Adverse events during endovascular treatment of ruptured aneurysms: A prospective nationwide study on subarachnoid hemorrhage in Sweden.

Introduction: A range of adverse events (AEs) may occur in patients with subarachnoid hemorrhage (SAH). Endovascular treatment is commonly used to prevent aneurysm re-rupture. Research question: The aim of this study was to identify AEs related to endovascular treatment, analyze risk factors for AEs and how AEs affect patient outcome. Material and methods: Patients with aneurysmal SAH admitted to all neurosurgical centers in Sweden during a 3.5-year period (2014-2018) were prospectively registered. AEs related to endovascular aneurysm treatment were thromboembolic events, aneurysm re-rupture, vessel dissection and puncture site hematoma. Potential risk factors for the AEs were analyzed using multivariate logistic regression. Functional outcome was assessed at one year using the extended Glasgow outcome scale. Results: In total, 1037 patients were treated for ruptured aneurysms. Of which, 715 patients were treated with endovascular occlusion. There were 115 AEs reported in 113 patients (16%). Thromboembolic events were noted in 78 patients (11%). Aneurysm re-rupture occurred in 28 (4%), vessel dissection in 4 (0.6%) and puncture site hematoma in 5 (0.7%). Blister type aneurysm, aneurysm smaller than 5 mm and endovascular techniques other than coiling were risk factors for treatment-related AEs. At follow-up, 230 (32%) of the patients had unfavorable outcome. Patients suffering intraprocedural aneurysm re-rupture were more likely to have unfavorable outcome (OR 6.9, 95% CI 2.3-20.9). Discussion and conclusion: Adverse events related to endovascular occlusion of a ruptured aneurysm were seen in 16% of patients. Aneurysm re-rupture during endovascular treatment was associated with increased risk of unfavorable functional outcome.

Serum neurofilament light as a predictor of outcome in subarachnoid haemorrhage.

BACKGROUND: Prognostication of clinical outcome in patients suffering from aneurysmal subarachnoid haemorrhage (SAH) is a challenge. There are no biochemical markers in routine use that can aid in prognostication. Neurofilament light (NFL) measured in cerebrospinal fluid (CSF) has been associated with clinical outcome in previous studies. OBJECTIVE: To investigate if serum levels of NFL correlate with CSF levels and long-term clinical outcome in patients suffering from SAH. METHODS: We conducted an observational cohort study of 88 patients treated for SAH at Umeå University Hospital in 2014-2018. Serum and CSF samples were analysed using an enzyme-linked immunosorbent assay to quantify NFL levels. Outcome was assessed using Glasgow Outcome Scale Extended and dichotomised as favourable or unfavourable. Differences in NFL levels between outcome groups were analysed using repeated measurements ANOVA. Relationship between CSF and serum NFL levels was analysed using Pearson's correlation. A multivariate binary logistic regression model and a receiver operation characteristic curve were used to assess the predictive value of serum NFL. RESULTS: A significant correlation between serum and CSF-NFL levels could be seen (Pearson's correlation coefficient = 0.7, p < .0001). Mean level of serum NFL was higher in the unfavourable outcome group than the favourable outcome group (p < .0001), in all epochs of SAH, and correlated with initial disease severity on the World Federation of Neurosurgical Societies scale. Serum NFL in the late phase displayed the best predictive potential in a receiver operation characteristic curve analysis (AUC=0.845, p < .0001). CONCLUSION: Levels of NFL in serum and CSF are correlated. Early serum NFL levels seem to reflect initial tissue damage and serum NFL levels in the late phase may reflect secondary events such as vasospasm or delayed cerebral ischemia. Serum NFL may be used as a prognostic marker of clinical outcome in SAH.

Intrasellar Pressure is Related to Endocrine Disturbances in Patients with Pituitary Tumors.

