Neurology and the clinical anatomist

Clinical examination allows the neurologist to test hypotheses generated by their interpretation of the patient's story. By eliciting abnormal clinical signs, the examining doctor works out a differential diagnosis for the part of the nervous system affected and, using information from the clinical history, a differential diagnosis of the pathology. Clinical examination also allows the clinician to observe and quantify function, hear more story and provide reassurance. The focus of the examination should be dictated by the hypothesis being tested, the patient's clinical state and the situation. Examination of the different parts of the nervous system remains very important in all clinical situations as the best available index of function of the nervous system as a whole.

The Importance of Neurological Examination for the Indication of Computed Tomography of the Brain in Pediatric Emergency Room

Objectives:

In this study, records of the children who underwent Computed Tomography of the Brain (CTB) were reviewed to increase the awareness of pediatricians to protect patients from radiation, whether CTB was used with right indications or if it was determinative for diagnosis.

Methods:

In total, in this study, 342 cases applied to our Pediatric Emergency Polyclinic between January 2005-December 2010 were retrospectively evaluated regarding complaints at admission, neurological examination and CTB results. The sensitivity and specificity of the neurological examination in detecting the CTB pathology was determined.

Results:

The results were normal in 319 of the 342 cases with CBT and abnormal in 23, out of which abnormal CTB results were only in three (0.99%) of the 301 patients with normal neurological examination results and in 20 (48.8%) of 41 patients with abnormal neurological examination results. The difference between the two groups was statistically significant (p=0.001). The sensitivity and specificity of the neurological examination in detecting CTB pathology were 87% and 94%, respectively.

Conclusion:

Detailed neurological examination of the patients in the pediatric emergency department has a key role in determining the indications for CTB. Clinical follow-up should guide neuroradiological imaging in children with normal results of the neurological examination.

Under-Recognition of Cervical Dystonia: An Essential Tremor Patient with Numerous Textbook Features of Cervical Dystonia

Background

Physical examination findings of dystonia are often underrecognized, especially in the setting of other movement disorders such as essential tremor (ET).

Phenomenology Shown

A patient with ET exhibited numerous textbook features of cervical dystonia, which were misattributed to ET by a primary care physician and two neurologists.

Educational Value

To provide a clear and unmistakable visual example of the clinically significant characteristics of cervical dystonia in the setting of concomitant ET.

Essential tremor: a nuanced approach to the clinical features

Click here to listen to the Podcast Essential tremor is the most common form of tremor in humans. Given neurologists' high exposure to this condition, and its seemingly straightforward phenotype, it might seem easy to diagnose. However, 30%-50 % of patients labelled as having 'essential tremor' have other diagnoses, mostly Parkinson's disease and dystonia. The tremor of essential tremor is neither non-descript nor featureless but is multifaceted and highly patterned. This review focuses on its clinical features, beginning with a discussion of tremors and then briefly discussing its additional motor features, and presents several aids to help distinguish essential tremor from Parkinson's disease and dystonia. Careful attention to certain clinical nuances will aid the diagnosis and care of patients with essential tremor.

[The Russian version of Coma Recovery Scale-revised - a standardized method for assessment of patients with disorders of consciousness]

The authors officially present for the first time the Russian version of Coma Recovery Scale-Revised (CRS-R). Today CRS-R is the only validated scale in Russian for assessment of patients with chronic disorders of consciousness (DOC). The study showed high consistency for different researchers, high sensitivity in the evaluation of patients over time as well as high concurrent validity. This article contains the text of the scale and recommendations how to use CRS-R and interpret the data. Presented version of the CRS-R is recommended for use in DOC patients. Russian version of the CRS-R is a standardized, comprehensive and systematic approach to the examination and assessment of patients with chronic DOS. It ensures the standard approach to examination and assessment that warrants the accuracy and homogeneity of the obtained results.

Conjugate Eye Deviation in Unilateral Lateral Medullary Infarction

Background and Purpose

The initial diagnosis of medullary infarction can be challenging since CT and even MRI results in the very acute phase are often negative.

