Clinical and Brain Morphometry Predictors of Deep Brain Stimulation Outcome in Parkinson's Disease.

Subthalamic deep brain stimulation (STN-DBS) is known to improve motor function in advanced Parkinson's disease (PD) and to enable a reduction of anti-parkinsonian medication. While the levodopa challenge test and disease duration are considered good predictors of STN-DBS outcome, other clinical and neuroanatomical predictors are less established. This study aimed to evaluate, in addition to clinical predictors, the effect of patients' individual brain topography on DBS outcome. The medical records of 35 PD patients were used to analyze DBS outcomes measured with the following scales: Part III of the Unified Parkinson's Disease Rating Scale (UPDRS-III) off medication at baseline, and at 6-months during medication off and stimulation on, use of anti-parkinsonian medication (LED), Abnormal Involuntary Movement Scale (AIMS) and Non-Motor Symptoms Questionnaire (NMS-Quest). Furthermore, preoperative brain MRI images were utilized to analyze the brain morphology in relation to STN-DBS outcome. With STN-DBS, a 44% reduction in the UPDRS-III score and a 43% decrease in the LED were observed (p<0.001). Dyskinesia and non-motor symptoms decreased significantly [median reductions of 78,6% (IQR 45,5%) and 18,4% (IQR 32,2%) respectively, p=0.001 - 0.047]. Along with the levodopa challenge test, patients' age correlated with the observed DBS outcome measured as UPDRS-III improvement (ρ= -0.466 - -0.521, p<0.005). Patients with greater LED decline had lower grey matter volumes in left superior medial frontal gyrus, in supplementary motor area and cingulum bilaterally. Additionally, patients with greater UPDRS-III score improvement had lower grey matter volume in similar grey matter areas. These findings remained significant when adjusted for sex, age, baseline LED and UPDRS scores respectively and for total intracranial volume (p=0.0041- 0.001). However, only the LED decrease finding remained significant when the analyses were further controlled for stimulation amplitude. It appears that along with the clinical predictors of STN-DBS outcome, individual patient topographic differences may influence DBS outcome. Clinical Trial Registration Number: NCT06095245, registration date October 23, 2023, retrospectively registered.

Natural history of intracavernous aneurysms: a consecutive single-center study of 250 patients with 276 aneurysms.

OBJECTIVE: The natural history of cavernous carotid aneurysms (CCAs) is not fully understood. For robust clinical decision-making, the behavior of CCAs needs to be fully understood. The objective of this paper was to calculate the mortality and morbidity rates of patients with diagnosed but untreated CCAs from a relatively large single-center cohort. METHODS: The authors identified 250 patients with 276 CCAs from August 1946 to August 2017 from an aneurysm database including 12,000 intracranial aneurysm patients. Patient and aneurysm characteristics were extracted for further analysis. RESULTS: The cumulative patient follow-up was 1560 years, with a mean of 6.3 years. For patients presenting with a cranial nerve deficit caused by a CCA, those with a ruptured CCA, and patients who received treatment for a CCA, the cumulative patient follow-up was 121 years, with a mean of 1.3 years. For patients with symptom-free or conservatively treated CCAs, the cumulative patient follow-up was 1093 years, with a mean of 7.2 years. Of the 276 aneurysms, 57 (21%) caused cranial nerve deficits and 18 (6.5%) other symptoms, while 201 (73%) remained symptom free. A total of 264 (96%) of the CCAs remained unruptured, and 2 were considered possibly ruptured. Ten (3.6%) ruptures of the CCAs were found. However, none of the ruptured aneurysms caused subarachnoid hemorrhage or death of the patient. Of the CCAs, 51 were multiple, and 131 patients had ≥ 1 intradural aneurysm. The CCAs were analyzed separately. CONCLUSIONS: The majority of the CCAs were asymptomatic during follow-up, and none caused the death of the patient. The incidence of symptoms increased with aneurysm size. Because CCAs have a benign natural course, treatment should be considered mainly if the CCA is symptomatic or grows during follow-up.

Anterior inferior cerebellar artery (AICA) aneurysms: a radiological study of 15 consecutive patients.

