Validity of the modified Rankin Scale in patients with aneurysmal subarachnoid hemorrhage: a randomized study.

PURPOSE: The modified Rankin Scale (mRS), a clinician-reported outcome measure of global disability, has never been validated in patients with aneurysmal subarachnoid hemorrhage (aSAH). The aims of this study are to assess: (1) convergent validity of the mRS; (2) responsiveness of the mRS; and (3) the distribution of mRS scores across patient-reported outcome measures (PROMs). METHODS: This is a prospective randomized multicenter study. The mRS was scored by a physician for all patients, and subsequently by structured interview for half of the patients and by self-assessment for the other half. All patients completed EuroQoL 5D-5L, RAND-36, Stroke Specific Quality of Life scale (SS-QoL) and Global Perceived Effect (GPE) questionnaires. Convergent validity and responsiveness were assessed by testing hypotheses. RESULTS: In total, 149 patients with aSAH were included for analysis. The correlation of the mRS with EQ-5D-5L was r = - 0.546, while with RAND-36 physical and mental component scores the correlation was r = - 0.439and r = - 0.574 respectively, and with SS-QoL it was r = - 0.671. Three out of four hypotheses for convergent validity were met. The mRS assessed through structured interviews was more highly correlated with the mental component score than with the physical component score of RAND-36. Improvement in terms of GPE was indicated by 83% of patients; the mean change score of these patients on the mRS was - 0.08 (SD 0.915). None of the hypotheses for responsiveness were met. CONCLUSION: The results show that the mRS generally correlates with other instruments, as expected, but it lacks responsiveness. A structured interview of the mRS is best for detecting disabling neuropsychological complaints. REGISTRATION: URL: https://trialsearch.who.int ; Unique identifier: NL7859, Date of first administration: 08-07-2019.

Inter-method reliability of the modified Rankin Scale in patients with subarachnoid hemorrhage.

BACKGROUND AND OBJECTIVES: The modified Rankin Scale (mRS) is one of the most frequently used outcome measures in trials in patients with an aneurysmal subarachnoid hemorrhage (aSAH). The assessment method of the mRS is often not clearly described in trials, while the method used might influence the mRS score. The aim of this study is to evaluate the inter-method reliability of different assessment methods of the mRS. METHODS: This is a prospective, randomized, multicenter study with follow-up at 6 weeks and 6 months. Patients aged ≥ 18 years with aSAH were randomized to either a structured interview or a self-assessment of the mRS. Patients were seen by a physician who assigned an mRS score, followed by either the structured interview or the self-assessment. Inter-method reliability was assessed with the quadratic weighted kappa score and percentage of agreement. Assessment of feasibility of the self-assessment was done by a feasibility questionnaire. RESULTS: The quadratic weighted kappa was 0.60 between the assessment of the physician and structured interview and 0.56 between assessment of the physician and self-assessment. Percentage agreement was, respectively, 50.8 and 19.6%. The assessment of the mRS through a structured interview and by self-assessment resulted in systematically higher mRS scores than the mRS scored by the physician. Self-assessment of the mRS was proven feasible. DISCUSSION: The mRS scores obtained with different assessment methods differ significantly. The agreement between the scores is low, although the reliability between the assessment methods is good. This should be considered when using the mRS in clinical trials. TRIAL REGISTRATION: www.trialregister.nl ; Unique identifier: NL7859.

The influence of depth of anesthesia and blood pressure on muscle recorded motor evoked potentials in spinal surgery. A prospective observational study protocol.

For high-risk spinal surgeries, intraoperative neurophysiological monitoring (IONM) is used to detect and prevent intraoperative neurological injury. The motor tracts are monitored by recording and analyzing muscle transcranial electrical stimulation motor evoked potentials (mTc-MEPs). A mTc-MEP amplitude decrease of 50-80% is the most common warning criterion for possible neurological injury. However, these warning criteria often result in false positive warnings. False positives may be caused by inadequate depth of anesthesia and blood pressure on mTc-MEP amplitudes. The aim of this paper is to validate the study protocol in which the goal is to investigate the effects of depth of anesthesia (part 1) and blood pressure (part 2) on mTc-MEPs. Per part, 25 patients will be included. In order to investigate the effects of depth of anesthesia, a processed electroencephalogram (pEEG) monitor will be used. At pEEG values of 30, 40 and 50, mTc-MEP measurements will be performed. To examine the effect of blood pressure on mTc-MEPs the mean arterial pressure will be elevated from 60 to 100 mmHg during which mTc-MEP measurements will be performed. We hypothesize that by understanding the effects of depth of anesthesia and blood pressure on mTc-MEPs, the mTc-MEP monitoring can be interpreted more reliably. This may contribute to fewer false positive warnings. By performing this study after induction and prior to incision, this protocol provides a unique opportunity to study the effects of depths of anesthesia and blood pressure on mTc-MEPs alone with as little confounders as possible. Trial registration number NL7772.