Methods

A retrospective, observer-blinded study of horizontal conjugate eye deviation was performed in 1) 50 consecutive patients [age 58±15 years (mean±SD), 74% male, National Institutes of Health Stroke Scale 2±1] with acute unilateral lateral medullary infarction as seen in MRI (infarction group), 2) 54 patients with transient brainstem symptoms [transient ischemic attack of brainstem (TIA) group; age 69±16 years, 59% male], and 3) 53 patients (age 59±20 years, 49% male) with diagnoses other than stroke (control group).

Results

Conjugate eye deviation was found in all patients in the infarction group [n=47 (94%) with ipsilesional deviation and n=3 (6%) with contralesional deviation] compared to 41% (n=22) in the brainstem TIA group and 15% (n=8) in the control group (p<0.0001). Within all groups mean deviation and range were similar for both sides (to the right vs. to the left side 26.6°±12.3 vs. 26.1°±12.3 in the infarction group, 10.5°±5.8 vs. 8.4°±6.3 in the brainstem TIA group and 4.5°±3.2 vs. 7.5°±3.2 in the control group). The extent of eye deviation was significantly greater in the infarction group (p<0.05).

Conclusions

All patients with MRI-demonstrated unilateral medullary infarction showed conjugate eye deviation. Therefore, conjugate eye deviation in patients with suspected acute lateral medullary infarction is a helpful sensitive sign for supporting the diagnosis, particularly if the deviation is >20°.

Identifying and Quantifying Neurological Disability via Smartphone

Embedded sensors of the smartphones offer opportunities for granular, patient-autonomous measurements of neurological dysfunctions for disease identification, management, and for drug development. We hypothesized that aggregating data from two simple smartphone tests of fine finger movements with differing contribution of specific neurological domains (i.e., strength & cerebellar functions, vision, and reaction time) will allow establishment of secondary outcomes that reflect domain-specific deficit. This hypothesis was tested by assessing correlations of smartphone-derived outcomes with relevant parts of neurological examination in multiple sclerosis (MS) patients. We developed MS test suite on Android platform, consisting of several simple functional tests. This paper compares cross-sectional and longitudinal performance of Finger tapping and Balloon popping tests by 76 MS patients and 19 healthy volunteers (HV). The primary outcomes of smartphone tests, the average number of taps (per two 10-s intervals) and the average number of pops (per two 26-s intervals) differentiated MS from HV with similar power to traditional, investigator-administered test of fine finger movements, 9-hole peg test (9HPT). Additionally, the secondary outcomes identified patients with predominant cerebellar dysfunction, motor fatigue and poor eye-hand coordination and/or reaction time, as evidenced by significant correlations between these derived outcomes and relevant parts of neurological examination. The intra-individual variance in longitudinal sampling was low. In the time necessary for performing 9HPT, smartphone tests provide much richer and reliable measurements of several distinct neurological functions. These data suggest that combing more creatively-construed smartphone apps may one day recreate the entire neurological examination.

The essential neurological examination of the unconscious patient in the emergency room

OBJECTIVE

To determine whether neurologists with long-term experience in the emergency room are in general agreement about the essential components of the neurological examination (NE) used on unconscious patients in whom an obvious cause for coma is lacking.

METHODS

We surveyed 31 board-certified practicing neurologists who regularly examine unconscious patients in the emergency room and asked them to list the specific components of the NE that they would normally choose to apply in at least 80% of cases.

RESULTS

Twenty-seven neurologists rated 24 of 38 items as essential steps of the neurological examination of the unconscious patient, with a high level of agreement amongst survey participants.

CONCLUSIONS

There was a high degree of consensus amongst the neurologists surveyed about which steps are essential for the NE of the unconscious patient. These findings provide an important source of validation for teaching this particular NE to medical students, as well as nonneurologists working in an emergency setting.