Introduction: The aneurysms of the anterior inferior cerebellar artery (AICA) are rare lesions of the posterior circulation and to treat them is challenging. We aim to present anatomical and morphological characteristics of AICA aneurysms in a series of 15 patients. Method: The DSA and CT angiography images of AICA aneurysms in 15 consecutive patients were analyzed retrospectively. Different anatomical characteristics were quantified, including morphology, location, width, neck width, length, bottleneck factor, and aspect ratio. Results: Eighty percent of the patients were females. The age was 52.4 ± 9.6 (mean ± SD) years. 11 patients were smokers. Ten patients had a saccular aneurysm and five patients had a fusiform aneurysm. Aneurysm in 10 patients were located in the proximal segment, in three patients in the meatal segment, and in two patients in the distal segment. Ten out of 15 patients presented with a ruptured aneurysm. The size of AICA aneurysms was 14.8 ± 18.9 mm (mean ± SD). The aspect ratio was 0.92 ± 0.47 (mean ± SD) and bottleneck factor was 1.66 ± 1.65 (mean ± SD). Conclusion: AICA aneurysms are rare lesions of posterior circulation predominantly found in females, present predominantly with subarachnoid hemorrhage, and are mostly large in size.

Intraputamenal Cerebral Dopamine Neurotrophic Factor in Parkinson's Disease: A Randomized, Double-Blind, Multicenter Phase 1 Trial.

BACKGROUND: Cerebral dopamine neurotrophic factor (CDNF) is an unconventional neurotrophic factor that protects dopamine neurons and improves motor function in animal models of Parkinson's disease (PD). OBJECTIVE: The primary objectives of this study were to assess the safety and tolerability of both CDNF and the drug delivery system (DDS) in patients with PD of moderate severity. METHODS: We assessed the safety and tolerability of monthly intraputamenal CDNF infusions in patients with PD using an investigational DDS, a bone-anchored transcutaneous port connected to four catheters. This phase 1 trial was divided into a placebo-controlled, double-blind, 6-month main study followed by an active-treatment 6-month extension. Eligible patients, aged 35 to 75 years, had moderate idiopathic PD for 5 to 15 years and Hoehn and Yahr score ≤ 3 (off state). Seventeen patients were randomized to placebo (n = 6), 0.4 mg CDNF (n = 6), or 1.2 mg CDNF (n = 5). The primary endpoints were safety and tolerability of CDNF and DDS and catheter implantation accuracy. Secondary endpoints were measures of PD symptoms, including Unified Parkinson's Disease Rating Scale, and DDS patency and port stability. Exploratory endpoints included motor symptom assessment (PKG, Global Kinetics Pty Ltd, Melbourne, Australia) and positron emission tomography using dopamine transporter radioligand [18 F]FE-PE2I. RESULTS: Drug-related adverse events were mild to moderate with no difference between placebo and treatment groups. No severe adverse events were associated with the drug, and device delivery accuracy met specification. The severe adverse events recorded were associated with the infusion procedure and did not reoccur after procedural modification. There were no significant changes between placebo and CDNF treatment groups in secondary endpoints between baseline and the end of the main and extension studies. CONCLUSIONS: Intraputamenally administered CDNF was safe and well tolerated, and possible signs of biological response to the drug were observed in individual patients. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Treatment and Outcome of Anterior Inferior Cerebellar Artery (AICA) Aneurysms: Helsinki Series of 15 Consecutive Patients.

Objective Anterior inferior cerebellar artery (AICA) aneurysms are rare posterior circulation lesions that are challenging to treat. This article presents the treatment and clinical outcome of AICA aneurysms in an unselected cohort of patients. Methods A retrospective analysis of patient record files, digital subtraction angiography, and computed tomography angiography images of 15 consecutive patients harboring AICA aneurysms treated between 1968 and 2017. Results Of the 15 AICA aneurysm patients reviewed, 12 (80%) were females. Twenty percent had intracerebral hemorrhage and 40% presented with intraventricular hemorrhage. Eleven out of 15 (73%) patients presented with subarachnoid hemorrhage (SAH); 82% of SAH patients had a good-grade SAH (Hunt and Hess grade 1-3). Eleven patients (73%) were treated surgically, three (20%) were treated conservatively, and one (7%) had coil embolization. In 27% of patients, a subtemporal approach with anterior petrosectomy was performed. A retrosigmoid approach was used in the remaining 73%. In 18% of the patients, a parent vessel occlusion was necessary to occlude the aneurysm. Five out of 11 (47%) of the patients developed postoperative cranial nerve deficits. Twenty-seven percent developed shunt-dependent hydrocephalus. All patients who presented with an unruptured AICA aneurysm had good clinical outcome (modified Rankin scale [mRS] 1-2). In patients with SAH, 82% achieved good clinical outcome and 18% had poor clinical outcome (mRS 3-6) after 1 year. Conclusion Surgical treatment of AICA aneurysms has a high rate of cranial nerve deficits but most of patients have a good long-term clinical outcome.

