Pediatric and Adult Brain Death/Death by Neurologic Criteria Consensus Guideline.

BACKGROUND AND OBJECTIVES: The purpose of this guideline is to update the 2010 American Academy of Neurology (AAN) brain death/death by neurologic criteria (BD/DNC) guideline for adults and the 2011 American Academy of Pediatrics, Child Neurology Society, and Society of Critical Care Medicine guideline for infants and children and to clarify the BD/DNC determination process by integrating guidance for adults and children into a single guideline. Updates in this guideline include guidance related to conducting the BD/DNC evaluation in the context of extracorporeal membrane oxygenation, targeted temperature management, and primary infratentorial injury. METHODS: A panel of experts from multiple medical societies developed BD/DNC recommendations. Because of the lack of high-quality evidence on the subject, a novel, evidence-informed formal consensus process was used. This process relied on the panel experts' review and detailed knowledge of the literature surrounding BD/DNC to guide the development of preliminary recommendations. Recommendations were formulated and voted on, using a modified Delphi process, according to the 2017 AAN Clinical Practice Guideline Process Manual. MAJOR RECOMMENDATIONS: Eighty-five recommendations were developed on the following: (1) general principles for the BD/DNC evaluation, (2) qualifications to perform BD/DNC evaluations, (3) prerequisites for BD/DNC determination, (4) components of the BD/DNC neurologic examination, (5) apnea testing as part of the BD/DNC evaluation, (6) ancillary testing as part of the BD/DNC evaluation, and (7) special considerations for BD/DNC determination.

Stroke Prevention in Symptomatic Large Artery Intracranial Atherosclerosis Practice Advisory: Report of the AAN Guideline Subcommittee.

BACKGROUND AND OBJECTIVES: To review treatments for reducing the risk of recurrent stroke or death in patients with symptomatic intracranial atherosclerotic arterial stenosis (sICAS). METHODS: The development of this practice advisory followed the process outlined in the American Academy of Neurology Clinical Practice Guideline Process Manual, 2011 Edition, as amended. The systematic review included studies through November 2020. Recommendations were based on evidence, related evidence, principles of care, and inferences. MAJOR RECOMMENDATIONS: Clinicians should recommend aspirin 325 mg/d for long-term prevention of stroke and death and should recommend adding clopidogrel 75 mg/d to aspirin for up to 90 days to further reduce stroke risk in patients with severe (70%-99%) sICAS who have low risk of hemorrhagic transformation. Clinicians should recommend high-intensity statin therapy to achieve a goal low-density lipoprotein cholesterol level <70 mg/dL, a long-term blood pressure target of <140/90 mm Hg, at least moderate physical activity, and treatment of other modifiable vascular risk factors for patients with sICAS. Clinicians should not recommend percutaneous transluminal angioplasty and stenting for stroke prevention in patients with moderate (50%-69%) sICAS or as the initial treatment for stroke prevention in patients with severe sICAS. Clinicians should not routinely recommend angioplasty alone or indirect bypass for stroke prevention in patients with sICAS outside clinical trials. Clinicians should not recommend direct bypass for stroke prevention in patients with sICAS. Clinicians should counsel patients about the risks of percutaneous transluminal angioplasty and stenting and alternative treatments if one of these procedures is being contemplated.

Cognitive Testing During Mild Acute Ischemic Stroke Predicts Long-Term Return to Work.

