18F-FDG PET/CT and functional MRI in a case of crossed logopenic primary progressive aphasia. / 18F-FDG PET/TC y RM funcional en un caso de afasia progresiva primaria logopénica cruzada.

Primary progressive aphasia is a clinical syndrome caused by a neurodegeneration of areas and neural networks involved in language, usually in the left hemisphere. The term "crossed aphasia" denotes an acquired language dysfunction caused by a lesion in the hemisphere ipsilateral to the dominant hand. A case is presented on a 75-year-old right-handed woman with a logopenic variant of primary progressive aphasia with word-finding difficulties of 2 years onset. The 18F-FDG PET/CT showed right temporoparietal hypometabolism. A functional MRI scan was performed during a verb naming task in order to characterise language lateralisation patterns. A similar activation pattern was observed in both hemispheres, with less activation than expected in bilateral inferior frontal gyrus. These findings support that logopenic variant of primary progressive aphasia should not be considered as a neurodegeneration starting in the left brain hemisphere, but as a syndrome characterised by asymmetric neurodegeneration of brain regions and neural networks involved in language.

Topography of primitive reflexes in dementia: an F-18 fluorodeoxyglucose positron emission tomography study.

BACKGROUND AND PURPOSE: Although primitive reflexes (PRs) are inhibited during the first years of childhood, they may reappear with brain injury. PRs have been linked to frontal lobe dysfunction, but their precise topography has not yet been defined. The purpose of this study was to map which regions of the brain display a reduced glucose metabolism in patients with cognitive impairment and PRs. METHODS: A prospective study was conducted to evaluate PRs in a group of patients assessed due to suspected cognitive decline. Neurological and neuropsychological examinations and (18) F-fluorodeoxyglucose positron emission tomography fused with computerized tomography were performed. Voxel-based brain mapping analysis by means of statistical parametric mapping was used to compare patients with and without PRs. RESULTS: The study included 99 patients (33 diagnosed with Alzheimer's disease, 33 on the frontotemporal dementia spectrum and 33 with other diagnoses). Mean age was 71 ± 9.7 years; time since symptom onset was 3.6 ± 2.9 years. At least one PR was observed in 43 cases (43.4% of the whole sample; 48.5% in the Alzheimer disease group, 63.6% in frontotemporal dementia and 18.2% in the group with other diagnoses). The group of patients with PRs exhibited a decreased cerebral metabolism in the bilateral superior frontal gyri (Brodmann area 6), bilateral putamina and thalami. CONCLUSIONS: The presence of PRs was associated with hypometabolism at the superior frontal gyrus and putamen. This suggests that dysfunction in the corticostriatal motor circuit (supplementary motor area-putamen-thalamus) may constitute the anatomical basis of the recurrence of PRs.

Biomarkers: a new approach to behavioural variant frontotemporal dementia.

INTRODUCTION: Lobar frontotemporal degeneration (FTLD) encompasses a group of molecular disease defined by the deposition of an abnormal protein in the central nervous system. Behavioural variant frontotemporal dementia (bvFTD) is the most frequent clinical presentation of FTLD. The past two decades of research have contributed to a better understanding of this entity, which may be the first manifestation in many different neurodegenerative disorders. DEVELOPMENT: We reviewed correlations between clinical, pathological, and genetic findings and the main disease biomarkers of FTLD, with particular interest in bvFTD. Anatomical pathology findings in FTLD are heterogeneous and the syndrome is not associated with any one specific histopathological type. Promising available biomarkers include structural and functional neuroimaging techniques and biochemical and genetic biomarkers. Disease-modifying drugs designed for specific molecular targets that are implicated in FTLD pathogenesis are being developed. CONCLUSIONS: BvFTD is a frequent cause of dementia. Of all the clinical variants of FTLD, behavioural variant is the one in which establishing a correlation between clinical and pathological signs is the most problematic. A biomarker evaluation may help predict the underlying pathology; this approach, in conjunction with the development of disease-modifying drugs, offers new therapeutic possibilities.

Validation of the Spanish version of Addenbrooke's Cognitive Examination III for diagnosing dementia.

INTRODUCTION: Addenbrooke's Cognitive Examination is a screening test used to diagnose dementia. The third edition of this test (ACE-III) was recently developed. The aim of this study was to translate and validate the ACE-III in Spanish. METHODS: The ACE-III was translated and adapted to Spanish. It was then administered to a group of healthy subjects as well as a group of patients with different types of mild dementia treated in 2 hospitals in Spain. RESULTS: Internal reliability (Cronbach's alpha = 0.927), inter-rater reliability (intraclass correlation coefficient = 0.976) and test-retest reliability (kappa 0.995) were excellent. Age (r = -0.512) and education (r = 0.659) showed a significant correlation with total test scores. The diagnostic accuracy of ACE-III was higher than that of the Mini-Mental State Examination, particularly for the group with the highest educational level. Researchers obtained normative data and cut-off points for the diagnosis of dementia. CONCLUSIONS: The Spanish version of the ACE-III is a reliable and valid test for diagnosing dementia. Its diagnostic accuracy is high, especially in patients with a higher level of education.

Behavioural variant frontotemporal dementia: clinical and therapeutic approaches.

