Cardiovascular Alterations After Spinal Cord Injury: An Overview

The recent developments in the management of spinal cord injury (SCI) have led to a reduction in mortality and in the consequences, resulting from incomplete spinal cord damage in those who survive. In this respect, it is noteworthy that SCI not only results in paraplegia or tetraplegia, but also in systemic, cardiovascular and metabolic alterations secondary to autonomic dysfunction. After SCI there is a decrease in sympathetic discharge and an increase in parasympathetic drive, resulting in profound changes in arterial blood pressure and heart rate. When SCI is induced in experimental animals, an immediate hypotension occurs (acute phase) which has been attributed to an autonomic imbalance involving a predominance of parasympathetic activity. Subsequently, an episodic hypertension may develop (chronic phase) as a part of a condition denominated autonomic dysreflexia. This hypertension is caused by afferent stimulation below the level of injury and can be so severe that sometimes may lead to cerebral haemorrhage, seizures, and death. In the light of the above lines of evidence, experimental SCI may provide an ideal model to study the nature of cardiovascular mechanisms following traumatic injury. Thus, the present review will deal with an update of the possible cardiovascular complications associated to SCI (including spinal shock, autonomic dysreflexia, deep venous thrombosis, and risk for coronary heart disease). This will be discussed within the context of the development of drugs with potential therapeutic usefulness in the acute and chronic stages of SCI.

Pharmacological profile of the vascular responses to dopamine in the canine external carotid circulation

The present study investigated the effects of dopamine on the canine external carotid circulation. One min. intracarotid artery (i.c.) infusions of dopamine (10-310 microg min.-1) produced dose-dependent decreases in the canine external carotid conductance without affecting blood pressure or heart rate. This effect was mimicked by the D1/2-like receptor agonist apomorphine (1-310 microg min-1), but not by the D2-like receptor agonist, bromocriptine (31-310 microg min.-1). In contrast, fenoldopam (1-310 microg min.-1, intracarotid), a D1-like receptor agonist, produced dose-dependent increases in external carotid conductance. The vasoconstrictor response to dopamine was abolished after intravenous administration of the antagonists, phentolamine (alpha1/2; 2000 microg kg-1) or rauwolscine (alpha2; 100 microg kg-1), but remained unaffected after prazosin (alpha1; 100 microg kg-1) or haloperidol (D2-like; 1000 microg kg-1). Interestingly, after phentolamine not only were the vasoconstrictor responses to dopamine abolished, but even a dose-dependent vasodilator component was unmasked. These vasodilator responses to dopamine remained unchanged after intravenous haloperidol or propranolol (1000 microg kg-1 each). On the other hand, the vasodilator responses to fenoldopam, which remained unchanged after intravenous saline (0.1 ml kg-1), propranolol (1000 microg kg-1) or vagosympathectomy, were abolished by the D1-like receptor antagonist, SCH-23390 (10 microg kg-1). Lastly, the responses to dopamine and fenoldopam were not significantly altered after intraperitoneal pretreatment with reserpine (5 mg kg-1; -24 hr). The above results suggest that the canine external carotid vasoconstrictor responses to dopamine: (i) are mainly mediated by alpha2-adrenoceptors; and (ii) overshadow a vasodilator component, which involves vascular D1-like receptors.

Knowledge of the legislation governing proxy consent to treatment and research

OBJECTIVE

To assess the knowledge of four groups of individuals regarding who is legally authorised to consent to health care or research involving older patients.

DESIGN

A provincewide postal survey.

SETTING

Province of Quebec, Canada.

PARTICIPANTS

Three hundred older adults, 434 informal caregivers of cognitively impaired individuals, 98 researchers in aging and 136 members of research ethics boards (REBs).

MEASUREMENTS

Knowledge was assessed through a pretested postal questionnaire comprising five vignettes that describe hypothetical situations involving an older adult who requires medical care or is solicited for research. The respondent had to identify the person who is legally authorised to provide consent.

RESULTS

Nearly 80% of all respondents provided the correct answer when the hypothetical scenario depicted a person who was competent to consent or incompetent but legally represented. Knowledge was worse (from 2% among older adults to 44% among REB members) for the scenario describing a research situation that involved an incompetent adult without a legal guardian.

CONCLUSION

The observed lack of knowledge raises doubts about the ability of current legislation to truly protect the rights of older adults with diminished decision making capacity. It points to the need for educational programmes aimed at increasing public awareness of the legislation put in place for those requiring special protection.

