Clinical Neuroscience

[Investigation of cerebral autoregulation in Parkinson’s disease]


JULY 10, 2005

Clinical Neuroscience - 2005;58(07-08)

[Background and purpose - The frequent orthostatic intolerance in Parkinson’s disease could be the consequence of cardiovascular autonomic failure and/or a damaged cerebral autoregulation (AR). To clarify this question the regulation of cerebral circulation was investigated by polygraphic method. Methods - On a tilt table simultaneous and continuous registrations were made of MCA velocity (VMCA) by transcranial Doppler, arterial blood pressure by non-invasive method, and end-tidal CO2, in supine and in tilted positions of 10°, 30°, 70° grades. The cerebral autoregulation was characterized by the slope of the curve of the arterial blood pressure at the level of the Willis-circle (BPW, as MCA perfusion pressure) plotted against the MCA velocity, achieved by linear regression (y=ax+b function, a=AR, or index of autoregulation). Patients - The data of 17 parkinsonian patients (PP) and eight age-matched controls (C) were analyzed. Results - The decrease of blood pressure in parkinsonian patients was significantly lower than in the controls when supine position was restored from 70° (ΔABP 70°-0°PP= -3.1±7.5 Hgmm; ΔABP 70°-0C°=-11.1±7.3 Hgmm; p<0.05), which suggests a damage to the sympathetic cardiovascular system. A disturbance of the cerebral autoregulation in patients was suggested by a progressively decreasing MCA average velocity (VMCA) during graded tilt, which was significiant at 70° (ΔVACM=9.8±8.82% cms-1; pCPP <0,05), and by a higher slope of pressure-velocity curve (ARC=0.143±0.125% cms-1/Hgmm; ARPP=0.38±0.25% cms-1/Hgmm; pC-PP<0.05). Conclusions - The results show that the cerebral blood flow of patients is more dependent on perfusion pressure compared to healthy controls. The disturbance of the sympathetic cardiovascular system and of cerebral autoregulation could be the consequence of a damage to the postganglionic structures in Parkinson’s disease. These results could explain the frequent orthostatic intolerance of patients even with normal blood pressure.]



Further articles in this publication

Clinical Neuroscience

[Frontotemporal dementia - Part II Differential diagnosis, genetics, molecular pathomechanism and pathology]

GALARIOTIS Vasilis, BÓDI Nikoletta, JANKA Zoltán, KÁLMÁN János

[This is a comprehensive paper in three parts covering history, prevalence, clinical forms, differential diagnosis, genetics, molecular pathomechanism, pathology, clinical diagnosis and treatment of frontotemporal dementia (FTD). The second part focuses on the differential diagnosis, genetics, molecular pathomechanism and pathology. The clinical diagnosis of frontotemporal dementia is based on the presence of a prominent disturbance of the executive function and of frontal lobe syndrome or a progressive aphasic syndrome without severe global cognitive impairment. Of other dementias, it is primarily Alzheimer’s disease that it should be differentiated from, but other psychiatric disorders must also be ruled out. The disease has familial and sporadic forms. Recent identification of mutations in the gene encoding the microtubule-associated tau protein in the inherited frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17) has demonstrated that various tau dysfunctions can lead to neurodegeneration. Tau gene mutations have varied effects on the biology and function of the protein. This heterogeneous pathomechanism explains the wide range of clinical and neuropathological features observed in the FTDP-17. Tau and ubiquitin antibodies can be detected by sensitive immunohistochemical methods. The diagnosis of FTD should be based on neuropathological examination, and this is also the only method by which it can be definitely differentiated from other types of dementias.]

