Search PubMed⌕ Search

Biomedical subjects

J Ghika

Publications and source records attributed to J Ghika.

At least 19 recordsLinked to original sources
PubMed2006

Intentional motor phantom limb syndrome.

OBJECTIVE: To investigate the clinical and anatomic correlates of a previously unreported form of chronic supernumerary phantom limb, which developed only in association with motor intent directed at a hemiplegic-anesthetic upper limb. METHODS: We explored the phenomenology of the phantom illusion in the light of motor control models. Hemodynamic correlates of supernumerary phantom limb were studied with an fMRI sensorimotor paradigm consisting of finger-thumb opposition movements. RESULTS: The kinesthetic-proprioceptive illusion of a third arm was triggered by any attempt to move the paretic limb, by bimanual actions, and by motor imagery involving the nonfunctional limb. The responsible lesion destroyed the posterior part of the posterior limb of the internal capsule on the opposite side, damaging corticospinal and thalamocortical tracts. Comparison between fMRI signals performed during virtual movement of the phantom hand vs imaginary movement of the paretic hand showed increased activation in thalamus and caudate nucleus in the first condition. CONCLUSIONS: A preserved sense of agency provided by intact premotor processes translating intention into action may lead to the vivid feeling of movement in a paralyzed limb, similar to kinesthetic illusions in amputees. The interruption of thalamic afferences may explain the persistence and stability of the phantom by preventing any correction of the mismatch between expected and effective movement. The increased blood oxygen level-dependent (BOLD) signal in the basal ganglia-thalamus-cortex pathway during movement of the supernumerary hand may reflect an abnormal closed-loop functioning of the thalamocortical system underlying the phantom phenomenon.

Aged↗
PubMed2006

Continuous assessment of electrical epileptic activity in acute stroke.

OBJECTIVE: To determine the incidence and risk factors of electrical seizures and other electrical epileptic activity using continuous EEG (cEEG) in patients with acute stroke. METHODS: One hundred consecutive patients with acute stroke admitted to our stroke unit underwent cEEG using 10 electrodes. In addition to electrical seizures, repetitive focal sharp waves (RSHWs), repetitive focal spikes (RSPs), and periodic lateralized epileptic discharges (PLEDs) were recorded. RESULTS: In the 100 patients, cEEG was recorded for a mean duration of 17 hours 34 minutes (range 1 hour 12 minutes to 37 hours 10 minutes). Epileptic activity occurred in 17 patients and consisted of RSHWs in seven, RSPs in seven, and PLEDs in three. Electrical seizures occurred in two patients. On univariate Cox regression analysis, predictors for electrical epileptic activity were stroke severity (high score on the National Institutes of Health Stroke Scale) (hazard ratio [HR] 1.12; p = 0.002), cortical involvement (HR 5.71; p = 0.021), and thrombolysis (HR 3.27; p = 0.040). Age, sex, stroke type, use of EEG-modifying medication, and cardiovascular risk factors were not predictors of electrical epileptic activity. On multivariate analysis, stroke severity was the only independent predictor (HR 1.09; p = 0.016). CONCLUSION: In patients with acute stroke, electrical epileptic activity occurs more frequently than previously suspected.

Adult↗
PubMed2006

Acute autonomic dysfunction contralateral to acute strokes: a prospective study of 100 consecutive cases.

Complex painful reflex syndrome is sometimes described in the chronic phase of stroke. Acute autonomic dysfunction (AAD), which is occasionally present in cases of acute stroke, has not been studied prospectively. The aim of the study was to investigate AAD on the hemibody contralateral to the lesion in the acute phase of stroke. One hundred consecutive patients (median age +/- interquartile range, 74 +/- 21; range 19-93; 51 women: 80 +/- 17 and 49 men: 70 +/- 17 years) in the acute phase of stroke were studied prospectively. Changes in skin temperature or coloration, diaphoresis, pain, or edema were noted in the first 3 days post-stroke. Associations between AAD and topography (cortical pre- and/or post-central, insular, corona radiata, basal ganglia, internal capsule, thalamus, and brainstem), age, gender, ischemic or hemorrhagic etiology, or the presence of sensorimotor deficits or ataxia were examined using the chi-squared or Fisher's exact test and logistic regression analysis. AAD was found in 71% of the patients and showed a significant positive association with the presence of a lesion in the post-central cortex (P = 0.037), internal capsule (P = 0.005), basal ganglia (P = 0.002), or insula (P = 0.011) and a negative association with the presence of a lesion in the brainstem (P = 0.004). Multivariate logistic regression analysis including all studied topographic variables showed that only brainstem lesions were significantly associated with a decreased risk of developing AAD (odds ratio = 0.08, 95% confidence interval: 0.01-0.69, P = 0.022). AAD was not associated with age, gender, the ischemic or hemorrhagic nature of the lesion, the side of lesion, hypertonic or hypotonic paresis, or hyperreflexia or hyporeflexia. AAD was found in association with sensory deficits (P = 0.001) and contralateral hyperkinesia (P = 0.004). Acute AAD is significantly more likely to occur in the presence of hemispheric lesions involving sensory pathways from the cortex to the internal capsule and insula and is significantly less prevalent in the presence of brainstem lesions.

