Benefits in pain perception, ability function and health-related quality of life in patients with failed back surgery syndrome undergoing spinal cord stimulation in a clinical practice setting.

BACKGROUND: Failed back surgery syndrome (FBSS) represents one main cause of chronic neuropathic or mixed pain, functional disability and reduced Health Related Quality of Life (HRQoL). Spinal Cord Stimulation (SCS) can be a value for money option to treat patients refractory to conventional medical management (CMM). We estimated from real-world data: 1) the amount of reduced levels of HRQoL of target patients compared to general population, 2) the relationship between pain intensity, functional disability, and overall HRQoL, and 3) the improvement of patients' health from SCS intervention, and 4) we give some insights and make some suggestions on the selection of a battery of patients' reported health instruments for use in routine clinical practice. METHODS: At recruitment (before SCS) and every 6 months for 2 years after SCS a battery of questionnaires/tests were completed: the generic EQ-5D and SF-36 for HRQoL, the specific Numerical Rating Scale (NRS) to measure pain intensity, and Oswestry Disability Index (ODI) to measure functional disability. We conducted multilevel regression analyses to investigate the association of HRQoL with the NRS and ODI indexes; multiple regression analyses to compare EQ-5D data with those of the general population adjusted for age, sex and education, and statistical tests to compare the changes of HRQoL, NRS and ODI estimates at baseline with those measured during the follow-up. RESULTS: Eighty patients (40% male, mean age = 58 years) participated. HRQoL was significantly worse in the patients than in the corresponding general population. Pain, functional disability and HRQoL significantly related each other during follow-up, Significant improvements (p < 0.001) in pain intensity, functional capability and HRQoL were reached after 6 months from SCS and generally remained stable during follow-up. Specific instruments provided detailed information on disability and pain, while generic instruments assessed the overall HRQoL and allowed a comparison with the general population's one. CONCLUSIONS: SCS + CMM treatment reaches a statistically significant and probably a clinically relevant improvement in pain perception, functional disability and HRQoL in patients with FBSS refractory to CMM. An appropriate selection of instruments for use in clinical practice is crucial for a routine assessment of health perception in patients, aimed to guide decisions for optimal treatment.

Cost-Effectiveness and Cost-Utility Analysis of Spinal Cord Stimulation in Patients With Failed Back Surgery Syndrome: Results From the PRECISE Study.

OBJECTIVE: To assess the cost-effectiveness and cost-utility of Spinal Cord Stimulation (SCS) in patients with failed back surgery syndrome (FBSS) refractory to conventional medical management (CMM). MATERIALS AND METHODS: We conducted an observational, multicenter, longitudinal ambispective study, where patients with predominant leg pain refractory to CMM expecting to receive SCS+CMM were recruited in 9 Italian centers and followed up to 24 months after SCS. We collected data on clinical status (pain intensity, disability), Health-Related Quality-of-Life (HRQoL) and on direct and indirect costs before (pre-SCS) and after (post-SCS) the SCS intervention. Costs were quantified in € 2009, adopting the National Health Service's (NHS), patient and societal perspectives. Benefits and costs pre-SCS versus post-SCS were compared to estimate the incremental cost-effectiveness and cost utility ratios. RESULTS: 80 patients (40% male, mean age 58 years) were recruited. Between baseline and 24 months post-SCS, clinical outcomes and HRQoL significantly improved. The EQ-5D utility index increased from 0.421 to 0.630 (p < 0.0001). Statistically significant improvement was first observed six months post-SCS. Societal costs increased from €6600 (pre-SCS) to €13,200 (post-SCS) per patient per year. Accordingly, the cost-utility acceptability curve suggested that if decision makers' willingness to pay per Quality-Adjusted-Life-Years (QALYs) was €60,000, SCS implantation would be cost-effective in 80% and 85% of cases, according to the NHS's and societal point of views, respectively. CONCLUSIONS: Our results suggest that in clinical practice, SCS+CMM treatment of FBSS patients refractory to CMM provides good value for money. Further research is encouraged in the form of larger, long-term studies.

The use of electrical source imaging in targeting lesional mesial temporal epilepsy for radiosurgical treatment.