Zero-heat-flux thermometry over the carotid artery in assessment of core temperature in craniotomy patients.

Zero-heat-flux core temperature measurements on the forehead (ZHF-forehead) show acceptable agreement with invasive core temperature measurements but are not always possible in general anesthesia. However, ZHF measurements over the carotid artery (ZHF-neck) have been shown reliable in cardiac surgery. We investigated these in non-cardiac surgery. In 99 craniotomy patients, we assessed agreement of ZHF-forehead and ZHF-neck (3M™ Bair Hugger™) with esophageal temperatures. We applied Bland-Altman analysis and calculated mean absolute differences (difference index) and proportion of differences within ± 0.5 °C (percentage index) during entire anesthesia and before and after esophageal temperature nadir. In Bland-Altman analysis [mean (limits of agreement)], agreement with esophageal temperature during entire anesthesia was 0.1 (-0.7 to +0.8) °C (ZHF-neck) and 0.0 (-0.8 to +0.8) °C (ZHF-forehead), and, after core temperature nadir, 0.1 (-0.5 to +0.7) °C and 0.1 (-0.6 to +0.8) °C, respectively. In difference index [median (interquartile range)], ZHF-neck and ZHF-forehead performed equally during entire anesthesia [ZHF-neck: 0.2 (0.1-0.3) °C vs ZHF-forehead: 0.2 (0.2-0.4) °C], and after core temperature nadir [0.2 (0.1-0.3) °C vs 0.2 (0.1-0.3) °C, respectively; all p > 0.017 after Bonferroni correction]. In percentage index [median (interquartile range)], both ZHF-neck [100 (92-100) %] and ZHF-forehead [100 (92-100) %] scored almost 100% after esophageal nadir. ZHF-neck measures core temperature as reliably as ZHF-forehead in non-cardiac surgery. ZHF-neck is an alternative to ZHF-forehead if the latter cannot be applied.

Intracranial Aneurysm Classifier Using Phenotypic Factors: An International Pooled Analysis.

Intracranial aneurysms (IAs) are usually asymptomatic with a low risk of rupture, but consequences of aneurysmal subarachnoid hemorrhage (aSAH) are severe. Identifying IAs at risk of rupture has important clinical and socio-economic consequences. The goal of this study was to assess the effect of patient and IA characteristics on the likelihood of IA being diagnosed incidentally versus ruptured. Patients were recruited at 21 international centers. Seven phenotypic patient characteristics and three IA characteristics were recorded. The analyzed cohort included 7992 patients. Multivariate analysis demonstrated that: (1) IA location is the strongest factor associated with IA rupture status at diagnosis; (2) Risk factor awareness (hypertension, smoking) increases the likelihood of being diagnosed with unruptured IA; (3) Patients with ruptured IAs in high-risk locations tend to be older, and their IAs are smaller; (4) Smokers with ruptured IAs tend to be younger, and their IAs are larger; (5) Female patients with ruptured IAs tend to be older, and their IAs are smaller; (6) IA size and age at rupture correlate. The assessment of associations regarding patient and IA characteristics with IA rupture allows us to refine IA disease models and provide data to develop risk instruments for clinicians to support personalized decision-making.

Real-Life Experience on Directional Deep Brain Stimulation in Patients with Advanced Parkinson's Disease.

Directional deep brain stimulation (dDBS) is preferred by patients with advanced Parkinson's disease (PD) and by programming neurologists. However, real-life data of dDBS use is still scarce. We reviewed the clinical data of 53 PD patients with dDBS to 18 months of follow-up. Directional stimulation was favored in 70.5% of dDBS leads, and single segment activation (SSA) was used in 60% of dDBS leads. Current with SSA was significantly lower than with other stimulation types. During the 6-month follow-up, a 44% improvement in the Unified Parkinson's Disease Rating Scale (UPDRS-III) points and a 43% decline in the levodopa equivalent daily dosage (LEDD) was observed. After 18 months of follow-up, a 35% LEDD decrease was still noted. The Hoehn and Yahr (H&Y) stages and scores on item no 30 "postural stability" in UPDRS-III remained lower throughout the follow-up compared to baseline. Additionally, dDBS relieved non-motor symptoms during the 6 months of follow-up. Patients with bilateral SSA had similar clinical outcomes to those with other stimulation types. Directional stimulation appears to effectively reduce both motor and non-motor symptoms in advanced PD with minimal adverse effects in real-life clinical care.