Predictors of handicap situations following post-stroke rehabilitation

PURPOSE

Many stroke survivors have to cope with impairments and disabilities that may result in the occurrence of handicap situations. The purpose of the study was to explore bio-psycho-social predictors of handicap situations six months after discharge from an intensive rehabilitation programme.

METHODS

At discharge from a rehabilitation programme, participants were evaluated with instruments measuring motor, sensory, cognitive, perceptual, affective and psychosocial impairments and disabilities that may play a role in the development of handicap. Some other demographic and clinical variables, and those related to rehabilitation, were also collected. Six months later, they were re-assessed in their own environment in order to document their handicap level with the Assessment of Life Habits (LIFE-H).

RESULTS

One hundred and thirty-two stroke patients participated in the discharge evaluation and 102 of them also participated in the handicap measurement. Relationships between handicap level and impairments and disabilities were all statistically significant. Multiple regression analyses indicated that affect, lower extremity co-ordination, length of stay in rehabilitation, balance, age and comorbidity at the end of an intensive rehabilitation programme are the best predictors of handicap situations six months later (adjusted R(2): 68.1%).

CONCLUSIONS

In spite of its exploratory nature, this study revealed that, among a substantial number of personal characteristics, some were more related to a handicap measure and have greater predictive value. Other studies should be carried out to validate these findings and to consider more environmental factors in order to better understand factors related to the development of handicap situations.

Lipid peroxidation by nitric oxide supplements after spinal cord injury: effect of antioxidants in rats

To determine the extent to which exogenous nitric oxide (NO) might affect hemodynamics and/or increase oxidative damage after acute spinal cord (SC) injury, rats were submitted to SC contusion, and given a NO donor or NO precursor. Intravenous isosorbide dinitrate (10 microg/kg per min) or L-arginine (300 mg/kg per 23 h) showed a tendency to increase lipid peroxidation (LP), although without reaching significance compared to non-treated injured rats 24 h post-injury, and without affecting mean arterial pressure and heart rate importantly. LP due to injury and exogenous NO was significantly inhibited by the co-administration of a cocktail of antioxidants (12 mg/kg superoxide dismutase mimetic, 27000 U/kg catalase, and 12 mg/kg glutathione), but less effectively for the injury-L-arginine condition. These results demonstrate that in order to further test the potential neuroprotective effect of NO enhancing reagents after SC injury, antioxidants must be included in the treatment scheme.

Sympathetic blockade significantly improves cardiovascular alterations immediately after spinal cord injury in rats

Immediately after an experimental spinal cord injury (SCI) in rats, there is a large fall in mean arterial pressure (MAP) and heart rate (HR), followed by an abrupt increase in MAP. To better understand the mechanism involved in these early cardiovascular alterations, we tested the effect of treatment with ganglionic and sympathetic blockers in anesthetized rats subjected to T-5 SCI. Fall in MAP was partially diminished by propranolol and pentolinium, while increase in MAP was abolished by propranolol and pentolinium. Adrenalectomy did not diminish the fall in MAP and HR, however, the increase in MAP was significantly reduced. Likewise, propranolol and pentolinium completely abolished the effects in HR. These data suggest that the early cardiovascular alterations secondary to SCI results from an increased parasympathetic activity and a sympathetic withdrawal.

Correlates of psychotropic drug use in the elderly compared to adults aged 18-64: results from the Quebec Health Survey

This study documents correlates of psychotropic drug use among older adults and compares the results observed in this group to those observed in individuals aged 18-64. A multivariate logistic regression analysis using data from the Quebec Health Survey (1992-1993) was employed to study predisposing and facilitating factors of this behavior. Results showed that 22% of the elderly reported having used anxiolytics, sedatives or hypnotics during the two days preceding the survey, compared to 4.9% of the respondents aged 18-64. Combining both samples, perceived health status, physical functional status, and health services utilization for psychological distress symptoms were the main health factors associated with psychotropic drug use. A significant difference was observed between the two age groups with regard to the association between the respondents' health status and the use of anxiolytics, sedatives or hypnotics. When the effect of other explanatory factors was controlled, older adults in poor health used anxiolytics, sedatives or hypnotics 2.21 times more than individuals aged 18-64 with a similar health condition, whereas older adults in good health used these drugs 7.49 times more than healthy individuals aged 18-64. Furthermore, after controlling for the effect of the respondents' physical and psychological health status, our results showed that more women than men used psychotropic drugs (OR = 1.57; 99% CI = 1.26-1.94). Low-income respondents were also more likely to report using these medications (OR = 1.53; 99% CI = 1.22-1.90). These results were interpreted as supporting the socio-cultural hypothesis of psychotropic drug use, which suggests that the prescribing and utilization of psychotropic drugs is influenced not only by symptoms but also by the social characteristics of individuals. It is suggested that future research may contribute to a better understanding of psychotropic drug utilization in the older adult community-dwelling population by examining consumers' attitudes and health care providers' social values concerning the appropriateness of this behavior.

