Deep brain stimulation of anterior nucleus and centromedian nucleus of thalamus in treatment for drug-resistant epilepsy.

INTRODUCTION: Drug-resistant epilepsy (DRE) remains poorly-controlled in c.33% of patients, and up to 50% of patients suffering from DRE are deemed not to be suitable candidates for resective surgery. For these patients, deep brain stimulation (DBS) may constitute the last resort in the treatment of DRE. STATE OF THE ART: We undertook a systematic review of the current literature on DBS efficacy and the safety of two thalamic nuclei-anterior nucleus of the thalamus (ANT) and the centromedian nucleus of the thalamus in the management of patients with DRE. A search using two electronic databases, the Medical Literature, Analysis, and Retrieval System on-line (MEDLINE) and the Cochrane Central Register of Controlled Trials (CEN-TRAL) was conducted. CLINICAL IMPLICATIONS: We found 30 articles related to ANT DBS and 13 articles related to CMN DBS which were further analysed. Based on the clinical research articles, we found a mean seizure frequency reduction for both thalamic nuclei. For ANT DBS, the mean seizure frequency reduction ranged from 48% to 75%, and for CMN DBS from 46.7% to 91%. The responder rate (defined as at least 50% reduction in seizure frequency) was reported to be 53.2-75% for patients after ANT DBS and 50-90% for patients after CMN DBS. FUTURE DIRECTIONS: ANT and CMN DBS appear to be safe and efficacious treatments, particularly in patients with refractory partial seizures and primary generalised seizures. ANT DBS reduces most effectively seizures originating in the temporal and frontal lobes. CMN DBS reduces mostly primary generalised tonic-clonic and atypical absences and atonic seizures. Seizures related to Lennox-Gastaut syndrome respond very favourably to CMN DBS.

The ventral capsule and ventral striatum-Stereotactic targets for the management of treatment-resistant depression. A systematic literature review.

Background: Deep brain stimulation (DBS) is still an experimental treatment modality for psychiatric disorders including treatment-resistant depression (TRD). There is preliminary evidence that stimulation of brain reward circuit structures including the ventral striatum (VS) may exert an antidepressant effect. The main nucleus of the reward circuit is the nucleus accumbens (NAc). The NAc is a major structure of VS that plays a critical role in reward-seeking behavior, motivation, and addiction. Aims: This study aimed to review the current studies including randomized clinical trials, open-label trials, and case reports of NAc/VS and VC DBS for TRD in humans. Method: The literature was reviewed using a medical database-Medical Literature, Analysis, and Retrieval System Online (MEDLINE) on NAc/VS or VC DBS in TRD. The identified studies were assessed based on the patient's characteristics, clinical outcomes, and adverse events related to DBS as well as the stereotactic technique used to guide the implantation of DBS electrodes. The inclusion and exclusion criteria of DBS for TRD were presented and discussed. Results: The searched literature revealed one case report, three open-label studies (OLS), one multicenter open-label study (mOLS), and two randomized clinical trials (RCTs). There were three additional studies reporting the clinical outcomes in the long term in TRD patients included in the two mentioned RCTs. The total number of patients with TRD treated by NAc/VS or VC is estimated to be 85 individuals worldwide. The response rate to DBS defined as a 50% reduction of postoperative Montgomery-Asberg Depression Rating Scale (MADRS) scores was achieved in 39.8% of the operated patients (range, 23-53%). The remission defined as MADRS scores of < 10 was found in 17.8% after DBS (range, 0-40%). The mean follow-up was 19.7 months (range 3.7-24 months). Conclusion: The current results of NAc/VS and VC DBS are still limited by a relatively small number of patients treated worldwide. Nevertheless, the results suggest that NAc/VS and VC can be regarded as promising and efficacious targets for DBS, taking into account the response and remission rates among TRD patients with no other treatment option. The adverse events of NAc/VS and VC DBS are reversible due to the adjustment of stimulation parameters. The most common adverse events were hypomanic/manic states, suicidal thoughts/attempts, and suicides. Patients with TRD after NAc/VS and VC DBS should be strictly followed to prevent or diminish these stimulation-induced adverse events.