Deep brain stimulation of subthalamic nucleus modulates cortical auditory processing in advanced Parkinson's Disease.

Deep brain stimulation (DBS) has proven its clinical efficacy in Parkinson's disease (PD), but its exact mechanisms and cortical effects continue to be unclear. Subthalamic (STN) DBS acutely modifies auditory evoked responses, but its long-term effect on auditory cortical processing remains ambiguous. We studied with magnetoencephalography the effect of long-term STN DBS on auditory processing in patients with advanced PD. DBS resulted in significantly increased contra-ipsilateral auditory response latency difference at ~100 ms after stimulus onset compared with preoperative state. The effect is likely due to normalization of neuronal asynchrony in the auditory pathways. The present results indicate that STN DBS in advanced PD patients has long-lasting effects on cortical areas outside those confined to motor processing. Whole-head magnetoencephalography provides a feasible tool to study motor and non-motor neural networks in PD, and to track possible changes related to cortical reorganization or plasticity induced by DBS.

Incidence of surgery for chronic subdural hematoma in Finland during 1997-2014: a nationwide study.

OBJECTIVE: The number of surgeries performed for chronic subdural hematoma (CSDH) has increased. However, these changes have been poorly reported. The authors aimed to assess the national incidence of surgeries for CSDH in Finland during an 18-year time period from 1997 to 2014. They hypothesized that the incidence of CSDH surgeries has continued to increase, particularly among the elderly. METHODS: A nationwide register-based follow-up study was performed using the Finnish Care Register for Health Care. All adult patients undergoing primary CSDH surgeries during 1997-2014 were included. The study population was followed up from the time of CSDH surgery until death or the end of follow-up on December 31, 2017. The incidences of CSDH surgery per 100,000 person-years were calculated separately in each age group and sex. Age standardization was performed for those 20 years of age and older with weights from the 2013 European Standard Population. Negative binomial regression models were used to assess changes in incidence rate ratios (IRRs) during the study period. RESULTS: In total, 9280 patients were identified. The age-standardized incidence of CSDH surgery increased from 12.2 to 16.5 per 100,000 person-years during 1997-2014. The age- and sex-adjusted incidence of CSDH surgery increased by 30% (IRR 1.30, 95% CI 1.20-1.41). The age- and sex-adjusted incidence increased more in the older age groups, with an IRR of 1.24 for those aged 60-69 years, 1.32 for those 70-79 years, 1.46 for those 80-89 years, and 1.85 for those aged 90 years or older. The adjusted incidence did not increase for those aged 18-59 years. The sex difference (2:1 men/women) was consistent throughout the study period, with a higher incidence among men. One year after the primary surgery, 19% of the population had a resurgery, and the 1-year case fatality rate was 15%. The median age of patients increased from 73 to 76 years. CONCLUSIONS: During the past 2 decades, the age- and sex-adjusted incidence of CSDH surgery has increased in Finland, with major increases for those aged 60 years or older. This increase is likely to continue in parallel with the aging population and increased life expectancies.

Anatomic Risk Factors for S1 Segment Superior Cerebellar Artery Aneurysm Rupture: A Radiologic Study on 81 Consecutive Patients.

BACKGROUND: Due to treatment associated risks, it is still debatable which unruptured aneurysm should be treated. Anatomic and morphologic characteristics may aid to predict the rupture risk of superior cerebellar artery (SCA) aneurysm and possibly support in decision- making during treatment. OBJECTIVES: To identify morphologic characteristics that could predict the rupture of SCA aneurysms. METHODS: A retrospective analysis of computed tomography angiography images of 81 consecutive patients harboring SCA aneurysm who were treated between 1980 to 2014 at Helsinki University Hospital was performed. RESULTS: Of the 81 analyzed SCA aneurysms, 30 (37%) were unruptured and remaining 51 (63%) presented with subarachnoid hemorrhage. The mean ± SD size of unruptured SCA aneurysms was 6.2 ± 6.3 mm; mean size of ruptured SCA aneurysms was 5.9 ± 5.4 mm. The mean ± SD aspect ratio was 0.9 ± 0.3 in unruptured and 1.14 ± 0.44 in ruptured SCA aneurysms. The mean ± SD degree angle between basilar artery and aneurysm was 74.7 ± 24.4 in unruptured and 65.9 ± 23 ruptured SCA aneurysms. Patients with ruptured SCA aneurysm showed significantly higher aspect ratio (Mann-Whitney U, P = 0.01) and smaller aneurysm to basilar artery angle (Mann-Whitney U, P = 0.039). Aspect ratio >1.1 had 2.3 times higher risk of rupture (odds ration [OR] 2.3, 95% confidence interval [CI] 0.84-6.34). An aneurysm to basilar angle <70 degrees had 2.8 times higher risk of rupture (OR 2.75, 95% CI 1.086-6.96). CONCLUSIONS: Ruptured SCA aneurysms are usually small in size. Higher aspect ratio and smaller angle between SCA aneurysm and basilar artery had significantly higher risk of SCA (S1 segment) aneurysm rupture.