Features of the engraftment of allogeneic hematopoietic stem cells using reduced-intensity conditioning regimens

The features of the engraftment in 26 patients allografted using reduced-intensity conditioning regimen (8 with chronic myelogenous leukemia, 6 with acute myelogenous leukemia, 9 with acute lymphoblastic leukemia, 1 with hybrid acute leukemia, 1 with myelodysplasia and 1 with thalassemia major) were analyzed. Patients received a median of 10 x 10(8)/Kg mononuclear cells (range 1.6 to 22.9), and a median of 4.2 x 10(6)/Kg CD34 cells (range 0.3 to 14). There was a linear correlation between the number of infused mononuclear cells (MNC) and that of CD34 cells (r = 0.78, p = 0.002). Three patients (11%) failed to engraft; in those who engrafted, the median time to achieve > 500 granulocytes was 11 days (range 10 to 22), and the median time to achieve > 10,000 platelets was 12 days (range 10 to 41). The three patients who failed to engraft received less than 5 x 10(8)/Kg MNC (1.6, 4.6 and 4.9) and less than 0.5 x 10(6)/Kg CD34; however, five of eight patients who received less than 5 x 10(8)/Kg MNC still engrafted successfully. On the other hand, all the patients who received less than 0.5 x 10(6)/Kg CD34 cells failed to engraft. Within the group of patients who engrafted, it was found that those who received more than 7 x 10(6)/Kg CD34+ cells tended to earlier recover > 20 x 10(9)/L platelets (p = 0.02), and > 0.5 x 10(9)/L neutrophils (p = 0.06) before day 15, than those who received less than 7 x 10(6)/Kg CD34+ cells. No such association could be established between the number of MNC and the time for recovery. In these patients allografted using reduced-intensity conditioning regimens, the target doses of hematopoietic cell used were similar to those described for conventional allografts: The number of CD34 infused cells was significantly related to the possibility of failure to engraft and to the recovery rate of the hemopoiesis.

Efficacy of a nurse-led multidimensional preventive programme for older people at risk of functional decline. A randomized controlled trial

OBJECTIVE

To verify the efficacy of a multidimensional preventive programme on functional decline of older people.

DESIGN

Randomized controlled trial.

SETTING

Community of Sherbrooke City, Quebec, Canada.

SUBJECTS

A representative sample of individuals aged over 75 living at home and identified to be at risk of functional decline by postal questionnaire (n = 503).

INTERVENTION

Subjects randomized to the study group (n = 250) were assessed at home by a nurse on 12 dimensions (including medication, depressive mood, risk of falls, hearing). A report of the assessment was sent to the general practitioner with recommendations for interventions. A monthly telephone contact was carried out by the nurse for surveillance and to verify if the recommendations had been applied.

METHODS

The primary outcome--functional decline--was defined as either death, admission to an institution or increase of > or = 5 points on the disability score of the Functional Autonomy Measurement System (SMAF) scale during the reference year. Secondary outcomes were functional autonomy (on the SMAF), well-being (General Well-being Schedule), perceived social support (Social Provisions Scale) and use of health care services.

RESULTS

Of the 494 subjects who completed the study, 48 (19.6%) of 245 in the study group and 49 (19.7%) of 249 in the control group had functional decline (relative risk 1.00; 95% confidence interval 0.82-1.23). There were no differences between the groups in all secondary outcomes.

CONCLUSIONS

This study confirms the inefficacy of multidimensional programmes for preventing functional decline in the older population. More effort should be devoted to improving the efficacy of specific interventions for conditions causing functional decline.