Spinal cord stimulation for treatment of complex regional pain syndrome: a single-centre retrospective case series study.

INTRODUCTION: Complex regional pain syndrome (CRPS) is a debilitating disease with limited available treatment options. Spinal cord stimulation (SCS) is a universal option that promises to improve quality of life by reducing intractable neuropathic pain. The aim of this study was to describe the effectiveness and safety of SCS as a treatment for CRPS patients. CLINICAL RATIONALE FOR THE STUDY: SCS as an invasive method has relatively recently been introduced to CRPS therapy. We hypothesised that by assessing the effectiveness and safety of SCS, we could justify its early use in the treatment of this debilitating condition. MATERIAL AND METHODS: CRPS is a multifactorial and disabling disorder with complex aetiopathogenesis. The primary goals of CRPS treatment include pain relief, functional restoration, and psychological stabilisation. Early intervention is needed to achieve these objectives. In this study, we performed a retrospective evaluation of clinical outcomes in seven patients with severe, intractable CRPS treated by SCS. All patients underwent implantation of a non-rechargeable prime advanced MRI implantable pulse generator (IPG) (Medtronic, Minneapolis, MN, USA) between December 2017 and December 2020 using identical surgical and intraprocedural techniques. RESULTS: From a total of 21 patients treated with SCS over the three years in question, seven (33%) were diagnosed with severe CRPS. The duration of chronic pain ranged between two and 12 years. In six cases (86%), an electrode was implanted in the thoracic segment. Good (partial pain reduction) or very good (complete pain relief) treatment results were observed in five patients (72%). In two cases (28%), two revision surgeries were performed for wound debridement. These hardware-related complications were primarily related to erosions located over implanted IPG's. CONCLUSIONS AND CLINICAL IMPLICATIONS: SCS is the best alternative for patients with CRPS. It should be used immediately after the failure of conservative treatment. Despite the relatively high complication rate in our series, it is the best choice for pain reduction management in this select group of patients.

Subcallosal Cingulate Cortex Deep Brain Stimulation for Treatment-Resistant Depression: A Systematic Review.

Background: Deep brain stimulation (DBS) is considered a relatively new and still experimental therapeutic modality for treatment-resistant depression (TRD). There is clinical evidence to suggest that stimulation of the subcallosal cingulate cortex (SCC) involved in the pathogenesis of TRD may exert an antidepressant effect. Aims: To conduct a systematic review of current studies, such as randomized clinical trials (RCTs), open-label trials, and placebo-controlled trials, examining SCC DBS for TRD in human participants. Method: A formal review of the academic literature was performed using the Medical Literature, Analysis, and Retrieval System Online (MEDLINE) and Cochrane Central Register of Controlled Trials (CENTRAL) databases. This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Suitable studies were screened and assessed based on patient characteristics, clinical outcomes, adverse events related to DBS, and the stereotactic technique used to guide the implantation of DBS electrodes. Results: The literature search identified 14 clinical studies that enrolled a total of 230 patients with TRD who underwent SCC DBS. The average duration of follow-up was 14 months (range 6-24 months). The response and remission rates at the last available follow-up visit ranged between 23-92% and 27-66.7%, respectively. Conclusion: The current results of SCC DBS are limited by the relatively small number of patients treated worldwide. Nevertheless, studies to date suggest that SCC can be a promising and efficacious target for DBS, considering the high response and remission rates among patients with TRD. The adverse events of SCC DBS are usually transient and stimulation-induced.

Significant epidural electrode migration out of the spinal canal due to prolonged latent infection of the spinal cord stimulation hardware.