OBJECTIVE: The aim of this study was to investigate the association between intraoperative intrasellar pressure (ISP) and pre- and postoperative endocrine disturbances with focus on hyperprolactinemia and hypopituitarism in patients with pituitary tumors. METHODS: The study is a consecutive, retrospective study with ISP collected prospectively. One hundred patients operated with transsphenoidal surgery due to a pituitary tumor, who had their ISP measured intraoperatively, were included. Data on patient endocrine status preoperatively and from 3-month postoperative follow-up were collected from medical records. RESULTS: The risk of preoperative hyperprolactinemia in patients with nonprolactinoma pituitary tumors increased with ISP (unit odds ratio 1.067, n = 70) (P = 0.041). Preoperative hyperprolactinemia was normalized at 3 months after surgery. Mean ISP was higher in patients with preoperative thyroid-stimulating hormone (TSH) deficiency (25.3 ± 9.2 mmHg, n = 37) than in patients with intact thyroid axis (21.6 ± 7.2 mmHg, n = 50) (P = 0.041). No significant difference in ISP was found between patients with and without adrenocorticotropic hormone(ACTH) deficiency. No association was found between ISP and postoperative hypopituitarism at 3 months after surgery. CONCLUSIONS: In patients with pituitary tumors, preoperative hypothyroidism and hyperprolactinemia may be associated with higher ISP. This is in line with the theory of pituitary stalk compression, suggested to be mediated by an elevated ISP. ISP does not predict the risk of postoperative hypopituitarism 3 months after surgical treatment.

Adverse events associated with microsurgial treatment for ruptured intracerebral aneurysms: a prospective nationwide study on subarachnoid haemorrhage in Sweden.

BACKGROUND: Adverse events (AEs) or complications may arise secondary to the treatment of aneurysmal subarachnoid haemorrhage (SAH). The aim of this study was to identify AEs associated with microsurgical occlusion of ruptured aneurysms, as well as to analyse their risk factors and impact on functional outcome. METHODS: Patients with aneurysmal SAH admitted to the neurosurgical centres in Sweden were prospectively registered during a 3.5-year period (2014-2018). AEs were categorised as intraoperative or postoperative. A range of variables from patient history and SAH characteristics were explored as potential risk factors for an AE. Functional outcome was assessed approximately 1 year after the bleeding using the extended Glasgow Outcome Scale. RESULTS: In total, 1037 patients were treated for ruptured aneurysms, of which, 322 patients were treated with microsurgery. There were 105 surgical AEs in 97 patients (30%); 94 were intraoperative AEs in 79 patients (25%). Aneurysm rerupture occurred in 43 patients (13%), temporary occlusion of the parent artery >5 min in 26 patients (8%) and adjacent vessel injury in 25 patients (8%). High Fisher grade and brain oedema on CT were related to increased risk of AEs. At follow-up, 38% of patients had unfavourable outcome. Patients suffering AEs were more likely to have unfavourable outcome (OR 2.3, 95% CI 1.10 to 4.69). CONCLUSION: Intraoperative AEs occurred in 25% of patients treated with microsurgery for ruptured intracerebral aneurysm in this nationwide survey. Although most operated patients had favourable outcome, AEs were associated with increased risk of unfavourable outcome.

[Considerations when handling common acute intracranial vascular anomalies]. / Akuta vaskulära neurokirurgiska tillstånd kräver snabb hantering.

Conditions involving intracranial vascular anomalies are increasingly diagnosed, not least incidentally, with the increasing availability of neuroradiological investigations. Acute deterioration and development of symptoms due to a vascular condition could require neurosurgical intervention depending on the nature of the condition and status of the patient. On the other hand, asymptomatic patients with incidental findings require careful consideration and risk assessment when deciding on whether or not to treat the condition, and if so, how. In this review article we provide a summary of some of the most common neurosurgical vascular conditions and outline management considerations in both the acute and elective setting.

The impact of previous health on the mortality after aneurysmal subarachnoid hemorrhage: analysis of a prospective Swedish multicenter study.

