Search

BACKGROUND AND PURPOSE: Tractography of the facial nerve based on single-shell diffusion MR imaging is thought to be helpful before surgery for resection of vestibular schwannoma. However, this paradigm can be vitiated by the isotropic diffusion of the CSF, the convoluted path of the facial nerve, and its crossing with other bundles. Here we propose a multishell diffusion MR imaging acquisition scheme combined with probabilistic tractography that has the potential to provide a presurgical facial nerve reconstruction uncontaminated by such effects. MATERIALS AND METHODS: Five patients scheduled for vestibular schwannoma resection underwent multishell diffusion MR imaging (b-values = 0, 300, 1000, 2000 s/mm2). Facial nerve tractography was performed with a probabilistic algorithm and anatomic seeds located in the brain stem, cerebellopontine cistern, and internal auditory canal. A single-shell diffusion MR imaging (b-value = 0, 1000 s/mm2) subset was extrapolated from the multishell diffusion MR imaging data. The quality of the facial nerve reconstruction based on both multishell diffusion MR imaging and single-shell diffusion MR imaging sequences was assessed against intraoperative videos recorded during the operation. RESULTS: Single-shell diffusion MR imaging–based tractography was characterized by failures in facial nerve tracking (2/5 cases) and inaccurate facial nerve reconstructions displaying false-positives and partial volume effects. In contrast, multishell diffusion MR imaging–based tractography provided accurate facial nerve reconstructions (4/5 cases), even in the presence of ostensibly complex patterns. CONCLUSIONS: In comparison with single-shell diffusion MR imaging, the combination of multishell diffusion MR imaging–based tractography and probabilistic algorithms is a more valuable aid for surgeons before vestibular schwannoma resection, providing more accurate facial nerve reconstructions, which may ultimately improve the postsurgical patient’s outcome.

Background Primary osteosarcoma of craniovertebral junction is extremely rare and reports in paediatric patients are limited. The symptoms are subtle and mostly underestimated. Case presentation. We present an unusual case of a 11-years old girl affected by an extensive and metastatic osteosarcoma of the atlas presented with cervicalgia and right torticollis refractory to medical treatment. The patient underwent open biopsy confirming the malignant histology. Conclusions Cervicalgia with or without a torticollis refractory to medical treatment, in absence of history of fell or trauma, is highly suspicious and should be considered as a warning sign for a severe pathology and it should not be neglected.

In vestibular schwannoma surgery, the preservation of facial and cochlear nerves is of paramount concern regarding to their effect on patients' quality of life. The rate of nerve function preservation has increased with advancements in surgical technique and neuroimaging and the introduction of intraoperative neuromonitoring. The preoperative depiction of anatomical issues between the nerves and tumor could help in surgical planning. Many studies investigating advanced imaging for cranial nerves detection, in particular diffusion tensor imaging, have been reported in the past decade. A systematic review of the reported data evaluating preoperative facial nerve fiber tracking, followed by intraoperative verification, was conducted. Seventeen studies with 223 patients (mean age, 47.5 years; range 17-77; male/female ratio 1:1.4) met our inclusion criteria. Preoperative facial nerve fiber tracking was obtained for 214 patients (96%), and subsequent intraoperative verification revealed a correct prediction for 187 cases (85.5%). The results from the present review have confirmed that preoperative fiber tracking for facial nerve identification during large vestibular schwannoma surgery is valuable and reliable. However, the included studies were not comparable in terms of images, acquisitions, or postprocessing elaboration. Larger series and homogenous magnetic resonance imaging parameters are required to strengthen these findings.

The choice between sitting and prone position to access the infratentorial space in a suboccipital craniotomy is still a matter of debate. The comparisons in terms of complications and outcome of both positions are scarce, and the pediatric population is indeed more infrequent in these in scientific reviews. In this paper, we assess intraoperative and postoperative complications and neurological outcome in pediatric patients undergoing posterior cranial fossa surgery for pilocytic astrocytoma in sitting and prone position respectively. We retrospectively analyzed 30 consecutive patients undergoing surgery for cerebellar pilocytic astrocytoma at the two neurosurgical units referring to the University of Padova Medical School from 1999 to 2017. Preoperative, intraoperative, and postoperative data were retrieved from our medical archives. The statistical analysis did not show any differences between the two groups in terms of preoperative, intraoperative, and postoperative data. The neurological status at last follow-up was similar in both groups of patients. Our results suggest that both sitting and prone position can be considered safe in suboccipital craniotomies. Further studies are needed to show if there are possible differences between these positions for other frequent pediatric tumors such as medulloblastomas and ependymomas.