Clinical Neuroscience



[Introduction - While it is several decades ago that electrophysiological studies in the early stages after an ischaemic stroke revealed spontaneous activity in the affected muscles, today few data are available on the peripheral changes in later stages after a cerebrovascular event. The aim of this study was to detect electrophysiological signs that could indicate changes at the motor unit level occurring within a longer post-stroke period. Patients and methods - Forty-four patients who had developed hemiparesis after an ischaemic stroke in the area of the middle cerebral artery were involved in the study. Motor and sensory nerve conduction studies and electromyography were carried out on each side on six nerves and in five muscles respectively. Values between the affected and unaffected side were compared by statistical methods. Results - In patients with hemiparesis present for less then nine months, low M wave amplitudes, fibrillation potentials and an increased number of complex motor unit potentials were found on the affected side; in patients with symptoms present for more then nine months the mean duration and size index of the motor unit potentials in the paretic abductor digiti minimi muscle were increased. These data suggest a process of neurogenic type. The signs of distal axonal damage observed in the early period after stroke have been replaced later by chronic neurogenic changes. These changes could be the consequence of spinal motor neuron damage and axonal transport disturbance due to the loss of supraspinal trophic inputs. Conclusion - The correlation between the extent of electrophysiological changes and of the central motor deficit of the patient indicates the importance of delaying this process by appropriate rehabilitation procedures.]

Clinical Neuroscience

[Increasing cerebral perfusion pressure in serious cranial injury - contradictory effects of dopamine]

BARZÓ Pál, CZIGNER Andrea, ANTHONY Marmarou, ANDREW Beaumont, DEÁK Gábor, PANOS Fatouros, FRANK Corwin

[Background - Management of cerebral perfusion pressure is an important element of the treatment of traumatic brain injury. Vasopressors are accepted as a method of choice to increase mean arterial blood pressure and thus cerebral perfusion pressure in the face of rising intracranial pressure. There are, however, some unresolved issues and potential risks to this therapy. Matherial and methods - This study therefore examines the effects of dopamine on physiological changes as well as on brain edema and water content that can be readily assessed by MRI/MRS in 1. a rodent model of rapidly rising intracranial pressure, caused by diffuse injury with secondary insult and 2. a model of cortical contusion. Results - Dopamine was capable of restoring cerebral perfusion pressure in the model of rapidly rising intracranial pressure. However, this was associated with only a partial restoration of cerebral blood flow. In the brain tissue two profiles of change in the apparent diffusion coefficient of water (ADCw) were seen; one in which ADCw recovered to baseline, and one in which ADCw remained persistently low. Despite that dopamine did not alter these profiles, MRI-assessed tissue water content was increased four hours after injury and dopamine increased cerebral water content in both subgroups of injury, especially in the subgroup with a persistently low ADCw (p<0,01). In the contusion group dopamine significantly worsened the edema both in the injured and in the contralateral area of hippocampus and temporal cortex even though the ADCw values did not change, except for the contralateral hippocampus, where both water content and ADCw values rose with treatment, suggesting extracellular accumulation of water. Conclusion - The results suggest that dopamine has a double effect - while it temporarily and partially restores cerebral blood perfusion, at the same time it induces an increase in brain swelling and thus an increase in intracranial pressure in some cases. It is possible that in a subgroup of patients vasopressor treatment leads to an opposite effect several hours later. Vasopressor therapy in the clinical setting therefore should be cautiously applied.]

Clinical Neuroscience

[125I brachytherapy of pineal parenchymal tumours]

JULOW Jenő, VIOLA Árpád, MAJOR Tibor, VALÁLIK István, SÁGI Sarolta, MANGEL László, KOVÁCS Rita Beáta, HÁVEL János, KISS Tibor

[Introduction - Pineal parenchymal tumours make up 0,3% of all brain tumours. Stereotactic biopsy has by now become an indispensable method to detect these tumours and it can be safely performed. Patients and method - Two patients with pineoblastoma were treated with 125I brachytherapy. The MRI and CT images taken 15 and 18 months after irradiation showed significant tumour shrinkage. Results - Tumour volume was 0.76 cm3 in the control CT image in Case 1, a shrinkage by 73% compared to 2.87 cm3 measured at the time of planning the interstitial irradiation. In Case 2, tumour volume measured on the control MRI examination was 0.29 cm3 as opposed to 1.27 cm3 of original tumour volume, which represents a 77% shrinkage. Conclusion - The insertion of isotope seeds was performed at the same time as the biopsy, because thus the knowledge of the histological diagnosis could spare the patients from a second stereotactic intervention. The CT- and image fusion guided 125I stereotactical brachytherapy is a procedure that can be dosimetrically precisely planned and surgically accurately and safely performed.]