Mechanisms involved in the cardiovascular alterations immediately after spinal cord injury

The early cardiovascular effects resulting from an acute spinal cord injury (SCI) produced by a contusion procedure at T5-T6 were evaluated in anaesthetized rats. The mean arterial pressure (MAP) and heart rate (HR) were measured during one hour after the injury. A marked decrease in MAP and HR was observed immediately after injury, followed by an abrupt increase in MAP. These changes were observed between 3 and 9 min and the basal values were recovered after 20 min. Fall in the MAP and HR and increase in MAP induced by SCI were abolished by atropine. The interruption of the parasympathetic outflow by vagotomy also significantly diminished the fall and increase in MAP and the fall in HR. Likewise, pre-treatment with nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) completely abolished the effects produced by SCI. These data suggest that after SCI the decrement in MAP and HR was probably due to acetylcholine release from parasympathetic fibers and NO from endothelial source probably by a cholinergic stimulation. Additionally, the MAP increase observed was probably due to a reflex compensatory vasoconstriction.

Further pharmacological analysis of the orphan 5-HT receptors mediating feline vasodepressor responses: close resemblance to the 5-HT7, receptor

It has been suggested that the late hypotensive response to serotonin (5-hydroxytryptamine; 5-HT) in vagosympathectomised cats, being potently mimicked by 5-carboxamidotryptamine (5-CT), not modified by ketanserin and blocked by methiothepin or methysergide, is mediated by '5-HT1-like' receptors. Nevertheless, current guidelines for 5-HT receptor classification refer to this receptor as an orphan receptor. Thus, the present study set out to reanalyse the above suggestion in terms of the classification schemes proposed in 1994 and 1998 by the NC-IUPHAR subcommittee on the classification of 5-HT receptors. Intravenous (i.v.) bolus injections of 5-CT (0.003-0.3 microg/kg), 5-HT (1-100 microg/kg) and 5-methoxytryptamine (5-MeO-T; 1-100 microg/kg) produced dose-dependent vasodepressor responses with a rank order of agonist potency of 5-CT >> 5-HT = 5-MeO-T with sumatriptan (10-300 microg/kg) virtually inactive. The vasodepressor responses to 5-HT, 5-CT and 5-MeO-T were not attenuated following i.v. administration of the antagonists GR127935 (5-HT(IB/ID); 30 microg/kg), tropisetron (5-HT3/4; 3000 microg/kg), (+/-)-pindolol (beta-adrenergic and 5-HT1A; 4000 microg/kg) or equivalent volumes of physiological saline. In contrast, the above vasodepressor responses were markedly and specifically antagonised by i.v. methiothepin (100 microg/kg), lisuride (30 microg/kg and 100 microg/kg), mesulergine (300 microg/kg and 1000 microg/kg) or LY215840 (300 microg/kg and 1000 microg/kg). The above lines of evidence, therefore, indicate that the orphan receptors mediating the vasodepressor responses to 5-HT in vagosympathectomised cats are pharmacologically similar to other 5-HT7 receptors mediating vascular and non-vascular responses (e.g. relaxation of the canine external carotid artery and guinea-pig ileum as well as feline tachycardia).

[Neural transplants en Parkinson disease: clinical results of 10 years of experience. Group of Neural Transplants of the CPH]

INTRODUCTION

At the end of the 1970s people considered the possibility that transplants might be useful to replace degenerate specific cell populations, such as the mesencephalic dopaminergic neurones in Parkinson's disease (PD). Since then this has become an experimental alternative treatment for patients with degenerative diseases. The history of transplants of catecholamine producing tissues within the brain of patients with PD started in 1985, when Backlund et al published the results of the first implants of autologous adrenal medulla in two patients with Parkinsonism. Since then, many patients throughout the world have benefited from the results obtained using this method. Two main types of tissue have been used in this method: autologous adrenal medulla and human foetal ventral mesencephalic tissue.

DEVELOPMENT

In this paper we first review the clinical effects of the diverse types of transplant done to date. Then in the second part we give a summary of the clinical results obtained by our group with the different types of transplant carried out. We explain their evolution, original hypothesis and justify the reasons which led us to use three different types of donor material: autologous adrenal medulla, fetal tissue and adrenal medulla co-incubated with peripheral nerve. Then, after showing that the clinical improvement is different depending on the type of tissue transplanted, we comment on the probable reason for the improvement seen in patients with implants.

CONCLUSION

The transplantation of nervous tissue seems to us to be no longer an experimental alternative for the treatment of PD but has become an effective, lasting treatment for patients with Parkinson's disease.