Calvaria defects in children present a reconstructive challenge. When autogenous bone is not available, synthetic materials can be used; however, they present many drawbacks limiting their use in infants. Children, especially under the age of two, represent an incomparable limitation and they are infrequently reported in literature. The reconstructive strategies presented in the last decades are different without a clear consensus about the best procedure and material for a specific range of age. We report our experience with resorbable mesh cranioplasty using a polylactic acid / polyglycolic acid resorbable mesh plate with bone matrix in a 3-month old child who previously underwent decompressive craniectomy. This reconstructive strategy failed, and the patient was scheduled for a second procedure. After the case presentation, the literature is reviewed and discussed focusing on infants and young children. Keywords: Craniectomy, Cranioplasty, Infant, Resorbable mesh

Neurocysticercosis is the most frequent parasitic disease of the central nervous system, and its incidence in the developed countries is increasing due to immigration and travels from endemic areas. The intraventricular location has been found to involve up to 61.3% of the patients; moreover, only 22 cases of migrating intraventricular cyst have been reported so far. Despite the rarity of the condition in western countries, its occurrence generates some concerns and the aim of this paper is to update the information concerning pathogenesis, clinical presentation, diagnosis and management of this entity. All the pertinent literature was analysed, focused on the cases of migrating intraventricular neurocysticercosis and its peculiar features. An illustrative case regarding a 14-year-old girl is also presented. Migrating intraventricular neurocysticercosis is a pathognomonic entity usually presenting with hydrocephalus, and its treatment is mainly surgical, preferring an endoscopic approach. When the resection of the intraventricular cyst is not performed, an accurate follow-up is mandatory to detect clinical changes due to a recurrent hydrocephalus or to the effect of the dying cyst on the surrounding area. In case of permanent shunt placement, the cysticidal and steroid treatment is recommended to reduce the risk of shunt failure.

Status dystonicus (SD) is a rare and potentially life-threatening condition requiring intensive care management. Deep brain stimulation (DBS) has emerged as an effective treatment for SD refractory to medical management, but its application in this field is still limited. Here, we report the long-term outcome of four pediatric patients treated with DBS at the University Hospital of Padua, Italy, for SD refractory to medications. In addition, we present the results of a systematic literature review aimed at identifying published cases of SD treated with DBS, with focus on motor outcome. In our cohort, two children were affected by methylmalonic acidemia and suffered acute basal ganglia lesions, while the other two carried a pathogenic mutation in GNAO1 gene. DBS target was subthalamic nucleus (STN) in one case and globus pallidus internus (GPi) in three. All patients experienced SD resolution within 8–19 days after surgery. Mean post-operative follow-up was 5 years. We identified in the literature 53 additional SD cases treated with DBS (median age at DBS implantation: 12 years) with reported positive outcome in 51 and resolution of SD in a mean of 17 days after surgery. Our findings indicate that DBS is an effective treatment for SD refractory to medications, even in patients with acute basal ganglia lesions; STN can be an appropriate target when GPi is damaged. Moreover, data from long-term follow-up show that SD recurrences can be significantly reduced in frequency or abolished after DBS implantation.

Purpose Status Epilepticus can be a serious life threatening event in epileptic patients. The definition of refractory or super-refractory Status Epilepticus was based on the therapeutic response to anti-epileptic and anesthetic drugs. Vagal Nerve Stimulation showed efficacy in treating drug-resistant epilepsy but there are only few reports on emergentplacement of Vagal Nerve Stimulator for refractory or super-refractory Status Epilepticus. Methods Among 49 children implanted at our Institution with Vagal Nerve Stimulation for drug-resistant epilepsy, the authors retrospectively identified those implanted for refractory or super-refractory Status Epilepticus, according with the current definitions. Results 4 patients were operated upon at ages ranging 7 to 17 months and reached the programmed output current of 1 mA over a time ranging from 24 to 36 h (fast ramping-up). In 3 out of 4 patient we observed the abrupt of Status Epilepticus; one patient was refractory both to drugs and Vagal Nerve Stimulation and later died, without recovering from SE. At follow up, ranging from 24 to 45 months, the remaining 3 patients showed a decrease of the seizures frequency >80% without relapse of Status Epilepticus; in all the patients, output current and/or Duty Cycle were increased later. Conclusion VNS can be effective in treating refractory or super-refractory Status Epilepticus.

Vagal nerve stimulation (VNS) is an effective treatment for drug-resistant epilepsy that is not suitable for resective surgery, both in adults and in children. Few reports describe the adverse effects and complications of VNS. The aim of our study was to present a series of 33 pediatric patients who underwent VNS for drug-resistant epilepsy and to discuss the adverse effects and complications through a review of the literature. The adverse effects of VNS are usually transient and are dependent on stimulation of the vagus and its efferent fibers; surgical complications of the procedure may be challenging and patients sometimes require further surgery; generally these complications affect VNS efficacy; in addition, hardware complications also have to be taken into account. In our experience and according to the literature, adverse effects and surgical and hardware complications are uncommon and can usually be managed definitely. Careful selection of patients, particularly from a respiratory and cardiac point of view, has to be done before surgery to limit the incidence of some adverse effects.