Electrode migration is one of the most common complication of Spinal Cord Stimulation (SCS). Usually the lead migrates cranio-caudally or laterally and in the vast majority of cases occurs during the first few months after implantation. One method of preventing lead migration is the use of open-surgical insertion of paddle electrodes. A CASE REPORT: 51-year old woman was admitted for a revision of postoperative wound after implantation of Spinal Cord Stimulator, which was inserted 4 years earlier due to Failed Back Surgery Syndrome (FBSS). Two years after surgery the patient reported severe pain at the site of electrode implantation. After removal of scar tissue pulling on electrode wires the symptoms subsided. In the following months impaired healing of the postoperative wound was observed. For a long time, the patient would not consent to removal of SCS hardware because of good therapeutic effect. When she was finally admitted for surgery, radiological examination demonstrated significant electrode migration out of the vertebral canal. Surgery was performed to remove all of the hardware. CONCLUSIONS: In this case, electrode migration out of the vertebral canal resulted from prolonged infection of SCS hardware. The importance of an infection prevention in neuromodulation procedures should be highlighted. According to our best knowledge, this is the first presented case of paddle type electrode extraspinal migration.

Subjective and Objective Quality-of-Life Assessment of Outcome Measures in Cervical Spine Surgery for Degenerative Changes.

Cervical spine diskectomy is a commonly used procedure in degenerative disease of cervical spine surgery. However, it is difficult to assess the quality of life after this widely applied and variously modified procedure. This literature review presents cervical diskectomy results, according to various scales and measures in multidirectional surgical strategies. Using relevant databases, we tried to find the best treatment options for degenerative disk disease and the best method of quality-of-life assessment, searching for modalities that may influence the outcome.

Usefulness of the FOUR scale to assess the state of consciousness of the patients treated in the Intensive Care Unit.

The Glasgow Coma Scale (GCS) is a widely adopted clinical scale which fails to assess a verbal component in intensive care units (ICUs) patients who are ventilated mechanically. AIM: The aim of the study was to evaluate the validity of the FOUR scale (Full Outline of UnResponsivness) when applied by staff of an ICU. MATERIALS AND METHODS: This prospective cohort study included 65 consecutive intubated patients treated in the ICU with brain damage. The study design included the simultaneous assessment of the patients' consciousness by two scales - the FOUR scale and the GCS. All assessments were made under strict inclusion and exclusion criteria. The patients were assessed by a randomly selected staff pairs (neurointensivist/ nurse, neurointensivist/resident, neurointensivist/neurointensivists). The assessments made by experienced neurointensivists were regarded as basic examinations and by other members as control examinations. The study design allowed for the assessment of the interrater reliability. RESULTS: In 65 enrolled patients, a total of 763 double assessments were made using the FOUR score and by the GCS. It has been shown that in 751 out of 763 assessments the patients' consciousness was accurately assessed, representing 98.43 % accuracy of the FOUR scale. In contrast, the patients' consciousness was reliably assessed by the GCS in only 88 assessments, representing 11.5 % of accuracy. CONCLUSIONS: The study showed excellent interrater reliability among the groups of examiners for the FOUR scale as well as the GCS. The main advantage of the FOUR scale in intubated patients is excellent accuracy. The FOUR scale is easy to learn. It is functional and it has no limitations typical of verbal scales. It is a valuable and recommended clinical tool for the assessment of consciousness of the ICU patients.

Role of Diffusion Tensor Imaging Parameters in the Characterization and Differentiation of Infiltrating and Non-Infiltrating Spinal Cord Tumors : Preliminary Study.