Preoperative Magnetic Resonance Image Quality in Motion Disorder Patients Scheduled for Deep Brain Stimulation Surgery.

BACKGROUND: To obtain magnetic resonance (MR) images of good quality for accurate target localization in deep brain stimulation (DBS) surgery, sedation or anesthesia may be used, although their usefulness has not been proven. OBJECTIVE: To assess whether sedation or general anesthesia (GA) improve the quality of MR imaging (MRI). METHODS: The records of DBS procedures for Parkinson's disease (PD), dystonia, and essential tremor in our tertiary neurosurgical unit between January 2011 and June 2016 were reviewed. Adult patients with preoperative MR images were included. Patient records concerning MRI, surgery, adverse events, and clinical outcome were retrospectively scrutinized and analyzed. MR image quality was assessed by two independent radiologists. RESULTS: A total of 215 preoperative MR images for 177 DBS procedures were analyzed. The MRI sequences performed under GA were superior to those performed without anesthesia or under sedation (p < 0.01). Virtually all images captured under GA were of good quality, while the proportions among those captured with sedation or without anesthesia were <65%. Good image quality was not associated with better clinical outcome (>50% improvement in the Unified Parkinson's Disease Rating Scale III score) among patients with PD. CONCLUSION: GA was associated with better MRI sequences than intravenous sedation or no anesthesia.

Intensive care of traumatic brain injury and aneurysmal subarachnoid hemorrhage in Helsinki during the Covid-19 pandemic.

BACKGROUND: To ensure adequate intensive care unit (ICU) capacity for SARS-CoV-2 patients, elective neurosurgery and neurosurgical ICU capacity were reduced. Further, the Finnish government enforced strict restrictions to reduce the spread. Our objective was to assess changes in ICU admissions and prognosis of traumatic brain injury (TBI) and aneurysmal subarachnoid hemorrhage (SAH) during the Covid-19 pandemic. METHODS: Retrospective review of all consecutive patients with TBI and aneurysmal SAH admitted to the neurosurgical ICU in Helsinki from January to May of 2019 and the same months of 2020. The pre-pandemic time was defined as weeks 1-11, and the pandemic time was defined as weeks 12-22. The number of admissions and standardized mortality rates (SMRs) were compared to assess the effect of the Covid-19 pandemic on these. Standardized mortality rates were adjusted for case mix. RESULTS: Two hundred twenty-four patients were included (TBI n = 123, SAH n = 101). There were no notable differences in case mix between TBI and SAH patients admitted during the Covid-19 pandemic compared with before the pandemic. No notable difference in TBI or SAH ICU admissions during the pandemic was noted in comparison with early 2020 or 2019. SMRs were no higher during the pandemic than before. CONCLUSION: In the area of Helsinki, Finland, there were no changes in the number of ICU admissions or in prognosis of patients with TBI or SAH during the Covid-19 pandemic.

Finnish study of intraoperative irrigation versus drain alone after evacuation of chronic subdural haematoma (FINISH): a study protocol for a multicentre randomised controlled trial.