Clinical Neuroscience

[Stiff-person syndrome - two Hungarian cases and review of the literature]

LENGYEL András, LAKOS Gabriella, SIPKA Sándor, HEGEDÛS Katalin

[The stiff-man syndrome is a rare neurological disorder characterized by progressive stiffness of the axial muscles and co-contraction of agonist and antagonist muscles sometimes accompanied by involuntary sudden muscle spasms. The disease is thought to be caused by immunological changes leading to a GABA transmission disturbance, but the precise pathogenesis is not clear. Two Hungarian cases are presented in this article accompanied by a review of the literature. The aim of the paper is to call the attention on this presumably underdiagnosed disease. The diagnostic laboratory tests of the disease are available in Hungary.]

All articles in the issue

Related contents

Clinical Neuroscience

Retinal morphological changes during the two years of follow-up in Parkinson’s disease

ATUM Mahmut, DEMIRYÜREK Enes Bekir

The study aims to investigate the relationship between the progression of idiopathic Parkinson’s disease (IPD) and retinal morphology. The study was carried out with 23 patients diagnosed with early-stage IPD (phases 1 and 2 of the Hoehn and Yahr scale) and 30 age-matched healthy controls. All patients were followed up at least two years, with 6-month intervals (initial, 6th month, 12th month, 18th month, and 24th month), and detailed neurological and ophthalmic examinations were performed at each follow-up. Unified Parkinson’s Disease Rating Scale part III (UPDRS Part III) scores, Hoehn and Yahr (H&Y) scores, best-corrected visual acuity (BCVA), intraocular pressure (IOP) measurement, central macular thickness (CMT) and retinal nerve fiber layer (RNFL) thickness were analyzed at each visit. The average age of the IPD and control groups was 43.96 ± 4.88 years, 44.53 ± 0.83 years, respectively. The mean duration of the disease in the IPD group was 7.48 ± 5.10 months at the start of the study (range 0-16). There was no statistically significant difference in BCVA and IOP values between the two groups during the two-year follow-up period (p> 0.05, p> 0.05, respectively). Average and superior quadrant RNFL thicknesses were statistically different between the two groups at 24 months and there was no significant difference between other visits (p=0.025, p=0.034, p> 0.05, respectively). There was no statistically significant difference in CMT between the two groups during the follow-up period (p> 0.05). Average and superior quadrant RNFL thicknesses were significantly thinning with the progression of IPD.

Clinical Neuroscience

[The treatment of advanced Parkinson’s disease]


[The treatment of Parkinson’s disease depends on the symptoms of the patients and obviously the stage of the disease. Several different approaches can be found in the literature. Based on the published data, in this review we try to summarize the different approaches to the disease stages and theirs’ clinical relevance. Actually, one of the most important issue is the recognition of advanced stage and therefore we reviewed the device-aided therapies. ]

Clinical Neuroscience

[Earlier and more efficiently: the role of deep brain stimulation for parkinson’s disease preserving the working capabilities]

DELI Gabriella, BALÁS István, KOMOLY Sámuel, DÓCZI Tamás, JANSZKY József, ASCHERMANN Zsuzsanna, NAGY Ferenc, BOSNYÁK Edit, KOVÁCS Norbert

[Background – The recently published “EarlyStim” study demonstrated that deep brain stimulation (DBS) for the treatment of Parkinson’s disease (PD) with early fluctuations is superior to the optimal pharmacological treatment in improving the quality of life and motor symptoms, and preserving sociocultural position. Our retrospective investigation aimed to evaluate if DBS therapy was able to preserve the working capabilities of our patients. Methods – We reviewed the data of 39 young (<60 years-old) PD patients who underwent subthalamic DBS implantation at University of Pécs and had at least two years follow-up. Patients were categorized into two groups based on their working capabilities: Patients with active job (“Job+” group, n=15) and retired patients (without active job, “Job-” group, n=24). Severity of motor symptoms (UPDRS part 3), quality of life (EQ-5D) and presence of active job were evaluated one and two years after the operation. Results – As far as the severity of motor symptoms were concerned, similar (approximately 50%) improvement was achieved in both groups. However, the postoperative quality of life was significantly better in the Job+ group. Majority (12/15, 80%) of Job+ group members were able to preserve their job two years after the operation. However, only a minimal portion (1/24, 4.2%) of the Job- group members was able to return to the world of active employees (p<0.01, McNemar test). Conclusion – Although our retrospective study has several limitations, our results fit well with the conclusions of “EarlyStim” study. Both of them suggest that with optimal timing of DBS implantation we may preserve the working capabilities of our patients.]

