[Neuropsychological study of 12 patients with pure degenerative cerebellar disease]. / Evaluación cognitiva en 12 pacientes con enfermedad cerebelosa degenerativa pura.

INTRODUCTION: The cerebellum has been traditionally associated with motor control learning and performance. However, since 1970 a growing body of clinical and experimental evidences has suggested that the cerebellum may be involved in nonmotor cognitive functions as well. OBJECTIVE: To explore the presence of eventual cognitive impairment in non-demented patients with isolated degenerative cerebellar diseases. PATIENTS AND METHODS: Twelve patients with the diagnosis of selective degenerative cerebellar disorders, either inherited or sporadic, were selected (mean age: 40.42 +/- 13.49 years; mean education level: 9.92 +/- 3.99 years; duration of illness: 12.13 +/- 11.27 years, MMSE: 26.75 +/- 1.5) and evaluated through a standardized neuropsychological tests battery. Normalized Z scores were estimated and compared against 0, employing the t test for one sample. RESULTS: Significant cognitive deficits were found in the following domains: executive, visuo-spatial, memory and attention functions. Performance on the Wisconsin test showed a significative number of perseverative errors. Memory deficits included verbal learning and free recall difficulties, with good recognition of the material presented. CONCLUSIONS: The findings of this study are consistent with the role of the cerebellum as modulator of mental functions. The cognitive deficits resulting from cerebellar pathology may be related with the disruption of cerebello-cortical connexions involving a complex network which includes the prefrontal region, suggesting that the cerebellum may process cortical information coming from different areas linked with the control of cognition.

Evaluación cognitiva de 12 pacientes con enfermedad cerebelosa degenerativa pura / Neuropsychological study of 12 patients with pure degenerative cerebellar disease

Introducción. El cerebelo se ha asociado tradicionalmente con el aprendizaje y el control motor. Sin embargo, en las últimas tres décadas se ha obtenido evidencia clínica y experimental que sugiere que el cerebelo podría intervenir en el procesamiento cognitivo no motor. Objetivo. Estudiar el rendimiento neuropsicológico de pacientes con enfermedad cerebelosa degenerativa pura no dementes. Pacientes y métodos. Se evaluaron 12 pacientes con enfermedad cerebelosa degenerativa pura, de causa hereditaria o de presentación esporádica (edad: 40,42 13,49 años; educación: 9,92 3,99 años; tiempo de evolución: 12,13 11,27 años; MMSE: 26,75 1,5) por medio de una batería neuropsicológica estandarizada. Se calcularon puntuaciones normalizadas Z, que se compararon contra 0 mediante el empleo de pruebas de t de una muestra. Resultados. Se observaron alteraciones significativas en las pruebas de función ejecutiva, visuoespacial, memoria y atención. En el test de Wisconsin se registró un número significativo de errores perseverativos. Los fallos en memoria se caracterizaron por dificultades en el aprendizaje y la evocación diferida, con buen desempeño en el reconocimiento del material presentado. Los déficit cognitivos no se correlacionaron con la gravedad del déficit motor elemental. Conclusiones. Los datos obtenidos sugieren la participación del cerebelo en la modulación de las funciones mentales

Introduction. The cerebellum has been traditionally associated with motor control learning and performance. However, since 1970 a growing body of clinical and experimental evidences has suggested that the cerebellum may be involved in nonmotor cognitive functions as well. Objective. To explore the presence of eventual cognitive impairment in non-demented patients with isolated degenerative cerebellar diseases. Patients and methods. Twelve patients with the diagnosis of selective degenerative cerebellar disorders, either inherited or sporadic, were selected (mean age: 40.42 ± 13.49 years; mean education level: 9.92 ± 3.99 years; duration of illness: 12.13 ± 11.27 years, MMSE: 26.75 ± 1.5) and evaluated through a standardized neuropsychological tests battery. Normalized Z scores were estimated and compared against 0, employing the t test for one sample. Results. Significant cognitive deficits were found in the following domains: executive, visuo-spatial, memory and attention functions. Performance on the Wisconsin test showed a significative number of perseverative errors. Memory deficits included verbal learning and free recall difficulties, with good recognition of the material presented. Conclusions. The findings of this study are consistent with the role of the cerebellum as modulator of mental functions. The cognitive deficits resulting from cerebellar pathology may be related with the disruption of cerebello-cortical connexions involving a complex network which includes the prefrontal region, suggesting that the cerebellum may process cortical information coming from different areas linked with the control of cognition

Undulating toe movements in brain death.