Gamma knife radiosurgery (GK-RS) is a technique applied in selected cases of mesial-temporal epilepsy, although still limited to centres with adequate instrumentation and expertise. Here, we report a case of radio surgery targeted with the aid of electrical source imaging that localizes the cortical area generating the scalp epileptic discharges. The patient, a 39-year-old male, presented with a right mesio-temporal lesion; electrical source imaging localization partially overlapped with the lesional area but showed an important activation of the omolateral frontal area, concordant with the epileptic network. The patient underwent GK-RS, with good neurosurgical and clinical results. A radiosurgical ellipsoidal treatment volume area of 2 × 2 × 2 cm³, located over the right temporo-mesial region within a centre showing abnormal signal intensity, was considered. Seven months after treatment, the patient developed brain oedema that gradually resolved after one year. After three years of follow-up, the patient was seizure-free (Engel class I). Our very preliminary experience suggests that electrical source imaging appears to be a useful supporting tool for the definition of the radiosurgical treatment volume in selected patients with temporo-mesial lesional epilepsy.

Long-term quality of life and functional outcomes in adults surgically treated for intramedullary spinal cord tumor.

Introduction: Intramedullary spinal cord tumors (IMSCTs) are rare but clinically significant entities that may cause severe neurological decline with progressive pain and motor or sensory deterioration. Beyond the beneficial effects of surgical treatment and the long-term progression-free survival, neurological deficits may still persist after surgery, and information about the long-term patients' health-related quality of life (QoL) is still lacking. In this study, we investigate the patients' health perception 15 years after the surgery in an overall patients' wellbeing framework. Methods: Patients surgically treated for IMSCT over a period from 1996 to 2011 were selected. After a mean of 15 years from the surgery, patient's self-administered questionnaire on disability, pain, sleep quality, and QoL was collected and neurological postoperative evaluation at the chronic stage was reexamined. Results: Neurological deficits are reported in half of the patients in the postoperative chronic phase. After 15 years of surgery, half of the patients still report mild or severe disability grades associated with significantly higher pain and poor sleep and QoL. In accordance, the neurological condition measured at the chronic stage is significantly related not only to disease-specific symptoms (i.e., pain) but even to sleep quality complaints and poor QoL, measured at 15 years follow-up. Conclusions: Health-related QoL is an important secondary outcome in patients. Although the progression-free survival, worse postoperative neurological conditions could predict long-term sequelae reflecting patients' poor health perception. It suggests the importance of preserving patients' functional status and globally evaluating patients' wellbeing to handle disease-specific symptoms but even more general aspects of QoL.

Percutaneous balloon compression for the treatment of trigeminal neuralgia in patients with multiple sclerosis. Analysis of the potentially prognostic factors.

BACKGROUND: The role of different procedures for the treatment of drug-resistant trigeminal neuralgia (TN) in patients affected by multiple sclerosis (MS) is under discussion and there are no clear indications in the literature. In particular, the role of percutaneous balloon compression (PBC) has been poorly addressed so far. Moreover, to the best of our knowledge, there are no reports analysing the factors potentially related to the prognosis in these patients. We examined the role of PBC for the treatment of TN in MS patients and investigated the role of some clinical and procedure-related factors in determining the prognosis of these patients. METHOD: We retrospectively reviewed clinical and outcome data of 21 MS patients submitted to PBC (eight of them had already been treated with different procedures). We analysed the impact of the sex, number of affected trigeminal divisions, pre-operative deficit, previous operations, compression time and balloon shape at the operation, on acute pain relief (APR) by the chi-squared statistic and on pain-free survival (PFS) by the Kaplan-Meier method. FINDINGS: An excellent (BNI I-II)-good (BNI III) outcome was obtained in all patients with a single or repeated procedure. The presence of a single affected trigeminal division (p = 0.042), the absence of previous operations (p = 0.048), the compression time ≤5 min (p = 0.0067) and the pear-like shape of the balloon at the operation (p < 0.05) were associated to higher pain-free survival. CONCLUSIONS: PBC is a safe and effective technique to treat drug-resistant TN in MS patients. Some clinical and procedure-related factors may play a role in the prognosis of these patients.

Vagus nerve stimulation in drug-resistant epilepsies. Analysis of potential prognostic factors in a cohort of patients with long-term follow-up.

