Faculty Bibliography

BACKGROUND: Based upon scarce clinical data in humans and experimental findings in animal studies, it has been postulated that the ascending gustatory projection from the nucleus tractus solitarii courses ipsilaterally through the pons and midbrain to the ipsilateral ventral posteromedial nucleus. Thus, it has been assumed that ischemic lesions affecting the secondary projection gustatory fibers would cause ipsilateral taste disorders. DESCRIPTION OF CASE: We report a case of bilateral ageusia following an acute right midbrain and thalamic infarction affecting the ipsilateral central trigeminal tract and ventral posteromedial nucleus in a right-handed man. CONCLUSION: The present case indicates that, in contrast to animal data, some secondary projection gustatory fibers may cross in humans and consequently unilateral right-sided posterior circulation ischemic lesions can cause bilateral gustatory deficits.

OBJECTIVE: To determine whether weight gain is associated with recurrence in idiopathic intracranial hypertension (IIH). METHODS: Medical records of adult patients with IIH seen between 1993 and 2009 at 2 university hospitals were reviewed to identify those with and without recurrence. Patients with documented height and weight at presentation and at subsequent visits were studied. The Wilcoxon rank sum test was used to compare mean body mass index (BMI) and percent weight change between the groups of patients with recurrence and without recurrence. The signed-rank test was used for comparing BMI within groups at the various time points. RESULTS: Fifty women with IIH were included in the analyses: 26 had IIH recurrence and 24 did not. Patients with recurrence had greater BMI at the time of recurrence compared to BMI at diagnosis (p = 0.02, signed-rank test). They also demonstrated a greater degree of weight gain between initial resolution and recurrence (BMI change +2.0 kg/m(2) [-1.5 to 10.8]) compared to patients without recurrence (-0.75 kg/m(2) [-35 to 3.6], p = 0.0009, Wilcoxon rank sum test). Patients without recurrence demonstrated stable weights (0%[95% CI -9.6 to 10.1%]), while patients with recurrence demonstrated a 6% weight gain ([-3.5 to 40.2%], p = 0.005), with an average rate of BMI gain of 1.3 kg/m(2)/year vs -0.96 kg/m(2)/year in those without recurrence. CONCLUSION: Patients with IIH recurrence had significant increases in BMI compared to patients without recurrence in this cohort. Patients with resolved IIH should be advised that weight gain may be a risk factor for IIH recurrence.

OBJECTIVE: Sports-related concussion has received increasing attention as a cause of short- and long-term neurologic symptoms among athletes. The King-Devick (K-D) test is based on measurement of the speed of rapid number naming (reading aloud single-digit numbers from 3 test cards), and captures impairment of eye movements, attention, language, and other correlates of suboptimal brain function. We investigated the K-D test as a potential rapid sideline screening for concussion in a cohort of boxers and mixed martial arts fighters. METHODS: The K-D test was administered prefight and postfight. The Military Acute Concussion Evaluation (MACE) was administered as a more comprehensive but longer test for concussion. Differences in postfight K-D scores and changes in scores from prefight to postfight were compared for athletes with head trauma during the fight vs those without. RESULTS: Postfight K-D scores (n = 39 participants) were significantly higher (worse) for those with head trauma during the match (59.1 +/- 7.4 vs 41.0 +/- 6.7 seconds, p < 0.0001, Wilcoxon rank sum test). Those with loss of consciousness showed the greatest worsening from prefight to postfight. Worse postfight K-D scores (r(s) = -0.79, p = 0.0001) and greater worsening of scores (r(s) = 0.90, p < 0.0001) correlated well with postfight MACE scores. Worsening of K-D scores by >/=5 seconds was a distinguishing characteristic noted only among participants with head trauma. High levels of test-retest reliability were observed (intraclass correlation coefficient 0.97 [95% confidence interval 0.90-1.0]). CONCLUSIONS: The K-D test is an accurate and reliable method for identifying athletes with head trauma, and is a strong candidate rapid sideline screening test for concussion.

Multiple sclerosis (MS) is the quintessential neurologic disorder from which to understand the principles of afferent and efferent neuro-ophthalmology. Perhaps with the exception of stroke, no other disorder is associated with nearly every sign and symptom of abnormalities targeting the visual system and the ocular motor apparatus. This focused review will underscore the most common syndromes and their derivative signs and symptoms that affect vision as a consequence of MS.