Recurrence in a different location of a cerebral arteriovenous malformation in a child after radiosurgery

The case of a 9-year-old girl with a right parietal arteriovenous malformation (AVM) of the brain obliterated after gamma knife (GK) radiosurgery with subsequent regrowth in a different site is reported. As far as we know, this is the first reported case of regrowth of an AVM in a different location after radiosurgery in a child. This situation has to be considered within the context of causes of unsuccessful treatment of AVMs with radiosurgery and justifies angiographic monitoring of pediatric patients until they reach adulthood.

Spontaneous cerebrospinal fluid fistulae associated with empty sellae: surgical treatment and long-term results

OBJECTIVE

To evaluate the accuracy of different diagnostic tools for cerebrospinal fluid fistulae (CFFs) associated with empty sellae and to assess the long-term results after surgical treatment.

METHODS

Records were retrospectively reviewed for 38 of 44 patients who were treated for CFFs associated with empty sellae between 1972 and 1996. Glucose and radioisotope analyses of nasal fluids were used to establish the CFF diagnosis. Computed tomography, magnetic resonance imaging, and cisternography were used to localize the sites of the CFFs. Treatment was performed using three different approaches, i.e., subfrontal approach, transsphenoidal approach, and lumboperitoneal shunt placement.

RESULTS

Glucose and radioisotope analyses of nasal fluids confirmed CFFs in 97 and 100% of the cases, respectively. For localization of the sites, a leak in the sella was suggested in 32% of the cases using gammagraphy, in 50% using computed tomography or magnetic resonance imaging, and in 75% using computed tomographic contrast cisternography. After surgery, rhinorrhea ceased for 34 patients (89%), but 14 (41%) patients experienced recurrences of the rhinorrhea 6 months to 20 years after surgery (mean, 4.2 yr). Cure rates for the subfrontal approach, transsphenoidal approach, and shunt placement were 94, 85, and 86%, and the recurrence rates were 43, 33, and 50%, with mean times of 7.8, 4.2, and 0.8 years, respectively.

CONCLUSION

In this series, confirmation of CFFs was easy, although localization of the sites remained difficult. Recurrences were more numerous and occurred sooner after treatment with shunts; packing of the sella through a craniotomy achieved better and more stable results, although differences were not statistically significant.

Early changes in nitric oxide synthase activity in atrial intramural arteries following experimental spinal cord injury in rats

Previously, we have shown that immediately after an experimental spinal cord injury (SCI) in anaesthetized rats, there is a large fall in mean arterial pressure (MAP) and heart rate (HR), followed by an abrupt increase in MAP. To evaluate the participation of nitric oxide (NO), we evaluated the activity of nitric oxide synthase (NOS) using Nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase histochemistry in sections of atria at several post-injury time-intervals. Staining increased at 3 min, reached a maximum at 9 min and diminished 30 min after injury. Pretreatment with atropine prevented changes in MAP, HR and NADPH-d staining suggesting that such modifications result from an increased vagal stimulation. In conclusion, the NOS activity is transiently elevated in the atrial intramural arteries of rats subjected to an SCI.

Age-related changes in upper extremity performance of elderly people: a longitudinal study

The objective of this research was to study age-related changes in the upper extremity performance of healthy community-dwelling elderly people, by using a longitudinal design. In 1995-1996. gross and fine manual dexterity, global performance, motor coordination, grip strength, tactile recognition, two-point discrimination, touch/pressure threshold, and tactile localization of 264 of the 360 subjects initially evaluated in 1992-1993 were reevaluated by using the same upper extremity measuring instruments. Those who did not participate (n = 96) were found to be significantly different from those who participated in the longitudinal study. Although the survivors were younger, more active, and perceived themselves in better health than the nonparticipants, their upper extremity performance significantly decreased in the 3-year period, with a few exceptions. In general, the decline was related to the initial score but not to age.

Quality of care in unlicensed homes for the aged in the eastern townships of Quebec

BACKGROUND

The recent proliferation of unlicensed homes for the aged in Quebec, coupled with the increased needs of the population they serve, has raised concerns about the quality of case these homes provide. The authors compared the quality of care in unlicensed homes with that in licensed long-term care facilities in a region of Quebec.

METHODS

The study involved 301 impaired people aged 65 and over in 88 residential care facilities (52 unlicensed, 36 licensed) in the Eastern Townships of Quebec. Study participants were chosen according to a 2-stage sampling scheme: stratified sampling of the primary units (facilities) and random sampling of the secondary units (residents). Quality of care was measured using the QUALCARE scale, a multidimensional instrument that uses a 5-point scale to assess 6 dimensions of care: environmental, physical, medical management, psychosocial, human rights and financial. A mean score of more than 2 was considered indicative of inadequate care.

