Small Fiber Neuropathy Associated with Hyperlipidemia: Utility of Cutaneous Silent Periods and Autonomic Tests

Background. Established electrophysiological methods have limited clinical utility in the diagnosis of small fiber neuropathy. The cutaneous silent period (CSP) may be useful as a method for the evaluation of smaller and unmyelinated fiber dysfunctions. Hyperlipidemia is a very rare cause of small fiber neuropathy. In this study, hyperlipidemia and small fiber neuropathy in symptomatic patients with normal nerve conduction studies were evaluated with autonomic tests and cutaneous silent periods. Methods. Twenty-five patients with clinically suspected small fiber neuropathy and 23 healthy volunteers were included. CSP latency and duration, as well as CSP latency difference of the upper and lower extremities, were examined. Two tests were used to assess the autonomic nervous system, namely, the R-R interval variation test in basal and profound breath conditions and the sympathetic skin response. Results. Twenty-five patients with clinically suspected small fiber neuropathy and normal nerve conduction studies were compared with 23 controls. In the upper extremities, patients had prolonged CSP latencies (P=0.034) and shortened CSP durations (P=0.039), whereas in the lower extremities, patients had shortened CSP durations (P=0.001). The expiration-to-inspiration ratios were also reduced in patients groups. There was no significant difference between sympathetic skin response latencies and amplitude of the case and control groups. Conclusion. Our findings indicate that CSP may become a useful technique for the assessment of small fiber neuropathy in hyperlipidemic patients.

Cognitive Impairment in Relapsing Remitting and Secondary Progressive Multiple Sclerosis Patients: Efficacy of a Computerized Cognitive Screening Battery

Objective. To investigate the pattern of cognitive impairment in relapsing remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS) patients using a computerized battery. Methods. RRMS patients N=50, SPMS patients N=30, and controls N=31 were assessed by Central Nervous System Vital Signs (CNS VS) computerized battery, Trail Making Tests (TMT) A and B, and semantic and phonological verbal fluency tasks. Results. The overall prevalence of cognitive dysfunction was 53.75% (RRMS 38%, SPMS 80%). RRMS patients differed from controls with large effect size on reaction time, medium effect size on TMT A and small on TMT B, phonological verbal fluency, composite memory, psychomotor speed, and cognitive flexibility. SPMS patients differed from controls in all neuropsychological measures (except complex attention) with large effect sizes on TMT A and B, phonological verbal fluency, composite memory, psychomotor speed, reaction time, and cognitive flexibility. Between patient groups, medium effect sizes were present on TMT B and psychomotor speed, while small effect sizes were present on composite memory and processing speed. Conclusion. CNS VS is sensitive in detecting cognitive impairment in RRMS and SPMS patients. Significant impairment in episodic memory, executive function, and processing speed were identified, with gradual increment of the frequency as disease progresses.

Minimizing Technical Failure of Percutaneous Balloon Compression for Trigeminal Neuralgia Using Neuronavigation

Objective. Percutaneous balloon compression (PBC) is an effective and safe management for medically refractory trigeminal neuralgia; however, technical failure to cannulate the foramen ovale (FO) using only fluoroscopy is a significant problem in some cases. In this paper, we suggest the use of intraoperative navigation, in cases of reoperation due to prior technical failure to cannulate the FO under fluoroscopy. Methods. A total of 174 patients underwent PBC for TN since 2003. In 9 cases the penetration of the FO was not accomplished. Five of those patients were reoperated on for PBC using navigation from March 2012 to September 2012. Surgical technique: preoperatively, a head Computed Tomography (CT) scan is performed and the acquired images are imported into the navigation system. Intraoperatively, a small reference frame is strapped firmly to the patient’s forehead, the CT images are registered, and cannulation is performed under the guidance of the navigation system. Results. In all patients, the operation overall was completed successfully. Moreover, all patients reported complete pain relief immediately postoperatively and no complications were recorded overall. Conclusions. We suggest the use of neuronavigation in cases of technical failure of PBC. That technique involves technology with significant advantages helping the successful cannulation of the FO and seems more efficient and safer.

