Clinical Impact of the ABO Blood Type in Patients with Rheumatic Diseases: Is there a Link to the ABO and Rhesus?

OBJECTIVES: Several studies have shown associations of ABO and Rh blood groups with various diseases; however, the relationship of ABO and Rh blood groups with rheumatic diseases are scarce. The aim of the present study was to examine whether there is an association between ABO and Rh blood groups and the types of rheumatic diseases. METHOD: In this multi-centre cross-sectional study, sociodemographic data, type of rheumatic disease, and type ABO and Rh blood groups were examined for patients with different rheumatic diseases. RESULTS: A total of 304 patients; 207 (68.1%) were diagnosed with rheumatoid arthritis, and 40 (13.2%) had systemic lupus erythematosus. The patients were assessed for blood types; 37.8% patients had A type, 27.6% had B type, 19.1% had O type, and 15.4% had AB type. The Rh (+) blood group was more prevalent (89.1%) than Rh (-). Blood group A was more prevalent in patients with rheumatic disease, followed by B, O, and AB respectively, although there was no significant difference in the distribution of ABO groups among rheumatic diseases. Female gender, smoking, and anti-cyclic citrullinated peptide are significantly different between the blood groups within rheumatic diseases. CONCLUSION: The A and Rh (+) blood groups were more commonly observed in patients with rheumatic diseases. There was lack of association between types of rheumatic diseases and ABO blood groups. The study provides knowledge for the interaction between ABO blood groups and several risk factors related to rheumatic diseases and may serve a guide for future clinical studies.

Systemic lupus erythematosus children in Egypt: Homeland spectrum amid the global situation.

OBJECTIVES: This study aims to present the manifestations of juvenile systemic lupus erythematosus (JSLE) across Egypt, to focus on age at onset and gender-driven influence on disease characteristics, and to compare findings to other countries. METHODS: The study included 404 Egyptian children with systemic lupus erythematosus (SLE) presenting to one of the specialized rheumatology centers corresponding to 13 major governorates. Juvenile cases age was ≤ 16°years at the time of recruitment. The SLE Disease Activity Index (SLEDAI) and damage index (DI) were assessed. RESULTS: The mean age was 13.2 ± 2.4°years; 355 females and 49 males (7.2:1), and the disease duration was 2.3 ± 1.6 years, while age at disease onset was 11.1 ± 2.5°years. Their SLEDAI was 13.5 ± 12.3, and DI, 0.36 ± 0.78. The overall estimated prevalence of childhood-SLE patients in the recruited cohort in Egypt was 1/100,000 population (0.24/100000 males and 1.8/100000 females). 7.4% developed pre-pubertal SLE (≤ 7 years); 73.3%, peri-pubertal; and 19.3% during early adolescence. The differences according to age group were equal for gender and clinical manifestations except skin lesions present in 59.3% of pre-pubertal onset, 74.6% of peri-pubertal, and 84.2% of adolescents (p = 0.029), and renal involvement in 73.8% of peripubertal, 62.1% of pre-pubertal and 58.9% of adolescents (p = 0.03). Laboratory investigations, SLEDAI, and DI were similar among age categories. Lupus nephritis was more common in Egypt compared to JSLE from other countries. CONCLUSION: Our large multicenter study identified that female gender influenced disease characteristics with more frequent skin involvement. Skin lesions were significantly higher in adolescents, while renal involvement in peri-pubertal children.

Rheumatology university faculty opinion on coronavirus disease-19 (COVID-19) vaccines: the vaXurvey study from Egypt.