Acute Disease↗
PubMed2005

[Is there a treatment for Alzheimer's disease?].

Alzheimer's disease is a frequent neurodegenerative disease, which affects more than one third of elderly persons over 80 years. No curative treatment is currently available for this disease, but symptomatic treatments have produced significant improvements in patients' condition. Cholinesterase inhibitors should be prescribed for early and moderate stages and memantine for more severe stages of the disease. These drugs have an impact on cognitive performances, may delay functional decline and improve behaviour disturbances. From a preventive perspective, evidence of benefit from early management of vascular risk factors is accumulating. In the near future, the improved comprehension of the underlying mechanisms of Alzheimer's disease will hopefully bring new treatments, thats will delay or modify its course.

Alzheimer Disease↗
PubMed2005

[Pain in Parkinson's disease].

INTRODUCTION: Pain may be a presenting symptom of Parkinson's disease or may occur during the motor fluctuation stages of the disease. The complexity and pathophysiology of pain in Parkinson's disease still remains poorly understood. OBJECTIVE: To characterize clinically the different painful presentations of Parkinson's disease, their relationship to the stage of the disease and their connections with motor fluctuations and treatment. METHODS: We reviewed painful syndromes in 388 consecutive parkinsonian patients of the Lausanne Movement Disorders Registry, based on an itemized questionnaire used prospectively to characterize the pain by its description, topography, date of appearance and possible relationship with motor fluctuations. Among these patients with clinically-diagnosed dopa-responsive Parkinson's disease, 269, i.e. 67 percent presented sensory or painful syndromes. Among them, 94 percent had muscular pain: stiffness (85 percent), cramps, pseudo-cramps, spasms (3 percent) or various myalgias (7 percent); 51 percent presented osteo-ligamentar "rheumatologic" pain, articular (23 percent), periarticular (3 percent) or spinal (31 percent), but less defined and localized neurogenic painful syndromes were less frequent (8 percent), such as paresthesia (6 percent), dysesthesia (<1 percent), burning sensation (2 percent), itching (<1 percent), ill defined discomfort (6 percent) or a feeling of heaviness (1 percent), with segmental (86 percent), axial (54 percent), radicular or pseudo-radicular (14 percent), acral distal (4 percent) or less frequently anorectal or visceral distribution. Restless legs or akathisia were occasional (10 percent). Headaches and facial pain were less frequent (1 percent), we did not encounter phantom pain. More than one quarter were present at the beginning of the disease, only (3 percent) of them resolved during the development of the disease. About one-third were clearly linked with motor fluctuations, the majority occurring in off phase (34 percent). We did not find any correlation with age, gender, duration or stage of disease, L dopa equivalent dose, depression, insomnia or autonomic dysfunction. CONCLUSION: Painful syndromes are found in two thirds of patients with Parkinson's disease, with mainly pain of muscular origin, followed by osteoarticular and neurogenic painful syndromes, a quarter of the patients experience pain in early phases of the disease and a third in relation with motor fluctuations.

Adult↗
PubMed2004

Suicide after successful deep brain stimulation for movement disorders.

The authors observed a high rate of suicide (6/140 patients, 4.3%) in a large cohort of patients with movement disorders treated with deep brain stimulation (DBS). Apparent risk factors included a previous history of severe depression and multiple successive DBS surgeries, whereas there was no relationship with the underlying condition, DBS target, electrical parameters, or modifications of treatment. Paradoxically, all patients experienced an excellent motor outcome following the procedure. The authors propose that patients at high risk for suicide should be excluded from DBS surgery.

Adult↗
PubMed2004

Subthalamic nucleus deep brain stimulation in Parkinson disease patients over age 70 years.

