Maria G. Cersosimo

Neural control of the gastrointestinal tract: Implications for Parkinson disease

Disorders of swallowing and gastrointestinal motility are prominent nonmotor manifestations of Parkinson disease (PD). Motility of the gut is controlled both by extrinsic inputs from the dorsal motor nucleus of the vagus (DMV) and paravertebral sympathetic ganglia and by local reflexes mediated by intrinsic neurons of the enteric nervous system (ENS). Both the ENS and the DMV are affected by Lewy body pathology at early stages of PD. This early involvement provides insights into the pathophysiology of gastrointestinal dysmotility in this disorder and may constitute an important step in the etiopathogenesis of Lewy body disease.

Quantitative Study of Salivary Secretion in Parkinson's Disease

We examined basal and reflex salivary flow rate and composition in 46 patients with Parkinsons disease (PD), both in off and on conditions, compared to 13 age‐matched controls without underlying disease or treatment affecting autonomic function. Whole saliva was collected 12 hours after withdrawal of dopaminergic drugs and at the peak of levodopa‐induced motor improvement. Twenty‐three of the 46 PD patients had received domperidone a week before the study. Basal salivary flow rate was significantly lower in PD patients in the off state compared to controls (P < 0.005). Levodopa increased salivary flow rate (P < 0.05) both in the domperidone‐pretreated and untreated groups. Citric acid stimulated salivary flow rate in both the off and on states in PD patients. This effect was higher in the domperidone‐pretreated patients. Salivary concentration of sodium, chloride, and amylase was higher in PD patients than in controls and was not affected by levodopa or domperidone treatment. Levodopa stimulates both basal and reflex salivary flow rate in PD. The mechanism appears to be central, as the effect is not blocked by domperidone. Domperidone may have a peripheral effect that potentiates reflex salivary secretion. Salivary composition is abnormal in PD and is not affected by levodopa treatment.

Pathological correlates of gastrointestinal dysfunction in Parkinson's disease

Gastrointestinal dysfunction is a prominent manifestation of Parkinsons disease (PD). Gastrointestinal symptoms in PD include reduced salivation, dysphagia, impaired gastric emptying, constipation, and defecatory dysfunction. Constipation may precede the development of somatic motor symptoms of PD for several years. Neuropathological studies show early accumulation of abnormal alpha-synuclein (α-SYN) containing inclusions (Lewy neurites) in the enteric nervous system (ENS) and dorsal motor nucleus of the vagus (DMV) both in PD and in incidental Lewy body disease (ILBD). These findings provided the basis for the hypothesis that α-SYN pathology progresses in a centripetal, prion-like fashion, from the ENS to the DMV and then to more rostral areas of the central nervous system. Colonic biopsies may show accumulation α-SYN immunoreactive Lewy neurites in the submucosal plexus of PD patients. Salivary gland involvement is prominent in PD and α-SYN pathology can be detected both at autopsy and in minor salivary gland biopsies.

Gastrointestinal manifestations in Parkinson’s disease: prevalence and occurrence before motor symptoms

To assess the prevalence of gastrointestinal symptoms (GIS) in Parkinson’s disease (PD) compared to control subjects and their timing of appearance in relationship to the onset of motor symptoms. There is a rostrocaudal gradient of alpha-synuclein (α-SYN) neuropathology in the enteric nervous system at early stages of PD with higher burden in the upper than the lower gut. However, only constipation has been recognized as a premotor gastrointestinal manifestation of PD. 129 PD patients and 120 controls underwent a structured questionnaire to assess the presence of GIS and, in PD patients, the time of their appearance respect to the onset of motor manifestations. GIS significantly more prevalent in PD patients were dry mouth, drooling, dysphagia, constipation and defecatory dysfunction. Constipation and defecatory dysfunction preceded motor manifestations. Whereas gastroparesis symptoms preceded motor manifestations, their prevalence was not significantly different from controls. Despite evidence of a higher α-SYN burden in the upper gut, only constipation and defecatory dysfunction were prominent premotor GIS of PD.

Autonomic involvement in Parkinson's disease: pathology, pathophysiology, clinical features and possible peripheral biomarkers.

Autonomic nervous system involvement occurs at early stages in both Parkinsons disease (PD) and incidental Lewy body disease (ILBD), and affects the sympathetic, parasympathetic, and enteric nervous systems (ENS). It has been proposed that alpha-synuclein (α-SYN) pathology in PD has a distal to proximal progression along autonomic pathways. The ENS is affected before the dorsal motor nucleus of the vagus (DMV), and distal axons of cardiac sympathetic nerves degenerate before there is loss of paravertebral sympathetic ganglion neurons. Consistent with neuropathological findings, some autonomic manifestations such as constipation or impaired cardiac uptake of norepinephrine precursors, occur at early stages of the disease even before the onset of motor symptoms. Biopsy of peripheral tissues may constitute a promising approach to detect α-SYN neuropathology in autonomic nerves and a useful early biomarker of PD.