For many years, death implied immobility. Nevertheless, there are anecdotal reports of spontaneous or reflex movements (SRMs) in patients with Brain death (BD). The presence of some movements can preclude the diagnosis of BD, and consequently, the possibility of organ donation for transplantation. McNair and Meador [(1992), Mov Dord7: 345-347] described the presence of undulating toe flexion movements (UTF) in BD patients. UTF consists in a sequential brief plantar flexion of the toes. Our aim was to determine the frequency, characteristics and predisposing factors of UTF movements in a prospective multicenter cohort study of patients with BD. Patients with confirmed diagnosis of BD were assessed to evaluate the presence of UTF using a standardized protocol. All patients had a routine laboratory evaluation, CT scan of the head, and EEG. Demographic, clinical, hemodynamic and blood gas concentration factors were analyzed. amongst 107 BD patients who fulfilled the AAN requirements, 47 patients (44%) had abnormal movements. UTF was observed in 25 (23%) being the most common movement (53%). Early evaluation (OR 4.3, CI95% 1.5-11.9) was a predictor of UTF in a multivariate regression model. The somato-sensory evoked potential (SSEPs) as well as brainstem auditory evoked potentials (BAEPs) did not elicit a cortical response in studied patients with UTF. This spinal reflex is probably integrated in the L5 and S1 segments of the spinal cord. Abnormal movements are common in BD, being present in more than 40% of individuals. UTF was the most common spinal reflex. In our sample, early evaluation was a predictor of UTF. Health care professionals, especially those involved in organ procurement for transplantation, must be aware of this sign. The presence of this motor phenomenon does not preclude the diagnosis of BD.

Spontaneous and reflex movements in brain death.

Spontaneous and reflex movements may be found in patients with brain death (BD). The authors prospectively evaluated their frequency using a standardized protocol. Among 38 patients who fulfilled criteria for BD, the authors found 15 (39%) with spontaneous or reflex movements. The most common movement was finger jerks. Undulating toe flexion sign, triple flexion response, Lazarus sign, pronation-extension reflex, and facial myokymia also were seen. These movements may be more common than reported and do not preclude the diagnosis of BD.

Catalepsy after stroke.

Catalepsy denotes a tendency to maintain postures. We prospectively looked for catalepsy in 216 acute stroke patients. We found five patients with cataleptic postures. They were seen on the nonparetic side in all cases. Other movement abnormalities seen in the catatonic syndrome were absent. CT scans of the head showed ischemic infarctions in the middle cerebral artery territory in the five cases. Cataleptic postures associated with hemispheric lesions due to stroke may be a more common phenomenon than is believed, and their mechanism remains to be elucidated.

Reliability of the NINDS Myotatic Reflex Scale.

The assessment of deep tendon reflexes is useful for localization and diagnosis of neurologic disorders, but only a few studies have evaluated their reliability. We assessed the reliability of four neurologists, instructed in two different countries, in using the National Institute of Neurological Disorders and Stroke (NINDS) Myotatic Reflex Scale. To evaluate the role of training in using the scale, the neurologists randomly and blindly evaluated a total of 80 patients, 40 before and 40 after a training session. Inter- and intraobserver reliability were measured with kappa statistics. Our results showed substantial to near-perfect intraobserver reliability, and moderate-to-substantial interobserver reliability of the NINDS Myotatic Reflex Scale. The reproducibility was better for reflexes in the lower than in the upper extremities. Neither educational background nor the training session influenced the reliability of our results. The NINDS Myotatic Reflex Scale has sufficient reliability to be adopted as a universal scale.

The effect of levodopa on the habituation of the acoustic-palpebral reflex in Parkinson's disease.

The aim of the present study was to assess the habituation of the blink responses evoked by repetitive auditory stimuli in patients with Parkinson's disease in different clinical states. We studied 28 parkinsonian patients. Eighteen patients without motor fluctuations were studied off and on levodopa, on two different sessions, one week apart. The remaining 10 parkinsonians had the wearing off phenomenon and were studied while being off their medication and while ON and OFF, as determined clinically, after a single dose of levodopa. Twelve age-matched controls were also studied in a single session. Unilateral auditory 1 kHz, 105 dB stimuli were delivered at a frequency of 0.2 Hz. The number of responses (R) from the orbicularis oculi was registered. R values were significantly smaller in controls and in treated parkinsonians than in untreated patients. R was also significantly smaller when ON than at baseline and when OFF in parkinsonians with the wearing off phenomenon. These results suggest a failure of the inhibition of the acoustic-palpebral reflex in Parkinson's disease. The improvement with levodopa and the similarities between the clinical and the electrophysiological changes suggest a dopaminergic role in the inhibition of this brainstem reflex.

