Cutsforth‐Gregory, Jeremy K.

Objective Cerebrospinal fluid-venous fistula is an uncommon cause of spontaneous spinal cerebrospinal fluid leak (SSCSFL). We aim to describe the clinical presentation, imaging evaluation, treatment and outcome of SSCSFL secondary to cerebrospinal fluid-venous fistula. Methods A retrospective review was undertaken of SSCSFL cases secondary to cerebrospinal fluid-venous fistula confirmed radiologically or intraoperatively, seen at our institution from January 1994 to March 2019. Cases with undetermined SSCSFL etiology, alternative etiology or unconfirmed fistula were excluded. Results Forty-four of 156 patients met the inclusion criteria (31 women, 13 men). Mean age of symptom onset was 52.6 years (SD 8.7, range 33–71 years). Headache was the presenting symptom in almost all, typically daily (69%), and most often in occipital/suboccipital regions. Headache character was most commonly pressure (38%), followed by throbbing/pulsing (21.4%). Orthostatic headache worsening occurred in 69% and an even greater percentage of patients (88%) reported Valsalva-induced headache exacerbation or precipitation. Headache occurred in isolation to Valsalva maneuvers in 12%. Of 37 patients with documented cerebrospinal fluid opening pressure, 13% were <6 cmH 2 O; 84%, 7–20 cmH 2 O; and one, 25 cmH 2 O. Fistulas were almost exclusively thoracic (95.5%). Only one patient responded definitively to epidural blood patch (EBP). Forty-two patients underwent surgery. Most improved following surgery; 48.7% were completely headache free and 26.8% had at least 50% improvement. Conclusion In our series, cerebrospinal fluid-venous fistula was associated with a greater occurrence of Valsalva-induced headache exacerbation or precipitation than orthostatic headache and did not respond to EBP. Surgery provided significant improvement. Cerebrospinal fluid-venous fistula should be considered early in the differential diagnosis of Valsalva-induced (“cough”) headache.

Objectives To develop neurology scenarios for use with the Quality Improvement Knowledge Application Tool Revised (QIKAT-R), gather and evaluate validity evidence, and project the impact of scenario number, rater number and rater type on score reliability. Methods Six neurological case scenarios were developed. Residents were randomly assigned three scenarios before and after a quality improvement (QI) course in 2015 and 2016. For each scenario, residents crafted an aim statement, selected a measure and proposed a change to address a quality gap. Responses were scored by six faculty raters (two with and four without QI expertise) using the QIKAT-R. Validity evidence from content, response process, internal structure, relations to other variables and consequences was collected. A generalisability (G) study examined sources of score variability, and decision analyses estimated projected reliability for different numbers of raters and scenarios and raters with and without QI expertise. Results Raters scored 163 responses from 28 residents. The mean QIKAT-R score was 5.69 (SD 1.06). G-coefficient and Phi-coefficient were 0.65 and 0.60, respectively. Interrater reliability was fair for raters without QI expertise (intraclass correlation = 0.53, 95% CI 0.30 to 0.72) and acceptable for raters with QI expertise (intraclass correlation = 0.66, 95% CI 0.02 to 0.88). Postcourse scores were significantly higher than precourse scores (6.05, SD 1.48 vs 5.22, SD 1.5; p < 0.001). Sufficient reliability for formative assessment (G-coefficient > 0.60) could be achieved by three raters scoring six scenarios or two raters scoring eight scenarios, regardless of rater QI expertise. Conclusions Validity evidence was sufficient to support the use of the QIKAT-R with multiple scenarios and raters to assess resident QI knowledge application for formative or low-stakes summative purposes. The results provide practical information for educators to guide implementation decisions.