OBJECTIVES: Many survivors of a mild ischemic stroke do not return to work or driving. Cognitive testing is commonly done to assess long-term cognitive impairment after stroke. Inpatient cognitive testing during the acute period of ischemic stroke may also be a predictor for workforce reengagement and functional outcome. MATERIALS AND METHODS: At our comprehensive stroke center, we prospectively enrolled previously working adults < 65 years old who were diagnosed with first-ever ischemic stroke, had a prestroke modified Rankin Scale (mRS) ≤ 1 and NIHSS ≤ 3. Testing performed within 1 week of stroke included the Montreal Cognitive Assessment (MOCA), Clock Drawing Test (CDT), Trail Making Tests A and B, Backward Digit Span Test, and Hospital Anxiety and Depression Scale (HADS). Other data obtained included age, gender, years of education, occupation, stroke location, stroke laterality, and presence of white matter disease on imaging. Outcome measures assessed at 3 months, 6 months, and 12 months post-stroke included return to work, return to driving, and mRS. In a logistic regression analysis, we performed both univariate and multivariate analyses. Multivariate analysis was completed on variables with p-value ≤ 0.05 in the univariate analysis. RESULTS: Of 39 total stroke patients enrolled and tested (median [IQR] age 55 [46-60] years; 77.5% male; 22.5% female), 36 completed 3-month follow up, of which 58% returned to work, 78% returned to driving, and 72% had mRS of 0-1. In multivariate analysis, a single point increase in the clock drawing task score increased the odds of return to work by 3.79 (95% CI, 1.10-14.14) and return to driving by 6.74 (95% CI, 1.22-37.23) at 3 months. MOCA and HADS were both associated with mRS ≤ 1. MOCA was associated with return to work at 6 months and CDT was associated with return to work at 12 months. CONCLUSION: Cognitive testing with CDT and MOCA in the acute period after ischemic stroke may predict common patient goals post stroke, including return to work, driving, and independence. These tools can potentially be used for prognosis and identifying those who may benefit from further interventions.

A Disclosure About Death Disclosure: Variability in Circulatory Death Determination.

INTRODUCTION: Circulatory-respiratory death declaration is a common duty of physicians, but little is known about the amount of education and physician practice patterns in completing this examination. METHODS: An online survey of physicians was conducted evaluating the rate of formal training and specific examination techniques used in the pronouncement of circulatory-respiratory death. Data, including the level of practice, training received in a formal death declaration, and examination components, were collected. RESULTS: Respondents were attending physicians (52.4%), residents (30.2%), fellows (10.7%), and interns (6.7%). Most respondents indicated they had received no formal training in death pronouncement; however, most reported self-perceived competence. When comparing examination components used by the study's cohort, 95 different examination combinations were used for death pronouncement. CONCLUSIONS: Formal training in death pronouncement was uncommon and clinical practice varied. Implementation of formal training and standardization of the examination are necessary to improve physician competence and reliability in death declarations.

Diagnostic Yield of TEE in Patients with Cryptogenic Stroke and TIA with Normal TTE: A Systematic Review and Meta-Analysis.

INTRODUCTION: The role of transesophageal echocardiography (TEE) in cryptogenic stroke and transient ischemic attack (TIA) with normal transthoracic echocardiography (TTE) remains controversial in the absence of definite guidelines. We aimed to perform a systematic review and meta-analysis to estimate an additional diagnostic yield and clinical impact of TEE in patients with cryptogenic stroke and TIA with normal TTE. METHODS: We performed a systematic review of cohort studies on PubMed using the keywords 'cryptogenic stroke', cryptogenic TIA', 'TEE', and 'TTE' with matching MeSH terms. We included studies with patients who had cryptogenic stroke or TIA and had normal TTE findings, where the study intended to obtain TEE on all patients and reported all TEE abnormalities. The studies containing patients with atrial fibrillation were excluded. All studies were evaluated for internal and external validity. Inverse variance random effects models were used to calculate the effect size, the number needed to diagnose, and the 95% confidence interval. RESULTS: We included 15 studies with 2054 patients and found LA/LAA/aortic thrombus, valvular vegetation, PFO-ASA, valvular abnormalities, and complex aortic plaques on TEE. Of these, 37.5% (29.7%-45.1%) of patients had additional cardiac findings on TEE. Management of 13.6% (8.1%-19.1%) of patients had changed after TEE evaluation. Based on current guidelines, it should change management in 4.1% (2.1%-6.2%) of patients and could potentially change management in 30.4% (21.9%-38.9%) of patients. Sensitivity analysis was also performed with only class II studies to increase internal validity, which showed additional cardiac findings in 38.4% (28.5%-48.3%), changed management in 20.2% (8.7%-31.8%), should change management in 4.7% (1.5%-7.9%), and could potentially change management in 30.4% (17.8%-43.0%) of patients. CONCLUSIONS: The diagnostic yield of TEE to find any additional cardiac findings in patients with cryptogenic stroke or TIA is not only high, but it can also change management for certain cardiac abnormalities. TTE in cryptogenic stroke or TIA may mitigate future risks by tailoring the management of these patients.