Object Rubinstein-Taybi syndrome (RSTS) is a rare condition with characteristic genetic and clinical features. The presence of variable vertebral and neural axis abnormalities has been reported in the literature. We describe the possible association of multiple different spinal anomalies in these patients. Results The radiological exams of two RSTS patients (a female and male of 11 and 13 years) have been reviewed. Both patients presented the simultaneous association of craniovertebral junction bony abnormalities (occipito-C1 condyle subluxation and posterior C2-C3 arches fusion), Chiari I malformation, spinal cord syrinx, low-lying conus medullaris, and scoliosis. Conclusion An association of different spinal cord anomalies is possible in RSTS patients and has to be investigated with a comprehensive neuroimaging study in order to address the proper treatment and prevent the development of neurologic deficits. © Springer-Verlag 2012.

Background and purpose For many years deep brain stimulation (DBS) devices relied only on voltage-controlled stimulation (CV), but recently current-controlled devices have been developed and approved for new implants as well as for replacement of CV devices after battery drain. Constant-current (CC) stimulation has been demonstrated to be effective in new implanted parkinsonian and dystonic patients, but the effect of switching to CC therapy in patients chronically stimulated with CV implantable pulse generators (IPGs) has not been assessed. This report shows the results of a consecutive retrospective data collection performed at five Italian centers before and after replacement of constant-voltage with constant-current DBS devices, in order to verify the clinical efficacy and safety of this procedure. Methods Nineteen patients with Parkinson's disease or dystonic syndrome underwent DBS IPG CV/CC replacement. Clinical features and therapy satisfaction were assessed before surgery, 1 week after and 3 and 6 months after replacement. Programming settings and impedances were recorded before removing the CV device and when the CC IPGs were switched on. Results The clinical outcome of CC stimulation was similar to that obtained with CV devices and remained stable at 3 and 6 months of follow-up. Impedance values recorded for CV and CC IPGs were similar. Ninety-five percent of patients and physicians were satisfied with mixed implants. No adverse events occurred after IPG replacement. Conclusion Replacing CV with CC IPGs is a safe and effective procedure. Longer follow-up is necessary to better clarify the impact of CC stimulation on clinical outcome after chronic stimulation in CV mode.

Background: Spinal cord stimulation (SCS) is a technique used worldwide to treat several types of chronic neuropathic pain refractory to any conservative treatment. The aim of this data collection is to enforce evidence of SCS effectiveness on neuropathic chronic pain reported in the literature and to speculate on the usefulness of the trial period in determining the long–term efficacy. Moreover, the very low percentage of undesired side effects and complications reported in our case series suggests that all implants should be performed by similarly well-trained and experienced professionals. Method: A multicentric data collection on a common database from 11 Italian neurosurgical departments started 3 years ago. Two different types of electrodes (paddle or percutaneous leads) were used. Of 122 patients, 73 % (N = 89) were submitted to a trial period, while the remaining patients underwent the immediate permanent implant (N = 33). Statistical comparisons of continuous variables between groups were performed. Results: Most of the patients (80 %) had predominant pain to their lower limbs, while only 17 % of patients had prevalent axial pain. Significant reduction in pain, as measured by variation in visual analogue scale (VAS) score, was observed at least 1 year after implantation in 63.8 % of the cases, 59.5 % of patients who underwent a test trial and 71.4 % of patients who underwent permanent implant at once. No statistical differences were found between the lower-limb pain group and the axial pain group. Conclusions: No relevant differences in long-term outcomes were observed in previously tested patients compared with patients implanted at once. Through this analysis we hope to recruit new centres, to give more scientific value to our results. © 2015, Springer-Verlag Wien

Introduction Dystonia is a movement disorder due to sustained muscle contractions that cause twisting and repetitive movements conditioning abnormal postures. Tardive dystonia generally follows long treatment with neuroleptics. An extreme condition called status distonicus may even be life threatening, determining spasm of axial musculature leading to respiratory or cardiac arrest. Bilateral pallidotomy provided significant benefit to dystonic symptoms in some patients; moreover, in recent years, pallidotomy has been replaced from pallidal DBS; pallidal DBS is particularly effective both in primitive generalized dystonia and in tardive dystonia consequent to neuroleptics. Objectives To report DBS for the treatment of severe iatrogenic dystonia refractory to medical treatment. Patient and methods A 19 years-old boy affected by severe behavior disorder was treated with neuroleptic drugs (haloperidole). After three years of treatment, appeared severe neck and axial dystonia with initial involvement of the extremities. The change in the pharmacological treatment led to an initial improvement, followed by a progressive and relentless worsening and loss of motor autonomy. The patient also experimented severe dysphagia and several episodes of ab-ingestis pneumonia. Anticholinergic and dopaminergic treatment failed to improve symptoms. The patient progressively felt in a generalized status distonicus. At admission, F-M DRS was 74. For this potentially threatening for life condition, he was candidated for bilateral GPi DBS. After stereotactic localization of ventro-mesial-posterior part of Gpi on volumetric isotropic T1 MRi coupled with Shaltenbrandt & Wahren atlas, bilateral DBS was performed in general sedation, with intraoperative neurophysiology. A couple of quadripolar electrodes were inserted and immediately connected with IPG (Activa RC Medtronic). Results Stimulation started during postoperative day 2. After initial adjustment of the stimulation parameters we appreciated a clear reduction in the intensity and frequency of dystonic spasms, without surgical complication or adverse effects. At discharge the patient was able to walk without help, no dysphagia has been complained for and dystonic spasms were absent. Stimulation parameters were settled as following: left GPi 1- case positive, 2.0 V, 210 μs, 130 Hz; right GPi 9-case positive, 2.0 V, 210 μs, 130 Hz. At one year follow-up F-M DRS is 20. Conclusion The role of DBS in secondary dystonia is still debated because of several failures; important factors in the surgical outcome are: the etiology of dystonia, the absence of skeletal deformity, younger age at surgery and shorter duration of disease. Another topic is the time of early efficacy of DBS, very varying among different reports, but generally considered in the span of weeks or months. Tardive dystonia, due to neuroleptic therapy, seems to be affected from DBS, better than other secondary forms. GPi DBS has also been described to be effective in the treatment of status distonicus and it is considered the treatment of choice in the acute management of this life-threatening condition. In this case we found a striking improvement in F-M DRS, since the first days, with prompt resolution of status distonicus. We suggest the indication to acute treatment with DBS in case of status distonicus in course of tardive dystonia.