Background and objective Epidural blood patch (EBP) is a safe and effective treatment for spontaneous intracranial hypotension (SIH), but clinical and procedural variables that predict EBP efficacy remain nebulous. Methods This study is an institutional review board-approved retrospective case series with dichotomized EBP efficacy defined at 3 months. The study included 202 patients receiving 604 EBPs; iatrogenic cerebrospinal fluid leaks were excluded. Results Of the EBPs, 473 (78%) were single-level, 349 (58%) lumbar, 75 (12%) bilevel, and 56 (9%) multilevel (≥3 levels). Higher volume (OR 1.64; p<0.0001), bilevel (3.17, 1.91–5.27; p<0.0001), and multilevel (117.3, 28.04–490.67; p<0.0001) EBP strategies predicted greater efficacy. Only volume (1.64, 1.47–1.87; p<0.0001) remained significant in multivariate analysis. Site-directed patches were more effective than non-targeted patches (8.35, 0.97–72.1; p=0.033). Lower thoracic plus lumbar was the most successful bilevel strategy, lasting for a median of 74 (3–187) days. Conclusions In this large cohort of EBP in SIH, volume, number of spinal levels injected, and site-directed strategies significantly correlated with greater likelihood of first EBP efficacy. Volume and leak site coverage likely explain the increased efficacy with bilevel and multilevel patches. In patients with cryptogenic leak site, and either moderate disability, negative prognostic brain MRI findings for successful EBP, or failed previous lumbar EBP, a low thoracic plus lumbar bilevel EBP strategy is recommended. Multilevel EBP incorporating transforaminal administration and fibrin glue should be considered in patients refractory to bilevel EBP. An algorithmic approach to treating SIH is proposed.

Among medical students, neurosceince is considered a notoriously difficult subject. This challenges faculty to teach preclinical neurology in more engaging, efficient, and prioritized ways. Traditional approaches to neuroscience instruction typically begin with neuroanatomy and advance to clinical problem solving after this foundation of knowledge is in place. Over the past 45 years, neurology faculty at Mayo Clinic Alix School of Medicine have developed and iteratively refined an inverted approach called The Basic Four. The Basic Four uses authentic clinical scenarios as the basis for neuroscience instruction and incorporates principles from cognitive load theory to calibrate load on students’ working memory. This perspective describes The Basic Four and illustrates how cognitive load theory can be used to enhance case-based learning.

Objective To review the clinical and radiographic characteristics of orthostatic headache following suboccipital craniectomy without CSF leak after encountering 2 such patients. Background Orthostatic headache may occur without CSF leak, suggesting alternative mechanisms for postural head pain in some patients. Methods Patients who were referred for orthostatic headache and suspected CSF leak within 1 year after suboccipital craniectomy but who had negative post‐operative head and spine MRI, normal radioisotope cisternography, and normal or elevated CSF opening pressure were identified and their medical records reviewed. Results Two patients satisfied all inclusion criteria. One underwent suboccipital craniectomy for treatment of Chiari malformation type I in adolescence; the same surgical approach was used to resect a posterior fossa meningioma in the second. Both patients had non‐orthostatic headache before surgery and newly developed orthostatic headache later. Delay from surgery to orthostatic headache onset was variable (2–9 months). Headaches were predominantly occipital and pressure‐like, worsened by upright posture, bending forward, and exertion. MRI consistently showed adequate decompression of the posterior fossa. Epidural blood patches were unhelpful in the one patient in whom they were performed. Conclusions Orthostatic headaches may develop after suboccipital craniectomy in the absence of CSF leak. Possible mechanisms include (1) scarring of the dura in the posterior fossa that leads to compensatory increased distensibility of lumbar dura and (2) sensitization of mechanosensitive dural nociceptors from altered skull‐dura apposition.

Abstract The synucleinopathies—Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, and pure autonomic failure—result from distinct patterns of abnormal α‐synuclein aggregation throughout the nervous system. Autonomic dysfunction in these disorders results from variable involvement of the central and peripheral autonomic networks. The major pathologic hallmark of Parkinson's disease and dementia with Lewy bodies is Lewy bodies and Lewy neurites; of multiple system atrophy, oligodendroglial cytoplasmic inclusions; and of pure autonomic failure, peripheral neuronal cytoplasmic inclusions. Clinical manifestations include orthostatic hypotension, thermoregulatory dysfunction, gastrointestinal dysmotility, and urogenital dysfunction with neurogenic bladder and sexual dysfunction. Strong evidence supports isolated idiopathic rapid eye movement sleep disorder as a significant risk factor for the eventual development of synucleinopathies with autonomic and/or motor involvement. In contrast, some neurologically normal elderly individuals have Lewy‐related pathology. Future work may reveal protective or vulnerability factors that allow some patients to harbor Lewy pathology without overt autonomic dysfunction. © 2018 International Parkinson and Movement Disorder Society