Index Finger Pointing (Likely a Subtle Form of Hand Dystonia): Prevalence Across Movement Disorders

Objective: To investigate the prevalence of index finger pointing (IFP) while walking, which is likely a subtle form of hand dystonia, in cranio-cervical focal dystonia syndromes, Parkinson's disease (PD), essential tremor (ET), and controls. Methods: We recruited patients with an established diagnosis of PD, dystonia, or ET and healthy controls. All participants were videotaped while walking. Videotapes were evaluated by the authors, blinded to diagnosis, to assess the presence or absence of IFP. Results: Two-hundred-fifty participants included 50 dystonia, 50 PD, 80 ET and 70 controls. IFP was present in 29/250 (11.6%) participants: 10 dystonia (20.0%), 8 PD (16.0%), 8 ET (10.0%), and 3 controls (3.8%) (p = 0.03). There was a significant evidence of a trend in the odds of having this sign among disorders with higher risk of dystonic features (dystonia>PD>ET>control; test for trend = 0.004). Among the 180 patients (dystonia, PD, and ET, i.e., excluding the 70 controls), IFP was present in 26 (14.4% prevalence). Conclusion: IFP during gait, likely a subtle form of hand dystonia, was observed in 14.4% of movement disorder patients. The highest prevalence was in dystonia, the second highest in a disease that is often accompanied by dystonia (PD), a lower prevalence among individuals with a disease that is rarely accompanied by dystonia (ET), and the lowest in controls.

The neurological examination adapted for neuropsychiatry

The neuropsychiatric examination includes standard neurological and cognitive examination techniques with several additional observations and tasks designed to capture abnormalities common among patients with neuropsychiatric disorders or neurocognitive complaints. Although useful as a screening tool, a single standardized rating scale such as the Mini Mental State Examination (MMSE) or the Montreal Cognitive Assessment (MoCA) is insufficient to establish a neuropsychiatric diagnosis. Extra attention is paid to findings commonly seen in the setting of psychiatric disorders, dementias, movement disorders, or dysfunction of cortical or subcortical structures. Dysmorphic features, dermatologic findings, neurodevelopmental signs, signs of embellishment, and expanded neurocognitive testing are included. The neuropsychiatric clinician utilizes the techniques described in this article to adapt the examination to each patient's situation, choosing the most appropriate techniques to supplement the basic neurological and psychiatric examinations in support of diagnostic hypotheses being considered. The added examination techniques facilitate diagnosis of neurocognitive disorders and enable neuropsychiatric formulation.

Neurological Soft Signs, Spontaneous and Treatment Emergent Extrapyramidal Syndromes in Black Africans With First Episode Schizophrenia

Background: Very little is known about the relationship between spontaneous and treatment-induced motor syndromes in Africans with first episode schizophrenia. Objective: We investigated the association between spontaneous NSS and EPS, with treatment-induced EPS in a homogenous sample of Black Africans with first episode schizophrenia. Methods: We examined Xhosa (South Africa) and Yoruba (Nigeria) patients, using the Neurological Evaluation Scale and extrapyramidal symptoms scale before and at 3 months after exposure to low dose flupenthixol decanoate. Pearson's correlations and Linear regression models, controlling for duration of untreated psychosis (D.U.P) and premorbid adjustments, were used in examining associations. Results: Among 99 participants in the baseline sample, 91 (91.8%) and 20 (20.2%) had at least one definite NSS and EPS, respectively, before exposure to antipsychotics. Treatment-induced EPS were recorded in 34 (38.6%). Spontaneous EPS was associated with treatment-emergent Akathisia in participants with a longer D.U.P (r = 0.75, β = 0.70, p = 0.008). This association was specific for Parkinsonism (r = 0.75, β = 0.85, p = 0.008) and dyskinesia (r = 0.75, β = 1.70, p = 0.008). Conclusion: Similar to previous findings for tardive dyskinesia in studies implementing longer-term follow-up, spontaneous EPS may also predict short-term antipsychotic-induced EPS such as akathisia. These results may be important for early identification of patients at risk of treatment-induced Akathisia-linked psychomotor agitation in first episode schizophrenia.

Use of Machine Learning Classifiers and Sensor Data to Detect Neurological Deficit in Stroke Patients

Background

The pronator drift test (PDT), a neurological examination, is widely used in clinics to measure motor weakness of stroke patients.

Objective

The aim of this study was to develop a PDT tool with machine learning classifiers to detect stroke symptoms based on quantification of proximal arm weakness using inertial sensors and signal processing.

Methods

We extracted features of drift and pronation from accelerometer signals of wearable devices on the inner wrists of 16 stroke patients and 10 healthy controls. Signal processing and feature selection approach were applied to discriminate PDT features used to classify stroke patients. A series of machine learning techniques, namely support vector machine (SVM), radial basis function network (RBFN), and random forest (RF), were implemented to discriminate stroke patients from controls with leave-one-out cross-validation.