The effects of subthalamic nucleus deep brain stimulation were studied in 52 consecutive patients (13 over age 70, 15 under age 60, 24 age 60 to 70). All groups had improvement of motor fluctuations and dyskinesia. Patients over age 70 had worsening of Unified Parkinson's Disease Rating Scale motor scores on medication, despite less medication reduction. Their activities of daily living and axial subscores worsened, particularly in those with preoperative gait difficulties.

Age Factors↗
PubMed2004

L-dopa-induced dyskinesia improvement after STN-DBS depends upon medication reduction.

The authors studied the long-term evolution of levodopa-induced dyskinesia (LID) after levodopa challenge in two groups of six STN-deep brain stimulation-treated Parkinson disease (PD) patients, one requiring medication after surgery and the other not. A dramatic (96%) reduction of LID severity was obtained in the six postoperatively untreated patients compared to a moderate improvement (47%) in the treated group (p < 0.03). These data support dopaminergic stimulation and striatal desensitization as major determinants of LID in PD.

Aged↗
PubMed2003

Magnetic resonance artifact induced by the electrode Activa 3389: an in vitro and in vivo study.

BACKGROUND: The electrode Activa 3389 is widely implanted for deep brain stimulation (DBS) and MRI is often used to control the position of the electrode. However, induced distorsion artifacts may result in imprecise localization and may lead to misinterpretations of the clinical effects and mechanisms of DBS. METHODS: In vitro 3D MR study: the proximal and distal contacts of one electrode were spotted by two localizers. The maximal artifact height (MAH) and width (MAW: measured on distal contact), and the distances between the artifact and the localizers (proximal, distal and lateral) were measured on 2 transverse and sagittal MR sequences with 90 degrees rotation of frequency-encoded gradient and phase direction. In vivo 3D MR study: coronal and sagittal reconstructions along the main axis of the electrode were performed on 10 postoperative MR (20 electrodes) to measure MAH and MAW. A Student t test was used to compare in vitro and in vivo measurements. FINDINGS: In vitro study: A MAH of 10.35 mm (+/-0.23) and MAW of 3.6 mm (+/-0.2) were found. We measured symmetrical extensions of the artifact over the distal contact. In vivo study: A MAH of 10.36 mm (+/-0.44) and MAW of 3.56 mm (+/-0.30) were obtained. No significant different artifact dimensions were measured between in vitro and in vivo studies (p<0.0001). INTERPRETATION: Precise 3D localization of the electrode in implanted patients is provided by MR identification of the limits of the distal contact artifact. The position of the other contacts is deduced given the size of the contacts and the intercontact distance.

Artifacts↗
PubMed2003

How do parkinsonian signs return after discontinuation of subthalamic DBS?

OBJECTIVE: To study the reappearance of the clinical signs of PD when subthalamic nucleus (STN) deep brain stimulation (DBS) was turned off. METHOD: The authors studied 35 patients treated with STN DBS 6.7 +/- 3.3 months (mean +/- SD) after implantation. All were clinically improved. Twenty-four had not required any antiparkinsonian medication for many months and 11 were in "practically defined off" conditions when studied. Unified Parkinson's Disease Rating Scale (UPDRS) motor scores were assessed at baseline and 5, 15, 30, 60, 90, 120, 150, 180, and 240 minutes after switching off STN DBS. RESULTS: A sequential pattern of return of parkinsonian signs was observed, with a fast worsening of tremor within minutes, followed by a smoother, slower worsening of bradykinesia and rigidity over half an hour to an hour, and finally a slow and steady worsening of axial signs over 3 to 4 hours. Ninety percent of the UPDRS motor score worsening was reached after 2 hours. When switching STN DBS "on" again, all motor UPDRS subscores improved with a similar pattern, but faster than their rate of worsening, especially for axial signs. CONCLUSIONS: STN DBS may act by different mechanisms on the four major parkinsonian signs. At least 3 hours off STN DBS is needed to estimate the clinical effect of stimulation.

Disease Progression↗
PubMed2002

Strokes restricted to the insular cortex.