BACKGROUND: The results of vagus nerve stimulation (VNS) for the treatment of drug-resistant epilepsies are highly variable due to the lack of defined patient's selection criteria and a follow-up of published studies being generally too short. Here we report the outcome of VNS in a series with long-term follow-up and try to identify subgroups of patients who could be better candidates for this procedure. METHOD: We studied 53 patients (33 male, 20 female) with a prospectively recorded follow-up (mean, 55.96 ± 43.53 months). The monthly average seizure frequency for each patient at baseline, 3, 6, 12 months, and each year until the latest follow-up after implant was measured and the percentage of "responders" and response time (RT) were calculated. We investigated the following potential prognostic role of these factors: age of onset of epilepsy, pre-implant epilepsy duration, etiology, and age at implant. RESULTS: Globally, 40 % of patients responded to VNS (mean RT, 14.85 ± 16.85 months). Lesional etiology (p = 0.0179, logrank test), particularly ischemia (p = 0.011, Fisher exact test) and tuberous sclerosis (p = 0.0229, Fisher exact test), and age at implant <18 years (p = 0.0242, logrank test) were associated to better response to VNS. In the lesional subgroup the best results were observed in patients with a pre-implant epilepsy duration <15 years (p = 0.0204, logrank test) and an age at implant <18 years (p = 0.0187 logrank test). CONCLUSIONS: The best candidate to VNS seems to be a patient with lesional etiology epilepsy (particularly post-ischemic and tuberous sclerosis) and a short duration of epilepsy who undergo VNS younger than 18 years.

Surgery for intramedullary spinal cord ependymomas in the neuromonitoring era: results from a consecutive series of 100 patients.

OBJECTIVE: The established treatment of intramedullary spinal cord ependymomas (ISCEs) is resection. Surgical series reporting treatment results often lack homogeneity, as these are collected over long time spans and their analysis is plagued by surgical learning curves and inconsistent use of intraoperative neurophysiological monitoring (IONM). The authors report the oncological and functional long-term outcomes in a modern series of 100 consecutive ISCEs that were resected between 2000 and 2015 by a surgically experienced team that consistently utilized IONM. METHODS: In this retrospective study, the authors tailored surgical strategy and multimodal IONM, including somatosensory evoked potentials, muscle motor evoked potentials (mMEPs), and D-waves, with the aim of gross-total resection (GTR). Preservation of the D-wave was the primary objective, and preservation of mMEPs was the second functional objective. Functional status was evaluated using the modified McCormick Scale (MMS) preoperatively, postoperatively, and at follow-up. RESULTS: Preoperatively, 89 patients were functionally independent (MMS grade I or II). A GTR was achieved in 89 patients, 10 patients had a stable residual, and 1 patient underwent reoperation for tumor progression. At a mean follow-up of 65.4 months, 82 patients were functionally independent, and 11 lost their functional independence after surgery (MMS grades III-V). Muscle MEP loss predicted short-term postoperative worsening (p < 0.0001) only, while the strongest predictors of a good functional long-term outcome were lower preoperative MMS grades (p < 0.0001) and D-wave preservation. D-wave monitorability was 67%; it was higher with lower preoperative MMS grades and predicted a better recovery (p = 0.01). CONCLUSIONS: In this large series of ISCEs, a high rate of GTR and long-term favorable functional outcome were achieved. Short- and long-term functional outcomes were best reflected by mMEPs and D-wave monitoring, respectively.

Vertebroplasty for symptomatic monostotic Paget disease.

Paget disease (PD) is a chronic metabolically active bone disorder. The spine is the second most commonly involved site; the pathologic changes can cause back pain, myeloradiculopathy, and vertebral fracture. Symptomatic patients are treated medically, and surgery is required when certain complications occur. A case is presented of monostotic vertebral PD treated by percutaneous vertebroplasty (PV) with successful outcome characterized by pain relief and improved disability at 6-month follow-up. PV is proposed as a primary treatment for back pain secondary to PD when unresponsive to conservative therapy and when not associated with other complications.

Craniotomy repair with the retrosigmoid approach: the impact on quality of life of meticulous reconstruction of anatomical layers.

INTRODUCTION: Various cranial repairs have been described to limit the incidence of cerebrospinal fluid (CSF) leak, the rate of infections, postoperative headache and local discomfort in patients undergoing cerebello-pontine angle surgery. MATERIALS AND METHODS: The aim of this study was to evaluate the impact of a feasible craniotomy procedure and cranial repair technique, which does not require bone replacers or filling materials, on postoperative outcome. We analysed postoperative results in a series of 34 patients undergoing cerebello-pontine angle surgery. DISCUSSION AND CONCLUSIONS: We observed a statistically significant reduced incidence of local discomfort, postoperative headache and CSF leak in patients who underwent such a reconstructive technique compared to those undergoing retrosigmoid craniectomy.

