Precision, reliability and application of the Wilkins Rate of Reading Test.

BACKGROUND: The Wilkins Rate of Reading Test (WRRT) enables rapid measurement of reading speed using text passages that have no semantic content and demand minimal word recognition skills. It is suited to applications where the primary interest is in the influence of visual and ocular motor factors on reading rate. METHODS: We obtained estimates of precision and reliability of WRRT from four data samples (A-D) collected independently by the authors: (A) n = 118 adults; (B) n = 90 adults; (C) n = 787 children; (D) n = 134 children. Each participant was asked to read aloud as quickly and accurately as possible, for 1 min, and results were recorded as number of words read correctly per minute (wcpm). RESULTS: Estimates of precision are given by the within-subjects standard deviation sw , and reliability by the intraclass correlation coefficient for single measurements r1 . For each sample these estimates were (A) sw  = 11.5 wcpm, r1  = 0.85; (B) sw  = 3.8 wcpm, r1  = 0.98; (C) sw  = 6.7 wcpm, r1  = 0.93; (D) sw  = 6.2 wcpm, r1  = 0.94. CONCLUSION: The reliability of WRRT reflects large variation in reading rate between individuals compared to within-individual variability, indicating that it is a good test for discriminating differences in reading speed between individuals. The precision of the test varies from 3.8 wcpm to 11.5 wcpm among samples, and the pooled value of 7.2 wcpm, provides a basis for setting a population-wide criterion for minimum detectable change of reading rate in individuals over time. Nevertheless, a preferable way of monitoring change in an individual would be to use a criterion determined from estimates of that individual's baseline variation in WRRT scores.

Neuromuscular Mimics of Entrapment Neuropathies of Upper Extremities.

Introduction: Carpal tunnel syndrome and ulnar neuropathy are such common maladies affecting the upper extremties that they often become the default diagnosis when patients complain of numbness, pain, or weakness of the hands. While often correct, there are a number of other conditions that can also cause sensory or motor loss of the hands, which should be considered when appropriate, as they can mimic upper extremity entrapment syndromes. Methods: In this review, we will discuss such mimics, including Charcot-Marie-Tooth disease, multifocal motor neuropathy, hereditary neuropathy with pressure palsies, mononeuropathy multiplex, Lewis-Sumner syndrome, brachial plexitis (Parsonage-Turner syndrome), myotonic dystrophy, inclusion body myopathy, and distal myopathy of Welander. We will discuss the clinical presentation, as well as diagnostic testing, treatment (if available), and prognosis. Conclusion: The objective is to provide a differential diagnosis for those patients who do not fit well clinically or respond to usual therapy for entrapment neuropathy of the upper extremities.

12 versus 24 h bed rest after acute ischemic stroke thrombolysis: a preliminary experience.

BACKGROUND: The practice of ≥24 h of bed rest after acute ischemic stroke thrombolysis is common among hospitals, but its value compared to shorter periods of bed rest is unknown. METHODS: Consecutive adult patients with a diagnosis of ischemic stroke who had received intravenous thrombolysis treatment from 1/1/2010 until 4/13/2016, identified from the local ischemic stroke registry, were included. Standard practice bed rest for ≥24 h, the protocol prior to 1/27/2014, was retrospectively compared with standard practice bed rest for ≥12 h, the protocol after that date. The primary outcome was favorable discharge location (defined as home, home with services, or acute rehabilitation). Secondary outcome measures included incidence of pneumonia, NIHSS at discharge, and length of stay. RESULTS: 392 patients were identified (203 in the ≥24 h group, 189 in the ≥12 h group). There was no significant difference in favorable discharge outcome in the ≥24 h bed rest protocol compared with the ≥12 h bed rest protocol in multivariable logistic regression analysis (76.2% vs. 70.9%, adjusted OR 1.20 CI 0.71-2.03). Compared with the ≥24 h bed rest group, pneumonia rates (8.3% versus 1.6%, adjusted OR 0.12 CI 0.03-0.55), median discharge NIHSS (3 versus 2, adjusted p = .034), and mean length of stay (5.4 versus 3.5 days, adjusted p = .006) were lower in the ≥12 h bed rest group. CONCLUSION: Compared with ≥24 h bed rest, ≥12 h bed rest after acute ischemic stroke reperfusion therapy appeared to be similar. A non-inferiority randomized trial is needed to verify these findings.

