Far lateral lumbar disc herniation part 1: Imaging, neurophysiology and clinical features.

Far lateral lumbar disc herniations (FLLDH) represent a separate category of disc pathology which includes both intraforaminal and extraforaminal lumbar disc herniations, that are characterized by a peculiar clinical presentation, diagnostic and treatment modalities as compared to the more frequent median and paramedian disc hernias. Surgical treatment often represents the only effective weapon for the cure of this disease and over the years different approaches have been developed that can reach the region of the foramen or external to it, with different degrees of invasiveness. The diagnosis is more demanding and still underestimated as it requires a more detailed knowledge in the spine anatomy and dedicated radiological studies. Computerized tomography and in particular magnetic resonance imaging are the appropriate tools for the diagnosis of FLLDH. Despite the widespread use of these diagnostic tests, many cases of FLLDH are overlooked due to insufficiently detailed radiological examinations or due to the execution of exams not focused to the foraminal or the extraforaminal region. Neurophysiological studies represent a valid aid in the diagnostic classification of this pathology and in some cases they can facilitate the differential diagnosis with other types of radiculopathies. In the present study, a comprehensive review of the clinical presentation, epidemiology, radiological study and the neurophysiological aspects is presented.

Botulinum neurotoxin-A does not spread to distant muscles after intragastric injection: A double-blind single-fiber electromyography study.

The purpose of this study was to perform a careful neurophysiological examination to identify subclinical signs of botulinum toxin spread distant to the injection site following intragastric injection for obesity treatment. Single-fiber electromyography of extensor digitorum communis and repetitive stimulation of abductor digiti minimi were performed before and 8 days after multiple intragastric injections of botulinum toxin A (Botox, 200 U per patient) or placebo. The study was performed in a randomized double-blind fashion. No patient in either group displayed results indicative of neuromuscular dysfunction either before or after the treatment. No significant change in muscle jitter was observed when comparing baseline with the after-treatment evaluation in either group, and no significant differences between groups were observed. After intragastric botulinum toxin injection no subclinical sign of distant spread was observed.

Overview on pathophysiology and newer approaches to treatment of peripheral neuropathies.

Peripheral neuropathies are extremely heterogeneous nosological entities. One of the most common symptoms is pain, the underlying mechanisms of which are numerous and complex. Inflammation, reparative processes, and anatomical and gene expression alterations lead to chronic pain, the persistence of which is sustained by peripheral and central sensitisation mechanisms. Treatment of peripheral neuropathies is targeted to its symptomatic and aetiological features. For pain relief, several types of drugs may be used, notably antidepressants (e.g. tricyclic antidepressants, selective serotonin reuptake inhibitors, and both serotonin and noradrenaline [norepinephrine] reuptake inhibitors), antiepileptic drugs (e.g. carbamazepine, phenytoin, lamotrigine, valproic acid, gabapentin, topiramate and pregabalin), NSAIDs and opioid analgesics. Aetiological therapy is aimed at modifying the pathophysiological mechanisms underlying the neuropathy, some of which are common in different neuropathic conditions. Certain drugs are known to exert more than one action on different pathophysiological mechanisms. This is the case with acetyl-L-carnitine (ALC), which can be considered both a symptomatic therapy that can be used in any kind of painful neuropathy, and an aetiological therapy, at least in diabetic neuropathy and neuropathies induced by nucleoside reverse transcriptase inhibitors and cancer chemotherapeutic agents. ALC acts via several mechanisms, inducing regeneration of injured nerve fibres, reducing oxidative stress, supporting DNA synthesis in mitochondria, and enhancing nerve growth factor concentrations in neurons.

Serum folate concentrations in patients with cortical and subcortical dementias.

Folic acid is believed to play a role in protection from oxidant stress. Low levels of folic acid had been found in serum from patients with Alzheimer disease (AD). Folate concentration was evaluated in sera from 136 patients with cortical dementia [AD, n=108; frontotemporal dementia (FTD), n=28], 57 patients with subcortical dementia [Lewy body disease (LBD), n=9; corticobasal degeneration (CBD), n=5; progressive supranuclear palsy (PSP), n=6; Parkinson disease with dementia (PD-Dem), n=37], and 76 nondemented, healthy age-matched people. Serum folic acid levels were decreased in patients with AD and FTD as compared with either controls or patients with subcortical dementia (3.60+/-2.22 and 5.37+/-2.92 microg/L versus 6.87+/-3.50 microg/L, respectively; P<0.01). A tendency towards decreased folate concentration was found in LBD and CBD, but not to a significant extent. The highest proportion of folate-deficient patients was found in CBD, FTD and AD (respectively, 60, 48.2 and 46.3% versus 7.9% in controls; P<0.001). Folate deficiency characterizes FTD as well as AD. These differences observed among different clinical dementing syndromes may be related to neocortical damage.

Plasma levels of beta-amyloid (1-42) in Alzheimer's disease and mild cognitive impairment.