OBJECTIVES: The aim of the present work was to explore the perspectives of Egyptian Rheumatology staff members as regards the coronavirus disease-19 (COVID-19) vaccine. METHODS: The survey is composed of 25 questions. Some questions were adapted from the global rheumatology alliance COVID-19 survey for patients. RESULTS: 187 rheumatology staff members across Egypt from 18 universities and authorizations actively participated with a valid response. The mean time needed to complete the survey was 17.7 ± 13 min. Participants were 159 (85%) females (F:M 5.7:1). One-third agreed that they will be vaccinated once available, 24.6% have already received at least one dose, 29.4% are unsure while 16% will not take it. Furthermore, 70.1% agreed that they will recommend it to the rheumatic diseases (RD) patients once available, 24.1% are not sure while 5.9% will not recommend it. RD priority to be vaccinated against COVID-19 in descending order include SLE (82.9%), RA (55.1%), vasculitis (51.3%), systemic sclerosis (39.6%), MCTD (31.6%), Behcet's disease (28.3%). The most common drugs to be avoided before vaccination included biologics (71.7%), DMARDs (44.4%), biosimilars (26.7%), IVIg (17.1%) and NSAIDs (9.1%). CONCLUSIONS: The results of the study and specifically the low rate of acceptability are alarming to Egyptian health authorities and should stir further interventions to reduce the levels of vaccine hesitancy. As rheumatic disease patients in Egypt were not systematically provided with the vaccine till present, making the vaccine available could as well enhance vaccine acceptance. Further studies to investigate any possible side effects, on a large scale of RD patients are warranted.

Development and validation of a Behçet's Disease Damage Index for adults with BD: An Explicit, Composite and Rated (ECR) tool.

BACKGROUND: Behçet's disease (BD) is a chronic multisystem variable vessel vasculitis. Disease damage is irreversible and permanent. Validated tools evaluating damage are limited. Enhancements in the clinical treatment of vasculitis will take place from the development of refined and exclusive indices for individual vasculitic syndromes including BD and attempting their international validation. OBJECTIVES: This aim was to develop and validate a simple BD Damage Index (BDI). METHODS: This was a nationwide study including 1252 BD patients. The work consisted of 3 stages. Stage 1: items generation for score content. Stage 2: items selection for the draft score was performed by an expert rheumatologist. Stage 3: the content validity of the draft score was assessed and BDI, Vasculitis Damage Index (VDI), Antineutrophil cytoplasmic antibody-associated Vasculitis Index of Damage (AVID) and Combined Damage Assessment Index (CDAI) were calculated and compared. RESULTS: The mean age of the BD patients was 36.1 ± 9.9 years. Stages 1 and 2 resulted in a BDI instrument containing 73 items with a maximum score of 100. Stage 3, the VDI, CDAI, AVID, and BDI were 2.9 ± 2.2, 3.1 ± 2.3, 3.1 ± 2.3 and 5.1 ± 2.9, respectively. High correlations (r = .9) between comparable damage scores assured acceptable concurrent validity. CONCLUSION: The proposed BDI represents a new robust and potentially useful tool when dealing with BD chronic status.

Adult systemic lupus erythematosus in Egypt: The nation-wide spectrum of 3661 patients and world-wide standpoint.

OBJECTIVE: The aim of this study was to present the epidemiology, clinical manifestations and treatment pattern of systemic lupus erythematosus (SLE) in Egyptian patients over the country and compare the findings to large cohorts worldwide. Objectives were extended to focus on the age at onset and gender driven influence on the disease characteristics. PATIENTS AND METHOD: This population-based, multicenter, cross-sectional study included 3661 adult SLE patients from Egyptian rheumatology departments across the nation. Demographic, clinical, and therapeutic data were assessed for all patients. RESULTS: The study included 3661 patients; 3296 females and 365 males (9.03:1) and the median age was 30 years (17-79 years), disease duration 4 years (0-75 years) while the median age at disease onset was 25 years (4-75 years). The overall estimated prevalence of adult SLE in Egypt was 6.1/100,000 population (1.2/100,000 males and 11.3/100,000 females).There were 316 (8.6%) juvenile-onset (Jo-SLE) and 3345 adult-onset (Ao-SLE). Age at onset was highest in South and lowest in Cairo (p < 0.0001). CONCLUSION: SLE in Egypt had a wide variety of clinical and immunological manifestations, with some similarities with that in other nations and differences within the same country. The clinical characteristics, autoantibodies and comorbidities are comparable between Ao-SLE and Jo-SLE. The frequency of various clinical and immunological manifestations varied between gender. Additional studies are needed to determine the underlying factors contributing to gender and age of onset differences.

Impact of COVID-19 pandemic on rheumatoid arthritis from a Multi-Centre patient-reported questionnaire survey: influence of gender, rural-urban gap and north-south gradient.