Results

Signal processing by the PDT tool extracted a total of 12 PDT features from sensors. Feature selection abstracted the major attributes from the 12 PDT features to elucidate the dominant characteristics of proximal weakness of stroke patients using machine learning classification. Our proposed PDT classifiers had an area under the receiver operating characteristic curve (AUC) of .806 (SVM), .769 (RBFN), and .900 (RF) without feature selection, and feature selection improves the AUCs to .913 (SVM), .956 (RBFN), and .975 (RF), representing an average performance enhancement of 15.3%.

Conclusions

Sensors and machine learning methods can reliably detect stroke signs and quantify proximal arm weakness. Our proposed solution will facilitate pervasive monitoring of stroke patients.

Leptomeningeal metastases: a RANO proposal for response criteria

Leptomeningeal metastases (LM) currently lack standardization with respect to response assessment. A Response Assessment in Neuro-Oncology (RANO) working group with expertise in LM developed a consensus proposal for evaluating patients treated for this disease. Three basic elements in assessing response in LM are proposed: a standardized neurological examination, cerebral spinal fluid (CSF) cytology or flow cytometry, and radiographic evaluation. The group recommends that all patients enrolling in clinical trials undergo CSF analysis (cytology in all cancers; flow cytometry in hematologic cancers), complete contrast-enhanced neuraxis MRI, and in instances of planned intra-CSF therapy, radioisotope CSF flow studies. In conjunction with the RANO Neurological Assessment working group, a standardized instrument was created for assessing the neurological exam in patients with LM. Considering that most lesions in LM are nonmeasurable and that assessment of neuroimaging in LM is subjective, neuroimaging is graded as stable, progressive, or improved using a novel radiological LM response scorecard. Radiographic disease progression in isolation (ie, negative CSF cytology/flow cytometry and stable neurological assessment) would be defined as LM disease progression. The RANO LM working group has proposed a method of response evaluation for patients with LM that will require further testing, validation, and likely refinement with use.

A neurologic dysfunction scoring protocol for jaundiced neonates requiring exchange transfusion

AIM

To evaluate the performance of a neurologic assessment protocol among jaundiced infants requiring exchange transfusion (ET).

METHODS

We identified infants in a referral children's hospital who received ET and those who met the American Academy of Pediatrics (AAP) criteria for ET based on total serum bilirubin (TSB) levels. The performance of a bilirubin-induced neurologic dysfunction (BIND-M) scoring protocol for acute bilirubin encephalopathy (ABE) in detecting infants treated with ET in both groups was investigated by logistic regression analysis and c-statistic.

RESULTS

A total of 438 late-preterm and term infants were enrolled, out of which 141 (32.2%) received ET, and 155 (35.4%) met AAP criteria for ET. Infants with BIND-M scores of 3-6 (intermediate ABE) or 7-12 (advanced ABE) were significantly associated with ET in both groups, but not scores of 1-2 (mild ABE), with or without adjustment for confounding neurotoxicity risk factors. However, the discriminatory ability of BIND-M regression models was modestly satisfactory (c-statistic range: 0.693-0.791).

CONCLUSIONS

Our findings suggest that BIND-M is a potentially useful decision-making tool for ET and support current recommendation for immediate ET for infants with intermediate-to-advanced stages of ABE regardless of the TSB levels.

The comparison of general movements assessment and neurological examination during early infancy

This prospective single-blinded study was performed to evaluate general movements (GMs) in group of high-risk, low-birth-weight and preterm infants and to compare results with neurologic examination. All infants' neurologic examinations, Gross Motor Function Measurement (GMFM) and Bayley-III Scale were performed at the corrected age of 12 months. A total of 22 infants were included. Eight infants (group-1) (mean: 31.6±3.29 weeks, range: 25-36 weeks) had normal GMs in all recordings and were ultimately evaluated as "normal"; 12 (group-2) (mean: 31.6±3.29 weeks, range:2 5-35 weeks) had abnormal GMs during writhing movements period but had normal GMs in subsequent recordings and were evaluated as "normal"; and 2 infants (group-3) (mean:29.5±7.78 weeks, range:24-35 weeks) with consistent abnormal GMs who were evaluated as "abnormal." Complete agreement (kappa=1) was found between GMs and neurologic examination and significant agreement between GMs and cranial ultrasonography (kappa=0.76). When results of GMFM and Bayley-III were compared; statistically significant differences were found between group-1 and group-2 in "standing" parameter of GMFM (p < 0.05) and "cognitive" parameter of Bayley-III (p < 0.05). GMs assessment can help determine neurologic disorders in high-risk infant populations as an adjunct to other diagnostic techniques.