BACKGROUND AND PURPOSE: Recent attempts to utilize diffusion tensor imaging (DTI) to identify the extent of microinfiltration of a tumor in the brain have been successful. It was therefore speculated that this technique could also be useful in the spinal cord. The aim of this study was to differentiate between infiltrating and noninfiltrating intramedullary spinal tumors using DTI-derived metrics. MATERIAL AND METHODS: The study group consisted of 6 patients with infiltrating and 12 with noninfiltrating spinal cord tumors. Conventional magnetic resonance imaging (MRI) with gadolinium administration was performed followed by DTI. Fractional anisotropy (FA), diffusivity (TRACE) and apparent diffusion coefficient (ADC) were measured in the enhancing tumor mass, peritumoral margins, peritumoral edema and normal appearing spinal cord. The results were compared using non-parametric Mann-Whitney U test with statistical significance p < 0.05. RESULTS: In peritumoral margins the FA values were significantly higher in the noninfiltrating compared to the infiltrating tumors (p < 0.007), whereas TRACE values were significantly lower (p < 0.017). The results were similar in peritumoral edema. The FA values in the tumor mass showed no significant differences between the two groups while TRACE showed a statistically significant difference (p < 0.003). There was no statistical difference in any parameters in normal appearing spinal cord. CONCLUSION: Quantitative analysis of DTI parameters of spinal cord tissue surroundings spinal masses can be useful for differentiation between infiltrating and non-infiltrating intramedullary spinal tumors.

Lateral approach for recurrent unilateral cervical radiculopathy after anterior discectomy with fusion. Report of two cases.

Recurrent radiculopathy after anterior cervical discectomy with fusion (ACDF) occurs in approximately 4% of cases. The main obstacles of revision surgery after ACDF via the same approach are scar tissue and arthrodesis. We present two patients with recurrent symptoms after ACDF who underwent revision surgery using an alternative, less invasive lateral approach (LA). These two patients both presented with recurrent unilateral cervical radiculopathy due to progression of intervertebral foraminal stenosis. The second patient also presented with paraparesis of the lower limbs and central stenosis. Anterior foraminotomy in the first case and oblique corpectomy in the second were performed via the LA. The previously implanted interbody cages were left intact and no new fusion procedures were needed. No spinal instability or symptom relapse was observed in follow-up. The lateral approach to the cervical spine enables direct and effective decompression of neural structures without violation of previously achieved interbody fusion.

Symptomatic medulla compression by vertebral artery.

OBJECTIVE: Vertebral artery medulla compression syndrome (VAMCS) is a very rare condition manifesting as different neurological focal deficits. The case of a 36-year-old male with symptomatic brainstem compression by vertebral artery (VA) treated by means of microvascular decompression (MVD) and a review of the literature is presented. CASE REPORT: On admission, a 36-year-old patient presented with hypoalgesia, hypothermesthesia and hemiparesis on the left side. Magnetic resonance imaging (MRI) of the head disclosed the right VA loop compressing the ventrolateral medulla and excluded other entities such as brain tumor, stroke and multiple sclerosis. Since displacement and significant compression of the right pyramidal tract was confirmed by diffusion tensor imaging (DTI), neurovascular compression syndrome was diagnosed. The patient underwent MVD of the medulla using a Gore-Tex implant as a separating material via the right far-lateral approach. The left hemiparesis and hemisensory loss remitted rapidly after the procedure. The post-procedural neurological improvement was maintained at one year follow-up. Based on a review of the literature, a total of 33 cases of surgically treated VAMCS has been reported so far. CONCLUSION: VAMCS should be considered as the cause of neurological deficits when other pathological entities are ruled out. In symptomatic conflict of the VA with the medulla, microvascular decompression using a Gore-Tex implant can be an effective method of treatment. Nevertheless, a statistical analysis on all reported cases showed favorable results using the VA repositioning technique when compared with MVD (success rate 91% vs. 58%, p<0.05).

Surgical treatment of intramedullary ependymomas.