Estado clínico al despertar en la enfermedad de Parkinson y su relación con el sueño / Motor function in the morning in Parkinson's disease and its relationship with sleep

Se estudiaron 36 pacientes con enfermedad de Parkinson (EP), con el fin de evaluar el probable efecto beneficioso del sueño sobre el estado motor al despertar, referido por algunos enfermos. Todos los pacientes respondieron a un cuestionario con información acerca de características de la enfermedad, presencia de fluctuaciones, medicación y trastornos del sueño. También se evaluó a los pacientes con las escalas URSPD, H&Y y de depresión geriátrica. Trece pacientes (36,1 por ciento) se sintieron mejor por la mañana, 13 peor y 10 (28 por ciento) igual. Los pacientes que se hallaban igual por la mañana tenía estadios más temprano de la enfermedad. Las fluctuaciones motoras fueron más frecuentes en el grupo que estaba peor por la mañana, los cuales tenían además menor edad. Los pacientes que estaban mejor por la mañana tendieron a tener más horas de sueño. Los trastornos del sueño en la EP no fueron distintos a los de una población control de la misma edad. Creemos que el estado motor matinal en la EP es una manifestación de las fluctuaciones motoras, aunque el número de horas de sueño también tiene una influencia positiva

Estado clínico al despertar en la enfermedad de Parkinson y su relación con el sueño / Motor function in the morning in Parkinsons disease and its relationship with sleep

Se estudiaron 36 pacientes con enfermedad de Parkinson (EP), con el fin de evaluar el probable efecto beneficioso del sueño sobre el estado motor al despertar, referido por algunos enfermos. Todos los pacientes respondieron a un cuestionario con información acerca de características de la enfermedad, presencia de fluctuaciones, medicación y trastornos del sueño. También se evaluó a los pacientes con las escalas URSPD, H&Y y de depresión geriátrica. Trece pacientes (36,1 por ciento) se sintieron mejor por la mañana, 13 peor y 10 (28 por ciento) igual. Los pacientes que se hallaban igual por la mañana tenía estadios más temprano de la enfermedad. Las fluctuaciones motoras fueron más frecuentes en el grupo que estaba peor por la mañana, los cuales tenían además menor edad. Los pacientes que estaban mejor por la mañana tendieron a tener más horas de sueño. Los trastornos del sueño en la EP no fueron distintos a los de una población control de la misma edad. Creemos que el estado motor matinal en la EP es una manifestación de las fluctuaciones motoras, aunque el número de horas de sueño también tiene una influencia positiva (AU)

[Hemichorea associated with cerebral toxoplasmosis and AIDS]. / Hemicorea asociada a toxoplasmosis cerebral y SIDA.

Only 12 AIDS cases with hemichorea were reported in the literature. We report the first case of hemichorea associated with AIDS and cerebral toxoplasmosis in our country. A 26-year-old man had 3 episodes of focal seizures on the left side with subsequent loss of consciousness. A few weeks later, he noticed progressive left-sided weakness. Examination revealed a left hemiparesis. MRI of the head showed a round mass in the right frontal lobe and a smaller lesion in the left temporo-occipital area. Laboratory showed positive serum ELISA and Western Blot analysis for HIV antibodies. Serum tests for Toxoplasma showed elevated titers. He was treated with pyrimethamine and sulfadiazine. His weakness improved and he had no further seizures. Two weeks later, choreic movements appeared in the left foot, finally involving the entire left hemibody. A second MRI showed a new small lesion in the right cerebral peduncle. The patient completed 6 weeks of treatment, with further reduction in the size of the lesions. Nevertheless, the left hemichorea persisted. We believe that the hemichorea our patient had was caused by the contralateral peduncular lesion. Lesions involving the subthalamic nucleus or its connections may cause contralateral hemiballismus or hemichorea. In spite of the favorable response to antitoxoplasmic therapy, the hemichorea persisted. The present report illustrates an uncommon neurological complication in AIDS. We believe that a combination of a focal cerebral lesion and the HIV infection caused the movement disorder presented by the patient.