PURPOSE: There is an an increasing awareness of the importance of health and lifestyle for stroke diseases like spontaneous subarachnoid hemorrhage (SAH). However, the importance of pre-existing medical conditions for clinical course and mortality after SAH has not been studied. The aim of the present study was to identify pre-existing conditions contributing to mortality after SAH. METHODS: Data were extracted from a Swedish national prospective study on patients with SAH. Variables were defined for age, sex, body mass index (BMI), clinical condition at admission, and for 10 pre-existing medical conditions. Models predicting mortality in three time intervals with all possible subsets of these variables were generated, compared and selected using Akaike's information criterion. RESULTS: 1155 patients with ruptured aneurysms were included. The mortality within 1 week was 7.6%, 1 month 14.3%, and 1 year 18.7%. The most common pre-existing medical conditions were smoking (57.6%) and hypertension (38.7%). The model's best predicting mortality within 1 week and from 1 week to 1 month included only the level of consciousness at admission and age, and these two variables were present in all the models among the top 200 in Akaike score for each time period. The most predictive model for mortality between 1 month and 1 year added previous stroke, diabetes, psychiatric disease, and BMI as predictors. CONCLUSION: Mortality within the first month was best predicted simply by initial level of consciousness and age, while mortality within from 1 month to 1 year was significantly influenced by pre-existing medical conditions.

Serum Levels of Myo-inositol Predicts Clinical Outcome 1 Year After Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Early prognostication of long-term outcome in patients suffering from spontaneous subarachnoid hemorrhage (SAH) remains a challenge. No biomarkers are routinely used for prognostication. A previous study has indicated that the metabolite myo-inositol (MI) may be used to predict long-term outcome. OBJECTIVE: To investigate if MI measured in serum correlates with long-term clinical outcome in patients suffering from SAH. METHODS: We conducted an observational cohort study including 88 patients treated for SAH at Umeå University Hospital. Serum samples were collected in the hospital, and a gas chromatography/mass spectroscopy method was used to quantitatively measure MI. Patients were assessed after 1 year using the Glasgow Outcome Scale Extended and dichotomized to favorable or unfavorable outcome. Differences in MI levels between the 2 groups were analyzed. RESULTS: There was no difference in MI levels between the groups upon admission. Myo-inositol levels decreased over time in the entire study population. The decrease was significantly larger in the unfavorable outcome group. A receiver operating characteristics analysis yielded an area under the curve of 0.903 (CI 0.8-1.0, P < .001) for the MI value on day 7 to predict favorable outcome after 1 year. CONCLUSION: Myo-inositol measured in serum may aid prognostication of outcome in patients with SAH. The mechanism behind this remains unclear, although it can be theorized to reflect processes leading to delayed cerebral ischemia, which affects long-term outcome. This is the first study to quantitively measure MI in serum for prognostication of outcome in patients with SAH.

Serum S100B correlates with health-related quality of life and functional outcome in patients at 1 year after aneurysmal subarachnoid haemorrhage.

BACKGROUND: Early, objective prognostication after aneurysmal subarachnoid haemorrhage (aSAH) is difficult. A biochemical marker would be desirable. Correlation has been found between levels of the protein S100 beta (S100B) and outcome after aSAH. Timing and clinical usefulness are under investigation. METHODS: Eighty-nine patients admitted within 48 h of aSAH were included. Modified ranking scale (mRS), EuroQoL health-related quality of life measure (EQ-5Dindex) and EuroQoL visual analogue scale (EQ-VAS) values were evaluated after 1 year. S100B was measured in blood samples collected at admission and up to day 10. RESULTS: S100B correlated significantly with EQ-5Dindex and mRS, but not EQ-VAS at 1 year after aSAH. A receiver operating characteristic analysis for peak S100B values (area under the curve 0.898, 95% confidence interval 0.828-0.968, p < 0.0001), with a cutoff of 0.4 µg/l, yielded 95.3% specificity and 68% sensitivity for predicting unfavourable outcome. Dichotomized S100B (> 0.4 µg/l vs ≤ 0.4 µg/l), age and Hunt and Hess grading scale score (HH) were associated with unfavourable mRS outcome in univariate logistic regression analysis. Dichotomized S100B was the only variable independently correlated with unfavourable mRS outcome in a multivariate logistic regression analysis. CONCLUSIONS: For the first time, S100B was shown to correlate with mRS and health-related quality of life at 1 year after aSAH. Peak S100B can be used as a prognostic factor for unfavourable outcome measured as dichotomized mRS after aSAH. A peak value cutoff of 0.4 µg/l is suggested. Ethical approval no: 2013/366-31, 4th of February 2014.

