Restless legs syndrome mimicking S1 radiculopathy.

Α case of a chronic idiopathic form of a severe type of Restless Legs Syndrome (RLS), which developed during pregnancy and persisted after this, misdiagnosed for 34 years as radiculopathy S1, is reported. In spite of the thorough clinical and laboratory investigation, in addition to constant changes of the therapeutic approach, the diagnosis of S1 radiculopathy could not be confirmed, resulting in a chronic clinical course; the latter was characterized by relapses and remissions not attributed or linked in any way to the treatment (various types of). In fact, it was due to a routine workup in a sleep clinic, where the patient was referred because of a coincident chronic insomnia (Restless Legs Syndrome is a known and important cause of insomnia/chronic insomnia), which resulted in a proper diagnosis and treatment of this case. With the use of Restless Legs Syndrome appropriate treatment (Pramipexole 0.18 mg taken at bedtime, a dopaminergic agent and Level A recommended drug for Restless Legs Syndrome) an excellent response and immediate elimination of symptoms was achieved. Restless Legs Syndrome may present with a variety of symptoms (with the most prominent shortly being reported with the acronym URGE: Urge to move the legs usually associated with unpleasant leg sensations, Rest induces symptoms, Getting active brings relief, Evening and night deteriorate symptoms); given the fact that Restless Legs Syndrome presents with a great variety and heterogeneity of symptoms (mostly pain, dysesthesia and paresthesia), which may occur in several other diseases (the so called "RLS mimics"), proper diagnosis of Restless Legs Syndrome usually fails. Restless Legs Syndrome misinterpreted as S1 radiculopathy, to the best of our knowledge, has not been reported yet in the literature. Here, case history, clinical course and common RLS mimics are presented. Different forms of Restless Legs Syndrome manifestations, which are commonly -as in this case- misinterpreted due to their mimicking several pathological conditions, Restless Legs Syndrome prevalence on general population according to various large epidemiological studies and pathogenic hypotheses on the issue of Restless Legs Syndrome are discussed. Finally, by presenting another possible "RLS-mimic" our aim is to highlight the common misdiagnosis of Restless Legs Syndrome, which can mimic a variety of disorders, some of which are very common, such as an S1 radiculopathy, thus raising concern among doctors of various specialties addressed to by Restless Legs Syndrome sufferers, on the importance of proper diagnosis of the syndrome.

Association between the Epworth sleepiness scale and the multiple sleep latency test in a clinical population.

BACKGROUND: Excessive daytime sleepiness can be evaluated with both subjective and objective tests. OBJECTIVE: To examine the association between Epworth Sleepiness Scale scores and sleep latency on the multiple sleep latency test. DESIGN: Case series. SETTING: Referral sleep disorders center. PATIENTS: 102 consecutive patients evaluated for excessive daytime sleepiness. MEASUREMENTS: Epworth Sleepiness Scale scores and mean sleep latency on the multiple sleep latency test. RESULTS: No significant association was seen between Epworth scores and mean sleep latency (Pearson correlation, -0.17 [95% CI, -0.35 to 0.03]; P = 0.09) (analysis of variance, P = 0.13). The mean Epworth score did not differ in three groups of patients who were defined by mean sleep latency as having normal sleep latency (>10 minutes), moderate sleep latency (5 to 10 minutes), or severe sleep latency (<5 minutes) (analysis of variance, P = 0.13). CONCLUSIONS: No statistically or clinically significant association was seen between Epworth scores and mean sleep latency. The subjective Epworth Sleepiness Scale and the objective multiple sleep latency test may evaluate different, complementary aspects of sleepiness.

Staring spells in children: descriptive features distinguishing epileptic and nonepileptic events.

OBJECTIVE: To identify questions sensitive and specific for staring spells of epileptic (absence seizures [AS]) or nonepileptic etiology to increase the yield of history taking. STUDY DESIGN: A questionnaire was completed by parents of 40 children who presented with staring spells. Results from 17 children with AS and 23 with nonepileptic staring (NES) were compared. RESULTS: Features with moderate sensitivity (43% to 56%) but high specificity (87% to 88%) for NES included preserved responsiveness to touch, lack of interruption of playing, and initial identification by a teacher or health professional. These features were more frequent in NES than in AS (P = .013, .016, .030). Body rocking occurred only in NES, but sensitivity was low (13%). Features with high specificity (91% to 100%) for AS included limb twitches, upward eye movements, and urinary incontinence; but sensitivities were low (13% to 35%). CONCLUSION: In children with normal interictal electroencephalography findings and without neurologic disease, staring spells are most likely nonepileptic when parents report preserved responsiveness to touch, body rocking, or initial identification by a teacher or health professional without limb twitches, upward eye movements, interruption of play, or urinary incontinence. In these cases a diagnosis of NES may be confidently applied, with confirmation based on long-term follow-up.