OBJECT: The aims of this study were to present the results of surgery for intramedullary ependymomas (IEs), analyze complication and recurrence rates, and analyze factors that might influence outcome. METHODS: The charts of 29 consecutive patients (women - 8, men - 21; mean age - 38 years; range: 18-72) operated for IE were retrospectively analyzed. Mean follow-up was 9 years. Eighteen tumors (62%) were located in the cervical or cervicothoracic spine, and average tumor length was four spinal levels. Twenty patients (69%) presented with neurological deficit. RESULTS: Gross total resections (GTRs) comprised 87% of cases, subtotal resections (STRs) 10%, and partial resections 3%. The neurological outcome on postoperative day 1 was as follows: modified McCormick scale (mMS) grade I - 6%, grade II - 21%, grade III - 21%, grade IV - 31%, and grade V - 21%; at follow-up, outcomes were mMS grade I - 42%, grade II - 34%, grade III - 10%, and grade V - 14% of patients. Compared to the preoperative period, 69% of patients deteriorated postoperatively; however, 62% improved or remained without deficit in follow-up, and deterioration persisted in 24%. The functional results were significantly worse when the intraoperative monitoring potentials dropped below 50% (p=0.005) and if the tumor involved >3 spinal levels (p=0.039). Fourteen postoperative complications in 10 patients (34%) included respiratory failure (14%), pneumonia (7%), urinary infection (10%), bed sores (10%), and CSF leak (7%). Two tumors progressed after STR, with progression-free survival times of 5 and 14 years. No recurrence was observed after GTR. CONCLUSIONS: Total tumor resection is the treatment of choice in cases of IEs: no tumor re-growth occurred after total resection, 86% of patients were independent at follow-up, and the 10-year survival rate was 79%.

Diffusion tensor tractography of pyramidal tracts in patients with brainstem and intramedullary spinal cord tumors: Relationship with motor deficits and intraoperative MEP changes.

PURPOSE: To evaluate whether pyramidal tracts course alterations observed in diffusion tensor tractography (DTT) in cases of brainstem and intramedullary spinal cord tumors reflect patient clinical status and prognosis. MATERIALS AND METHODS: For this purpose, we assessed in 17 patients relationships between pyramidal tracts course alterations observed in DTT (classified into four categories: unaffected; displaced or interspaced; partially disintegrated and completely disintegrated) performed on a 1.5 Tesla scanner and the presence of preoperative motor deficits, changes observed in motor evoked potentials (MEPs) records at the beginning of the operation, deterioration of the MEPs records during the operation, and perioperative deterioration of muscle strength. RESULTS: We found that, if the picture of pyramidal tracts in DTT was worse, motor deficit was more common (P = 0.062). This observation was even more evident (P = 0.027), when cases with at least partially destroyed pyramidal tracts were compared with cases with normal or at most displaced or interspaced by tumor but still preserved pyramidal tracts. Significant relationships were also found between changes in DTT and abnormal MEP records at the beginning of the operation (P = 0.032) and perioperative deterioration of muscle strength (P = 0.0058). CONCLUSION: A close relationship was found between pyramidal tracts course alterations in DTT imaging and preoperative motor status and especially with changes in the MEP records at the beginning of the operation. DTT may be a method that allows the better planning of brainstem and intramedullary spinal cord tumors operations and may help in the risk assessment of postoperative motor deficits. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 4 J. MAGN. RESON. IMAGING 2017;46:715-723.

Midline lumbar fusion using cortical bone trajectory screws. Preliminary report.

INTRODUCTION: Midline lumbar fusion (MIDLF) using cortical bone trajectory is an alternative method of transpedicular spinal fusion for degenerative disease. The new entry points' location and screwdriving direction allow the approach-related morbidity to be reduced. AIM: To present our preliminary experience with the MIDLF technique on the first 5 patients with lumbar degenerative disease and with follow-up of at least 6 months. MATERIAL AND METHODS: Retrospective analysis was performed on the first 5 patients with foraminal (4) or central (1) stenosis operated on between December 2014 and February 2015. Three patients were fused at L4-L5 and two at the L5-S1 level. RESULTS: No intra- or post-operative complications occurred with this approach. An improvement regarding the leading symptom in the early postoperative period (sciatica 4/4, claudication 1/1) was achieved in all patients. The mean improvements in the visual analogue scale for low back and leg pain were 2.2 and 4.8 respectively. The mean Oswestry Disability Index scores were 52% (range: 16-82%) before surgery and 33% (range: 12-56%) at 3-month follow-up (mean improvement 19%). At the most recent follow-up, 4 patients reported the maintenance of the satisfactory result. The early standing and follow-up X-rays showed satisfactory screw placement in all patients. CONCLUSIONS: In our initial experience, the MIDLF technique seems to be an encouraging alternative to traditional transpedicular trajectory screws when short level lumbar fusion is needed. Nevertheless, longer observations on larger groups of patients are needed to reliably evaluate the safety of the method and the sustainability of the results.