We evaluated body weight changes in patients with Parkinson's disease (PD) after electrode implantation for deep brain stimulation (DBS) in the subthalamic nucleus (STN) in relation to clinical improvement. Thirty PD patients who received STN DBS were included (22 men, 8 women; mean age, 60.0 ± 7.1 years; mean PD duration, 13.5 ± 3.7 years; mean body mass index [BMI], 21.6 ± 3.0 kg/m2). Body weight, physical activity, and Unified Parkinson's Disease Rating Scale (UPDRS) scores were noted before and 3 and 12 months after the procedure. Significant weight gain occurred in 29 patients; the mean increase was 14.8 ± 9.8% of initial body weight in 1 year. Of the patients, 46.5% reported weight gain in the first 3 months, 21.4% gradual weight gain in the first 6 months, and 32.1% a slow increase for 1 year. Mean BMI increased up to 24.7 ± 3.7 kg/m2. After 1 year, mean UPDRS motor score improved significantly in off and in on; and therapy complications improved by 91.0 ± 17.0%. BMI changes at 3 and 12 months were significantly correlated to dyskinesia score changes, and levodopa dosage was not. In PD, STN DBS produces not only symptom control, but also weight gain. DBS candidates should be given nutritional counseling before the intervention to prevent rapid and/or excessive weight gain. © 2003 Movement Disorder Society

The α-synuclein gene (SNCA) multiplication causes autosomal dominant Parkinson's disease (PD). Particularly triplication, but also duplication, of the SNCA is associated with early-onset rapidly progressing parkinsonism with increased risk of cognitive impairment. There is no report about the effect and safety of Deep Brain Stimulation (DBS) in carriers of this mutation and, in general, data in patients with genetic parkinsonism are scarce. We report a one-year prospective follow-up of subthalamic nucleus (STN) DBS in a 46-year old female carrier of SNCA duplication who developed PD at the age of 41 years, and rapidly showed disabling motor fluctuations and dyskinesias refractory to pharmacological strategies. One year after surgery there was a clinically relevant improvement in motor features with a reduction of 64% in UPDRS III in "off medication" and a complete abolition of peak dose dyskinesias. Patient did not report procedure-related adverse events following STN-DBS except for stimulation-induced right foot dystonia relieved by modulating stimulation parameters. Postoperative cognitive testing showed a decline in executive functions, mostly verbal fluency and attention shifting, compared with presurgical assessment. STN-DBS is safe and effective in patients with SNCA duplication showing a clinical pattern similar to idiopathic PD. Our case suggests that clinical phenotype rather genotype is the main predictor for DBS outcome.

Deep brain stimulation (DBS) is an effective surgical treatment for advanced Parkinson's disease (PD), with significant advantages in morbidity-mortality and quality of life when compared to lesion techniques such as thalamotomy and/or pallidotomy. The procedure is indicated in patients with severe resting tremor, unresponsive to conventional medical treatment or with motor complications. The most commonly reported complications in the intra- and post-surgical period are aborted procedure, misplaced leads, intracranial haemorrhage, seizures and hardware complications, whereas in the long-term period, cognitive and psychiatric complications can be observed. The most important eligibility criteria for DBS are: a correct diagnosis of idiopathic PD, severity of illness, a consistent levodopa response and absence of cognitive impairment. Chronological age and mood disorders may be relative contraindications to be individually evaluated. Tremor, rigidity dystonias and dyskinesias improve dramatically after DBS; freezing, postural instability and falls remain unchanged, whereas verbal fluency and dysarthria are known to worsen.

Si descrive la procedura d'installazione ed il controllo di qualità di un sistema per neurochirurgia stereotassica, che utilizza la risonanza magnetica per il calcolo diretto delle coordinate dei «bersagli». L'applicazione clinica del sistema conferma la fattibilità degli interventi in condizioni di sicurezza, e la validità del metodo adottato per l'eliminazione degli artefatti di distorsione spaziale nelle immagini.