Practice advisory update summary: Patent foramen ovale and secondary stroke prevention: Report of the Guideline Subcommittee of the American Academy of Neurology.

OBJECTIVE: To update the 2016 American Academy of Neurology (AAN) practice advisory for patients with stroke and patent foramen ovale (PFO). METHODS: The guideline panel followed the AAN 2017 guideline development process to systematically review studies published through December 2017 and formulate recommendations. MAJOR RECOMMENDATIONS: In patients being considered for PFO closure, clinicians should ensure that an appropriately thorough evaluation has been performed to rule out alternative mechanisms of stroke (level B). In patients with a higher risk alternative mechanism of stroke identified, clinicians should not routinely recommend PFO closure (level B). Clinicians should counsel patients that having a PFO is common; that it occurs in about 1 in 4 adults in the general population; that it is difficult to determine with certainty whether their PFO caused their stroke; and that PFO closure probably reduces recurrent stroke risk in select patients (level B). In patients younger than 60 years with a PFO and embolic-appearing infarct and no other mechanism of stroke identified, clinicians may recommend closure following a discussion of potential benefits (absolute recurrent stroke risk reduction of 3.4% at 5 years) and risks (periprocedural complication rate of 3.9% and increased absolute rate of non-periprocedural atrial fibrillation of 0.33% per year) (level C). In patients who opt to receive medical therapy alone without PFO closure, clinicians may recommend an antiplatelet medication such as aspirin or anticoagulation (level C).

Practice advisory: Thymectomy for myasthenia gravis (practice parameter update): Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology.

OBJECTIVE: To review updated evidence regarding the effectiveness of thymectomy for treating patients with myasthenia gravis (MG). METHODS: The practice advisory panel performed a systematic review and developed practice recommendations using methods developed by the American Academy of Neurology. RESULTS: One Class I study of patients younger than 65 years with nonthymomatous acetylcholine receptor antibody-positive (AChR ab+) generalized MG demonstrated better clinical outcomes in patients treated with oral prednisone and undergoing thymectomy compared with patients treated with prednisone alone, including an increased probability of attaining minimal manifestation status (no symptoms or functional limitations). CONCLUSION: For patients with nonthymomatous AChR ab+ generalized MG, treatment with thymectomy plus prednisone is probably more effective than treatment with prednisone alone for increasing the chance of attaining minimal manifestation status (risk difference at 36 months, 20%; 95% confidence interval, 1.6%-37%; moderate confidence in the evidence). RECOMMENDATIONS: Clinicians should discuss thymectomy treatment with patients with AChR ab+ generalized MG (Level B). Clinicians should counsel patients with AChR ab+ generalized MG considering minimally invasive thymectomy techniques that it is uncertain whether the benefit attained by extended transsternal thymectomy will also be attained by minimally invasive approaches (Level B).

Evaluator Agreement in Medical Student Assessment Across a Multi-Campus Medical School During a Standardized Patient Encounter.

PURPOSE: Class rank and clerkship grades impact a medical student's residency application. The variability and inter-rater reliability in assessment across multiple clinical sites within a single university system is unknown. We aimed to determine if medical student assessment across medical school campuses is consistent when using a standardized scoring rubric. DESIGN/METHODS: Attending physicians who participate in assignment of clerkship grades for neurology from three separate clinical campuses of the same medical school observed 10 identical standardized patient encounters completed by third year medical students during the 2017-2018 academic year. Scoring was completed using a standardized rubric. Descriptive analysis and intra-rater comparisons were completed. Evaluations as a part of this study were completed in 2018. RESULTS: Of 50 possible points for the patient encounter, the median score among all medical students and all evaluators was 43 (IQR 40, 45.5). Evaluator number 1 provided a statistically significant lower overall score as compared to evaluators 2 and 3 (p = 0.0001 and p = 0.0006, respectively), who were consistently similar in their overall medical student assessment (p = 0.46). Overall agreement between evaluators was good (ICC = 0.805, 95% CI 0.36-0.95) and consistency was excellent (ICC = 0.91, 95% CI 0.75-0.97). CONCLUSIONS: Medical student evaluation across multiple clinical campus sites via observation of identical standardized patient encounters and use of a standardized scoring rubric generally demonstrated good inter-rater agreement and consistency, but the small variation seen may affect overall clerkship scores.