Surgical treatment of sporadic and von Hippel-Lindau syndrome-associated intramedullary hemangioblastomas.

OBJECT: Intramedullary hemangioblastomas are rare lesions. They can be related to von Hippel-Lindau syndrome or they may be sporadic. This study describes surgical treatment for this infrequent tumor. METHODS: Twelve consecutive patients received surgery to remove sporadic or von Hippel-Lindau syndrome-associated intramedullary hemangioblastomas. Patients were evaluated at four time points: before treatment, on postoperative day one, on the day of discharge, and at a follow-up examination. RESULTS: The patients showed good preoperative neurological status. The cohort had a slight female predominance. All tumors spanned at least one spinal segment. In all cases, total tumor removal was achieved, and a good outcome was obtained. None of the following factors had a significant effect on outcome: age, sex, tumor size, the presence of a syrinx, or the presence of von Hippel-Lindau syndrome. CONCLUSIONS: The surgical removal of intramedullary hemangioblastomas resulted in satisfactory long-term functional outcomes. The best results were obtained before neurological symptoms occurred. Thus, we suggest that surgery should be considered for managing asymptomatic, surgically accessible, space-occupying lesions in sIH group, and isolated, space-occupying lesions in vHLS-IH group.

Oblique corpectomy for treatment of cervical spine epidural abscesses: Report on four cases.

BACKGROUND: Spinal epidural abscesses (SEAs) in cervical locations are particularly life-threatening. Currently, SEAs are widely treated with bony decompression, followed by internal stabilization in purulent osteomyelitis. However, recently, a growing number of studies have reported minimally invasive approaches without internal fixation. PURPOSE: We describe four patients with cervical SEAs that were evacuated by oblique corpectomy (OC) without fusion. METHODS: This study included two women and two men (aged 44-90) that received operations for removing ventral cervical SEAs. All patients presented with progressively increasing myelopathy, and 3 had severe comorbid conditions. In all cases, a multilevel OC without fusion was performed. The amount of bone resection was tailored to fit the needs of granulation removal, with an effort to retain as much of the vertebral bodies as possible. Then, pus was evacuated and debridement of granulation was performed, followed by rinsing and drainage. RESULTS: The neurological status of 3 patients improved significantly after surgery. At the last follow-up examination, one showed full recovery, and in two a minor residual deficit persisted. During mean follow-up of 5.5 years, no internal stabilization was necessary. The oldest patient was tetraplegic, and had several concomitant diseases. That patient died from sudden cardiac arrest on the third postoperative day. Oblique corpectomy did not affect the anterior or posterior column. Additionally, it provided a broad view of the ventral aspect of the spinal canal. CONCLUSIONS: Oblique corpectomy allows appropriate spinal cord decompression and granulation removal in the case of cervical spine epidural abscess, without sacrificing spinal stability.

Sensorimotor C5 and C6 radiculopathy caused by thrombosed vertebral artery dissection and successfully treated with limited oblique corpectomy - Case report.

The authors report the case of an exceptional presentation of vertebral artery dissection. A 44-year-old man who presented with left shoulder weakness, radicular pain and numbness of the left forearm and thumb was admitted to our hospital with an initial diagnosis of cervical disc herniation. Due to the inconsistency between the levels of radiculopathy (C5 and C6) and discopathy (C6-C7), neuroimaging examinations were extended. Based on MRI, MRA, CTA and DSA, left vertebral artery dissection with intramural hematoma was diagnosed. The patient underwent surgical decompression of the affected nerve roots using the anterolateral approach described by Bernard George. The radicular pain resolved immediately and sensorimotor deficit completely disappeared within 4 months. MRI/MRA performed 6 months after surgery showed the normal image of the vertebral artery. There were no ischemic events within 2.5 years of follow-up.