Intrasellar pressure in patients with pituitary adenoma - relation to tumour size and growth pattern.

BACKGROUND: Only a few earlier publications on intrasellar pressure (ISP) have not been able to fully clarify any association between ISP and pituitary adenoma size and growth pattern. The aim of the study was to determine if intrasellar pressure (ISP) is elevated in patients with pituitary adenoma, and if the pressure is associated with tumour size and growth pattern. METHODS: The study included 100 patients operated for suspected pituitary adenoma, who have had their ISP measured intraoperatively. All adenomas were classified on the basis of Knosp and SIPAP, from which further classification of invasiveness was performed. MRT examinations were used to calculate the tumour volume and diameter in three axes. RESULTS: After exclusions, 93 cases were analysed. The mean ISP was 23.0 ± 8.4 mmHg. There were positive correlations between ISP and tumour volume and tumour diameters along all three axes. Coronal tumour diameter showed the strongest correlation with ISP elevation in a multivariate effect test. Adenomas classified as parasellar invasive (Knosp grade 3-4) showed higher mean ISP than adenomas considered as non-invasive (Knosp 0-2). CONCLUSIONS: ISP is affected by tumour anatomy and correlates positively with tumour volume. Tumour width, i.e. diameter in the coronal plane, appears to be the measure that most strongly affects the ISP. This is confirmed by the association between ISP elevation and parasellar growth.

Treatment of restless legs syndrome with a pump; efficacy and complications.

OBJECTIVES: Restless legs syndrome (RLS) has a prevalence of 2.5%-15% in the general population. For those who suffer from a medically refractory RLS, intrathecal morphine treatment has been shown to be effective. The aim of this retrospective study was to investigate efficacy, complications and side effects in patients treated over several years with an implantable pump. A comparison was done to a group of patients treated with a similar pump system due to spasticity. MATERIALS AND METHODS: The charts of ten patients with severe or very severe RLS have been reviewed. These patients have received an intrathecal drug delivery system during 2000-2016. To compare the rate of complications, a control group of 20 patients treated with intrathecal baclofen due to spasticity was included in the study. Their time of treatment corresponded to the RLS patients. RESULTS: The severity of symptoms related to RLS decreased significantly after treatment. Doses required ranged from 68 to 140 µg/d. Two cases of side effects were detected; one case with nausea and dizziness and one case with headache and fatigue. The rate of mechanical, infectious and other complications was similar between the two groups. CONCLUSIONS: In light of the decrease in symptom severity and the low rate of side effects, intrathecal morphine can be considered an adequate treatment for those suffering from medically refractory RLS. The occurrence of complications did not differ between subjects with RLS and spasticity.

Scandinavian Multicenter Acute Subdural Hematoma (SMASH) Study: Study Protocol for a Multinational Population-Based Consecutive Cohort.