INTRODUCTION: Behavioural variant frontotemporal dementia (bvFTD) is the most frequent presentation in the clinical spectrum of frontotemporal dementia (FTD) and it is characterised by progressive changes in personality and conduct. Major breakthroughs in molecular biology and genetics made during the last two decades have lent us a better understanding of this syndrome, which may be the first manifestation in many different neurodegenerative diseases. DEVELOPMENT: We reviewed the main epidemiological, clinical, diagnostic and therapeutic aspects of bvFTD. Most cases manifest sporadically and the average age of onset is 58 years. Current criteria for bvFTD propose three levels of diagnostic certainty: possible, probable, and definite. Clinical diagnosis is based on a detailed medical history provided by family members and caregivers, in conjunction with neuropsychological testing. Treatments which have been used in bvFDT to date are all symptomatic and their effectiveness is debatable. New drugs designed for specific molecular targets that are implicated in frontotemporal lobar degeneration are being developed. CONCLUSIONS: BvFDT is a frequent cause of dementia. It is a non-specific syndrome associated with heterogeneous histopathological and biomolecular findings. The definition of clinical subtypes complemented by biomarker identification may help predict the underlying pathology. This knowledge, along with the development of drugs designed for molecular targets, will offer new treatment possibilities.

[Meralgia paraesthetica: a report on a series of 140 cases]. / Meralgia parestésica: a propósito de una serie de 140 casos.

INTRODUCTION: Meralgia paraesthetica is a pathology that is frequently seen in visits to extra-hospital neurology services. Nevertheless, the diagnosis, treatment and prognosis of this condition remain somewhat unclear. PATIENTS AND METHODS: A retrospective study was conducted involving 140 patients. Data were collected concerning demographic aspects, clinical picture, diagnostic study, aetiology, treatment and progression. RESULTS: There was a predominance of males, with a mean age of 54 years. The mean follow-up time was 25 months. The symptoms that were reported were as follows: numbness, burning pain, tingling or prickling in the nerve territory. Hypaesthesia was the most frequent sign found in the examination. History of another compressive neuropathy was present in 13.6% of patients. The diagnosis was based on the patient record and the neurological examination. The neurophysiological study and complementary tests were reserved for atypical cases. The most common causation was spontaneous and only three cases were found to be secondary to a structural lesion. A third of the patients were receiving pharmacological treatment. Although the clinical picture was benign, in most cases it tended to become chronic. Patients treated pharmacologically did not show a significant improvement in comparison to those who were not given treatment. The most important data for forecasting improvement of the clinical picture were the identification and correction of the factors precipitating compression of the nerve. CONCLUSIONS: Meralgia paraesthetica is a frequent, benign pathology but with a tendency to become chronic that responds poorly to pharmacological treatment. It is important to identify and correct mechanical factors and only in exceptional cases is it secondary to a structural lesion.

[Post-traumatic supraorbital neuralgia: a benign condition]. / Neuralgia supraorbitaria postraumática: una entidad benigna.

INTRODUCTION: Supraorbital neuralgia has only recently been described. Most of the cases reported involve patients suffering from chronic idiopathic neuralgias that are difficult to treat and sometimes require surgery to release the nerve. We present our experience in patients with a variant of this neuralgia which has a known causation, is commonly seen and has a benign prognosis. CASE REPORTS: We studied five patients, four females and one male, with a mean age of 55 years (range: 29-69 years). They had all suffered direct banal traumatic injury to the frontal region due to different causes. Four of them developed continuous, piercing or burning-type pain; three of them had paroxysmal pain and one had itching. There were no autonomic manifestations. All of them were found to be abnormally sensitive in the affected area, with tactile hypaesthesia, hyperalgesia or allodynia and a positive Tinel's sign. Neuroimaging tests were normal. Two patients were treated with gabapentin and amitriptyline. One was treated with an anaesthetic blockade, which afforded temporary relief. Three of them received no treatment at all. After one year of follow-up, all of them had improved and three were no longer in pain, although sensory alterations persisted in all cases. CONCLUSIONS: Post-traumatic supraorbital neuralgia is a frequent condition, although it is probably underdiagnosed. It has its own characteristic clinical and developmental features that distinguish it from idiopathic supraorbital neuralgia. Progress is usually good and it responds favourably to symptomatic treatment, if needed.

[Brachial presentation of spinal pseudochoreoathetosis. The result of proprioceptive information being processed in parallel]. / Seudocoreoatetosis espinal de presentación braquial. Resultado del procesamiento paralelo de la información propioceptiva.

INTRODUCTION: The term pseudochoreoathetosis is used to refer to the choreoathetoid movements that are produced by alterations in the proprioceptive sensitivity due to damage it has suffered at some point along its course. Proprioceptive sensitivity is considered to go up as far as the cortex along the posterior cords of the spinal cord, which means that if they are injured in the cervical region there should be a sensory deficit in both the upper (UL) and lower limbs (LL). CASE REPORTS: We describe five cases of transverse myelitis with localised cervical injury that selectively and mainly affected the posterior cords of the spinal cord. In the five patients there was selective involvement of the proprioceptive sensitivity in the UL respecting the LL and pseudochoreoathetoid movements of the limb that has been deafferented for proprioceptive sensitivity. The dissociation between the UL and the LL occurs because the spinocerebellar and spinocervical tracts take the proprioceptive information from the LL in parallel to the posterior cords, which receive the proprioceptive sensitivity from the UL. CONCLUSIONS: At present, the most widely accepted physiopathological mechanism explaining pseudochoreoathetosis consists in a failure in the integration of the sensory-motor afferences in the striatum, which causes faulty sensory-motor integration at this level and gives rise to pseudochoreoathetosis.