Histopathological correlates of epileptogenicity as expressed by electrocorticographic spiking and seizure frequency.

PURPOSE: To study the correlation between histopathology and epileptogenicity, as measured by seizure frequency and electrocorticography (EcoG), in patients with cortical dysplasia (CD) as compared with control patients with gangliogliomas or gliomas. METHODS: The influence of the histopathological classification and the presence of balloon cells in CD on the frequency and extension of five predefined patterns of ECoG spiking, seizure frequency, age of seizure onset and 6-month postoperative outcome were analyzed in 32 patients with focal epilepsy undergoing presurgical evaluation with chronically implanted subdural electrodes. RESULTS: Comparison of patients with CD, gangliogliomas, and gliomas showed that the seizure frequency was greatest in patients with CD and ECoG spiking and was most extensive in patients with gangliogliomas. The onset of epilepsy was earlier in patients with CD and with gangliogliomas. None of these differences was significant. However, in patients with CD, the presence of balloon cells was associated with significantly greater seizure frequency (p=0.009), and a significantly greater number of electrodes recording continuous frequent spiking (p=0.03). The presence of continuous very frequent spiking correlated with the duration of the epilepsy and the number of seizures recorded during monitoring. No significant correlation was detected between histopathology, seizure frequency, or ECoG activity and postoperative outcome, which was relatively favorable in patients with balloon cells. CONCLUSIONS: CD refers to a variety of histopathological patterns associated with different epileptogenicity. In CD, increased clinical and ECoG epileptogenicity correlates with the presence of balloon cells. This finding confirms that balloon cells should be considered in the histopathological classification of CD. The predefined ECoG were not specific for any of the histopathologies investigated.

Value of full-field visual evoked potentials for retrochiasmal lesions.

Some abnormalities in the P100 on monocular stimulation have been said to indicate retrochiasmal abnormalities. This study was undertaken to evaluate the reliability of visual evoked potentials (VEPs) for this purpose. We retrospectively reviewed VEPs that could be interpreted as indicative of a retrochiasmal lesion, based on an amplitude asymmetry of >50% between the P100 recorded on the left and right occipital regions. The abnormality had to be present on both left and right monocular stimulation (uncrossed pattern). Studies were conducted in accordance with the guidelines of the American Electroencephalographic Society. Findings on magnetic resonance (MR) imaging were analyzed. For comparison, we also studied a control group of 30 patients with normal VEPs. During a 16-month period, we identified 15 patients who fulfilled the aforementioned criteria and who had undergone an MR scan of the brain. Eight scans were normal and seven were abnormal. Of the seven abnormal scans, five revealed multiple periventricular white matter lesions in both hemispheres suggestive of multiple sclerosis: one a single punctate white matter lesion in the left frontal corona radiata, and one multiple white matter lesions in the basal ganglia, brainstem, and cerebellum but not in the hemispheres. In the control group with normal VEPs, nine had at least one hemispheric lesion on MR scans. This yielded a positive predictive value of 33%. The negative predictive value was 70%, sensitivity 36%, and specificity 68%. Because of a high rate of false positives, full-field VEPs were not reliable in predicting retrochiasmal lesions.

The multiple sleep latency test: comparison of sleep onset criteria.

