Selective peripheral denervation: comparison with pallidal stimulation and literature review.

Patients with cervical dystonia who are non-responders to Botulinum toxin qualify for surgery. Selective peripheral denervation (Bertrand's procedure, SPD) and deep brain stimulation of the globus pallidus (GPi-DBS) are available surgical options. Although peripheral denervation has potential advantages over DBS, the latter is nowadays more commonly performed. We describe the long-term outcome of selective peripheral denervation as compared with GPi-DBS, along with the findings of literature review. Twenty patients with selective peripheral denervation and 15 with GPi-DBS were included. Tsui scale, a visual analogue scale, and the global outcome score of the Toronto Western Spasmodic Torticollis Rating Scale were used to define a "combined global surgical outcome". The "combined global surgical outcome" for patients with selective peripheral denervation or pallidal stimulation was respectively "bad" for 65 and 13.3 %, "fair-to-good" for 30 and 26.7 %, and "marked" improvement for 5 and 60 % (p < 0.001). Improvement on visual analogue scale (p < 0.002), global outcome score (p < 0.002), and Tsui score (p < 0.000) was larger for the pallidal stimulation group. Seventy-five percent of patients with selective peripheral denervation and 60 % of patients with pallidal stimulation reported side effects. Seven patients with selective peripheral denervation successively underwent GPi-DBS, with a further significant improvement in the Tsui score (-48.6 ± 17.4 %). GPi-DBS is to be preferred to selective peripheral denervation for the treatment of cervical dystonia because it produces larger benefit, even if it can have more potentially severe complications. GPi-DBS is also a valid alternative in case of failure of SPD.

Course of recovery and prediction of outcome in young patients in a prolonged vegetative or minimally conscious state after severe brain injury: An exploratory study.

AIMS: To explore the course of recovery of consciousness and factors predicting the outcome of severe brain injury with a prolonged period of unconsciousness in children and young adults receiving a specialized rehabilitation treatment, the Early Intensive Neurorehabilitation Programme (EINP). METHODS: A cohort of forty-four patients aged 1.6-25.5 years (M=16.0) with traumatic acquired brain injury (TBI) or non-traumatic acquired brain injury (nTBI) were examined using the Western Neuro Sensory Stimulation Profile every two weeks, from the application for EINP until discharge. The level of consciousness was assessed with the Post-Acute Level of Consciousness Scale, and the level of disability was determined by the Disability Rating Scale. Long-term level of disability of all TBI patients (N=32) was assessed between 2.0 and 4.4 years after discharge from EINP. RESULTS: Two-thirds of all patients recovered to consciousness. Three recovery patterns were identified: remaining in a vegetative state (VS), slow recovery of consciousness, and fast recovery of consciousness. In the long-term, 11 of the TBI patients were severely disabled, 13 were moderately disabled, and 4 were mildly disabled. All TBI patients who were in VS at discharge either had deceased, or recovered to a very severely disabled state. CONCLUSIONS: Three recovery patterns identified in an early stage after starting EINP made it possible to predict long-term level of disability.

Active stimulation site of nucleus accumbens deep brain stimulation in obsessive-compulsive disorder is localized in the ventral internal capsule.

Obsessive-compulsive disorder (OCD) is a chronic psychiatric disorder characterized by persistent thoughts and repetitive ritualistic behaviours. Despite optimal cognitive-behavioral and pharmacological therapy, approximately 10 % of patients remain treatment-resistant. Deep brain stimulation (DBS) is being investigated as experimental therapy for treatment-refractory OCD. In the current study, we determined the relationship between anatomical location of active electrode contacts and clinical outcome in 16 OCD patients undergoing bilateral nucleus accumbens (NAc) DBS. We found that most patients actually do not receive active stimulation in the NAc but in the more laterally, anteriorly and dorsally located ventral part of the anterior limb of the internal capsule, ventral ALIC (vALIC). Our nine patients receiving bilateral vALIC DBS improved on average 73 % on their Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) scores, whereas the six patients with their centers of stimulation located otherwise improved on average only 42 %. We therefore propose bilateral vALIC as a promising new DBS target for patients with treatment-refractory OCD. Future studies employing a direct vALIC targeting approach in larger patient numbers are needed to test whether this proposal holds true.