Clinical Use of the Kannada and English Rate of Reading Tests.

The rate of reading test in which randomly ordered common words are read aloud has found use in optometric and educational practice as a means of assessing visual aspects of reading largely independently of comprehension. English and Kannada versions of the rate of reading test were administered to 761 children aged between 9 and 15 years. These children were recruited from four private and five state schools in Udupi Taluk that had English and Kannada, respectively, as the principal medium of instruction. The results showed that the reading rate increased with age, as expected, but depended on the language of the test and the medium of instruction. The study emphasizes the importance of using normative data based on age and the language of instruction used in school. It also suggests age-specific criteria to measure the efficacy of any visual intervention aimed at improving reading speed. The test can be used to assess (1) educational under-performance in reading and (2) the effects of optometric and educational intervention, and separate norms appropriate for each use are presented.

Neurohistiocytosis of the Cerebellum: A Rare Cause of Ataxia.

Erdheim-Chester disease (ECD) is a non-Langerhans cell histiocytosis that affects multiple body organs, notably the skeletal system. We examined a 58-year-old man who presented with ataxia and T2 hyperintensity of the middle cerebellar peduncles and dentate nuclei without contrast enhancement on MRI brain. Workup for malignancy revealed "hairy kidneys" on CT scan of the abdomen, and excisional biopsy of the retroperitoneal mass for concerns of lymphoma revealed foamy histiocytes that tested positive for CD68 and negative for CD1a, confirming the diagnosis of ECD. Further genetic testing on excised tissue revealed BRAF (V600E) gene mutation that is present in 50% of ECD patients. Treatment was initiated with targeted therapy using the BRAF inhibitor Dabrafenib. X-ray of the lower extremities did not reveal sclerosis of the long bones, and bone scan with technetium 99 was negative except for a nonspecific tracer uptake in left calvarial bone with no corresponding CT changes or T1/T2 signal changes on MRI. His MRI brain revealed classic cerebellar involvement in ECD without other central nervous system (CNS) involvement. It has been postulated that bone involvement is almost universal in ECD; however, our patient with ECD had ataxia and cerebellar involvement without significant bone involvement, as evidenced by bone scan. This is a rare presentation of ECD affecting the CNS and sparing the skeletal system. It confirms the wide spectrum of presentation this multisystem disease can have.

Repetitive nerve stimulation and single-fiber electromyography in the evaluation of patients with suspected myasthenia gravis or Lambert-Eaton myasthenic syndrome: Review of recent literature.

INTRODUCTION: Our aim in this study was to provide an updated literature review of electrodiagnostic testing in myasthenia gravis and Lambert-Eaton myasthenic syndrome. METHODS: A systematic review of the recent literature was performed using the following key words: myasthenia gravis (MG); Lambert-Eaton myasthenic syndrome (LEMS); electromyography (EMG); repetitive nerve stimulation (RNS); single-fiber electromyography (SFEMG); nerve conduction study; and normative values. RESULTS: Several articles supported testing of facial, bulbar, and respiratory muscles in the diagnosis of neuromuscular junction (NMJ) disorders, including muscle-specific kinase antibody (MuSK)-seropositive MG. Several articles supported use of concentric needle EMG as an alternative to SFEMG jitter in disorders of neuromuscular transmission. A limited number of articles addressed measurement of area (vs. amplitude) decrement in RNS and decreasing the threshold of post-exercise facilitation. CONCLUSIONS: Electrodiagnostic testing continues to be useful for diagnosis of MG and LEMS, although the quality of the evidence is not great. This literature review summarizes RNS and jitter measurement of facial and respiratory muscles and use of concentric needle EMG for SFEMG.

Lexical decisions in adults with low and high susceptibility to pattern-related visual stress: a preliminary investigation.