BACKGROUND: Traumatic acute subdural hematomas (ASDHs) are associated with high rate of morbidity and mortality, especially in elderly individuals. However, recent reports indicate that the morbidity and mortality rates might have improved. OBJECTIVE: To evaluate postoperative (30-d) mortality in younger vs elderly (≥70 yr) patients with ASDH. Comparing younger and elderly patients, the secondary objectives are morbidity patterns of care and 6 mo outcome according to Glasgow outcome scale (GOS). Finally, in patients with traumatic ASDH, we aim to provide prognostic variables. METHODS: This is a large-scale population-based Scandinavian study including all neurosurgical departments in Denmark and Sweden. All adult (≥18 yr) patients surgically treated between 2010 and 2014 for a traumatic ASDH in Denmark and Sweden will be included. Identification at clinicaltrials.gov is NCT03284190. EXPECTED OUTCOMES: We expect to provide data on potential differences between younger vs elderly patients in terms of mortality and morbidity. We hypothesize that elderly patients selected for surgery have a similar pattern of care as compared with younger patients. We will provide functional outcome in terms of GOS at 6 mo in younger vs elderly patients undergoing ASDH evacuation. Finally, clinical useful prognostic factors for favorable (GOS 4-5) vs unfavorable (GOS 1-3) will be identified. DISCUSSION: An improved understanding of the clinical outcome, treatment and resource allocation, clinical course, and the prognostic factors of traumatic ASDH will allow neurosurgeons to make better treatment decisions.

Identifying Unmet Rehabilitation Needs in Patients After Stroke With a Graphic Rehab-CompassTM.

BACKGROUND: Unmet rehabilitation needs are common among stroke survivors. We aimed to evaluate whether a comprehensive graphic "Rehab-Compass," a novel combination of structured patient-reported outcome measures, was feasible and useful in facilitating a capture of patients' rehabilitation needs in clinical practice. METHODS: A new graphic overview of broad unmet rehabilitation needs covers deficits in functioning, daily activity, participation, and quality of life. It was constructed by using 5 patient-oriented, well-validated, and reliable existing instruments with converted data into a 0 (worst outcome) to 100 (best outcome) scale but unchanged in terms of variable properties. Satisfaction of the Rehab-CompassTM was studied by a qualitative interview of 9 patients with stroke and 3 clinicians. Practical feasibility and capacity of the instrument were evaluated in a cross-sectionalstudy with 48 patients at 5-month follow-ups after subarachnoid hemorrhage. RESULTS: The Rehab-CompassTM identified and graphically visualized a panoramic view of the multidimensional needs over time which was completed before clinical consultation. The Rehab-CompassTM appeared to be feasible and time-efficientin clinical use. The interviews of both patients and clinicians showed high satisfaction when using the Rehab-CompassTM graph. In the studied stroke patients, the Rehab-CompassTM identified memory and processing information, fatigue, mood, and pain after subarachnoid hemorrhage as the most common problems. CONCLUSIONS: The graphic Rehab-CompassTM seems to be a feasible, useful, and time-saving tool for identification of unmet rehabilitation needs among stroke survivors in clinical practice. Further research is needed to make the Rehab-CompassTM more concise and evaluate the instrument among different stroke subgroups.

Hypofractionated stereotactic radiotherapy in medium-sized to large arteriovenous malformations.

We have reviewed treatment results in terms of obliteration and complications in 24 patients with medium to large sized cerebral arteriovenous malformations (AVMs) (mean volume 18.5±8.9cm(3); range: 10-42) treated with hypofractionated stereotactic radiotherapy (HSRT). AVMs are congenital lesions associated with a high morbidity and mortality. Radiosurgery is one option for treatment. However, in larger AVMs with volumes exceeding 10cm(3) obliteration rates are less favourable and radiation induced complications more frequent. For larger AVMs, volume-staged radiosurgery is one option while another option may be the use of HSRT. Patients were treated with 6-7Gy in five fractions to a total dose of 30-35Gy (mean total dose 32.9±1.6Gy [standard error of the mean]). Sixteen patients (69.6%) showed obliteration after a mean time of 35.2±14.8 months (range: 24-60). Only one patient (4.2%) experienced symptomatic radionecrosis. Our treatment with HSRT seems safe and efficient for treatment of medium to large sized AVMs. Treatment results seem to be in line with volume-staged radiosurgery and may be an alternative for AVMs not suitable for single fraction radiosurgery.