OBJECTIVE: To characterize clinically acute insular strokes from four patients with a first ever acute stroke restricted to the insula on MRI. METHODS: The authors studied the clinical presentation of four patients with a first ever acute stroke restricted to the insula on MRI. RESULTS: The authors found five main groups of clinical presentations: 1) somatosensory deficits in three patients with posterior insular stroke (two with a transient pseudothalamic sensory syndrome, one with partial distribution); 2) gustatory disorder in a patient with left posterior insular infarct; 3) vestibular-like syndrome, with dizziness, gait instability, and tendency to fall, but no nystagmus, in three patients with posterior insular strokes; 4) cardiovascular disturbances, consisting of hypertensive episodes in a patient with a right posterior insular infarct; and 5) neuropsychological disorders, including aphasia (left posterior insula), dysarthria, and transient somatoparaphrenia (right posterior insula). CONCLUSION: Strokes restricted to the posterior insula may present with pseudothalamic sensory and vestibular-like syndromes as prominent clinical manifestations, but also dysarthria and aphasia (in left lesions), somatoparaphrenia (right lesions) and gustatory dysfunction and blood pressure with hypertensive episodes in right lesions; we did not find acute dysphagia reported in anterior, insular strokes.

Aged↗
PubMed2002

Effect on mood of subthalamic DBS for Parkinson's disease: a consecutive series of 24 patients.

A series of 24 consecutive PD patients were prospectively studied prior to and within 6 months postoperatively for mood, motor, and cognitive status to investigate the effects on mood of subthalamic deep brain stimulation (DBS) in PD. In six patients (25%), mood state worsened significantly, and three were transiently suicidal despite clear motor improvement. Caregivers and patients should be educated about the potential impact of this neurosurgical procedure on mood.

Adult↗
PubMed2002

Neuropathology of a case of dopa-responsive dystonia associated with a new genetic locus, DYT14.

Detailed autopsy findings are reported for a patient with dopa-responsive dystonia genetically related to the dopa-responsive dystonia locus DYT14 on chromosome 14q13. Substantia nigra and locus ceruleus showed a normal abundance of severely hypomelanized dopaminergic neurons and no Lewy body. In the nigra, the reduction of melanin pigment was found to be asymmetric between the two sides and uneven within neurons, and the lateral aspect of the nigra appeared more affected than the medial, in a pattern similar to the neuronal loss in PD. Dopa-responsive dystonia has a unique neuropathologic signature that seems to be independent of its genotype.

Aged↗
PubMed2002

Subthalamic DBS replaces levodopa in Parkinson's disease: two-year follow-up.

BACKGROUND: Subthalamic nucleus (STN) deep brain stimulation (DBS) of patients with PD allows reduction of antiparkinsonian medication but has only a mild direct effect on dyskinesia. Since antiparkinsonian medication has short- and long-term effects that may prevent an estimate of the maximal possible impact of STN DBS, such medication was used at the lowest possible dosage after DBS implantation. OBJECTIVE: To study the maximal and long-term effects of STN DBS using the lowest dose of medication. METHODS: Twenty consecutive patients with PD with motor fluctuations and dyskinesia underwent bilateral implantation under stereotactic guidance, microrecording, and clinical control. All medications were stopped before implantation and reintroduced, at the lowest dosage needed, only if the postoperative motor score did not reach the baseline level. Unified PD Rating Scale (UPDRS) motor (subscale III) scores were measured at baseline and after 3, 6, 12, and 24 months. RESULTS: After 21 plus minus 8 months, the UPDRS III "off-medication" score was decreased by 45% and was similar to the preoperative UPDRS III "on" score. Overall, medication was reduced by 79%, being completely withdrawn in 10 patients. Fluctuations and dyskinesia showed an overall reduction of >90%, disappearing completely in patients without medication. These improvements were maintained for 2 years. CONCLUSIONS: These results show that STN DBS could replace levodopa and allowed all antiparkinsonian medication to be discontinued in 50% of patients with PD. Fluctuations and dyskinesia disappeared completely in these patients but persisted in those still on medication. These improvements were maintained for 2 years.

Aged↗
PubMed2002

Postanoxic generalized dystonia improved by bilateral Voa thalamic deep brain stimulation.

A patient with severe postanoxic dystonia and bilateral necrosis of the basal ganglia, who was confined to a wheelchair, underwent bilateral ventralis oralis anterior deep brain stimulation (Voa-DBS) after 6 weeks of unsuccessful bilateral pallidal DBS (GPi-DBS). After 4 months of high intensity Voa-DBS, cognitively unimpaired, he showed major improvement in dystonia, became ambulant, but committed suicide. Brain examination confirmed the correct location of the electrodes in GPi and Voa on both sides.

Adult↗