During the coronavirus disease-2019 (COVID-19) pandemic there were several barriers to treatment access and medication adherence in rheumatoid arthritis (RA) patients. There is no information regarding the RA patient health status in Egypt during the COVID-19. Thus,the aim of this work was to study the impact of the pandemic on RA patients through a patient-reported questionnaire and to determine the influence of gender, geographic regions. This multi-centre study initiated by the Egyptian College of Rheumatology (ECR) was conducted on 1037 RA patients attending rheumatology clinics from 10 governorates. The questionnaire provided covered socio-demographic data, health/disease status, information/knowledge about COVID-19 and medical/family history of the infection. Patients mean age was 44.2 ± 12.3 years;855 females and 182 males; 539(52%) from rural and 497(48%) from urban areas. 41.8% reported a striking difficulty to obtain hydroxychloroquine during the pandemic. The majority (70%) considered maintaining a regular visit to the rheumatologist in addition to remote contact mainly by phone (44.4%) or via WhatsApp (33.1%), in particular among male and urban patients. Urban patients were more likely to be infected by COVID-19 (12.9% vs 6.2%; p < 0.0001) than rural. Northern cities had more patients with suspected COVID-19 (13.9% vs 6.1%; p < 0.0001); was significantly associated with more disease flares (30.8% vs 5.8%) with subsequent change in the RA treatment (20.9% vs 6.4%; p < 0.0001). Patients with RA faced remarkable difficulty to obtain their medications with subsequent change in their disease status. The challenges of the pandemic have hastened changes in the way we deliver health care.

Prognostic role of neurophysiological testing 3-7 days after onset of acute unilateral Bell's palsy.

OBJECTIVE: Recovery from acute Bell's palsy (BP) is variable and there are few predictors of response. We evaluated the usefulness of a range of neurophysiological parameters to predict outcome in BP. METHODS: Fifty-nine patients (age: 33.7±15.4 years) with acute unilateral BP were recruited within 3-7 days of onset. They were evaluated with electroneurography, facial nerve excitability, and the blink reflex. House-Brackmann (HB) clinical scores were obtained at the same time and three months later. All patients received prednisolone treatment and regular rehabilitation. RESULTS: At three months, 41 patients (69.5%) had good recovery, while 18 patients (30.5%) had poor recovery according to the HB scale. The facial nerve excitability threshold and threshold difference between sides were significantly lower in patients with good recovery than those with poor recovery (P values=0.022 and 0.006 respectively). Facial nerve degeneration rate (1 - affected/unaffected amplitude of CMAP of muscle ×100%) recorded in frontalis (P=0.002) and orbicularis oris (P=0.038) were also smaller in good recovery than poor recovery patients. There were no differences in latency and amplitude of CMAPs recorded from frontalis or orbicularis oris muscle, nor in latencies of the components of the blink reflex. ROC analysis showed that patients who had a threshold side difference <13mA (35 cases), had a higher chance of good recovery (85.7% versus 14.3% poor recovery). Patients who had a degeneration rate<50% (38 cases) also had a higher chance of good recovery (78.9%) versus 21.1% who had poor recovery, while patients with a degeneration rate>50% (21 cases) had a 47.8% chance of good recovery versus 52.2% poor recovery (P=0.004). Logistic regression analysis showed that the most significant predictive indicator of BP recovery was the facial nerve degeneration rate of frontalis muscle (P=0.011). CONCLUSION: Facial nerve degeneration rate of frontalis muscle provides the most sensitive prognostic indicator of recovery from acute BP and may provide useful management strategies.

Effects of transcranial direct current stimulation on pain, mood and serum endorphin level in the treatment of fibromyalgia: A double blinded, randomized clinical trial.