Long-term follow-up of thalamic stimulation versus thalamotomy for tremor suppression.

Thalamic stimulation and thalamotomy for treatment of tremor due to Parkinson's disease, essential tremor, and multiple sclerosis were compared in a randomized trial. The symptomatic and functional outcome was studied after 5 years of follow-up. Sixty-eight patients were treated (45 Parkinson's disease, 13 essential tremor, 10 multiple sclerosis) by thalamotomy (n = 34) or thalamic stimulation (n = 34). After 5 years, 48 patients were available for follow-up. The primary outcome measure was change in functional status measured by the Frenchay Activities Index (FAI), scores ranging from 0 to 60. Secondary outcome measures were tremor severity, frequency of complications, and patients' assessment of the outcome. The mean difference in FAI scores between thalamic stimulation and thalamotomy was 4.4 (95% CI: 1.1-7.7) after 6 months, 3.3 (95% CI: -0.03-6.6) after 2 years and 4.0 (95% CI: 0.3-7.7) after 5 years in favor of stimulation. Tremor suppression was equally effective after both procedures, and stable in Parkinson patients. In ET and multiple sclerosis, a diminished effect of stimulation was observed in half of the patients. There were six stimulation equipment-related complications, but neurological side effects of surgery were higher after thalamotomy. Subjective outcome-assessment by the patients was more favorable in the stimulation group.

Stimulation of the subthalamic region facilitates the selection and inhibition of motor responses in Parkinson's disease.

The aim of the present study was to specify the involvement of the basal ganglia in motor response selection and response inhibition. Two samples were studied. The first sample consisted of patients diagnosed with Parkinson's disease (PD) who received deep-brain stimulation (DBS) of the subthalamic nucleus (STN). The second sample consisted of patients who received DBS for the treatment of PD or essential tremor (ET) in the ventral intermediate nucleus of the thalamus (Vim). Stop-signal task and go/no-go task performances were studied in both groups. Both groups performed these tasks with (on stimulation) and without (off stimulation) DBS to address the question of whether stimulation is effective in improving choice reaction time (RT) and stop-signal RT. The results show that DBS of the STN was associated with significantly enhanced inhibitory control, as indicated by shorter stop-signal RTs. An additional finding is that DBS of the STN led to significantly shorter choice RT. The effects of DBS on responding and response inhibition were functionally independent. Although DBS of the Vim did not systematically affect task performance in patients with ET, a subgroup of Vim-stimulated PD patients showed enhanced stop-signal RTs in on stimulation versus off stimulation. This result suggests that the change in performance to stop signals may not be directly related to STN function, but rather results from a change in PD function due to DBS in general. The findings are discussed in terms of current functional and neurobiological models that relate basal ganglia function to the selection and inhibition of motor responses.

Direct access of drugs to the human brain after intranasal drug administration?

It has been suggested that intranasal (IN) drug delivery could be used to administer drugs directly to the brain, bypassing the blood-brain barrier. Conclusive evidence of this proposed route of drug transport has not been observed by IN-IV comparison. In eight neurosurgery patients with a CSF drain, the uptake in CSF and plasma after IN and IV drug administration was compared. No evidence of direct access of the drugs from the nose to the CSF was found.

Intraoperative monitoring of brain tissue oxygen and carbon dioxide pressures reveals low oxygenation in peritumoral brain edema.