RESULTS

Overall, the quality of care was similar in the unlicensed and licensed facilities (mean global score 1.61 [standard error of the mean (SEM) 0.06] and 1.47 [SEM 0.09] respectively). Examination of dimension-specific quality-of-care scores revealed that the unlicensed homes performed worse than the licensed facilities in 2 areas of care: physical care (mean score 1.80 [SEM 0.08] v. 1.51 [SEM 0.09] respectively, p = 0.017) and medical management (1.37 [SEM 0.06] v. 1.14 [SEM 0.05], p = 0.004). The dimension-specific scores also revealed that both types of homes lacked appropriate attention to the psychosocial aspect of care. Overall, 25% of the facilities provided inadequate care to at least one resident. This situation was especially prevalent among homes with fewer than 40 residents, where up to 20% of the residents received inadequate care.

INTERPRETATION

Most of the unlicensed homes for the aged that were studied delivered care of relatively good quality. However, some clearly provided inadequate care.

Correlates of care quality in long-term care facilities: a multilevel analysis

Hierarchical modeling was employed to explore correlates of the quality of care provided in long-term care facilities. For this purpose, a multilevel analysis offers two advantages over traditional analytical approaches. First, it accounts for the correlated nature of data recorded on multiple residents from the same facility. Second, it enables the investigators to study the influence of both resident and facility characteristics on care quality. The analysis was performed on data from 301 residents randomly sampled from 88 facilities located in the Province of Quebec, Canada. Results revealed that the presence of cognitive deficits was the strongest correlate of the quality of care provided to a resident. However, this relationship was found to vary significantly across facilities. Four facility-level variables were found to influence the relationship between cognitive functioning and care quality: the number of external collaborators the facility has, the type of training the facility manager has, the size of the facility, and the age distribution of its clientele. From these results, we suggest means to improve the quality of care provided to cognitively impaired older adults living in long-term care facilities.

Clinical outcome of cotransplantation of peripheral nerve and adrenal medulla in patients with Parkinson's disease. Clínica Puerta de Hierro Neural Transplantation Group

OBJECT

Transplants of adrenal medulla (AM) and fetal ventral mesencephalon (FVM) are currently being tested as therapeutic alternatives in patients with Parkinson's disease (PD). At the Clínica Puerta de Hierro in Madrid, a controlled clinical trial is underway to establish which donor tissue, if any, is the best for open surgical implantation in patients with PD.

METHODS

Since 1987, varying degrees of clinical improvement have been achieved in Grade IV and V parkinsonian patients by implanting perfused AM and FVM into the right caudate nucleus. To investigate further whether implantation of different types of donor tissues results in qualitatively and quantitatively different degrees of recovery, four patients with Grade IV or V PD received implants of pre-coincubated autologous AM and intercostal nerve in the caudate nucleus. Four nonsurgically treated patients served as a control group. Three years posttransplantation, longer on phases (46.2%+/-10.4% of the day presurgery to 87.5%+/-10.4% of the day 36 months postsurgery) and improved symptoms in on and off phases persist in all four cases, with reduced dyskinesias (67.1%+/-9.2% of the day in on phases presurgery to 17%+/-13.8% of the day in on phases 36 months postsurgery). Progress appears to be stepwise, starting within weeks of tranplantation and becoming clinically significant in the 2nd and 3rd months (similar to our AM- and sooner than in our FVM-implanted patients), followed by a period of stability and, after a second wave of improvement 12 to 18 months posttransplantation (similar to FVM implants), has continued (87.5+/-7 points presurgery to 46+/-5.6 points 36 months postsurgery). In the experimental group, doses of levodopa have been reduced by more than 60% and dopamine agonist use has not resumed. In contrast, there have been no significant clinical changes in the control group.

CONCLUSIONS

Implantation of tissue other than fetal tissue can promote a long-term improvement in the clinical symptomatology of seriously disabled parkinsonian patients. This finding is supported by the autopsy report of a patient with PD who had undergone grafting of AM plus peripheral nerve in which it was demonstrated that a large number of tyrosine hydroxylase-positive cells survive 1 year after implantation. In addition, there was a dense network of host dopaminergic fibers around the graft.