Pattern-related visual stress (PRVS) is a form of sensory hypersensitivity that some people experience when viewing high contrast repeating patterns, notably alternating dark and light stripes. Those susceptible to PRVS typically have a strong aversion to such stimuli, and this is often accompanied by experiences of visual discomfort and disturbance. The patterns most likely to elicit symptoms of PRVS have a square-wave grating configuration of spatial frequency ~3 cycles/degree. Such stimuli are characteristic of printed text in which lines of words and the spaces between them present a high contrast grating-like stimulus. Consequently, much printed reading material has the potential to elicit PRVS that may impair reading performance, and this problem appears to be common in individuals with reading difficulties including dyslexia. However, the manner in which PRVS affects reading ability is unknown. One possibility is that the early sensory visual stress may interfere with the later cognitive word recognition stage of the reading process, resulting in reading performance that is slower and/or less accurate. To explore the association of PRVS with word recognition ability, lexical decision performance (speed and accuracy) to words and pronounceable non-words was measured in two groups of adults, having low and high susceptibility to PRVS. Results showed that lexical decisions were generally faster but less accurate in high-PRVS, and also that high-PRVS participants made decisions significantly faster for words than for non-words, revealing a strong lexicality effect that was not present in low-PRVS. These findings are novel and, as yet, unconfirmed by other studies.

Small-fiber degeneration in alcohol-related peripheral neuropathy.

BACKGROUND: Alcohol-related peripheral neuropathy (ALN) is generally characterized as an axonal large-fiber polyneuropathy caused by thiamine deficiency. We hypothesized, based on clinical observations, that ALN is associated with a small-fiber polyneuropathy that can be diagnosed with skin biopsy in heavy alcohol drinking subjects with normal thiamine status. METHODS: Eighteen individuals (9 heavy alcohol drinking subjects and 9 healthy control subjects) were assessed for the potential utility of skin biopsies in detecting ALN-associated small nerve fiber degeneration. Heavy drinking was defined as greater than 4 drinks/d and 5 drinks/d in women and men, respectively, as determined by the Timeline Follow-Back and lifetime drinking history. All subjects underwent neurological examination, nerve conduction studies, and skin biopsies to quantify end nerve fiber densities (ENFD). Other causes of neuropathy were excluded and thiamine status was assessed. RESULTS: Average ENFD were significantly decreased at the calf in the alcohol group as compared with control group (p < 0.0001). Histological sections demonstrated striking attrition and architectural simplification of intraepidermal nerve fibers in the heavy alcohol drinking subjects. There were no significant intergroup differences with respect to clinical assessments of neuropathy or thiamine status. CONCLUSIONS: ALN is associated with a small-fiber neuropathy that can be detected with skin biopsy in heavy alcohol drinking individuals with normal thiamine status. Skin biopsy is a useful, minimally invasive biomarker that could extend studies to understand the effect of alcohol on the peripheral nerves and to evaluate potential therapeutic agents in larger clinical trials.

Alcohol-related peripheral neuropathy: nutritional, toxic, or both?

Alcohol-related peripheral neuropathy (ALN) is a potentially debilitating complication of alcoholism that results in sensory, motor, and autonomic dysfunction. Unfortunately, ALN is rarely discussed as a specific disease entity in textbooks because it is widely assumed to primarily reflect consequences of nutritional deficiency. This hypothesis is largely based on observations first made over eight decades ago when it was demonstrated that thiamine deficiency (beriberi) neuropathy was clinically similar to ALN. In recent studies, failure of thiamine treatment to reverse ALN, together with new information demonstrating clinical and electrophysiological distinctions between ALN and nutritional deficiency neuropathies, suggests that alcohol itself may significantly predispose and enhance development of neuropathy in the appropriate clinical setting. We reviewed the evidence on both sides and conclude that ALN should be regarded as a toxic rather than nutritional neuropathy.

The Charcot joint: a modern neurologic perspective.