Nonmotor Symptoms in Early- and Advanced-Stage Parkinson’s Disease Patients on Dopaminergic Therapy: How Do They Correlate with Quality of Life?

To determine the impact of nonmotor symptoms (NMS) on health-related quality of life (HRQoL) we examined 100 Parkinson’s disease (PD) patients on dopaminergic medications. An “early-stage” (ES) and an “advanced-stage” (AS) groups were formed. HRQoL was established by the questionnaire PDQ-8, number of NMS by NMSQuest, and severity and frequency of NMS by the assessment scale NMSS. The total NMS averaged 11.3 (ES=9.6, AS=12.8). The NMSS domain correlation profiles for ES and AS did not fundamentally differ; however, the domains attention/memory and mood/apathy correlated moderately to strongly with HRQoL in ES, while the sleep/fatigue domain correlated moderately with HRQoL in AS. Weakly correlating domains were sleep/fatigue in ES and cardiovascular, attention/memory, and mood/apathy domains in AS. In view of these findings we strongly recommend systematic, active screening and therapy for neuropsychiatric disorders (mood, cognitive and sleep disorders, and fatigue) at the initial diagnosis and throughout the entire course of PD.

Evaluating Different Aspects of Prospective Memory in Amnestic and Nonamnestic Mild Cognitive Impairment

Prospective memory, the inability to remember an intended action, is a common complaint, but not formally assessed in most clinical and research studies of mild cognitive impairment (MCI). In this study, patients with amnestic mild cognitive impairment (aMCI), non-amnestic cognitive impairment (naMCI), and cognitively normal (CN) elders were assessed using the Miami Prospective Memory Test (MPMT). A unique aspect of the paradigm was that participants were scored for intention to perform, accuracy in recollection for specific elements of the task, and the need for reminder cues. Excellent test-retest stability was obtained for MPMT Event-Related (ER), combined Time-Related (TR) subscales, and total MPMT score for aMCI subjects. MPMT impairments were observed in 48.6% of aMCI, 29.4% of naMCI, and 10.0% of normal elderly participants. Prospective memory deficits were common in participants with aMCI, and occurred in almost a third of naMCI participants. Intention to perform and need for reminder cues were significantly more impaired than retrospective memory for specific details of the task. It is concluded that assessment of different elements of prospective memory is important in MCI research and that inability to remember intended actions is a significant feature in those as risk for Alzheimer’s disease.

Urinary Catheterization May Not Adversely Impact Quality of Life in Multiple Sclerosis Patients

Background. Multiple sclerosis (MS) healthcare providers (HCP) have undergone considerable educational efforts regarding the importance of evaluating and treating pelvic floor disorders, specifically, urinary dysfunction. However, limited data are available to determine the impact of catheterization on patient quality of life (QoL). Objectives. To describe the use of urinary catheterization among MS patients and determine the differences between those who report positive versus negative impact of this treatment on QoL. Methods. Patients were queried as part of the 2010 North American Research Committee On Multiple Sclerosis survey; topics included 1) urinary/bladder, bowel, or sexual problems; 2) current urine leakage; 3) current catheter use; 4) catheterizing and QoL. Results. Respondents with current urine leakage were 5143 (54.7%), of which 1201 reported current catheter use (12.8%). The types of catheters (intermittent self-catheterization and Foley catheter (indwelling and suprapubic)) did not differ significantly. Of the current catheter users, 304 (25.35%) respondents reported catheterization negatively impacting QoL, 629 (52.4%) reported a positive impact on QoL, and 223 (18.6%) reported neutral QoL. Conclusions. A large proportion of catheterized MS patients report negative or positive changes in QoL associated with urinary catheterization. Urinary catheterization does not appear to have a universally negative impact on patient QoL.