Determining sleep latency is one of the cornerstones of the interpretation of the multiple sleep latency test (MSLT). The purpose of this study was to compare various criteria used to determine sleep onset. We prospectively analyzed 100 consecutive MSLTs that were performed according to a standardized protocol. We scored each test using three separate sets of criteria for sleep onset: 1) one epoch of stage 1 sleep, 2) two consecutive epochs of stage 1 sleep, and 3) three consecutive epochs of stage 1 sleep. Each method yielded a mean sleep latency and a categorical classification of the record as normal if > 10 minutes, moderate if > or = 5 and < or = 10 minutes, and severe sleepiness if < 5 minutes. The ages of participants ranged from 4 to 78 years (mean 45.5). The averages of the mean sleep latencies across all three methods were: 6.2 minutes [standard deviation (SD) = 4.3] using one epoch, 7.2 minutes (SD = 4.7) using two epochs, and 7.5 minutes (SD = 4.9) using three epochs. Using the three categories of sleepiness, the implementation of the three-epoch criterion vs. the one-epoch criterion produced a change in category in 16 patients (16%). Five went from severe to moderate, 10 from moderate to normal, and 1 from severe to normal. As compared to using one epoch, using three produced an increase in mean sleep latency of at least 50% in 13 patients. The use of various criteria for sleep onset, especially criteria 1 and 3 above, produces differences in interpretation that are neither rare nor quantitatively negligible. Standardization of the methodology across centers would be desirable in clinical practice as well as for research protocols.

Value of tongue biting in the diagnosis of seizures.

BACKGROUND: Seizures are rarely witnessed by physicians, and the diagnosis is usually made on the basis of the history. Tongue biting is classically considered to favor a diagnosis of epileptic seizure. The usefulness of tongue biting in the differential diagnosis of seizures was evaluated. METHODS: A prospective study of the presence of oral lacerations in 106 consecutive patients admitted to our Epilepsy Monitoring Unit and a retrospective study of a population of 45 patients with syncope were performed. The relationship between tongue biting and diagnosis (epileptic vs nonepileptic events) was analyzed. RESULTS: Of the 106 monitored patients, 63 had episodes characterized by bilateral motor activity, complete loss of consciousness, or both; 34 patients had epileptic seizures, while 29 patients had exclusively nonepileptic episodes. Eight patients suffered an oral laceration; all involved the side of the tongue, and all had documented epileptic seizures. Of the 45 patients with syncope, in only one was the tongue lacerated, and this was at the tip. Tongue biting had a sensitivity of 24% and a specificity of 99% for the diagnosis of generalized tonic-clonic seizures. Lateral tongue biting was 100% specific to grand mal seizures. CONCLUSION: Tongue biting, particularly if it is lateral, is highly specific to generalized tonic-clonic seizures.

Mean versus median for the multiple sleep latency test.

Since its introduction in the mid-1970s, the multiple sleep latency test (MSLT) has become the standard method for evaluating hypersomnolence. The mean sleep latency is usually calculated and constitutes the traditional basis for interpretation. Mean and median are both measures of the central tendency of a distribution, but because the trials of the MSLT are limited to 20 minutes, the median may be more appropriate. The objective of this study was to compare the value of the mean versus the median sleep latency in the interpretation of the MSLT. We retrospectively analyzed 100 MSLTs performed for evaluation of excessive daytime sleepiness. Patients' ages ranged from 6 to 84 years (mean 43). Mean and median sleep latencies were calculated according to standard formulas. We classified each record into one of three categories, using both the mean and the median sleep latencies: normal (> 10 minutes), moderate (> or = 5 and < or = 10 minutes), and severe sleepiness (< 5 minutes). Of the 100 MSLTs, 89 remained in the same category (normal, moderate, severe) whether mean or median was used. In 11 cases, the category changed. All shifts were by one category, that is, no shift occurred between normal and severe. This study suggests that, despite valid theoretical arguments for the use of the median, both measures are equally acceptable for clinical purposes.

Dreams and rapid eye movement sleep in the multiple sleep latency test.

Dreams are closely associated with rapid eye movement (REM) sleep. The purpose of this study was to evaluate the reliability of dreams in predicting the presence of REM sleep during naps of the multiple sleep latency test (MSLT). We prospectively analyzed MSLTs performed in the evaluation of 44 patients with excessive daytime sleepiness. A total of 167 naps were studied. The patients' ages ranged from 11 to 69 years (mean 45 years). There were 26 males and 18 females. The relationship between the presence of reported dreams and the presence of REM sleep was as follows: sensitivity (percentage of naps with REM in which dreams were reported), 59%; specificity (percentage of naps without REM in which no dreams were reported), 63%; positive predictive value (probability that REM occurred if dreaming is present), 29%; and negative predictive value (probability that REM did not occur when no dreaming is present), 85%. In the daytime naps of the MSLT, the presence of reported dreaming did not appear to be a reliable indicator of the presence of REM sleep in the preceding nap.