Vagal nerve stimulation for drug-resistant epilepsies in different age, aetiology and duration.

PURPOSE: The aim of the study was to compare the outcome with respect to age of implant, aetiology and duration of epilepsy. METHODS: One hundred thirty-five drug-resistant epileptic patients, excluded from ablative surgery, were submitted to vagal nerve stimulation (1995-2007). Aetiology was cryptogenic in 57 and symptomatic in 78 patients. Ages of implant were 0.5-6 years (18 patients), 7-12 years (32 patients), 13-18 years (31 patients) and more than 18 years (54 patients). Epilepsy types were Lennox-Gastaut (18 patients), severe multifocal epilepsy (33 patients) and partial (84 patients). Duration of epilepsy is 3 months to 57 years. Clinical outcome was determined by comparing the seizure frequency after stimulation at 3-6-12-18-24-36 months with the previous 3 months. 'Responders' were the patients experiencing a seizure frequency reduction of 50% or more during follow-up. In statistical analysis, Wilcoxon and McNemar tests, general linear model for repeated measures, logistic regression and survival analysis were used. RESULTS: The seizure frequency reduction was significant in the group as a whole between baseline and the first follow-up (Wilcoxon test). The percentage of responder increases with time (McNemar test p = 0.04). Univariate analysis showed a significant effect of the age of implant on seizure frequency reduction: Adult patient had worst clinical outcome than children (p < 0.001) and adolescents (p = 0.08). Patients with severe multifocal epilepsy had better percentage seizure reduction compared with Lennox-Gastaut and partial (p = 0.03). Lesser duration of epilepsy had positive influence on outcome. Multivariate analysis confirmed age of implant to be the strongest factor influencing prognosis. Furthermore, positive is the association between lesional aetiology and young age. CONCLUSIONS: The best responder could be a young lesional epileptic patient; after 3 years of follow-up, the percentage of responders is still in progress.

High frequency extradural motor cortex stimulation transiently improves axial symptoms in a patient with Parkinson's disease.

In a primate model of Parkinson's disease (PD), the benefit of extradural motor cortex stimulation (EMCS) was associated with high-frequency stimulation (130 Hz), whereas no significant motor improvement was achieved at 10 Hz or intermediate frequencies of stimulation. We report the case of a 72-year-old female patient affected by severe PD who underwent bilateral EMCS. In baseline med-off condition the patient was unable to arise from a chair and to stand without assistance. Stimulation at 3 and 60 Hz failed to provide any improvement of symptoms, whereas, when stimulating at 130 Hz, axial akinesia and walking improved consistently: the patient, in med-off condition, was able to arise from chair and to walk without assistance. The patient underwent two brain 99mTc- Ethylcysteinate Dimer-SPECT studies: semiquantitative and Statistical Parametric Mapping revealed that the regional cerebral perfusion was significantly increased in the supplementary motor area during stimulation at 130 Hz. After five months, the benefit of EMCS gradually disappeared.

Surgical Management of Anterolateral and Posteromedial Incisural Tentorial Meningioma.

BACKGROUND: Tentorial meningiomas are a broad and consistent category of tumors but their definition is still unclear and their classification uncertain. OBJECTIVE: To report the clinical and surgical characteristics of tentorial hiatus meningiomas based on a revised classification of tentorial meningiomas. METHODS: We reviewed the records of 14 patients who had undergone microsurgical removal of incisural tentorial meningioma. Two tumor subgroups, anterolateral (AL) and posteromedial (PM), were distinguished according to their site of attachment: the middle third and the posterior third of the tentorial free margin, respectively. Clinical presentation, radiological findings, surgical approaches, extent of resection, and outcome were compared. RESULTS: The 2 subgroups differed by tumor size (larger in PM), incidence of the direction of growth (infratentorial in PM), and hydrocephalus (only in PM), as well as by some clinical aspects. Surgical approach depended on tumor location: lateral (pterional, subtemporal, and retromastoid) for AL lesions; medial (occipital or supracerebellar infratentorial) for PM lesions. Total removal (Simpson grade I-II) was performed in 64% of cases and complications occurred in 14%. Stereotactic radiosurgery was performed in cases of incomplete resection. At a mean follow-up of 104.5 mo, clinical improvement with low recurrence (9%) was achieved. CONCLUSION: Reallocation of tentorial edge meningiomas is the premise to compare treatment and further improve the approach case-by-case. In spite of their deep site, good outcomes can be achieved in both AL and PM tentorial meningiomas. Also of note is the indolent behavior of residual tumor.

