Innovative perspectives in limbic surgery using deep brain stimulation

Limbic surgery is one of the most attractive and retaken fields of functional neurosurgery in the last two decades. Psychiatric surgery emerged from the incipient work of Moniz and Lima lesioning the prefrontal cortex in agitated patients. Since the onset of stereotactic and functional neurosurgery with Spiegel and Wycis, the treatment of mental diseases gave attention to refractory illnesses mainly with the use of thalamotomies. Neurosis and some psychotic symptoms were treated by them. Several indications when lesioning the brain were included: obsessive-compulsive disorder, depression, and aggressiveness among others with a diversity of targets. The indiscriminately use of anatomical sites without enough scientific evidence, and uncertainly defined criteria for selecting patients merged with a deficiency in ethical aspects, brought a lack of procedures for a long time: only select clinics allowed this surgery around the world from 1950 to the 1990s. In 1999, Nuttin et al. began a new chapter in limbic surgery with the use of Deep Brain Stimulation, based on the experience of pain, Parkinson's disease, and epilepsy. The efforts were focused on different targets to treat depression and obsessive-compulsive disorders. Nevertheless, other diseases were added to use neuromodulation. The goal of this article is to show the new opportunities to treat neuropsychiatric diseases.

Neuropathic Pain and Positive Sensory Symptoms in Brachial Plexus Neuropathy: An Exploratory Study of Outcomes after Surgical Decompression and Proposal of a New Sensory Frequency of Symptoms Scale

BACKGROUND

There are no articles that aim to evaluate the specific role of surgical decompression on the recovery of pain and positive sensory symptoms (PSS) in patients with brachial plexus neuropathy (BPN), as well as the relationship between pain and frequency of sensory manifestations.

METHODS

A prospective before and after study was performed, considering the pain intensity through the visual analogue scale (VAS), and the frequency of PSS through a proposed new scale: Sensory Frequency of Symptoms Scale (SFSS). To compare the patients before and after the intervention, a paired T-test, a Wilcoxon signed-rank test, and Cohen's D test were made, coupled with a Spearman analysis in order to establish the relationship between pain and PSS.

RESULTS

Sixteen patients were included in the study, the clinical evaluation showed changes in pain according with VAS, going from a mean preoperative state of 8.19 to 1.31 after surgery, showing significant changes (84%, p < 0.00006, Δ = 2.776). Within the PSS, a significant decrease was observed in paresthesias (74%, p < 0.0001, Δ = 1.645), dysesthesias (80%, p < 0.002, Δ = 1.453), and allodynia (70%, p = 0.031, Δ = 0.635). Conversely, the preoperative correlation analysis between pain and dysesthesias/allodynia showed a low and non-significant relationship (R < 0.4, p > 0.05).

CONCLUSIONS

Surgical decompression is an effective technique for the relief of pain and sensory manifestations in adult patients with BPN of compressive origin. No relationship was observed between pain and dysesthesias/allodynia. Therefore, during clinical evaluation, they should be considered as independent manifestations, highlighting the need to validate new scales.

Effect of unilateral amygdalotomy and hypothalamotomy in patients with refractory aggressiveness

Background

Neurosurgical treatment, although controversial, is considered a useful resource in the treatment of chronic psychiatric diseases such as refractory aggressiveness.

Objective

To evaluate the clinical results and side effects of posteromedial hypothalamotomy associated with amygdalotomy in patients with refractory aggressiveness.

Method

A clinical trial was conducted in patients with chronic aggressiveness and refractory to pharmacological treatment. A central amygdalotomy associated with posteromedial hypothalamotomy was performed using thermo-coagulation by radiofrequency. The degree of aggressiveness was quantified by the Yudofsky's global scale of aggression. Postoperative changes in aggressive behavior continued to be evaluated every 6 months for at least 36 months.

Results

A statistically significant change in aggressive behavior was observed during 36 months of follow-up. The collateral effects of the association of both procedures are described, the most frequent being drowsiness and some cases of reduction in sexual behavior.

Conclusion

Symmetric and simultaneous unilateral lesions of the central nucleus of the amygdala and the posteromedial hypothalamus contralateral to motor dominance give the same clinical effect in the reduction of the pathological aggression that the bilateral lesions.

[Efecto de la amigdalotomía e hipotalamotomía unilateral en pacientes con agresividad refractaria]

Background

Neurosurgical treatment, although controversial, is considered a useful resource in the treatment of chronic psychiatric diseases such as refractory aggressiveness.