A station-based concept for teaching the neurological examination: A prospective quasi-experimental study

Background: The neurological examination is considered to be complex and contributes to the phenomenon of "neurophobia". It is traditionally taught in small groups by residents ("traditional concept"), making the learning success partially dependent on the resident's level of clinical training, didactic education and personal motivation. Aim of this study was to examine the effects of a newly developed concept ("station concept") for teaching the neurological examination on achieving an improved and more equal transfer of knowledge and practical skills. Methods: A prospective quasi-experimental design was used to compare the traditional concept with the newly developed station concept, in which the teaching content was divided in eight subdivisions (stations) with one resident being assigned to one station. The primary endpoints of the study were the differences in students' self-assessments of learning success in the different subdomains of the neurological examination, and secondary analyses focused on evaluation results of students and residents. Results: 144 students and 28 residents participated in the traditional concept (summer semester 2012) and 151 students and 28 residents in the station concept (winter semester 2012/13). In the station-concept students' self-assessment significantly improved in the domains "Motor System", "Coordination" and "Mental Status" compared to the traditional concept. Students' evaluation showed significant improvement in five out of eight points. Fifty percent of residents rated the new approach superior to the traditional approach, ten percent as inferior. Conclusion: The station concept improved students' self-assessed learning success as well as evaluation results while simultaneously achieving high acceptance in residents.

Baseline neurological evaluations in a hyperbaric trial of post-concussive syndrome

Standard neurologic examinations may not detect abnormalities in U.S. military service members with persistent post-concussive symptoms following mild traumatic brain injury. The Brain Injury and Mechanisms of Action of Hyperbaric Oxygen for Persistent Post-Concussive Symptoms after Mild Traumatic Brain Injury Study (BIMA) enrolled 71 participants September 2012-May 2014. Participants received: comprehensive neurological and oculomotor exam; balance testing (Berg Balance Scale-BBS; Romberg Test-RT, Sharpened Romberg Test-SRT); olfactory function (Brief Smell Identification Test-BSIT). Two trained neurologists conducted the examinations at a central facility in Colorado Springs. Median age was 32 years (range 21-53), 99% male, 82% Caucasian, 49% PTSD, 28% most recent qualifying injury three months to one year prior to enrollment, 32% blast injuries only, and 73% multiple injuries. Some participants presented with abnormal facial sensation (15%), abnormal tandem gait (13%), and tremor (11%). 54% had abnormal near point of convergence (abnormal range 13-80 cm). 86% scored ≥ 55 on the BBS, with no participant scoring ⟨ 50. 49% scored ⟨ 30 seconds on the best trial of the SRT. RT was abnormal in 10%. 15% of participants scored ≤ 9 (out of 12) on BSIT, about twice what is expected in a normal population. The neurological examination found abnormalities across a range of testing, with convergence insufficiency and SRT having the most sensitivity.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01611194; https://clinicaltrials.gov/show/NCT01611194.

Systematic analysis of clinical deficits in unilateral hypoglossal nerve palsy

INTRODUCTION

The clinical characteristics of unilateral hypoglossal neuropathy have not been systematically analyzed.

METHODS

We documented subjective abnormalities of speech and swallowing, and photographed 9 specific tongue movements and positions. Objective deficits were scored independently by 2 examiners.

RESULTS

Eight patients were analyzed. Some degree of dysarthria and dysphagia was noticed by 7 and 8 patients, respectively, mostly resolving within a few months. In all subjects, there was contralateral deviation of the tongue at rest and ipsilateral deviation upon forward protrusion. Furthermore, 7 of 8 patients had deficits in using the tongue to indent the ipsilateral cheek and cover the upper lip.