Intraoperative neurophysiological monitoring during scoliosis surgery in patients with Duchenne muscular dystrophy.

PURPOSE: Little is known about the reliability and value of intraoperative neurophysiological monitoring (IONM) in patients with Duchenne muscular dystrophy (DMD) undergoing scoliosis correction surgery. The aim of this study was to investigate the feasibility of IONM and the cortical excitability in these patients. METHODS: Fifteen patients with DMD and scoliosis and 15 patients with adolescent idiopathic scoliosis (AIS) underwent scoliosis correction surgery with the use of IONM. IONM consisted of transcranial electrical stimulation motor evoked potential (Tc-MEP) and somatosensory evoked potential (SSEP) monitoring. The highest Tc-MEP amplitudes were collected to test the feasibility. Preoperative compound muscle action potentials (CMAPs) and transcranial magnetic stimulation (TMS)-MEPs were recorded to test the cortical excitability. SSEPs were scored as elicitable or not elicitable. RESULTS: Tc-MEP amplitudes were significantly lower in the DMD group for both the gastrocnemius and tibialis anterior muscles. However, the abductor hallucis muscle had similar amplitudes in both the DMD as the AIS group. TMS/CMAP and Tc-MEP/CMAP ratios were similar in the DMD and AIS group (P = 0.126 and P = 0.792 respectively). CONCLUSIONS: Tc-MEP and SSEP monitoring is feasible, particularly when Tc-MEPs are recorded from the abductor hallucis muscle in patients with DMD. Similar TMS/CMAP and Tc-MEP/CMAP ratios show that there were no differences observed in cortical excitability between the groups. IONM seems a feasible and valuable neurophysiological tool to signal possible surgically induced damage to the spinal cord during scoliosis correction surgery in patients with DMD.

Insights from the supplementary motor area syndrome in balancing movement initiation and inhibition.

The supplementary motor area (SMA) syndrome is a characteristic neurosurgical syndrome that can occur after unilateral resection of the SMA. Clinical symptoms may vary from none to a global akinesia, predominantly on the contralateral side, with preserved muscle strength and mutism. A remarkable feature is that these symptoms completely resolve within weeks to months, leaving only a disturbance in alternating bimanual movements. In this review we give an overview of the old and new insights from the SMA syndrome and extrapolate these findings to seemingly unrelated diseases and symptoms such as Parkinson's disease (PD) and tics. Furthermore, we integrate findings from lesion, stimulation and functional imaging studies to provide insight in the motor function of the SMA.

Different distal-proximal movement balances in right- and left-hand writing may hint at differential premotor cortex involvement.

Right-handed people generally write with their right hand. Language expressed in script is thus performed with the hand also preferred for skilled motor tasks. This may suggest an efficient functional interaction between the language area of Broca and the adjacent ventral premotor cortex (PMv) in the left (dominant) hemisphere. Pilot observations suggested that distal movements are particularly implicated in cursive writing with the right hand and proximal movements in left-hand writing, which generated ideas concerning hemisphere-specific roles of PMv and dorsal premotor cortex (PMd). Now we examined upper-limb movements in 30 right-handed participants during right- and left-hand writing, respectively. Quantitative description of distal and proximal movements demonstrated a significant difference between movements in right- and left-hand writing (p<.001, Wilcoxon signed-rank test). A Distal Movement Excess (DME) characterized writing with the right hand, while proximal and distal movements similarly contributed to left-hand writing. Although differences between non-language drawings were not tested, we propose that the DME in right-hand writing may reflect functional dominance of PMv in the left hemisphere. More proximal movements in left-hand writing might be related to PMd dominance in right-hemisphere motor control, logically implicated in spatial visuomotor transformations as seen in reaching.