Object: Neurophysiologic monitoring during deep brain stimulation (DBS) interventions in the globus pallidus internum (Gpi) for the treatment of Parkinson's disease or primary dystonia is generally based upon microelectrode recordings (MER); moreover, MER request sophisticated technology and high level trained personnel for a reliable monitoring. Recordings of cortical visual evoked potentials (CVEPs) obtained after stimulation of the optic tract may be a potential option to MER; since optic tract lies just beneath the best target for Gpi DBS, changes in CVEPs during intraoperative exploration may drive a correct electrode positioning. Patients and methods: Cortical VEPs from optic tract stimulation (OT C-CEPs) have been recorded in seven patients during GPi-DBS for the treatment of Parkinson's disease and primary dystonia under general sedation. OT C-VEPs were obtained after near-field monopolar stimulation of the optic tract; recording electrodes were at the scalp. Cortical responses after optic tract versus standard visual stimulation were compared. Results: After intraoperative near-field OT stimulation a biphasic wave, named N40-P70, was detected in all cases. N40-P70 neither change in morphology nor in latency at different depths, but increased in amplitude approaching the optic tract. The electrode tip was positioned just 1 mm above the point where OT-CVEPs showed the larger amplitude. No MERs were obtained in these patients; OT CVEPs were the only method to detect the Gpi before positioning the electrodes. Conclusions: OT CVEPs seem to be as reliable as MER to detail the optimal target in Gpi surgery: in addition they are less expensive, faster to perform and easier to decode. © 2010 Elsevier B.V.

Prospective comparative long-term data on the effect of deep brain stimulation (DBS) of the subthalamic nucleus (STN) and continuous subcutaneous infusion of apomorphine (CSAI) in patients with advanced Parkinson disease (PD) are lacking. We report 5-year follow-up of 25 PD patients treated with either STN-DBS (n = 13) or CSAI (n = 12) who fulfilled CAPSIT-PD criteria. Cohorts were matched for disease duration and severity of motor complications. Baseline clinical and neuropsychological status did not differ among cohorts. Patients were assessed with the UPDRS, MMSE, HAMD-17 and Neuropsychiatric Inventory (NPI).Twelve subjects reached the 5-year follow-up with STN-DBS (one was lost at follow-up) versus two in the CSAI cohort. Drop-outs with CSAI were due to subcutaneous nodules (n = 2), insufficient control of motor fluctuations and dyskinesia (n = 4), death for unrelated reasons (n = 3) and one was lost at follow-up. Average apomorphine dose at last visit was 83.4 ± 19.2 mg/day and average treatment duration was 30 months. At 1-year as well as at last follow-up (intention-to-treat analysis), both therapies decreased daily off-time but only STN-DBS reduced dyskinesia duration and severity. Decrement of medications was greater with STN-DBS. There was a significant worsening of NPI after STN-DBS, primarily because four subjects developed apathy.

Background: Subthalamic deep brain stimulation has proved significant efficacy in the treatment of Parkinson disease. Adverse events, due to surgical and hardware-related complications, must be clearly addressed to properly balance the cost-effectiveness of the therapy. In addition, limited data exists about medical adverse events after surgery. Methods: One hundred forty-one patients undergoing subthalamic deep brain stimulation for Parkinson disease from 1998 to 2007 were considered. Medical records, operative notes, clinical findings at follow-up and final outcome were accurately recorded to identify surgical- and hardware-related complications, infections and delayed adverse medical events. Results: Five hundred twenty-two surgical procedures were performed, including electrodes positioning and impulse programmable generators implantation and substitutions. Mean follow-up of the patients was 4.6 years (9 months10 years). Surgical complications were observed in 5.6% of patients, including two hemorrhages (1.4%) and three (2.1%) inabilities to complete the surgical procedure. Medical delayed adverse events affected 1.4% of patients, with a patient having a fatal aspiration pneumonia. Infections were seen in 5.6% of patients; removal of the hardware was necessary in 3.6%. Hardware-adverse events were observed in 7% of patients, generally requiring minor surgery. Direct surgical mortality was 0%; overall mortality was 0.7% and permanent surgical morbidity was 0.7%. Conclusions: Deep brain stimulation can be regarded as a safe procedure. Mortality and permanent morbidity are very low, and surgical complications are relatively rare. Nevertheless, minor complications are not infrequent; hence the importance of continuous monitoring of the patients during the follow-up period. © 2010 Elsevier Inc.