Blood Metabolomic Predictors of 1-Year Outcome in Subarachnoid Hemorrhage.

BACKGROUND: Delayed neurological deficit (DND) is the most important cause of morbidity and mortality in patients with subarachnoid hemorrhage (SAH) whose aneurysms have been secured. However, the methods currently used to predict the development of DND, such as trans-cranial Doppler or levels biochemical markers in blood and cerebrospinal fluid are not very accurate. METHOD: Venous blood was drawn from 50 patients with SAH, admitted to the neurosurgical department Umeå University Hospital, at day 1-3 and day 7 after the bleed. The clinical status of the patients was followed up approximately 1 year after this episode and classified according to the Glasgow Outcome Score (GOS). RESULTS: Results showed considerable differences in blood metabolomic patterns between day 1-3 and 7 after the hemorrhage. Fifty-six out of 98 metabolites could be identified from our in-house library and 17 of these metabolites changed significantly from day 1-3 to 7 after the bleed. One of these, myo-inositol, was predictive of clinical outcome even after correction for multiple testing. An estimation of the diagnostic accuracy of high levels of this substance in predicting good outcome (GOS 4-5) yielded a sensitivity of .763 and a specificity of .5 at the optimal cut off point. CONCLUSIONS: SAH is an event with a profound effect on blood metabolomics profiles. Myo-inositol might be an interesting compound for future study to focus on in the search for metabolic markers in venous blood of delayed neurological deterioration in SAH patients.

ADMA levels and arginine/ADMA ratios reflect severity of disease and extent of inflammation after subarachnoid hemorrhage.

BACKGROUND: Subarachnoid hemorrhage (SAH) is characterized by an inflammatory response that might induce endothelial dysfunction. The aim of this study was to evaluate if ADMA and arginine/ADMA ratios after SAH (indicators of endothelial dysfunction) are related to clinical parameters, inflammatory response, and outcome. METHODS: Prospective observational study. ADMA, arginine, C-reactive protein (CRP), and cytokines were obtained 0-240 h (h) after SAH. Definition of severe clinical condition was Hunt&Hess (H&H) 3-5 and less severe clinical condition H&H 1-2. Impaired cerebral circulation was assessed by clinical examination, transcranial doppler, CT-scan, and angiography. Glasgow outcome scale (GOS) evaluated the outcome. RESULTS: Compared to admission, 0-48 h after SAH, the following was observed 49-240 h after SAH; (a) ADMA was significantly increased at 97-240 h (highest 217-240 h), (b) CRP was significantly increased at 49-240 h (highest 73-96 h), (c) interleukin-6 (IL-6) was significantly lower at 97-240 h (highest 49-96 h), p < 0.05. ADMA, CRP, and IL-6 were significantly lower and peak arginine/ADMA ratio was significantly higher in patients with H&H 1-2 compared to patients with H&H 3-5, p < 0.05. The peak ADMA or the nadir arginine/ADMA ratio did not differ significantly between patients with (55%) or without (45%) signs of impaired cerebral circulation. The peak ADMA or the nadir arginine/ADMA ratio did not differ significantly between patients with GOS 1-3 and patients with GOS 4-5. CONCLUSIONS: ADMA increased significantly after SAH, and the increase in ADMA started after the pro-inflammatory markers (CRP and IL-6) had peaked. This might indicate that endothelial dysfunction, with ADMA as a marker, is induced by a systemic inflammation.

Intracranial Hypertension due to Cerebral Venous Sinus Thrombosis following Head Trauma: A Report of Two Cases.