Minicraniotomy for Standard Temporal Lobectomy: A Minimally Invasive Surgical Approach

Introduction. The common surgical approach for standard temporal lobectomy is a question-mark skin incision and a frontotemporal craniotomy. Herein, we describe minicraniotomy approach through a linear skin incision for standard temporal lobectomy. Methods. A retrospective observational cohort study was conducted for a group of consecutive 21 adult patients (group I) who underwent minicraniotomy for standard temporal lobectomy utilizing a linear skin incision. This group was compared to a consecutive 17 adult patients (group II) who previously underwent a reverse question-mark skin incision and standard frontotemporal craniotomy. Results. The mean age was 29 and 23 for groups I and II, respectively. The mean estimated blood loss was 190 mL and 280 mL in groups I and II, respectively (P=0.019). Three patients in group II developed chronic postcraniotomy headache compared to none in group I. Cosmetic outcome was excellent in group I while 4 patients in group II developed disfiguring depression at lateral sphenoid wing and anterior temple. In group I 17 out of 21 became seizure-free at one-year followup. Conclusion. Minicraniotomy through a linear skin incision is a sufficient surgical approach for effective standard temporal lobectomy and it has an excellent cosmetic outcome.

Serotonin Transporter Availability in Early Stage Parkinson’s Disease and Multiple System Atrophy

Background. Differentiating Parkinson’s disease (PD) from multiple system atrophy (MSA) can be challenging especially early in the course of the disease. Previous studies have shown that midbrain serotonin transporter (SERT) availability in patients with established MSA was significantly lower compared to PD. It is unknown if this is also true for early-stage patients. Methods. 77 early-stage, untreated PD patients were recruited between 1995 and 1998, underwent [123I]β-CIT SPECT imaging, and were followed for at least five years. 16 patients were lost to followup, and in 4 the diagnosis was changed to another atypical parkinsonian syndrome, but not in MSA. In 50 patients, the PD diagnosis was unchanged at followup. In seven patients, the diagnosis was changed to MSA at followup. We retrospectively assessed baseline midbrain SERT availability as well as midbrain SERT-to-striatal dopamine transporter (DAT) ratios. Results. No difference in baseline [123I]β-CIT SERT availability was found. The midbrain SERT-to-striatal DAT ratio for whole striatum was significantly lower in patients with PD compared to MSA (P=0.049). However, when adjusting for the disease duration at imaging this difference is not significant (P=0.070). Conclusion. Midbrain SERT availability is not different between early-stage PD and MSA. Therefore, SERT imaging is not useful to differentiate between early PD and MSA.

Continuous Spike-Wave during Slow Wave Sleep and Related Conditions

Continuous spike and wave during slow wave sleep (CSWS) is an epileptic encephalopathy that presents with neurocognitive regression and clinical seizures, and that demonstrates an electroencephalogram (EEG) pattern of electrical status epilepticus during sleep, as defined by the Commission on Classification and Terminology of the International League Against Epilepsy 1989. CSWS is an age-related condition, typically presenting in children around 5 years of age, with clinical seizures which progress within 2 years to a severe epileptic encephalopathy. The pathophysiology of CSWS is not completely understood, but the corticothalamic neuronal network involved in sleep patterns is thought to be involved. Genetic predisposition and injury in early development are thought to play etiological roles. Treatment strategies have involved traditional anticonvulsants, hormonal therapies, and other newer techniques. Outcomes are fair, and the thought is that earlier diagnosis and intervention preserve neurocognitive development, as in the case of other epileptic encephalopathies. Further understanding of the mechanisms of CSWS may lead to improved therapeutic options and thus outcomes of children with CSWS.

Working Memory and the Enactment Effect in Early Alzheimer’s Disease

This study examines the enactment effect in early Alzheimer’s disease using a novel working memory task. Free recall of action-object instruction sequences was measured in individuals with Alzheimer’s disease (n=14) and older adult controls (n=15). Instruction sequences were read out loud by the experimenter (verbal-only task) or read by the experimenter and performed by the participants (subject-performed task). In both groups and for all sequence lengths, recall was superior in the subject-performed condition than the verbal-only condition. Individuals with Alzheimer’s disease showed a deficit in free recall of recently learned instruction sequences relative to older adult controls, yet both groups show a significant benefit from performing actions themselves at encoding. The subject-performed task shows promise as a tool to improve working memory in early Alzheimer’s disease.