Hemicorea asociada a toxoplasmosis cerebral y SIDA / Hemichorea associated with cerebral toxoplasmosis and AIDS

Se observan complicaciones neurologicas en 40 por ciento de enfermos con SIDA. De estos, en 10 por ciento puede ser la manifestación inicial de la enfermedad. En otro 11 por ciento pueden aparecer trastornos del movimimiento. Comunicamos el primer caso de hemicorea asociada a toxoplasmose cerebral y SIDA en nuestro pais. Hombre de 26 anos, con diagnóstico de SIDA y toxoplasmosis cerebral. Habia comenzado con crisis motoras simples de hemicuerpo izquierdo, con generalización secundaria y luego perdida de fuerza progresiva en dicho hemicuerpo. La RMN de cerebro mostro una lesión frontal derecha y otra temporo-occiptal izquierda, con gran edema perilesional y efecto de masa. Las serologias para HIV y toxoplasmosis fueron positivas. Comenzo tratamiento con sulfadiazina y pirimetamina. Al duodecimo dia aparecieron movimientos involuntários del pie izquierdo, coreicos, que se extendieron mas tarde a todo ese miembro inferior y luego al hemicuerpo. Nueva RMN de cerebro mostro disminución del edema y efecto de masa de las lesiones. Sin embargo, se observó una nueva lesion a nivel peduncular derecho. Movimientos involuntarios en pacientes con toxoplasmosis cerebral la literatura mundial y el primero en nuestro pais de hemicorea asoicada a toxplasmosis y SIDA

Motor activation time in Parkinson's disease.

Motor activation time (MAT), considered in the present work as the actual intracerebral processing delay during a reaction time (RT) task, was assessed in 17 patients with Parkinson's disease (PD) and in 7 age-matched healthy volunteers. MAT was calculated by subtracting from the premotor RT the afferent and efferent times obtained by sensory and motor evoked potentials. When compared with healthy volunteers, patients exhibited significantly (p < 0.02) prolonged MATs. In a smaller group of 9 PD patients MAT and the auditory P3 event related potential were assessed while on antiparkinsonian treatment and after a 12-hour withdrawal period. During the off medication condition patients showed a significant slowing (p < 0.01) of MAT values without any remarkable change in P3 latency or amplitude. These results suggest that MAT slowing indicates an abnormal function of the dopaminergic mechanism involved in the initiation of movement which is not related to changes in the arousal or cognitive state.

Motor activation time in Parkinsons disease.

Motor activation time (MAT), considered in the present work as the actual intracerebral processing delay during a reaction time (RT) task, was assessed in 17 patients with Parkinsons disease (PD) and in 7 age-matched healthy volunteers. MAT was calculated by subtracting from the premotor RT the afferent and efferent times obtained by sensory and motor evoked potentials. When compared with healthy volunteers, patients exhibited significantly (p < 0.02) prolonged MATs. In a smaller group of 9 PD patients MAT and the auditory P3 event related potential were assessed while on antiparkinsonian treatment and after a 12-hour withdrawal period. During the off medication condition patients showed a significant slowing (p < 0.01) of MAT values without any remarkable change in P3 latency or amplitude. These results suggest that MAT slowing indicates an abnormal function of the dopaminergic mechanism involved in the initiation of movement which is not related to changes in the arousal or cognitive state.

Peripheral nervous system and spinal cord involvement in lymphoma.

Nine-hundred-eighty-nine patients with diagnosis of lymphoma were studied. Forty-six cases (4.6%) had compressions of the spinal cord or roots. Forty-two patients (4.2%) had Herpes zoster virus infections, which in 6 cases were of disseminated type. The major predisposing factors for infection were: advanced stage of lymphoma, previous systemic chemotherapy and splenectomy. Toxic polyneuropathy secondary to chemotherapy was found in 39 patients (3.9%). In 14 cases, the polyneuropathic symptoms were the main complaint (Group 1), while in the remaining 25 cases the diagnosis was made during neurological consultations because of unrelated symptoms (Group 2). Both groups did not have significant differences in the total dose of chemotherapy received. The electrophysiological studies showed an axonal neuropathy in both groups. The discontinuation of chemotherapy was found to be a limiting factor in the appearance of neuropathic symptoms. Other less frequent forms of involvement were: compression of peripheral nerves or nerve plexi from lymphadenopathies (3 cases), radiation myelopathy (1 case), and Guillain-Barré Syndrome associated with Hodgkin's Lymphoma (1 case).