Cerebral venous sinus thrombosis (CVST) may occur following head trauma and contribute to intracranial hypertension that mandates immediate action. Anticoagulant therapy is the first line of treatment in CVST but may not be applicable in patients with head trauma. Here, we report on the treatment of 2 patients with CVST. In 1 patient, there was an attempt to perform thrombectomy and thrombolysis, and eventually a decompressive craniectomy was performed. In this patient, there was an excellent outcome. In the other patient, an immediate decompressive craniectomy was performed that did not improve the outcome.

Complications following cranioplasty using autologous bone or polymethylmethacrylate--retrospective experience from a single center.

OBJECTIVE: A decompressive hemicraniectomy is a potentially life-saving intervention following head trauma. Once performed patients are obliged to undergo a second procedure with cranioplasty. Two of the most commonly used materials are autologous bone and polymethylmethacrylate (PMMA). We have now evaluated complications following a cranioplasty using these materials. MATERIALS AND METHODS: During a 7-year period (2002-2008) 49 patients were operated with a decompressive craniectomy following head trauma. Patients received a cranioplasty consisting of autologous bone (30 patients, 61.2%) or PMMA (19 patients, 38.8%) and were followed at least 24 months. Patient data were collected retrospectively. RESULTS: Twenty patients (20/49, 40.8%) experienced a complication that prompted a re-operation. There was a significantly higher rate of complications leading to a re-operation (53.3% vs. 21.1%, p=0.03) and a shorter survival time of the cranioplasty (mean 48.1 ± 7.8 vs. 79.5 ± 9.0 months, p=0.035) in patients with autologous bone compared to PMMA. Bone resorption and the presence of postoperative hematomas were significantly more common in patients with autologous bone. The material used for cranioplasty was the only variable that significantly correlated to the rate of complications. CONCLUSIONS: In our series we had a high percentage of patients needing re-operation due to complications following a cranioplasty. Though generally considered a straightforward procedure, complications and associated morbidity in patients undergoing cranioplasty should not be underestimated.

Long-term follow-up of intracranial aneurysms treated with endovascular coiling: experience from one institution.

BACKGROUND: Our aim was to evaluate the long-term treatment results in patients with intracranial aneurysms treated with endovascular techniques. METHODS: Forty-four patients treated due to intracranial aneurysms between 1996 and 2002 were investigated with a time-of-flight sequence magnetic resonance angiography (TOF MRA). RESULTS: Depending on the assessment, 47% to 51% of the treated aneurysms had a residual neck at the last digital subtraction angiography follow-up. There was filling of the aneurysm base (2%) in only 1 patient, whereas the remaining aneurysms were totally occluded. A TOF MRA performed 6 to 14 (mean 9.68) years after the last procedure showed a stable result in 93.9% of the treated aneurysms. There were no de novo aneurysms and previously untreated aneurysms were unchanged in size. CONCLUSION: Our long-term follow-up showed a stable result in previously coiled intracranial aneurysms.

Reoperation after failed deep brain stimulation for essential tremor.

OBJECTIVE: To evaluate the effects of reoperation with deep brain stimulation (DBS) in the caudal zona incerta (cZi) in patients with failed DBS in the ventral intermediate (Vim) nucleus of the thalamus for essential tremor. METHODS: The results of reoperation with cZi DBS in five patients with failed Vim DBS were retrospectively analyzed. RESULTS: Two patients had early failure of Vim DBS, and three after several years of good effect. The mean deviation from the atlas Vim target point was 1.4 mm. Before the reoperation Vim DBS improved hand function and tremor in the treated hand at 25 %, whereas cZi DBS achieved an improvement of 57%. Although cZi was more efficient than Vim DBS, also in the patients with late failure of Vim DBS, they still exhibited a considerable residual tremor on cZi DBS. CONCLUSIONS: The effect on tremor was, in this small sample population, improved by implanting an electrode in the cZi. The effect was modest in those patients suffering a deterioration years after the initial operation.