PURPOSE: A major stroke after carotid endareterectomy (CEA) is an event that should be managed according to a planned strategy. Literature data on this issue are not definitive. We reviewed our series in the attempt to define an algorithm of treatment if this complication occurs. METHODS: A consecutive series of 413 CEAs in 390 patients was considered. All operations were performed under general anaesthesia and EEG monitoring. An indwelling shunt was inserted only according to EEG changes. Direct closure of the arteriotomy was performed in all cases. Intraoperative ultrasound was not routinely employed before 2004. Patients who suffered from the new onset of an ischaemic hemispheric deficit or the worsening of a pre-existing deficit within 72 h after surgery were included in the present study. RESULTS: Sixteen patients (3.9%) suffered from perioperative stroke. Seven patients presented neurological deficits that rapidly and spontaneously resolved. In nine cases (2.2%) a major stroke occurred. Acute occlusion of the internal carotid artery (ICA), with or without embolic blocking of the omolateral M1 segment, occurred in eight cases; in one case a patent ICA was associated with the occlusion of two frontal branches of the omolateral middle cerebral artery. Seven cases were reoperated on. The ICA was reopened in all these cases except one. Among these seven cases, three (42%) had a good outcome. CONCLUSIONS: A major stroke after CEA is caused, in most of cases, by the acute ICA occlusion with or without intracerebral embolic occlusion. Reopening of the occluded ICA gives good results when intracerebral vessels are patent and when the occluded ICA is satisfactorily reopened. An algorithm of planned reactions in case of perioperative stroke is finally proposed.

BACKGROUND: High-frequency stimulation of the subthalamic nucleus (STN-DBS) improves motor symptoms in advanced Parkinson's disease (PD), but the mechanisms are still unclear. Functional imaging evidenced pathological overactivity in motor cortical areas in advanced PD that can be normalized by effective therapies. PATIENTS AND METHODS: We studied resting state cerebral blood flow pre-operatively and 12 months after surgery in 40 patients with advanced PD using ECD-SPECT. SPECT scans were also acquired 1 year apart in 21 matched PD controls who did not undergo surgery. Statistical analysis was performed using statistical parametric mapping (SPM2) software. In addition, we correlated brain perfusion changes after surgery with clinical improvement, assessed using the unified PD rating scale motor score (UPDRS-III). RESULTS: Patients showed marked motor improvement and medication reduction after surgery. Stimulated PD patients revealed bilateral rCBF decrements in motor cortical areas and prefrontal cortex bilaterally compared to pre-surgical condition as well as versus PD controls (p

We prospectively evaluated 20 patients with Parkinson's disease (PD) preoperatively and 12 months after subthalamic nucleus-deep brain stimulation (STN-DBS). All patients had clinical (UPDRS III) and neuropsychological evaluations as well as brain perfusion SPECT-ECD. Clinical and cognitive data were compared with 12 matched PD patients who had not undergone surgery. STN-DBS patients improved in motor symptoms and reduced medications but selectively declined in category fluency (p

A decline in verbal fluency is the most consistent neuropsychological sequela of deep brain stimulation (DBS) for Parkinson's disease. We assessed clinical correlates and switching and clustering subcomponents in 26 parkinsonians undergoing subthalamic DBS. Post-surgical motor improvement was accompanied by worsening at both letter and category fluency tasks. Total number of words and switches decreased, while average cluster size was unchanged. Worsening tended to be prominent in patients with baseline poorer cognitive status and more depressed mood. Impairment of shifting suggests prefrontal dysfunction, possibly due to disruption of fronto-striatal circuits along the surgical trajectory and/or to high frequency stimulation itself.

Background: The clinical condition of advanced Parkinson's disease ( PD) patients is often complicated by motor fluctuations and dyskinesias which are difficult to control with available oral medications. Objective: To compare clinical and neuropsychological 12 month outcome following subcutaneous apomorphine infusion (APO) and chronic deep brain stimulation of the subthalamic nucleus (STN-DBS) in advanced PD patients. Methods: Patients with advanced PD and medically untreatable fluctuations underwent either APO (13 patients) or STN-DBS (12 patients). All patients were clinically (UPDRS-III, AIMS, 12 h on-off daily) and neuropsychologically (MMSE, Hamilton-17 depression, NPI) evaluated at baseline and at 12 months. APO was discontinued at night. Results: At 12 months APO treatment (74.78 +/- 24.42 mg/day) resulted in significant reduction in off time ( 251%) and no change in AIMS. Levodopa equivalent medication doses were reduced from 665.98 +/- 215 mg/ day at baseline to 470 +/- 229 mg/ day. MMSE, NPI, and Hamilton depression scores were unchanged. At 12 months STN-DBS resulted in significant clinical improvement in terms of reduction in daily off time (276%) and AIMS (281%) as well as levodopa equivalent medication doses (980 +/- 835 to 374 +/- 284 mg/ day). Four out of 12 patients had stopped oral medications. MMSE was unchanged (from 28.6 +/- 0.3 to 28.4 +/- 0.6). Hamilton depression was also unchanged, but NPI showed significant worsening (from 6.58 +/- 9.8 to 18.16 +/- 10.2; p < 0.02). Category fluency also declined. Conclusions: Both APO and STN- DBS resulted in significant clinical improvement in complicated PD. STNDBS resulted in greater reduction in dopaminergic medications and provided 24 h motor benefit. However, STN-DBS, unlike APO, appears to be associated with significant worsening on NPI resulting from long term behavioral problems in some patients.