Habituación del reflejo acústico-palpebral en la enfermedad de Parkinson / Habituation of the acoustic-blink reflex in Parkinson's disease

La oclusión palpebral ante un estímulo auditivo sorpresivo es una respuesta refleja [RAP] polisináptica de integración mesencefálica que tiende a desaparecer frente a estímulos repetidos. Este reflejo transcurre a través del núcleo coclear, cuerpo trapezoide, collículo inferior y sus conexiones, y está sujeto a influencias supramesencefálicas. En el estudio presente, se evaluaron electrofisiológicamente 6 individuos normales y 6 pacientes con enfermedad de Parkinson de edades similares. Se aplicaron estímulos tonales registrándose la actividad refleja en el orbicular de los párpados. Se midieron latencia [L], duración [D], amplitud [A] y fases [F] de las respuestas reflejas obtenidas por aplicación de estímulos auditivos a intervalos randomizados, y luego de un período de reposo, se midió el número de respuestas obtenidas [R] aplicando los estímulos a una frecuencia fija de 0,2 Hz. No se observaron diferencias significativas en L,D,A y F, viéndose en cambio, un mayor número de R en los enfermos de Parkinson. Esta observación sugiere una alteración en la habituación a los estímulos auditivos posiblemente debida a fallas en la inhibición de este reflejo por compromiso de estructuras supramesencefálicas

Habituación del reflejo acústico-palpebral en la enfermedad de Parkinson / Habituation of the acoustic-blink reflex in Parkinsons disease

La oclusión palpebral ante un estímulo auditivo sorpresivo es una respuesta refleja [RAP] polisináptica de integración mesencefálica que tiende a desaparecer frente a estímulos repetidos. Este reflejo transcurre a través del núcleo coclear, cuerpo trapezoide, collículo inferior y sus conexiones, y está sujeto a influencias supramesencefálicas. En el estudio presente, se evaluaron electrofisiológicamente 6 individuos normales y 6 pacientes con enfermedad de Parkinson de edades similares. Se aplicaron estímulos tonales registrándose la actividad refleja en el orbicular de los párpados. Se midieron latencia [L], duración [D], amplitud [A] y fases [F] de las respuestas reflejas obtenidas por aplicación de estímulos auditivos a intervalos randomizados, y luego de un período de reposo, se midió el número de respuestas obtenidas [R] aplicando los estímulos a una frecuencia fija de 0,2 Hz. No se observaron diferencias significativas en L,D,A y F, viéndose en cambio, un mayor número de R en los enfermos de Parkinson. Esta observación sugiere una alteración en la habituación a los estímulos auditivos posiblemente debida a fallas en la inhibición de este reflejo por compromiso de estructuras supramesencefálicas

Craniocerebral involvement in lymphoma.

Nine-hundred-eighty-nine patients with lymphoma were studied. Fifty-three cases (5.3%) had lymphomatous craniocerebral infiltration. The principal factors of risk for this complication were: advanced stage of the lymphoma (III or IV), diffuse histiocytic, diffuse poorly differentiated lymphocytic, or mixed cellularity lymphoma histological type, bone marrow involvement, and previous systemic chemotherapy. Thirty-two per cent of the cases of meningeal lymphomatous infiltration were asymptomatic and represented autopsy findings. CT-scan was an useful test to detect brain focal parenchymatous infiltration, as opposed to meningeal infiltration. Mean survival time in patients with lymphomatous meningeal infiltration was 4.3 months, following the combined use of systemic chemotherapy, radiation therapy and intrathecal methotrexate. Two cases had primary cerebral lymphoma, although without associated immunodeficiency. Twenty patients (2%) had intracranial hemorrhage, in clear relationship with platelet alterations. Fifteen patients (1.5%) had CNS infection, caused by common bacteria or opportunistic agents. In 7 cases, the diagnosis was made at autopsy. Thirty-six autopsies were performed. In 8 cases (22%), pathologic findings such as, demyelination, microcalcifications, coagulative necrosis, or gliosis, suggested complications from treatment.

In vivo 31P NMR profiles of Alzheimer's disease and multiple subcortical infarct dementia.

We used in vivo phosphorus 31 nuclear magnetic resonance (31P NMR) spectroscopy to study regional high-energy phosphate and phospholipid metabolism in brains of patients with dementia associated with probable Alzheimer's disease (AD) and multiple subcortical cerebral infarctions (MSID). The MSID patients demonstrated elevations of the phosphocreatine (PCr)/inorganic orthophosphate (Pi) ratio in both the temporoparietal and frontal regions. Phosphomonoesters (PME) and the ratio of PME to phosphodiesters were elevated in the temporoparietal region of AD. Pi was also elevated in the frontal and temporoparietal regions of AD. Findings from 31P NMR were accurate in distinguishing MSID from AD. Values of PCr/Pi accurately classified 100% of the MSID patients and 92% of AD. Pi and PME, considered jointly, also accurately classified all MSID and all but 1 AD. Findings from in vivo 31P NMR spectroscopy appear to yield metabolic profiles useful in distinguishing AD from MSID.