Clinical Neuroscience

[Dopamine agonists in Parkinson’s disease therapy - 15 years of experience of the Neurological Clinics from Tîrgu Mureș. A cross-sectional study ]

SZÁSZ József Attila, CONSTANTIN Viorelia, MIHÁLY István, BIRÓ István, PÉTER Csongor, ORBÁN-KIS Károly, SZATMÁRI Szabolcs

[Background and purpose - There is relatively few data regarding the usage of dopaminagonists for the treatment of Parkinson’s disease; furthermore, there are no publications regarding Central- and Eastern-European countries. The aim of the study was to evaluate the use of dopamine agonists as a therapeutic option amongst Parkinson’s disease patients admitted to the Neurological Clinics of Tîrgu Mures during the last 15 years. Methods - In our study we investigated the data of all Parkinson’s patients treated at our clinics between the 1st of January 2003 and the 31st of December 2017. We analyzed the particularities of dopamine agonists’ usage based on the therapeutic recommendations from the final report of these patients. Regarding time since the diagnosis, we divided the patients in two groups: less than or equal to 5 years and more than 5 years. Results - During the studied period a total of 2379 patients with Parkinson’s disease were treated at the Clinics. From the 1237 patients with disease duration under 5 years 665 received dopamine agonists: 120 as monotherapy, 83 together with monoamine oxidase inhibitors and in 234 cases associated with levodopa. The remaining 228 patients were treated with a triple combination of levodopa, dopamine agonists and monoamine oxidase inhibitors. In patients suffering from Parkinson’s disease for more than 5 years, in 364 cases out of 653 a dopamine agonist was part of the therapy. Conclusion - The usage of dopamine agonists was similar to the data presented in other studies. We consider that clinicians treating the disease should, with the necessary prudence, use the available and recommended dopamine agonist with the utmost courage to their maximum therapeutic potential.]

Clinical Neuroscience

Vestibular evoked myogenic potential responses in Parkinson’s disease


Background - Our objectives were to determine the differences in the vestibular evoked myogenic potential (VEMP) responses in patients diagnosed with early staged idiopathic Parkinson’s disease (PD) compared to the normal population and evaluate the vestibular system disorder causing balance-posture disorders. Second aim of this study was to investigate caloric test responses particularly in early staged PD compared to normal popu­lation. Material and methods - Thirty patients (14 females and 16 males; mean age, 60.6 ± 13.1 years) diagnosed with idiopathic PD and 28 healthy subjects (20 males and 8 females; mean age, 59.1 ± 6.4 years) were included. The patient and control groups were subdivided according to their age, gender and the patient group was subdivided according to onset time of the Parkinson symptoms, Hoehn-Yahr staging. The subgroups were compared for VEMP and caloric test responses. Results - There were no significant differences between the study and control groups for right and left VEMP measurements. Patients over 60 years and under 60 years did not show significant differences in terms of right and left mean VEMP measurements. However, P1 amplitude was significantly lower in patients over 60 years old (P = .004). Gender, disease duration, BERG balance scale and Hoehn-Yahr stage had no effect on the VEMP amplitudes. There was no significant correlation with the side of Parkinsonian symptoms to the side of canal paresis (P = .566) and the side on which no VEMP response was obtained in caloric test. Conclusion - VEMP responses were not different between PD and healthy subjects. VEMP P1 amplitude was decreased with age in PD group. Canal paresis and symptoms side were not statistically correlated in caloric test.