Effect of vagal nerve stimulation on systemic inflammation and cardiac autonomic function in patients with refractory epilepsy.

OBJECTIVE: Recent data suggest that vagus nerve stimulation (VNS) can inhibit cytokine release by inflammatory cells. Accordingly, an association between impaired cardiac parasympathetic function, as assessed by heart rate variability (HRV), and increased markers of inflammation has recently been reported. In this study we assessed the effect of direct left VNS on inflammatory markers and HRV in patients with refractory epilepsy. METHODS: A 24-hour electrocardiogram Holter recording was performed both at baseline and after 3 months of left VNS in 8 patients (age 32 +/- 24 years, 2 men) who underwent implantation of a VNS device because of refractory epilepsy. Tumor necrosis factor-alpha, interleukin-6 and C-reactive protein serum levels were measured, as markers of inflammation, at the same times. RESULTS: No significant changes were found after 3 months of left VNS, compared to baseline, both for HRV variables and inflammatory markers. Also, no consistent correlation could be demonstrated between HRV parameters and inflammatory markers in these patients. CONCLUSIONS: Our data in epileptic patients without cardiovascular disease failed to show a significant effect of left VNS on cardiac autonomic function and on systemic inflammation at short-term follow-up.

Next-generation repeat-free FISH probes for DNA amplification in glioblastoma in vivo: Improving patient selection to MDM2-targeted inhibitors.

A next-generation FISH probe mapping to the MDM2 locus-specific region has recently been designed. The level of MDM2 gene amplification (high versus low) may allow selection of patients for cancer treatment with MDM2 inhibitors and may predict their responsiveness. We investigated the spectrum of MDM2 gene alterations using the new probes in vivo after visualizing single neoplastic cells in situ from a series of glioblastomas. Signals from next-generation repeat-free FISH interphase probes were identified in tissue microarrays that included 3 spots for each of the 48 cases. The murine double minutes (MDM2)-specific DNA probe and the satellite enumeration probe for chromosome 12 were used. Three cases (6%) showed more than 25 signals (high gene amplification), and 7 (15%) showed 3-10 signals (gains); among these, 4 cases (8%) had an equal number of MDM2 and centromeric signals on chromosome 12 (polyploidy). Genomic heterogeneity was observed only in 3 cases with low gene amplification. In our series, 6% of glioblastomas exhibited high MDM2 amplification (in vivo) with a pattern related to the known double minutes/chromothripsis phenomenon (in situ), and only cases with low amplification showed genomic heterogeneity. We concluded that the rate of MDM2 gene amplification can be a useful predictive biomarker to improve patient selection.

Direct demonstration that repetitive transcranial magnetic stimulation can enhance corticospinal excitability in stroke.

BACKGROUND AND PURPOSE: Preliminary studies suggest that electrical stimulation of the damaged cortex may be able to enhance motor recovery after stroke. The hypothesis has been that this increases cortical excitability, making it easier for the system to respond to and learn from conventional physiotherapy. However, there is no direct evidence that the cortex of patients with stroke can respond in this fashion; hence, the basis of these new approaches has been questioned. METHODS: We had the opportunity to evaluate directly the effects of noninvasive cortical stimulation on the excitability of corticospinal output from the damaged hemisphere of a chronic stroke patient who had epidural electrodes implanted in the upper dorsal cord for treatment of pain. RESULTS: We found that it was possible to enhance corticospinal activity evoked by single test stimuli. CONCLUSIONS: This study confirms directly that it is possible to noninvasively manipulate cortical excitability in stroke.

Anterior cervical discectomy and interbody fusion with porous tantalum implant. Results in a series with long-term follow-up.