Participation and consultation engagement strategies have complementary roles: A case study of patient and public involvement in clinical practice guideline development.

BACKGROUND: Patient and public involvement (PPI) is recommended when developing high-quality clinical practice guidelines, but the effects of different PPI strategies are largely unstudied. OBJECTIVE: To assess the impact of participation and consultation strategies on guideline question development. DESIGN: Instrumental case study design. SETTING AND PARTICIPANTS: This study used a clinical practice guideline in development by the American Academy of Neurology. A patient, two caregivers and a dementia advocate participated in the guideline development group alongside clinicians. The guideline protocol was posted for public consultation for 30 days. INTERVENTIONS STUDIED: Participation (patient representatives on the guideline development group) and consultation (public comment, survey) PPI strategies. MAIN OUTCOME MEASURES: Public comment responses and guideline development group meeting transcripts were analysed descriptively. Transcript quotes were compared to the conceptual model of PPI in guideline development. The effects of participation and consultation strategies within the guideline case were compared. RESULTS: Participation strategies shaped discussions, set a patient-centred scope, highlighted personal aspects of disease, affected how professionals viewed PPI, identified issues overlooked by medical professionals, and contributed to selecting patient-relevant guideline populations and outcomes. Professionals responded to public comment more than patient representatives. Patient survey participants confirmed the priorities voiced by patient representatives on the guideline development group. Final guideline questions included populations and outcomes promoted by patient representatives despite negative feedback from professional public commenters. DISCUSSION AND CONCLUSIONS: Participation and consultation PPI strategies have different advantages. Congruence between strategies increases the strength of the patient voice. Guideline developers should prioritize using both strategies for successful PPI.

Case-Control Study of Cephalometrics in Patients with Moyamoya.

OBJECTIVE: To determine whether cranial metrics consistently differed between patients with moyamoya and age-, sex-, and race-matched controls. METHODS: Patients diagnosed with moyamoya disease by cerebral angiogram were obtained from a prospectively collected database through the Department of Neurosurgery at the University of Kansas Medical Center. Control patients matched by decade of age, sex, and race were collected through a deidentified hospital database by International Classification of Diseases-9 and 10 codes for ischemic stroke to identify patients with computed tomography angiograms. Imaging studies for both groups were analyzed to obtain 6 skull metrics: maximum anterior to posterior distance, maximum biparietal distance, bregma to occiput distance, right carotid canal diameter (CCD), left CCD, and cephalic index. RESULTS: Forty-five patients were identified in each cohort. Measurements of mean anterior to posterior skull diameter, mean biparietal skull diameter, bregma to occiput distances, and calculated cephalic index did not demonstrate a statistically significant difference between patients with moyamoya and control patients. Right carotid canal mean diameter was 4.8 mm for the moyamoya group and 5.4 mm for the control group, with a significant raw mean difference of -0.61 mm (95% confidence interval, -0.95 to -0.27). Left CCD was 4.7 mm for the moyamoya group and 5.5 mm for the control group, resulting in a significant raw mean difference of -0.76 mm (95% confidence interval, -1.09 to -0.43). CONCLUSIONS: This study identified 2 skull parameters as statistically different in patients with moyamoya compared with a matched control group of patients with ischemic stroke: right CCD and left CCD.

Patient Stakeholder Versus Physician Preferences Regarding Amyloid PET Testing.

BACKGROUND: Patient and caregiver perspectives on amyloid positron emission tomography (PET) use are largely unexplored, particularly as compared with clinician views. METHODS: We surveyed clinicians, patients, caregivers, and dementia advocates on topics relating to an evidence-based guideline on amyloid PET use. Topic importance was rated on a 9-point scale. Patient stakeholder and clinician views were compared using the Mann-Whitney U test. RESULTS: Patient representatives (n=107) rated all survey topics as equal to or more important than clinicians (n=114) except 1 item discussing potential harms of false-positive diagnoses. Differences between patient representative and clinician populations were greatest when comparing the competing values of false-positive and false-negative diagnoses and the value of testing asymptomatic individuals. CONCLUSIONS: Patients and caregivers emphasized the importance of having a dementia diagnosis and placed more value on testing and outcomes for asymptomatic populations than clinicians. This underscores the importance of research investigating the effect of amyloid PET results on asymptomatic individuals and the need for amyloid PET ordering and disclosure standards.