Objective Subthalamic (Stn) deep brain stimulation (DBS) is a valid surgical therapy for the treatment of severe Parkinson's disease. In recent years, StnDBS has been proposed for patients who previously received other surgical treatments, such as thalamotomy and pallidotomy. Nonetheless, there is no consensus about the indications of DBS in patients who previously underwent surgery. To the best of our knowledge this is the first reported case of a patient treated with DBS after previous thalamotomy and adrenal grafting. Clinical presentation A 62-year-old man with a long history (more than 30 yr) of Parkinson's disease received unilateral thalamotomy and autologous adrenal graft on two independent occasions. Thalamotomy led to a significant improvement, although limited to the control of contralateral tremor. The autologous adrenal graft was of no benefit. For the subsequent occurrence of L-dopa related dyskinesias and severe "off" periods, the patient was referred to our center for StnDBS. Intervention The patient underwent bilateral StnDBS, obtaining a satisfactory improvement of rigidity and bradykinesia on both sides. The 1-year follow-up evaluation showed a 46% improvement in the Unified Parkinson's Disease Rating Scale motor section, along with a noticeable reduction in antiparkinsonian therapy (81%). Conclusion This case is consistent with previous reports from the literature, suggesting that StnDBS is feasible and safe, even in patients who previously received other surgical treatments for Parkinson's disease, such as thalamotomy or cell grafting.

deep brain stimulation is a widely accepted surgical therapy for the symptomatic treatment of advanced parkinson's disease; high frequency chronic stimulation of the subthalamic nucleus proved its efficacy to control the major motor symptoms. In the neurosurgical department of Monza we treated 72 parkinsonian patients (November 1998–January 2003). One year follow-up results are: decrease of tremor 90%, hypertonous 56%, bradykinesia 70%, voice impairment amelioration 30%, mean total daily L-dopa intake reduced 58%. Freezing and balance did not ameliorate, some voice impairment and psychic derangement have been observed. Major surgical complications were: haemorrage (1 case – transient hemiparesis), infections (2 cases), pulmonary embolisation (1 case). To optimise the surgical results, careful clinical and instrumental selection of the patients are mandatory before surgery.

Background. Stereotactic localisation of proper targets can be obtained with Magnetic Resonance imaging (MRI), pending correction of the well-known inaccuracy of MRI in reproducing exact geometrical dimension. The aim of the experimental work was to determine the real extent of the MRI distortion and to correct it. Methods. PVC phantoms and fixed human brains were used as target simulators; stereotactic targeting was obtained with CT and MRI; the results were compared and, finally, the real stereotactic values were measured on a commercial stereotactic device. To optimise MRI targeting it was necessary to abate the “chemical-shift”, to modify the head-coil receiver (tuning the “off-resonance” frequencies) and to correct the targeting directly on the images (especially for the Y axis values); careful quality control and environmental tests were also necessary to maintain good performances along the time. Results. 172 measurements were carried out using both CT, plain X-ray and MRI on PVC phantom. The values obtained from CT were considered as reference. Significant geometrical accuracy was found with CT targeting, except for the Z co-ordinate, due to the slice thickness. Mean value differences between the targets on MRI and their real geometric position are about 1 mm on X and Z axises and about 2 mm on Y axis. Similar results were obtained on fixed brains, where absolute values of X and Y co-ordinates of the simulators were measured using a millimetre grid placed over the brain slice. Interpretation. Experimental findings concerning stereotactic targeting with MRI suggest accuracy adequate for clinical practice, even when extreme geometrical precision is required, such as in radiosurgery or functional stereotaxy. Careful quality control and intensive experimental setting of the MRI device are mandatory to obtain satisfactory results.

Deep brain stimulation (DBS) obtains good control of advanced PD symptoms. Chronic stimulation of Stn may alleviate rigidity, dyskinesia and tremor. Anatomical and functional intraoperative mapping are mandatory to obtain careful target localisation. Per-operative macrostimulation was carried out in 22 patients undergoing bilateral DBS in Stn; a volume 6 mm above to 4 mm below Stn was explored. Positive, collateral and adverse effects were recorded every 2 mm. Results obtained during acute stimulation were correlated to anatomical data from stereotactic atlases. Our findings suggest a volume, encompassing the zona incerta, Forel's fields and the lowermost part of anterior thalamus, functionally homogeneous to Stn. In fact, the stimulation of this volume obtains reduction of PD symptoms comparable to Stn.

22 patients undergoing percutaneous microcompression of Gasserian ganglion for the treatment of trigeminal neuralgia were monitored intraoperatively by means of trigeminal evoked potentials (TEPs). The second trigeminal branch was stimu-lated at the maxillary foramen; evoked responses were recorded using subcutaneous electrodes placed over the scalp. TEPs presented several short-latency waves (called W1, W2, W3, P4, N5, P6, N10) which are generated before and after the ganglion (W1, W2, W3), in the brain stem (P4, N5, P6) and possibly in the cortex (N10); other waves occur within 150 ms after the stimulus (late waves). During compression, W1 did not change, while W2 and W3 as well as P4, N5, P6, N10 and late waves decreased in amplitude: this pattern was noted in the patients who presented with pain relief during the follow-up period. On the contrary, the patients who suffered from pain recurrence did not show similar intraoperative TEP changes. In conclusion, intraoperative TEP derangements may be related to the effectiveness of the compression on the Gasserian ganglion.