Pallidal surgery for the treatment of primary generalized dystonia: Long-term follow-up

OBJECTIVE To describe the results and long-term follow-up after functional surgery of the internal segment of the globus pallidus (GPi) in 10 patients with primary generalized dystonia. PATIENTS AND METHODS Nine of the 10 patients were positive for the DYT1 gene mutation. Bilateral deep brain stimulation (DBS) of the GPi was performed in three cases, bilateral pallidotomy in two, and combined surgery (unilateral GPi lesion with contralateral stimulation) in the remaining five. All patients were evaluated with the Burke-Fahn-Marsden dystonia scale (BFMDS) before, immediately after surgery, at 3 weeks, 3 and 6 months and then yearly. Follow up time ranged from 15 to 105 months (mean: 66.1 months) with six patients having more than 6 years follow up. RESULTS All patients improved after surgery. All patients with unilateral or bilateral DBS experienced an immediate improvement before starting stimulation. The magnitude of this initial micro lesion effect did not predict the magnitude of the long-term benefit of DBS. The mean decrease in the in the BFMDS was 34%, 55%, and 65% in the movement scale; and 32%, 48%, and 49% in the disability scale for patients with bilateral pallidal DBS, combined unilateral DBS and contralateral pallidotomy, and bilateral pallidotomy, respectively. Worsening of dystonia after a plateau of sustained benefit was observed in three patients. Two patients required multiple pallidal surgeries. Adverse events included: permanent anarthria (1), misplacement of the electrode requiring further surgery (2), scalp infection (1), and hardware related problems (3). CONCLUSIONS This long-term follow up study confirms the beneficial effect of pallidal DBS or pallidotomy in primary generalized dystonia. In addition, our results extent previous observations by showing that, in these patients, (1) the microlesion effect of DBS is not predictive of long-term benefit; (2) combined DBS with contralateral pallidotomy appears to be more effective than bilateral pallidal DBS; and (3) dystonia can reappear after an initial good response during long term follow up.

Micro Lesion Effect of the Globus Pallidus Internus and Outcome with Deep Brain Stimulation in Patients with Parkinson Disease and Dystonia

To determine whether the immediate response to electrode implantation (micro lesion effect, MLE) in the internal segment of the globus pallidus (GPi) predicts symptom improvement with deep brain stimulation (DBS) at 6 months in patients with Parkinsons disease (PD) or generalized dystonia. Electrode implantation in the subthalamic nucleus (STN) prior to electrical stimulation has been reported to predict a beneficial effect of DBS in patients with PD, but whether this is also the case for the GPi in either PD or dystonia patients has not been established. We studied 20 patients (11 with PD and 9 with dystonia) who underwent electrode implantation in the GPi. Effects were assessed using standardized scales after 24 hours, weekly for 3 weeks prior to starting DBS, and after 6 months of DBS. 10 of 11 PD and 8 of 9 dystonia cases who benefited from electrode implantation also showed improvement in all motor and disability scores after 6 months of DBS of the GPi. One dystonia patient who did not show MLE benefited from DBS. The presence of MLE after electrode implantation in the GPi may help predict motor benefit from DBS in PD and generalized dystonia patients.

Hyposialorrhea as an early manifestation of Parkinson disease

We sought to determine whether hyposialorrhea is an early manifestation of Parkinson disease (PD). We measured basal and citric acid stimulated secretion of whole saliva in 20 patients with early stage (Hoehn-Yahr I-II) PD who had motor symptoms for less than 1 year and were on no medication and 11 age matched controls. Compared to controls, PD patients had significant reduction of both basal (0.0964+/-0.08 vs 0.293+/-0.112 ml/min, p<0.001) and reflex (0.263+/-0.213 vs 0.537+/-0.313 ml/min, p<0.001) salivary secretion. Our findings confirm that hyposialorrhea is an early autonomic manifestation of PD.

Holmes tremor: Clinical description, lesion localization, and treatment in a series of 29 cases.

Objective: To describe the clinical features, etiology, findings from neuroimaging, and treatment results in a series of 29 patients with Holmes tremor (HT). Methods: A retrospective study was performed based on review of medical records and videos of patients with HT diagnosis. Results: A total of 16 women and 13 men were included. The mean age at the moment of CNS insult was 33.9 ± 20.1 years (range 8–76 years). The most common causes were vascular (48.3%), ischemic, or hemorrhagic. Traumatic brain injury only represented 17.24%; other causes represented 34.5%. The median latency from lesion to tremor onset was 2 months (range 7 days–228 months). The most common symptoms/signs associated with HT were hemiparesis (62%), ataxia (51.7%), hypoesthesia (27.58%), dystonia (24.1%), cranial nerve involvement (24.1%), and dysarthria (24.1%). Other symptoms/signs were vertical gaze disorders (6.8%), bradykinesia/rigidity (6.8%), myoclonus (3.4%), and seizures (3.4%). Most of the patients had lesions involving more than one area. MRI showed lesions in thalamus or midbrain or cerebellum in 82.7% of the patients. Levodopa treatment was effective in 13 out of 24 treated patients (54.16%) and in 3 patients unilateral thalamotomy provided excellent results. Conclusions: The most common causes of HT in our series were vascular lesions. The most common lesion topography was mesencephalic, thalamic, or both. Treatment with levodopa and thalamic stereotactic lesional surgery seems to be effective.

Botulinum Toxin in a Case of Hemimasticatory Spasm With Severe Worsening During Pregnancy

Hemimasticatory spasm (HMS) is a rather uncommon movement disorder with a pathophysiology that is still unclear, although temporomasseter entrapment at the temporal fossa has been advanced. The authors present a case of HMS in a woman who experienced marked worsening in episode frequency and severity during pregnancy. Treatment with botulinum toxin led to marked improvement.