CONCLUSIONS

Unilateral hypoglossal nerve palsy produces mostly subtle and transient patient symptoms, even when complete. Beyond the classic sign of ipsilateral deviation on protrusion, reliable signs are contralateral deviation at rest, paresis of ipsilateral movement inside the mouth, and paresis of elevation of the tongue tip. Muscle Nerve 54: 1055-1058, 2016.

Neurological Development of Children With Isolated Robin Sequence Treated With Nasopharyngeal Intubation in Early Infancy

The study assessed the neurodevelopment of children with isolated Robin sequence (IRS) and evaluated if children treated exclusively with nasopharyngeal intubation (NPI) present delay in neurological development. The prospective and cross-sectional study was conducted at the Hospital for Rehabilitation of Craniofacial Anomalies, Brazil. Children with IRS were divided into two groups according to the type of treatment in early infancy: 38 were treated with NPI (more severe cases) and 24 with postural treatment (less severe cases). Regarding interventions, children were assessed at 2 to 6 years of age using the Denver II Developmental Screening Test (Denver II) and Neurological Evolutionary Examination (NEE). According to Denver II, 73.7% in the NPI group and 79.2% in the postural group presented normal development. This result was similar to the results of different studies in the literature with typical population. Considering all areas of development, there were no significant differences in Denver II between the NPI and postural groups (P = .854). In the NPI group, 89.5% of children and 87.5% in the postural group presented normal development in NEE. Language was the most affected area, as 18.4% and 20.8% of children in NPI and postural group, respectively, presented risk for delay in the Denver II. The increased risk for delay in language area was probably due to anatomical conditions of the muscles involved in speech, and to hearing oscillations, as 47.4% in NPI group and 58.3% in postural group underwent myringotomy. IRS treated with NPI had neurological development similar to those in less severe cases. Children treated exclusively with NPI did not present delay in neurological development.

Prenatal ultrasound evaluation of segmental level of neurological lesion in fetuses with myelomeningocele: development of a new technique

OBJECTIVES

To report our preliminary experience in the use of prenatal ultrasound examination to assess lower-limb movements in fetuses with myelomeningocele. We aimed to determine the accuracy of this method to establish the segmental level of neurological lesion, as this is the best known predictor of the future ability to walk.

METHODS

This was a preliminary, observational study including fetuses with myelomeningocele operated on prenatally. The patterns of movements present and absent in the affected fetuses' lower limbs were evaluated systematically by ultrasound examination. According to the known nerve function associated with each muscle group, the segmental level of neurological lesion was established before birth. The agreement for the segmental levels assigned, between the prenatal ultrasound technique and the classical neurological clinical examination after birth (gold standard), was tested using the weighed kappa (wκ) index.

RESULTS

Seventy-one fetuses with myelomeningocele were evaluated at the Hospital Universitari Vall d'Hebron. After counseling, the parents opted for prenatal surgery (26 cases), termination of pregnancy (43 cases) or postnatal repair (two cases). Five patients did not fulfil the inclusion criteria for prenatal surgery and three were excluded after birth. In the 18 fetuses that underwent surgery and were analyzed, the agreement between prenatal and postnatal segmental levels assigned was 91.7% for the right limb (wκ = 0.80) and 88.9% for the left limb (wκ = 0.73).

CONCLUSIONS

The agreement found between prenatal and postnatal assignment of level of lesion in this preliminary study suggests that neurological sonographic evaluation is feasible before birth. This may provide accurate individualized information about the motor function and future ambulation prognosis of fetuses with myelomeningocele.

The Under-Utilization of the Head Impulse Test in the Emergency Department

BACKGROUND

The head impulse test (HIT) is an evidenced based clinical tool to differentiate between peripheral and central causes of vertigo. Our objective was to determine the rate of utilization of the HIT in the emergency room (ER).

METHODS

A retrospective chart review of patients presenting to the ER over one year who received a final diagnosis of dizziness or vertigo. Details of clinical examinations, investigations, and diagnosis were recorded. Patients were grouped into episodic, acute constant, and chronic vertigo groups.