Few papers have been published about the anterior cervical discectomy and fusion (ACDF) with implant of porous tantalum cages. These studies included patients submitted to operation at a single level. To our knowledge, we report the results of the largest series of ACDF with implant of porous tantalum cages. Our series included patients operated at a single or double level with a long follow-up (FU). We also discuss the pertinent literature. Clinical and outcome data of 99 consecutive patients (47 men, 52 women) submitted to ACDF with implant of porous tantalum cages (Trabecular Metal TM-S Cervical Fusion Device, Zimmer Spine, Minneapolis, MN) from June 2007 to September 2012, were retrospectively reviewed. Mean FU was 67.47±19.63months. The changes in pain were assessed using the Visual Analogue Scale (VAS). Patients were evaluated pre-operatively and at FU with the Short Form-36 Score Health Survey Version 2.0 (SF-36v2) for Physical Health and Mental Health Scores and the Neck Disability Index. We globally found a statistically significant improvement of all evaluated scores. Patients operated at two levels experienced a statistically significant improvement of all scores, with no statistical difference compared to patients operated at one level. No major complications occurred post-operatively and at FU. Only one patient (operated at two level) experienced an infection during FU. We conclude that ACDF with porous tantalum cages is a safe procedure, with long term clinical benefits (also in patients operated at two levels) and a very low rate of complications.

Recurrent Atypical Meningiomas: Combining Surgery and Radiosurgery in One Effective Multimodal Treatment.

OBJECTIVE: Owing to their rarity and proteiform pathologic features, the clinical behavior of atypical meningiomas is not yet well characterized. Though the extent of resection is believed to be a key determinant of prognosis, limited data exist regarding optimal management of patients with recurrent disease. METHODS: In this 20-year retrospective case series, we reviewed the medical records of 46 patients with recurrent atypical meningiomas (185 lesions, 89 of which were local, 78 marginal, and 18 distant recurrences); treatment was radiosurgery (n = 60), surgery (n = 56), or both (n = 8). The median follow-up period was 53 months. Outcome measures were length of overall survival and disease-free intervals and prognostic factors for survival. RESULTS: Overall, the median progression-free survival was 26 months at the first recurrence and 100 months thereafter (the sum of the later intervals). Multivariate analysis showed that no treatment-related factors influenced prognosis, whereas recurrence at the skull base was a significant tumor-related factor limiting further treatment. Irrespective of treatment type, the recurrence-free interval was increasingly shorter during the clinical course, with a higher occurrence of marginal and distant lesions migrating to the midline and to the skull base. In sporadic cases, disease-free intervals were longer after wide craniotomy, tumor and dural resection with tumor-free margin. CONCLUSIONS: The disease-free interval was substantially similar after surgery and radiosurgery for treating recurrent disease in patients with atypical meningiomas. Surgery is the mainstay for prolonging survival, while radiosurgery can be an adjuvant strategy to gain time for clinical observation and planning aggressive surgical treatment.

Primary intramedullary neurocytoma: Case report and literature analysis.

BACKGROUND: Primary intramedullary neurocytoma is extremely rare. Due to its rarity, it is difficult to collect a wide series in a single institution to perform a survival analysis and give indications about prognosis and treatment. CASE DESCRIPTION: Here, we report on a case of a 37-year-old woman with primary intramedullary neurocytoma and perform a systematic statistical analysis of cases reported in the literature. Of 21 articles found, 15 studies and the present case (22 patients) were eligible for the analysis. We studied the impact of age, sex, number of involved levels (≤2 vs. >2), entity of resection, postoperative radiotherapy (RT), proliferation index (Ki67) on the neurological outcome of patients, and on the recurrence of the tumor. Comparison of categorical variables was performed by the χ (2) statistic. The Kaplan-Meier curves were plotted to calculate the progression-free survival (PFS) of these patients. P < 0.05 was considered as statistically significant. The 1-year PFS was 95.45% and the 2-year PFS was 86.36%. A gross total resection was associated to a worsening of the neurological function with no impact on the tumor recurrence. Adjuvant RT significantly improved the neurological function. A lower Ki67 was strongly associated with a lower tumor recurrence. CONCLUSIONS: We think that the goal of the surgery should be to preserve a good neurological function even if a residual tumor has to be left. Ki67 should be always evaluated due to its impact on the prognosis. Although adjuvant RT significantly improved the neurological function, its role in preventing the tumor recurrence is not clearly defined.

Advances in diagnosis and treatment of trigeminal neuralgia.