Objective

To evaluate the clinical results and side effects of posteromedial hypothalamotomy associated with amygdalotomy in patients with refractory aggressiveness.

Method

A clinical trial was conducted in patients with chronic aggressiveness and refractory to pharmacological treatment. A central amygdalotomy associated with posteromedial hypothalamotomy was performed using thermo-coagulation by radiofrequency. The degree of aggressiveness was quantified by the Yudofsky's global scale of aggression. Postoperative changes in aggressive behavior continued to be evaluated every 6 months for at least 36 months.

Results

A statistically significant change in aggressive behavior was observed during 36 months of follow-up. The collateral effects of the association of both procedures are described, the most frequent being drowsiness and some cases of reduction in sexual behavior.

Conclusion

Symmetric and simultaneous unilateral lesions of the central nucleus of the amygdala and the posteromedial hypothalamus contralateral to motor dominance give the same clinical effect in the reduction of the pathological aggression that the bilateral lesions.

La radiochirurgie dans le traitement des cavernomes. Expérience de 17 lésions traitées chez 15 patients

The aim of this study is to assess the efficiency of radiosurgery (RS) in the treatment of brain cavernomas. The series included intra-axial 17 lesions in 15 patients, 10 women and 5 men. Eleven were infratentorial lesions (brain stem and cerebellum) and 6 supratentorial (thalamus, hippocampus, brain cortex and paraventricular region). Fifteen lesions bled once or twice. Two lesions revealed by focal epilepsy displayed a rim of hemosiderin on MRI. RS was performed for all 17 lesions. The risk of morbidity was considered too high for surgery in 13 patients and 2 patients wished to be treated by RS. RS was delivered by a 6 MeV linear accelerator with a conic collimators device. Stereotactic localization and dosimetry were carried out with STP system 3.O (Fischer-Liebinger TM, Germany). Doses ranged between 16 and 23 Gy, the lower doses being delivered to brain stem lesions. All the lesions received a single fraction isocentric radiation. Lesion volumes ranged between 0.7 and 4.7 cm(3). Twelve lesions disappeared on MRI, the volume reduced (50-80%) in 3 lesions, and did not change in 2 lesions. Volume reduction was significant (P<0.01, P<0.001). In the follow up, 4 patients experienced bleeding, 1 of them died. Edema diagnosed in 2 patients at 3 and 13 months was treated by corticosteroids. The risk of hemorrhage without treatment in this group of patients was estimated about 34.45% a year. Hemorrhage incidence observed after RS was 7.17% (significant with P<0.01, P<0.001). At the end of follow up, 12 patients were symptom-free, 2 had sequels from bleeding, 1 patient died. Radiosurgery is an efficient treatment of cavernomas leading to a total disappearance of 70% of the lesions and significantly reducing the risk of new hemorrhages.

[Botulin toxin as treatment for spasticity and dystonia in infantile cerebral paralysis]

Treatment of spasticity and dystonía in PCI with Botulinum toxin A.

BACKGROUND

Botulinum-A (NxTxBoA) toxin produce neuromuscular blockade, it has been effective with therapeutic purposes in strabismus, focal dystonias and spasticity.

OBJECTIVE

Evaluate the therapeutically effects off NxTxBoA in cerebral palsy (CP) spastic and/or dystonic in children. Prospective study.

MATERIAL AND METHODS

12 CP patients (8 spastic and 4 spastic/dystonic) were treated with NxTxBoA in affected muscles at least for 2 doses by up 12 months. The indication was: improve limb function, to avoid surgical correction or improve hygienic or dressing. Ashworth Spasticity Scale (ASS), functional scale for Dystonic Sindou-Millet (SMS) and O'Brien Global Assessment Scale (OGAS) were used to evaluate improvement.

STATISTICAL METHODS

No parametric tests, Wilcoxon's rang's test and sign test were used with p < 0.05.

RESULTS

Total doses session was 3-10 U/kg. AAS showed muscle spasticity improvement in two grades in 8 patients, and one grade in the rest (p = 0.004). SMS showed the muscle dystonic improve up 60% in two patients improve 50% in others (p = 0.006). OGAS demonstrated a good correlation. Mean treatment effect during 4.8 months (rank 4 to 10 m). Two patients had side effects, general weakness, instability, and focal haematoma.

CONCLUSIONS

Botulinum toxin type A proved a highly useful adjuvant therapy and conservative management in CP.