Near field brain stem evoked potentials (NF-BAEPs) were recorded by means of an intraparenchymatous electrode placed in the right mesencephalon, during a stereotactic-guided biopsy of a tumor. The traces were compared with far field BAEPs (FF-BAEPs) obtained intraoperatively with scalp electrodes. The findings suggest a peripheral origin of wave II, a bilateral source of wave III and a main contralateral source of wave IV, while wave V seems to take origin mainly from the homolateral upper brain stem. Some intraparenchymatous activities do not project to the scalp. The possible impairments of NF-BAEP due to the presence of the tumor and the challenges of unidimensional single electrode recording are discussed.

A new model of focal axonal injury was reproduced by rapid and controlled elongation (uniaxial stretch) of the guinea pig optic nerve. Light microscopy study of optic nerve specimens after horseradish peroxidase injection into the vitreous of the animal's eye showed that axonal lesions were identical to those seen in human and primate post-traumatic diffuse axonal injury (DAI). The lesions were characterized by the formation of terminal clubs in severed axons and focal axonal enlargements in those axons that were lesioned-in-continuity. Visual-evoked potentials upon flash stimulation were recorded before and after injury. Mean amplitude and mean latency of occipital peaks were significantly elongated in the acute post-traumatic phase. Electron microscopy examination showed that the main axonal changes observed in this model were cytoskeleton disorganization, accumulation of axoplasm membrane-bound bodies at the site of terminal balls and dilatations-in-continuity and detachment of the axolemma from the myelin sheath. Such axonal alterations were similar to those found in many other biological models of central and peripheral axonal injuries in which the lesion was produced by invasive methods. This model is unique since it reproduces the same mechanism of injury and the identical lesions that have been demonstrated in humans and primates with post-traumatic (DAI).

18 subjects with symptomless HIV infection were investigated with multimodal evoked potentials for possible CNS involvement and again after an 8-12 month interval. 13 subjects showed neuropsychological changes, which were confirmed at the second examination. The 5 subjects found normal remained so at the second examination. On WAIS assessment the only patient to earn pathological scores was the one with the greatest evoked potentials changes. Thus the evoked potentials procedure proved capable of identifying early CNS involvement by HIV infection.

Pattern-reversal visual evoked potentials (PR-VEPs) and EEG were recorded in 14 phenylketonuric (PKU) children on a low-phenylalanine (phe) diet; the data obtained were correlated with metabolic parameters, namely, the actual phe plasma level, the mean phe plasma level in the last year, an the beginning of the diet. PR-VEPs seem to be more sensitive than EEG in detecting neurophysiological derangements in these subjects; in fact PR-VEPs were pathological in six patients while EEG detected three; no significant alterations were found in the neurophysiological tests among the children with good metabolic control, and only one child was abnormal among the six on an early dietetic regimen; in contrast, six of the nine subjects presenting with high mean phe plasma levels (greater than 10 mg/100 ml) and five of the eight whose diet started after the 2nd month of life showed pathological PR-VEPs.

Visual evoked potentials (VEP) were recorded in 20 children undergoing dialysis for chronic renal failure. VEP before treatment (72 h after last dialysis) were pathological in 17 patients (85%); responses obtained 3 h after treatment were abnormal in only 6 cases (30%). Furthermore, all patients improved after treatment, except two who were unchanged. However, VEP recorded immediately after dialysis were worse in 4 of 7 patients than before treatment, probably as an effect of the dysequilibrium syndrome; they improved spontaneously afterwards. The acute changes caused by dialysis seem to be more evident in children than in adults. No correlations have been found between blood chemistry indexes and VEP modifications. Finally, VEP have proved to be more sensitive than EEG in identifying a central nervous system (CNS) dysfunction in these uremic patients.

Extradural motor cortex stimulation (EMCS) has been proposed as alternative to deep brain stimulation (DBS) in the treatment of Parkinson's disease (PD). Its mechanisms of action are still unclear. Neuroimaging evidenced motor cortical dysfunction in PD that can be reversed by therapy. We performed left hemisphere EMCS surgery in six advanced PD patients fulfilling CAPSIT criteria for DBS with the exception of age >70 years. After 6 months, we measured regional cerebral blood flow (rCBF) at rest with SPECT and Tc-99m cysteinate dimer bicisate off-medication with stimulator off and on. Clinical assessment included Unified Parkinson's Disease Rating Scale part II and III, Abnormal Involuntary Movement Scale and mean dopaminergic medication dosage. We used statistical parametric mapping for imaging data analysis. Clinically we observed no mean changes in motor scales, although blinded evaluation revealed some benefit in individual patients. We found significant rCBF decrements in the pre-central gyrus, pre-motor cortex and caudate nucleus bilaterally, left prefrontal areas and right thalamus. Perfusion increments were found in cerebellum bilaterally. EMCS determined significant modulation of neuronal activity within the cortico-basal ganglia-thalamo-cortical motor loop in our cohort of advanced PD patients. However, these effects were paralleled by mild and variable clinical efficacy.