Various drugs and surgical procedures have been utilized for the treatment of trigeminal neuralgia (TN). Despite numerous available approaches, the results are not completely satisfying. The need for more contemporaneous drugs to control the pain attacks is a common experience. Moreover, a number of patients become drug resistant, needing a surgical procedure to treat the neuralgia. Nonetheless, pain recurrence after one or more surgical operations is also frequently seen. These facts reflect the lack of the precise understanding of the TN pathogenesis. Classically, it has been related to a neurovascular compression at the trigeminal nerve root entry-zone in the prepontine cistern. However, it has been evidenced that in the pain onset and recurrence, various neurophysiological mechanisms other than the neurovascular conflict are involved. Recently, the introduction of new magnetic resonance techniques, such as voxel-based morphometry, diffusion tensor imaging, three-dimensional time-of-flight magnetic resonance angiography, and fluid attenuated inversion recovery sequences, has provided new insight about the TN pathogenesis. Some of these new sequences have also been used to better preoperatively evidence the neurovascular conflict in the surgical planning of microvascular decompression. Moreover, the endoscopy (during microvascular decompression) and the intraoperative computed tomography with integrated neuronavigation (during percutaneous procedures) have been recently introduced in the challenging cases. In the last few years, efforts have been made in order to better define the optimal target when performing the gamma knife radiosurgery. Moreover, some authors have also evidenced that neurostimulation might represent an opportunity in TN refractory to other surgical treatments. The aim of this work was to review the recent literature about the pathogenesis, diagnosis, and medical and surgical treatments, and discuss the significant advances in all these fields.

Leksell Gamma Knife for pediatric and adolescent cerebral arteriovenous malformations: results of 100 cases followed up for at least 36 months.

OBJECT: The goal of this study was to evaluate advantages, risks, and failures of Gamma Knife radiosurgery (GKRS) in a large series of pediatric and adolescent patients with cerebral arteriovenous malformations (cAVMs) who were followed up for at least 36 months. METHODS: Since February 1993, 100 pediatric and adolescent patients (≤ 18 years of age) with cAVMs have undergone GKRS at the authors' institution and were followed up for at least 36 months. Forty-six patients were boys and 54 were girls; the mean age was 12.8 years (range 3-18 years). Hemorrhage, either alone or combined with seizure, was the clinical onset in 70% of cases. The mean pre-GK cAVM volume was 2.8 ml; 92% of cAVMs were Spetzler-Martin (S-M) Grades I-III. Most lesions (94%) were in eloquent or deep-seated brain regions, according to S-M classification. The parameters for mean and range in treatment planning were prescription isodose 53.8% (40%-90%); prescription dose (PD) 20.2 Gy (9.0-26.4 Gy); maximal dose (MD) 37.8 Gy (18-50 Gy); and number of shots 4.7 (1-17). On the day of GKRS, stereotactic CT or stereotactic MRI and digital subtraction angiography were used. RESULTS: Obliteration rate (OR) was angiographically documented in 75 of 84 cases (89.3%) after single-session GKRS, with actuarial ORs at 3 and 5 years of 68.0% and 88.1%, respectively. A repeat treatment was performed in 7 patients (6 with obliteration), and 16 patients with cAVMs underwent staged treatment (9 of them were angiographically cured). Thus, the overall OR was 90%, with actuarial ORs at 3, 5, and 8 years of 59.0%, 76.0%, and 85.0%, respectively. Permanent symptomatic GK-related complications were observed in 11% of cases, with surgical removal of enlarged mass seen on post-RS imaging needed in 5 cases. Hemorrhage during the latency period occurred in 9% of patients, but surgical evacuation of the hematoma was required in only 1 patient. One patient died due to rebleeding of a brainstem cAVM. Radiosurgery outcomes varied according to cAVM sizes and doses: volumes ≤ 10 ml and PDs > 16 Gy were significantly associated with higher ORs and lower rates of permanent complication and bleeding during the latency period. CONCLUSIONS: The data from this study reinforce the conclusion that GKRS is a safe and effective treatment for pediatric and adolescent cAVMs, yielding a high OR with minimal permanent severe morbidity and no mortality. The very low frequency of severe hemorrhages during the latency period further encourages a widespread application of RS in such patients. Univariate analysis found that modified RS-based cAVM score, nidus volume, PD, integral dose, S-M grade, and preplanned treatment (the last 2 parameters were also confirmed on multivariate analysis) significantly influenced OR. Lower S-M grades and single-session planned treatments correlated with shorter treatment obliteration interval on univariate analysis. This statistical analysis suggests that a staged radiosurgical treatment should be planned when nidus volume > 10 ml and/or when the recommended PD is ≤ 16 Gy.