decline and cognitive impairment.Five years later,the symptoms had increased to the extent that they affected his daily living.He lost the ability to work as a businessman and to take care of himself.The patient was given a clinical diagnosis of probable AD and was prescribed donepezil and subsequently memantine,but no improvement in symptoms was observed.The patient then received DBS surgery.After 3 mo of continuous stimulation,the patient's ADL score decreased from 65 points to 47 points,indicating the quality of the patient's daily living improved distinctly.Other scores remained unchanged,suggesting no significant improvement in cognitive function.A follow-up positron emission tomography scan demonstrated perceivable increased glucose metabolism in the classical AD-related brain regions.CONCLUSION Based on this case we hypothesize that forniceal DBS may improve ADL through elevating regional glucose metabolism in the brain.