Brain edema and swelling often complicate surgery for brain tumors. Its pathophysiology is unclear, as is the relationship with brain tissue oxygenation. Our hypothesis was that brain edema around tumor is cytotoxic type caused by impaired local tissue oxygenation due to increased local tissue pressure. Therefore, we monitored brain tissue oxygen pressure (p(ti)O2) and carbon dioxide pressure (p(ti)CO2) in 19 patients undergoing craniotomy for removal of a brain tumor and specifically studied the effect of decompression by dura opening and by tumor removal with respect to the presence of brain swelling. Before craniotomy, multiparameter sensors were inserted into the peritumoral brain tissue guided by MRI-based stereotaxy. In eight patients who had severe brain swelling upon opening of the dura mater, p(ti)O2 immediately rose from 7 +/- 8 mm Hg to 24 +/- 15 mm Hg ( < 0.05), whereas in patients who did not have swelling, p(ti)O2 went from 16 +/- 9 to 18 +/- 10 mm Hg after opening of the dura. The mean p(ti)O2 of all patients at the start of resection of the tumor was 18 +/- 11 mm Hg, and increased to 30 +/- 15 mm Hg after resection was completed ( < 0.05). The effect on p(ti)O2 of raising the FiO2 to 1.0 was limited in this group of patients, as an increase greater than 50% was found in only six of twelve patients. Notably, in six patients, sensor malfunctions or associated hardware problems occurred, prohibiting useful data acquisition. We conclude that brain tissue oxygenation is reduced in the peritumoral area and improves after local tissue pressure relief, especially in patients with brain swelling. Thus, ischemic processes may contribute to brain edema around tumors. Intraoperative p(ti)O2 monitoring may enhance the safety of neuroanesthesia, but the high incidence of failures with this type of sensor remains a matter of concern.

Bilateral pallidotomy in Parkinson's disease: a retrospective study.

We evaluated the effects of bilateral pallidotomy in patients with advanced Parkinson's disease. Thirteen patients with Parkinson's disease had a staged bilateral pallidotomy if they had severe response fluctuations, dyskinesias, painful dystonia, or bradykinesia despite optimum pharmacological treatment. Assessment scales were the Unified Parkinson's Disease Rating scale (UPDRS), the Schwab and England scale, and a questionnaire on the effects of disability in activities of daily living and adverse effects. Postoperative magnetic resonance imaging was evaluated for lesion location and extension. The median off-phase UPDRS motor score was reduced from 43.5 to 29 after the first pallidotomy, and it was further reduced to 23.5 after the second pallidotomy (n = 8). The UPDRS activities of daily living off-phase score improved from 28.5 to 20.5 after the first pallidotomy and to 19 after the second pallidotomy (n = 6). The Schwab and England scale off-phase score showed an improvement after both procedures, first from 40 to 60, and thereafter to 90 (n = 8). On-phase dyskinesias were reduced substantially. Eight patients had adverse effects, of whom five had problems with speech. One patient became hemiplegic due to a delayed infarction. Ten patients experienced further benefit from the second procedure. Bilateral pallidotomy reduces dyskinesias. A second contralateral pallidotomy may reduce parkinsonism, although to a lesser degree compared with the first pallidotomy and with an increased risk for adverse effects.

Expression and distribution of id helix-loop-helix proteins in human astrocytic tumors.

The Id family of helix-loop-helix proteins is involved in a variety of processes, such as development, proliferation, and angiogenesis. In this study, we investigated the expression pattern of Id1, Id2, and Id3 in surgical specimens of human glial tumors. Western blot analysis demonstrated that all three Id proteins were expressed in astrocytic tumors. Expression levels in high-grade tumors were higher than in low-grade tumors. Immunohistochemical analysis confirmed that many of the tumor astrocytes exhibited strong Id1-3 IR. In contrast, in adult human normal brain, Id expression was low both in resting astrocytes and in endothelial cells. In tumor cells, Id proteins displayed cytoplasmic as well as nuclear localization. Id1-3 IR scores in tumor cells were positively correlated with proliferation indices. Moreover, Id1-3 IR was detected in endothelial cells of the astrocytic tumor blood vessels. The vascular Id1-3 expression correlated positively with tumor vascularity and grade. These results support the role of the Id gene family in the enhanced proliferative potential of tumor astrocytes. The evidence also supports the involvement of the Id gene family in tumor angiogenesis, a process that critically influences the malignant behavior of glial tumors.

Stereotactic neurosurgery for tremor.

The role of the motor thalamus as surgical target in stereotactic neurosurgery for different kinds of tremor is discussed. For tremor in Parkinson's disease, the subthalamic nucleus becomes more and more often the surgical target, because this target also gives relief of other and more incapacitating symptoms (hypokinesia, rigidity). Stimulation is as effective in tremor suppression as coagulation but has less adverse events and permits bilateral surgery. In selected cases, thalamotomy can still be indicated.