BACKGROUND: Recent studies have shown that novel neuro-modulating techniques can have pain-relieving effects in the treatment of chronic pain. The aim of this work is to evaluate the effects of transcranial direct current stimulation (tDCS) in relieving fibromyalgia pain and its relation with beta-endorphin changes. MATERIAL AND METHODS: Forty eligible patients with primary fibromyalgia were randomized to receive real anodal tDCS or sham tDCS of the left motor cortex (M1) daily for 10 days. Each patient was evaluated using widespread pain index (WPI), symptom severity of fibromyalgia (SS), visual analogue scale (VAS), and determination of pain threshold as a primary outcome. Hamilton depression and anxiety scales (HAM-D and HAM-A) and estimation of serum beta-endorphin level pre and post-sessions were used as secondary outcome. All rating scales were conducted at the baseline, after the 5th, 10th session, 15 days and 1 month after the end of the sessions. RESULTS: Eighteen patients from each group completed the follow-up schedule with no significant difference between them regarding the duration of illness or the baseline scales. A significant TIME × GROUP interaction for each rating scale (WPI, SS, VAS, pain threshold, HAM-A, HAM-D) indicated that the effect of treatment differed in the two groups with higher improvement in the experimental scores of the patients in the real tDCS group (P = 0.001 for WPI, SS, VAS, pain threshold, and 0.002, 0.03 for HAM-A, HAM-D respectively). Negative correlations between changes in serum beta-endorphin level and the changes in different rating scales were found (P = 0.003, 0.003, 0.05, 0.002, 0002 for WPI, SS, VAS, HAM-A, and HAM-D respectively). CONCLUSION: Ten sessions of real tDCS over M1 can induce pain relief and mood improvement in patients with fibromyalgia, which were found to be related to changes in serum endorphin levels. ClinicalTrials.gov Identifier: NCT02704611.

High-resolution manometry compared with the University of California, Los Angeles Scleroderma Clinical Trials Consortium GIT 2.0 in Systemic Sclerosis.

OBJECTIVES: To study esophageal high resolution manometry (HRM) in systemic sclerosis (SSc) patients and the correlation of findings to The University of California, Los Angeles Scleroderma Clinical Trials Consortium gastrointestinal tract 2.0 (UCLA SCTC_GIT 2.0). METHODS: Forty SSc patients were administered to the UCLA SCTC GIT 2.0. Patients underwent HRM study (Solar GI MMS). HRM data were compared with 15 healthy volunteers. RESULTS: Forty patients with mean age 46 ± 7 years and disease duration 9.3 ± 7 years reported upper (85.7%), lower GI symptoms (75%), while 5% reported no symptoms. Mean ± SD scores of UCLA SCTC_GIT 2.0 items were as follows: reflux 1.2 ± 0.8, distention 1.6 ± 1.2, fecal soiling 0.3 ± 0.9, diarrhea 0.8 ± 1, social 1 ± 1, emotional 1 ± 1.1, constipation 0.5 ± 0.9, and total GIT score 0.9 ± 0.6. Lower esophageal sphincter (LES) pressure and distal esophageal amplitude were significantly lower in SSc patients than controls. Main manometric findings were decreased LES resting pressure (40%) and aperistalsis (40%). Regression analyses showed distal esophageal amplitude and LES resting pressure negatively correlated with reflux score (r = -0.64; p = 0.001 and r = -0.46; p = 0.019, respectively), and total GIT score (r = -0.54; p = 0.007 and r = -0.42; p = 0.03, respectively). LES resting pressure had negative correlations with diarrhea score (r = -0.062; p = 0.002). CONCLUSIONS: Decreased distal esophageal amplitude encountered as hypoperistalsis or even aperistalsis was associated with increased reflux and GIT scores (negatively correlated) UCLA SCTC_GIT 2.0 questionnaires. The GIT2.0 is easy to use and can serve as an indicator that further testing of the GI tract, including the esophagus, is indicated.

Pulsed Compared to Thermal Radiofrequency to the Medial Calcaneal Nerve for Management of Chronic Refractory Plantar Fasciitis: A Prospective Comparative Study.

BACKGROUND: Radiofrequency (RF) treatment is a minimally invasive procedure that has been used for more than 3 decades in treating various chronic pain syndromes. Conventional (continuous) RF treatment occasionally results in worsening or even initiating a new type of pain. The use of pulsed radiofrequency (PRF), which has a non- or minimally neurodestructive neuromodulatory effect, serves as an alternative to conventional RF therapy in many medical situations. OBJECTIVES: To evaluate the effect of applying PRF for 6 minutes vs. thermal radiofrequency (TRF) for 90 seconds to the medial calcaneal nerve for treatment of chronic refractory plantar fasciitis pain. STUDY DESIGN: Prospective comparative study. SETTING: Pain, Orthopedic, and Rheumatology and Rehabilitation Clinics of Assiut University Hospital. METHODS: Twenty patients with refractory chronic bilateral plantar fasciitis received PRF to the medial calcaneal nerve for 6 minutes for one heel and TRF to the same nerve on the other heel (as their own control) for 90 seconds. Numerical verbal rating scale (NVRS) at waking up from bed and after prolonged walking, and satisfaction score were used for assessment of studied patients at one, 3, 6, 12, and 24 weeks from the intervention. RESULTS: All studied patients showed significant improvement in their pain scale after the intervention that lasted for 24 weeks; however, the PRF heels had significantly better pain scale and satisfaction scores at the first and third weeks assessments when compared to the TRF heels. Effective analgesia was achieved after one week or less after PRF compared to 3 weeks for the TRF (P < 0.001). LIMITATIONS: No randomization. CONCLUSIONS: PRF to the medial calcaneal nerve is a safe and effective method for treatment of chronic plantar fasciitis pain. The onset of effective analgesia can be achieved more rapidly with PRF compared to TRF on the same nerve. Further randomized trials are needed to confirm the therapeutic effect and optimizing the dose of RF needed.Key words: Pulsed radiofrequency, thermal radiofrequency, medial calcaneal nerve, plantar fasciitis, plantar aponeurosis, visual analogue scale.