Unusual volume reduction of Galassi grade III arachnoid cyst following head trauma.

We report the case of a 36-year-old woman with a Sylvian fissure arachnoid cyst, which diminished after head trauma and minor hemorrhage into the cyst. We discuss the relationship between the cyst volume reduction and the head trauma to determine the main mechanism of this self-healing process.

Assessment of long-term results of intracranial aneurysm clipping by means of computed tomography angiography.

BACKGROUND AND PURPOSE: The aim of this retrospective study was to assess the effectiveness of aneurysm clipping by computed tomography angiography (CTA) in a long-term follow-up. MATERIAL AND METHODS: The CTA examination was performed in 119 patients who had 143 aneurysms clipped. The examinations were performed 3 to 11 years (mean 6 years) after clipping using a GE Lightspeed PRO16 scanner. RESULTS: In all cases but one, good quality CTA images, suitable for evaluation of the arteries around the clip site, were obtained. Complete aneurysm closure without neck remnant or regrowth was confirmed in 137 (96%) aneurysms. In 4 (3%) cases, neck remnants were detected (2 on the anterior communicating artery [AComA] and 2 on the middle cerebral artery [MCA]). A total clip slippage from the aneurysm dome was revealed in 1 case. One case of aneurysm re-rupture was noted, 11 years after clipping. The rebleeding was caused by AComA aneurysm regrowth. Among these 6 patients with unsatisfactory clipping, 2 required further treatment and 4 remain under observation. Nineteen 'de novo' aneurysms in other locations were found in 14 (12%) patients. Summing up all of the pathological findings in the study group, there were 18 (15%) patients who needed further management including close surveillance or re-treatment. CONCLUSIONS: Computed tomography angiography is a simple and reliable method of aneurysm clipping evaluation. The long- term follow-up CTA confirmed the permanent and complete obliteration of 96% of the aneurysms. The rate of unsatisfactory aneurysm closure was 4%, but only 1.4% needed re-treatment during a mean follow-up of 6 years. The annual risk of aneurysm re-rupture was 0.1%.

Radiation-induced tumours of meninges. Report on eight cases and review of the literature.

BACKGROUND AND PURPOSE: Despite their rarity, post-radiation meningeal tumours seem to be a growing problem due to the increasing application of radiation therapy. The aim of the study was to ascertain the specific features of these tumours. MATERIAL AND METHODS: Among 433 intracranial meningeal tumours treated from 2000 to 2008, eight cases (2%) have been presumed to be associated with high-dose therapeutic radiation for previous neoplasm of the head (7) or neck (1). On average, tumours were diagnosed 24 years after irradiation. All patients had a solitary meningeal tumour, but two of them also developed other neoplasms in the irradiated area. RESULTS: All tumours were microsurgically removed. The post-operative course was uncomplicated in two cases only. In the remaining 6 (75%), complications included liquorrhoea (2), brain oedema (1), venous thrombosis (1), bleeding into the tumour bed (1) and focal deficit due to manipulation (3). Most tumours (5) were WHO grade I meningiomas. These benign meningiomas exhibited some peculiar histological features, including focal increase of cellularity, focal enhancement of proliferation index, pleomorphism of nuclei, occasional mitotic figures and, in one case, evidence of brain invasion. One meningioma was assigned to WHO grade II, one to WHO grade III and one appeared to be meningeal fibrosarcoma. The event-free survival and overall survival rate at 4.4 years of follow-up were 63% and 75%, respectively. CONCLUSIONS: Radiation-induced tumours of the meninges show certain characteristic histopathological features, which may promote invasiveness of the tumour and higher risk of malignancy.