Variability in reported physician practices for brain death determination.

OBJECTIVES: The degree of training and variability in the clinical brain death examination performed by physicians is not known. METHODS: Surveys were distributed to physicians (including physicians-in-training) practicing at 3 separate academic medical centers. Data, including level of practice, training received in completion of a brain death examination, examination components performed, and use of confirmatory tests were collected. Data were evaluated for accuracy in the brain death examination, self-perceived competence in the examination, and indications for confirmatory tests. RESULTS: Of 225 total respondents, 68 reported completing brain death examinations in practice. Most physicians who complete a brain death examination reported they had received training in how to complete the examination (76.1%). Seventeen respondents (25%) reported doing a brain death examination that is consistent with the current practice guideline. As a part of their brain death assessment, 10.3% of physicians did not report completing an apnea test. Of clinicians who obtain confirmatory tests on an as-needed basis, 28.3% do so if a patient breathes during an apnea test, a clinical finding that is not consistent with brain death. CONCLUSIONS: There is substantial variability in how physicians approach the adult brain death examination, but our survey also identified lack of training in nearly 1 in 4 academic physicians. A formal training course in the principles and proper technique of the brain death examination by physicians with expert knowledge of this clinical assessment is recommended.

Practice Guideline Update Recommendations Summary: Disorders of Consciousness: Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology; the American Congress of Rehabilitation Medicine; and the National Institute on Disability, Independent Living, and Rehabilitation Research.

OBJECTIVE: To update the 1995 American Academy of Neurology (AAN) practice parameter on persistent vegetative state and the 2002 case definition on minimally conscious state (MCS) and provide care recommendations for patients with prolonged disorders of consciousness (DoC). METHODS: Recommendations were based on systematic review evidence, related evidence, care principles, and inferences using a modified Delphi consensus process according to the AAN 2011 process manual, as amended. RECOMMENDATIONS: Clinicians should identify and treat confounding conditions, optimize arousal, and perform serial standardized assessments to improve diagnostic accuracy in adults and children with prolonged DoC (Level B). Clinicians should counsel families that for adults, MCS (vs vegetative state [VS]/ unresponsive wakefulness syndrome [UWS]) and traumatic (vs nontraumatic) etiology are associated with more favorable outcomes (Level B). When prognosis is poor, long-term care must be discussed (Level A), acknowledging that prognosis is not universally poor (Level B). Structural MRI, SPECT, and the Coma Recovery Scale-Revised can assist prognostication in adults (Level B); no tests are shown to improve prognostic accuracy in children. Pain always should be assessed and treated (Level B) and evidence supporting treatment approaches discussed (Level B). Clinicians should prescribe amantadine (100-200 mg bid) for adults with traumatic VS/UWS or MCS (4-16 weeks post injury) to hasten functional recovery and reduce disability early in recovery (Level B). Family counseling concerning children should acknowledge that natural history of recovery, prognosis, and treatment are not established (Level B). Recent evidence indicates that the term chronic VS/UWS should replace permanent VS, with duration specified (Level B). Additional recommendations are included.

Comprehensive Systematic Review Update Summary: Disorders of Consciousness: Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology; the American Congress of Rehabilitation Medicine; and the National Institute on Disability, Independent Living, and Rehabilitation Research.

OBJECTIVE: To update the 1995 American Academy of Neurology (AAN) practice parameter on persistent vegetative state and the 2002 case definition for the minimally conscious state (MCS) by reviewing the literature on the diagnosis, natural history, prognosis, and treatment of disorders of consciousness lasting at least 28 days. METHODS: Articles were classified per the AAN evidence-based classification system. Evidence synthesis occurred through a modified Grading of Recommendations Assessment, Development and Evaluation process. Recommendations were based on evidence, related evidence, care principles, and inferences according to the AAN 2011 process manual, as amended. RESULTS: No diagnostic assessment procedure had moderate or strong evidence for use. It is possible that a positive EMG response to command, EEG reactivity to sensory stimuli, laser-evoked potentials, and the Perturbational Complexity Index can distinguish MCS from vegetative state/unresponsive wakefulness syndrome (VS/UWS). The natural history of recovery from prolonged VS/UWS is better in traumatic than nontraumatic cases. MCS is generally associated with a better prognosis than VS (conclusions of low to moderate confidence in adult populations), and traumatic injury is generally associated with a better prognosis than nontraumatic injury (conclusions of low to moderate confidence in adult and pediatric populations). Findings concerning other prognostic features are stratified by etiology of injury (traumatic vs nontraumatic) and diagnosis (VS/UWS vs MCS) with low to moderate degrees of confidence. Therapeutic evidence is sparse. Amantadine probably hastens functional recovery in patients with MCS or VS/UWS secondary to severe traumatic brain injury over 4 weeks of treatment. Recommendations are presented separately.