Post Dural Puncture Headache in Fibromyalgia after Cesarean Section: A Comparative Cohort Study.

BACKGROUND: Patients of chronic pain syndromes like fibromyalgia (FMS) when subjected to spinal anesthesia are theoretically more liable to post dural puncture headache (PDPH) as they have enhanced central nervous system sensitization and decreased descending inhibition. OBJECTIVE: The current study aims to verify the incidence and chronicity of PDPH in FMS patients. STUDY DESIGN: Case control study. METHODS: In a comparative control study, 70 fibromyalgia patients were scheduled for an elective cesarean delivery fibromyalgia group or Group 1. Group 2 included 70 women scheduled for elective cesarean delivery who had no history of chronic pain and is used as a control group. Both groups were compared regarding the incidence of development of PDPH in the first postoperative 48 hours and the persistence of PDPH for 7 days or more. SETTINGS: Women's Health Hospital, Assiut University, antenatal Clinic. RESULTS: The fibromyalgia group reported more PDPH (18 patients, 25.7%) as compared to the control group (10 patients, 14.3%), P < 0.01. PDPH persisted for 7 or more days in 8 patients in the fibromyalgia group (11.4%) while, it persisted in 2.86% of the control patients. PDPH continued for more than 3 months in 2 patients in the fibromyalgia group (2.86%). LIMITATIONS: Difficulty in calculating the dose of analgesics as patients with fibromyalgia may use other analgesics due to musculoskeletal pain. CONCLUSION: Dural puncture increases the incidence of PDPH in fibromyalgia patients in comparison with normal controls without increasing other postoperative side effects.

A double-blind randomized clinical trial on the efficacy of magnetic sacral root stimulation for the treatment of Monosymptomatic Nocturnal Enuresis.

PURPOSE: Purpose of this study was to evaluate the long term efficacy of repetitive sacral root magnetic stimulation (rSMS) in patients with monosymptomatic nocturnal enuresis (MNE). METHODS: Forty four patients were randomized to receive either sham or real repetitive sacral root magnetic stimulation (rSMS; 15 Hz with a total of 1500 pulses/session) for 10 sessions. Evaluation was performed before starting treatment, immediately after the 5th and 10th treatment session, and 1 month later, using frequency of enuresis/week, visual analogue scale (VAS) and quality of life as outcome measures. Resting and active motor thresholds of gastrocnemius muscles were measured before and after the end of sessions. RESULTS: Both treatment and control groups were comparable for baseline measures of frequency of enuresis, and VAS. The mean number of wet nights/week was significantly reduced in patients who received real rSMS. This improvement was maintained 1 month after the end of treatment. Patients receiving real-rSMS also reported an improvement in VAS ratings and quality of life. A significant reduction of resting motor threshold was recorded after rSMS in the real group while no such changes were observed in the sham group. CONCLUSION: These findings suggest that rSMS has potential as an adjuvant treatment for MNE and deserves further study.

Dual-hemisphere repetitive transcranial magnetic stimulation for rehabilitation of poststroke aphasia: a randomized, double-blind clinical trial.