RESULTS

HIT was performed in only 31 of 642 (5%) patients with vertigo. In the acute constant group it was negative in 6 of 6 patients ultimately diagnosed with stroke and positive in 6 of 13 cases of peripheral vertigo.

DISCUSSION

Despite good published evidence regarding its use the HIT is under-utilized in the ER. Physicians need to be aware of the HIT and newer video HITs and make use of them in practice.

Neglect and extinction in kinesthesia and thesesthesia: understanding proprioceptive inattention

This paper describes a new observation of neglect and extinction of kinesthesia and thesesthesia (movement and position imperception), jointly reflecting proprioceptive inattention, in a series of patients with parietal lesions. A prototypical case is discussed in detail and unaddressed aspects of proprioceptive inattention are discussed through findings from four additional cases. Thesesthetic and kinesthetic extinction were tested through simultaneous antidromic vertical displacement of index fingers, while having patients report on finger proprioceptive perception with eyes closed. Patients had variable degrees of proprioceptive inattention affecting a specific limb, but without pallesthetic inattention or somatoagnosia, whereas symptoms often resolved with visual feedback or active limb movements. Findings support that kinesthesia and thesesthesia (a) are subserved by near-identical brain networks, (b) relate more to tactile perception than pallesthesia in higher order cortical areas, and (c) have a somatotopic cortical organization even in association brain areas. Furthermore, proprioceptive extinction and neglect involve (i) "attention network" structures, (ii) either hemisphere, (iii) gray or subcortical white matter damage, (iv) defective vigilance mechanisms possibly through premature habituation of spatiotemporally saturated neural capacitor circuits, and (v) are not the result of somatoagnosia, while (vi) their resolution is observed through reafferent motor-sensory or visual feedback.

National survey of UK medical students on the perception of neurology

BACKGROUND

Medical students perceive neurology to be a difficult subject, a phenomenon described as "neurophobia". Studies investigating student attitudes towards neurology have so far been limited by small sample sizes as a consequence of being conducted within a single medical school or region. We aimed to conduct the first national survey of the perception of neurology among UK medical students.

METHODS

A 24 question online survey was designed and distributed in the form of a web-link to all UK medical schools. Responses were collected for 10 weeks with reminders sent at 3 and 6 weeks. A prize-draw of £300 was offered upon completion of the survey.

RESULTS

2877 medical students from 25 of 31 medical schools responded. Students found neurology to be significantly more difficult than other specialties and were least comfortable drawing up a neurological differential diagnosis compared to other specialties (p < 0.0001 for neurology vs. each of the other specialties). Neuroanatomy was regarded as the most important factor contributing to neurology being perceived as difficult.

CONCLUSIONS

The findings of the first national survey addressing this issue are consistent with previous research. The perception of neurology remains unchanged, in contrast to the rapidly changing demands of neurological care in an ageing population. Neurological examination and formulating a differential diagnosis are important skills in any medical specialty, and combatting "neurophobia" in medical students is therefore essential.

Abnormal downward gaze and cold caloric examination due to propofol: a case study

BACKGROUND

An adolescent girl had isolated abnormal downward gaze and oculovestibular (cold caloric) testing during propofol administration, prompting concern for brainstem abnormality.

PATIENT

An otherwise healthy 16-year-old girl presented after an intentional hanging. Brainstem reflexes were normal except that both eyes exhibited tonic downward gaze on initial examination. After propofol was suspended for 30 minutes in order to evaluate her level of responsiveness, her eyes normalized to midposition from tonic downward gaze. With reinitiation of propofol, the eyes returned to the former downward position. C-collar stabilization prohibited the usual oculocephalic (doll's eyes) evaluation. Right-sided cold water instillation resulted in right eye exodeviation to the right with minimal medial movement of the left eye to the right. After left-sided cold water instillation, the left eye deviated downward with minimal medial deviation of the right eye. She was extubated and off sedatives within 48 hours of admission, and normal ocular motility returned.

CONCLUSION

This patient exhibited abnormal ocular motility and cold caloric response with single-agent propofol exposure. The remainder of her cranial nerve examination was normal, and her normal imaging studies and prompt resolution led us to suspect a propofol effect. Physicians should be aware of the pharmacologic alterations of ocular motility and cold caloric testing when propofol is administered.