The Charcot joint, or Charcot neuroarthropathy, is a syndrome that was described over 140 years ago but one with very little exposure in the neurologic literature. We present a case recently seen and then discuss the history, epidemiology, pathophysiology, clinical features, and diagnosis of acute and chronic Charcot joint disease with particular emphasis on the value and limitations of imaging. A diagnostic algorithm is proposed. We also review the therapeutic strategies available for acute and chronic Charcot joints with a treatment algorithm. This review is aimed at enhancing the awareness of neurologists regarding Charcot neuroarthropathy, because they are often the principal caregivers for patients with peripheral neuropathy. We hope to promote early detection of acute Charcot neuroarthropathy, thereby reducing or preventing the bony deformation of chronic Charcot neuroarthropathy.

Safety of nerve conduction studies in patients with peripheral intravenous lines.

Nerve conduction studies (NCS) may be deferred because of a perceived risk of cardiac arrhythmia in the presence of same-limb peripheral intravenous lines. Patients with implanted pacemakers or defibrillators provide a model in whom this risk can be assessed. Twenty patients, seven with pacemakers and 13 with defibrillators, had peripheral intravenous lines placed during routine care and underwent NCS in the same limb. NCS were performed with the intravenous line clamped and then with saline open to gravity. The implanted cardiac device was interrogated before and after the study. During NCS the surface electrocardiogram and intracardiac electrograms were monitored continuously. Electrical impulses generated during routine NCS were never detected by the sensing amplifiers of the pacemakers/defibrillators and did not affect the programmed settings or interfere with pacing of the device. Routine NCS are safe in patients with same-limb peripheral intravenous lines, even with saline open to gravity.

Frequency and predictors of nonalcoholic fatty liver disease in myotonic dystrophy.

Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease that is strongly associated with insulin resistance. Myotonic dystrophy (DM1) is the most common form of adult-onset muscular dystrophy, and there is a high frequency of insulin resistance due to insulin receptor mRNA splicing defects in muscle tissue. The frequency and predictors of NAFLD in this population have not been described. Thirty-six patients with DM1 were prospectively assessed for the presence of NAFLD and insulin resistance. NAFLD was defined by abnormal liver chemistry tests with ultrasound or pathologic evidence of steatosis in the absence of other liver disease. Abnormal liver chemistry tests were found in 44% of DM1 patients (mean ALT 73 +/- 21 U/L, AST 53 +/- 15 U/L), and 87% were attributable to NAFLD. Clinical predictors of NAFLD included increased insulin resistance by the homeostasis model assessment (HOMA) method (9.5 vs. 4.0 U, P = 0.03), elevated fasting insulin (40.4 vs. 16.1 microIU/ml, P = 0.03), abdominal obesity (98.6 vs. 90.8 cm, P = 0.03), elevated triglycerides (195.7 vs. 136.8 mg/dl, P = 0.02), and elevated total cholesterol (213.6 vs. 180.6 mg/dl, P = 0.02). NAFLD is very common and should be considered in the management of DM1. It is strongly associated with markers of insulin resistance and features of the metabolic syndrome. These findings support the role of peripheral insulin resistance in the pathogenesis of NAFLD.

Weighted 2 x 2 kappa coefficients: recommended indices of diagnostic accuracy for evidence-based practice.

OBJECTIVES: The diagnostic accuracy of a clinical test is typically evaluated by comparing the classification of individuals by the test with their classification by some diagnostic gold standard. The most popular indices of diagnostic accuracy are sensitivity, specificity, and positive and negative predictive values. However, these measures are affected by the fact that some diagnostic decisions will be correct by chance, resulting in values that differ widely between indices, and clinicians may be confused as to whether results indicate that a test is good or poor. In keeping with the principle in evidence-based practice that decisions should be based on evidence not guesswork, we might expect that measures of diagnostic accuracy should therefore be chance corrected. The objective of this article was to advocate this and draw attention to indices that achieve this requirement. STUDY DESIGN AND SETTING: The principles underlying calculations of diagnostic accuracy are presented as a framework for understanding the problem and its solution. RESULTS: Disparities between different indices of diagnostic accuracy may be resolved by adjusting them to correct for chance effects. This produces a pair of weighted 2 x 2 "diagnostic" kappa coefficients offering a number of theoretical and practical advantages. CONCLUSION: Routine use of weighted 2 x 2 kappa coefficients as indices of diagnostic accuracy is recommended.