BACKGROUND: Recent neuroimaging studies on poststroke aphasia revealed maladaptive cortical changes in both hemispheres, yet their functional contribution in language recovery remains elusive. The aim of this study was to evaluate the long-term efficacy of dual-hemisphere repetitive transcranial magnetic stimulation (rTMS) on poststroke aphasia. METHODS: Thirty patients with subacute poststroke nonfluent aphasia were randomly allocated to receive real or sham rTMS. Each patient received 1000 rTMS pulses (1 Hz at 110% of resting motor threshold [rMT] over the right unaffected Broca's area and 1000 pulses (20 Hz at 80% rMT) over the left affected Broca's area for 10 consecutive days followed by speech/language training. The language section of the Hemispheric Stroke Scale (HSS), the Stroke Aphasic Depression Questionnaire-Hospital Version (SADQ-H), and the National Institutes of Health Stroke Scale (NIHSS) were measured before, immediately after the 10 sessions, and 1 and 2 months after the last session. RESULTS: At baseline, there were no significant differences between groups in demographic and clinical rating scales. However, there was a significantly greater improvement in the HSS language score as well as in the SADQ-H after real rTMS compared with sham rTMS, which remained significant 2 months after the end of the treatment sessions. CONCLUSION: This is the first clinical study of dual-hemisphere rTMS in poststroke aphasia. Combining dual-hemisphere rTMS with language training might be a feasible treatment for nonfluent aphasia; further multicenter studies are needed to confirm this result.

Effect of anodal versus cathodal transcranial direct current stimulation on stroke rehabilitation: a pilot randomized controlled trial.

OBJECTIVE: We compared the long-term effect of anodal versus cathodal transcranial direct current stimulation (tDCS) on motor recovery in patients after subacute stroke. METHODS: Forty patients with ischemic stroke undergoing rehabilitation were randomly assigned to 1 of 3 groups: Anodal, Cathodal (over-affected and unaffected hemisphere, respectively), and Sham. Each group received tDCS at an intensity of 2 mA for 25 minutes daily for 6 consecutive days over of the motor cortex hand area. Patients were assessed with the National Institutes of Health Stroke Scale (NIHSS), Orgogozo's MCA scale (OMCASS), the Barthel index (BI), and the Medical Research Council (MRC) muscle strength scale at baseline, after the sixth tDCS session and then 1, 2, and 3 months later. Motor cortical excitability was measured with transcranial magnetic stimulation (TMS) at baseline and after the sixth session. RESULTS: By the 3-month follow-up, all groups had improved on all scales with P values ranging from .01 to .0001. Improvement was equal in the Anodal and Cathodal groups. When these treated groups were combined and compared with Sham, significant interactions were seen for the OMCASS and BI scales of functional ability (P = .002 for each). There was increased cortical excitability of the affected hemisphere in all groups with the changes being greater in the real versus sham groups. There were borderline significant improvements in muscle strength. CONCLUSION: A brief course of 2 types of tDCS stimulation is superior to sham stimulation in enhancing the effect of rehabilitation training to improve motor recovery after stroke.

Repetitive lumbosacral nerve magnetic stimulation improves bladder dysfunction due to lumbosacral nerve injury: a pilot randomized controlled study.

BACKGROUND: Rapid rate magnetic stimulation of human sacral nerve roots can reduce stress incontinence. OBJECTIVE: To test stimulation for urgency incontinence due to lumbosacral plexopathy. METHODS: The authors studied patients with intractable neurogenic urinary dysfunction due to lumbosacral nerve injuries. Eligible patients were randomized to receive either real or sham repetitive lumbosacral magnetic stimulation (rLMS; 15 Hz with a total of 1500 pulses/session) for 10 sessions. Evaluation was performed before starting treatment, immediately after the 5th and 10th treatment session, and 1 month later, using rating scales to score urinary dysfunction and a visual analogue scale (VAS) to assess lower back pain. Posterior tibial nerve F-wave and H-reflexes were tested before and after treatment. RESULTS: Both treatment and control groups were comparable for baseline characters and sphincteric disturbances. The mean number of voids and incontinence per 24 hours was significantly reduced in patients who received rLMS. The improvement was maintained 1 month after the end of treatment. Patients receiving real-rLMS also reported an improvement in VAS ratings. Improvement in F-wave and H-reflex latencies after real stimulation (P = .002 and P = .036, respectively) was found as well. CONCLUSION: rLMS at 15 Hz may improve urinary dysfunction secondary to lumbosacral nerve injury. Further trials can determine the profile of patients who may benefit and optimal stimulation parameters.