OBJECTIVE: Cross-sectional studies of optical coherence tomography (OCT) show that retinal nerve fiber layer (RNFL) thickness is reduced in multiple sclerosis (MS) and correlates with visual function. We determined how longitudinal changes in RNFL thickness relate to visual loss. We also examined patterns of RNFL thinning over time in MS eyes with and without a prior history of acute optic neuritis (ON). METHODS: Patients underwent OCT measurement of RNFL thickness at baseline and at 6-month intervals during a mean follow-up of 18 months at 3 centers. Low-contrast letter acuity (2.5%, 1.25% contrast) and visual acuity (VA) were assessed. RESULTS: Among 299 patients (593 eyes) with >or=6 months follow-up, eyes with visual loss showed greater RNFL thinning compared to eyes with stable vision (low-contrast acuity, 2.5%: p < 0.001; VA: p = 0.005). RNFL thinning increased over time, with average losses of 2.9microm at 2 to 3 years and 6.1microm at 3 to 4.5 years (p < 0.001 vs 0.5-1-year follow-up interval). These patterns were observed for eyes with or without prior history of ON. Proportions of eyes with RNFL loss greater than test-retest variability (>or=6.6microm) increased from 11% at 0 to 1 year to 44% at 3 to 4.5 years (p < 0.001). INTERPRETATION: Progressive RNFL thinning occurs as a function of time in some patients with MS, even in the absence of ON, and is associated with clinically significant visual loss. These findings are consistent with subclinical axonal loss in the anterior visual pathway in MS, and support the use of OCT and low-contrast acuity as methods to evaluate the effectiveness of putative neuroprotection protocols.

We report two patients, both with a history of gastric surgery, who presented with progressive optic neuropathy and myelopathy. The patients' symptoms were initially attributed to vitamin B12 deficiency and/or neuromyelitis optica; however, after the neurologic deficits continued to progress with the use of conventional treatments, further evaluation was initiated, and a severe copper deficiency was revealed. Copper deficiency is a rare cause of progressive optic neuropathy and myelopathy and should be considered in the differential diagnosis. It is crucial to elicit a history of gastric surgery or other risk factors for hypocupremia in those patients undergoing an evaluation for subacute or chronically progressive optic neuropathy or myelopathy.

BACKGROUND: Patient nonattendance in neurology and other subspecialty clinics is closely linked to longer waiting times for appointments. We developed a new scheduling system for residents' clinic that reduced average waiting times from >4 months to < or =3 weeks. The purpose of this study was to compare nonattendance for clinics scheduled using the new model (termed "rapid access") vs those scheduled using the traditional system. METHODS: In the rapid access system, nonestablished (new) patients are scheduled on a first-come, first-served basis for appointments that must occur within 2 weeks of their telephone request. Nonattendance for new patient appointments (cancellations plus no-shows) was compared for patients scheduled under the traditional vs the rapid access scheduling systems. Nonattendance was compared for periods of 6, 12, and 18 months following change in scheduling system using the chi2 test and logistic regression. RESULTS: Compared to the traditional scheduling system, the rapid access system was associated with a 50% reduction in nonattendance over 18 months (64% [812/1,261 scheduled visits] vs 31% [326/1,059 scheduled visits], p < 0.0001). In logistic regression models, appointment waiting time was a major factor in the relation between rapid access scheduling and nonattendance. Demographics, diagnoses, and likelihood of scheduling follow-up visits were similar between the 2 systems. CONCLUSIONS: A new scheduling system that minimizes waiting times for new patient appointments has been effective in substantially reducing nonattendance in our neurology residents' clinic. This rapid access system should be considered for implementation and will likely enhance the outpatient educational experience for trainees in neurology.

Patients with multiple sclerosis commonly describe visual symptoms that result from several eye movement abnormalities that occur from disruption of critical pathways in the brainstem, cerebellum, and cerebral hemispheres. These abnormalities include internuclear ophthalmoplegia, ocular motor palsy, ocular misalignment, pathologic nystagmus, impaired saccades, saccadic intrusions, and impaired pursuit. Detailed knowledge of these problems and their neuroanatomic localization will aid the physician by guiding diagnosis and therapeutic decision making.