Seventh cranial neuropathy.

Facial neuropathy, or seventh cranial neuropathy, is the most common cranial neuropathy. The anatomy of the facial nerve is rather complex for a cranial nerve, with a long intracranial course, in which the nerve takes three bends (or genu). Electrodiagnosis can be helpful in prognosis, but not before several days. Imaging is rarely indicated in Bell's palsy, but is often abnormal nonetheless, and can be very useful in other causes of facial neuropathy. The clinical presentation is of unilateral facial weakness of upper and lower face, hyperacusis, dysgeusia, and disordered lacrimation and salivation. Many different disease processes can result in facial neuropathy, but 70% of cases are idiopathic, or as it is best known, Bell's palsy. Ramsay Hunt syndrome, defined as facial neuropathy with herpes zoster oticus, is another common cause. Steroids given acutely are beneficial in improving outcome in Bell's palsy, and antiviral therapy seems helpful in more severe cases. Antiviral therapy is definitely helpful in Ramsay Hunt disease when given within 3 days of onset. Antibiotics are helpful in Lyme facial neuropathy, which has a very good prognosis.

Use of visual search in the assessment of pattern-related visual stress (PRVS) and its alleviation by colored filters.

PURPOSE: Visual search measures have been used to evaluate the effects of pattern-related visual stress (PRVS), and its alleviation by colored filters, but tasks and results have varied between studies. Performance on a high-difficulty search task was measured in individuals having low- and high-PRVS susceptibility. METHODS: Two PRVS groups (low and high) were formed on the basis of participants' responses to a visual symptoms questionnaire and perceptions of a high-contrast grating pattern. Each participant searched for multiple instances of a single-digit number (target) within an array of similar numbers (distractors). Performance was measured by response time and error count. A three-factor, mixed-factorial ANOVA design was used to investigate the effects of PRVS group, a high-contrast background PATTERN, an overlay of an individually-selected COLOR. RESULTS: Individuals classified with high visual stress were found to experience significantly greater improvement in reading performance (F((1,26)) = 24.579, P < 0.001) and reduction in the number of errors (F((1,26)) = 9.502, P = 0.005) when performing the Wilkins Rate of Reading Test with a colored overlay than those with low visual stress. Error count was significantly higher in the high-PRVS group, when subjects were performing a visual search task, in the absence of either PATTERN or COLOR, but response time was not significantly different. Neither response time nor error count was significantly affected by background PATTERN and/or colored overlay. CONCLUSIONS: Results of this and previous studies confirm that visual search measures may be helpful in the assessment of PRVS, but several important methodological issues may limit their application in this context.

Unilateral thigh atrophy and weakness in hip osteoarthritis.

Osteoarthritis is a common condition that affects a significant percentage of people in the United States. The case and discussion will serve to introduce to the neurologist the issue of hip osteoarthritis causing thigh atrophy and weakness. The pathogeneses of muscular atrophy in the setting of osteoarthritis and of muscle weakness as a cause of osteoarthritis will be explored.

Safety of nerve conduction studies in patients with implanted cardiac devices.

Patients with implanted cardiac devices and their physicians may defer important electrodiagnostic testing because of anxiety about potential negative effects on the device. To determine the safety of routine nerve conduction studies (NCS) in this population, 10 patients with permanent dual-chamber pacemakers of various types and five patients with implanted cardiac defibrillators (ICD) underwent nerve stimulation at sites commonly used during NCS. The implanted cardiac device was interrogated before and after the study and there was continuous monitoring of the surface electrocardiogram (ECG) and atrial and ventricular electrograms. Electrical impulses generated during routine NCS were never detected by the sensing amplifier and did not affect the programmed settings of the implanted cardiac device. We conclude that routine NCS is safe in patients with implanted cardiac pacemakers with bipolar sensing configurations and defibrillators.