Comprehensive systematic review update summary: Disorders of consciousness: Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology; the American Congress of Rehabilitation Medicine; and the National Institute on Disability, Independent Living, and Rehabilitation Research.

OBJECTIVE: To update the 1995 American Academy of Neurology (AAN) practice parameter on persistent vegetative state and the 2002 case definition for the minimally conscious state (MCS) by reviewing the literature on the diagnosis, natural history, prognosis, and treatment of disorders of consciousness lasting at least 28 days. METHODS: Articles were classified per the AAN evidence-based classification system. Evidence synthesis occurred through a modified Grading of Recommendations Assessment, Development and Evaluation process. Recommendations were based on evidence, related evidence, care principles, and inferences according to the AAN 2011 process manual, as amended. RESULTS: No diagnostic assessment procedure had moderate or strong evidence for use. It is possible that a positive EMG response to command, EEG reactivity to sensory stimuli, laser-evoked potentials, and the Perturbational Complexity Index can distinguish MCS from vegetative state/unresponsive wakefulness syndrome (VS/UWS). The natural history of recovery from prolonged VS/UWS is better in traumatic than nontraumatic cases. MCS is generally associated with a better prognosis than VS (conclusions of low to moderate confidence in adult populations), and traumatic injury is generally associated with a better prognosis than nontraumatic injury (conclusions of low to moderate confidence in adult and pediatric populations). Findings concerning other prognostic features are stratified by etiology of injury (traumatic vs nontraumatic) and diagnosis (VS/UWS vs MCS) with low to moderate degrees of confidence. Therapeutic evidence is sparse. Amantadine probably hastens functional recovery in patients with MCS or VS/UWS secondary to severe traumatic brain injury over 4 weeks of treatment. Recommendations are presented separately.

Practice guideline update recommendations summary: Disorders of consciousness: Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology; the American Congress of Rehabilitation Medicine; and the National Institute on Disability, Independent Living, and Rehabilitation Research.

OBJECTIVE: To update the 1995 American Academy of Neurology (AAN) practice parameter on persistent vegetative state and the 2002 case definition on minimally conscious state (MCS) and provide care recommendations for patients with prolonged disorders of consciousness (DoC). METHODS: Recommendations were based on systematic review evidence, related evidence, care principles, and inferences using a modified Delphi consensus process according to the AAN 2011 process manual, as amended. RECOMMENDATIONS: Clinicians should identify and treat confounding conditions, optimize arousal, and perform serial standardized assessments to improve diagnostic accuracy in adults and children with prolonged DoC (Level B). Clinicians should counsel families that for adults, MCS (vs vegetative state [VS]/unresponsive wakefulness syndrome [UWS]) and traumatic (vs nontraumatic) etiology are associated with more favorable outcomes (Level B). When prognosis is poor, long-term care must be discussed (Level A), acknowledging that prognosis is not universally poor (Level B). Structural MRI, SPECT, and the Coma Recovery Scale-Revised can assist prognostication in adults (Level B); no tests are shown to improve prognostic accuracy in children. Pain always should be assessed and treated (Level B) and evidence supporting treatment approaches discussed (Level B). Clinicians should prescribe amantadine (100-200 mg bid) for adults with traumatic VS/UWS or MCS (4-16 weeks post injury) to hasten functional recovery and reduce disability early in recovery (Level B). Family counseling concerning children should acknowledge that natural history of recovery, prognosis, and treatment are not established (Level B). Recent evidence indicates that the term chronic VS/UWS should replace permanent VS, with duration specified (Level B). Additional recommendations are included.