We compared plasma levels of beta-amyloid 1-42 (pg/ml) found for 146 sporadic Alzheimer (AD) patients, 89 subjects with mild cognitive impairment (MCI) and 89 age-matched controls (CT). AD patients had significantly lower levels (38, 54, 52; p<0.01), unrelated to severity of the disease as assessed by MMSE score, age, sex or APOE4 status. Twenty cases investigated at two time points 18 months apart did not demonstrate further decreases. Thus, the reduction in beta-amyloid 1-42 may be a marker for AD status, specifically, a transition from normal status or MCI to AD, rather than a marker for neurodegenerative processes occurring in the disease.

Acute and interictal allodynia in patients with different headache forms: an Italian pilot study.

OBJECTIVE: To investigate allodynia in patients with different primary headaches. BACKGROUND: Many migraineurs have allodynia during headache attacks; some may have allodynia outside attacks; allodynia may also be associated with other primary headaches. METHODS: A total of 260 consecutive primary headache patients presenting for the first time at a headache center, and 23 nonheadache controls answered written questions (subsequently repeated verbally) to determine the presence of acute and interictal allodynia. RESULTS: We divided the patients into: episodic migraine (N = 177), subdivided into only migraine without aura (N = 114) and those sometimes or always reporting migraine with aura (N = 63); episodic tension-type headache (N = 28); chronic headaches (headache > or = 15 days/month, N = 52), including chronic migraine, chronic tension-type headache, and medication-overuse headache; and other headache forms (N = 3). Acute allodynia was present in 132 (50.7%), significantly more often in patients sometimes or always suffering migraine with aura, and those with chronic headache forms, compared to patients with migraine without aura and episodic tension-type headache. Interictal allodynia was present in 63 (24.2%) patients, with significantly higher frequency in those having migraine with aura attacks than controls and common migraine patients. CONCLUSIONS: Allodynia is not specific to migraine but is frequent in all headache patients: acute allodynia was reported in half those interviewed and in over a third of patients in each headache category; interictal allodynia was reported by nearly 25%.

Acetyl-l-carnitine in the treatment of painful antiretroviral toxic neuropathy in human immunodeficiency virus patients: an open label study.

Antiretroviral toxic neuropathy causes morbidity in human immunodeficiency virus (HIV) patients under dideoxynucleoside therapy, benefits only partially from medical therapy, and often leads to drug discontinuation. Proposed pathogeneses include a disorder of mitochondrial oxidative metabolism, eventually related to a reduction of mitochondrial DNA content, and interference with nerve growth factor activity. Carnitine is a substrate of energy production reactions in mitochondria and is involved in many anabolic reactions. Acetyl carnitine treatment promotes peripheral nerve regeneration and has neuroprotective properties and a direct analgesic role related to glutamatergic and cholinergic modulation. The aim of this study was to evaluate acetyl-l-carnitine in the treatment of painful antiretroviral toxic neuropathy in HIV patients. Twenty subjects affected by painful antiretroviral toxic neuropathy were treated with oral acetyl-l-carnitine at a dose of 2,000 mg/day for a 4-week period. Efficacy was evaluated by means of the modified Short Form McGill Pain Questionnaire with each item rated on an 11-point intensity scale at weekly intervals and by electromyography at baseline and final visit. Mean pain intensity score was significantly reduced during the study, changing from 7.35 +/- 1.98 (mean +/- SD) at baseline to 5.80 +/- 2.63 at week 4 (p = 0.0001). Electrophysiological parameters did not significantly change between baseline and week 4. In this study, acetyl-l-carnitine was effective and well tolerated in symptomatic treatment of painful neuropathy associated with antiretroviral toxicity. On the contrary, no effect was noted on neurophysiological parameters.

Alpha-dihydroergocryptine in the long-term therapy of Parkinson's disease.

The trial was designed as an open-label, post-authorisation safety study, aimed to complete the available information on adverse events and drug reactions to alpha-dihydroergocryptine (CAS 14271-05-7, alpha-DHEC). The study included 294 patients with idiopathic Parkinson's disease who received levodopa (CAS 59-92-7, L-DOPA) and started taking alpha-DHEC (Cripar). Adverse events were analysed descriptively, Parkinson's disease symptoms were documented using a questionnaire applied by the physicians. Patients were evaluated at study start and three and six months later, respectively. In 31 patients, 32 adverse events were observed, gastrointestinal and nervous system disorders being the most frequent. Dyskinesias, psychoses/hallucinations, sleep disturbances, and cardiovascular disorders were uncommon (< or = 1%). in total, 21 adverse events were classified as adverse drug reactions. In nearly 80 % of the cases, Parkinson symptoms had improved or completely vanished. Symptoms were unchanged in 16.7 % of patients and had worsened in 3.1%. The results confirm that the use of alpha-DHEC in combination therapy with levodopa in patients with Parkinson's disease is a well-tolerated and efficacious treatment option.