INTRODUCTION: Chronic subdural haematomas (CSDHs) are one of the most common neurosurgical conditions. The goal of surgery is to alleviate symptoms and minimise the risk of symptomatic recurrences. In the past, reoperation rates as high as 20%-30% were described for CSDH recurrences. However, following the introduction of subdural drainage, reoperation rates dropped to approximately 10%. The standard surgical technique includes burr-hole craniostomy, followed by intraoperative irrigation and placement of subdural drainage. Yet, the role of intraoperative irrigation has not been established. If there is no difference in recurrence rates between intraoperative irrigation and no irrigation, CSDH surgery could be carried out faster and more safely by omitting the step of irrigation. The aim of this multicentre randomised controlled trial is to study whether no intraoperative irrigation and subdural drainage results in non-inferior outcome compared with intraoperative irrigation and subdural drainage following burr-hole craniostomy of CSDH. METHODS AND ANALYSIS: This is a prospective, randomised, controlled, parallel group, non-inferiority multicentre trial comparing single burr-hole evacuation of CSDH with intraoperative irrigation and evacuation of CSDH without irrigation. In both groups, a passive subdural drain is used for 48 hours as a standard of treatment. The primary outcome is symptomatic CSDH recurrence requiring reoperation within 6 months. The predefined non-inferiority margin for the primary outcome is 7.5%. To achieve a 2.5% level of significance and 80% power, we will randomise 270 patients per group. Secondary outcomes include modified Rankin Scale, rate of mortality, duration of operation, length of hospital stay, adverse events and change in volume of CSDH. ETHICS AND DISSEMINATION: The study was approved by the institutional review board of the Helsinki and Uusimaa Hospital District (HUS/3035/2019 §238) and duly registered at ClinicalTrials.gov. We will disseminate the findings of this study through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT04203550.

Flow diversion for internal carotid artery aneurysms: Impact of complex aneurysm features and overview of outcome.

OBJECTIVE: Flow diversion is a popular technique used to treat ordinary small, as well as complex internal carotid artery (ICA) aneurysms. We describe aneurysm occlusion rates, complications and patient outcomes in patients with ICA aneurysms treated with flow diverter stents. PATIENTS AND METHODS: We identified all consecutive patients with ICA aneurysms that were treated with flow diverter stents between 2014 and 2019 at our institution. We divided the aneurysms into two anatomic subgroups (cavernous and supraclinoid segments). All the imaging studies and medical records were reviewed for relevant features in relation to aneurysms, complications and patient outcomes. RESULTS: A total of 62 patients with 76 ICA aneurysms (72 unruptured; 4 ruptured) were treated with 70 flow diversion procedures, including six re-treatments. Complete aneurysm occlusion was achieved in 61 % of patients at 6-month follow-up (cavernous 69 %, supraclinoid 58 %), and in 69 % at the latest follow-up (mean of 18 months). Postprocedural intracranial ischemia or hemorrhage was seen in 24 % of patients, including two aneurysm ruptures after flow diversion, and related major long-term functional decline or mortality was seen in 6% of patients. Preprocedural dysfunction of extraocular muscles or vision disturbance improved moderately at best (40-60 %). At the latest follow-up, 54 patients (87 %) were functionally independent (mRS ≤2). CONCLUSION: Flow diversion for cavernous and supraclinoid ICA aneurysms demonstrated acceptable results, but complex aneurysm features cause uncertainty in predicting aneurysm occlusion probability. Patients should be informed of the non-negligible rate of complications, and of only moderate improvement rate of cranial nerve dysfunctions.

Transition of a Clinical Practice to Use of Subdural Drains after Burr Hole Evacuation of Chronic Subdural Hematoma: The Helsinki Experience.

BACKGROUND: A number of randomized controlled trials have shown the benefit of drain placement in the operative treatment of chronic subdural hematoma (CSDH); however, few reports have described real-life results after adoption of drain placement into clinical practice. We report the results following a change in practice at Helsinki University Hospital from no drain to subdural drain (SD) placement after burr hole craniostomy for CSDH. METHODS: We conducted a retrospective observational study of consecutive patients undergoing burr hole craniostomy for CSDH. We compared outcomes between a 6-month period when SD placement was arbitrary (July-December 2015) and a period when SD placement for 48 hours was routine (July-December 2017). Our primary outcome of interest was recurrence of CSDH necessitating reoperation within 6 months. Patient outcomes, infections, and other complications were assessed as well. RESULTS: A total of 161 patients were included, comprising 71 (44%) in the drain group and 90 (56%) in the non-drain group. There were no significant differences in age, comorbidities, history of trauma, or use of antithrombotic agents between the 2 groups (P > 0.05 for all). Recurrence within 6 months occurred in 18% of patients in the non-drain group, compared with 6% in the drain group (odds ratio, 0.28; 95% confidence interval, 0.09-0.87; P = 0.028). There were no differences in neurologic outcomes (P = 0.72), mortality (P = 0.55), infection rate (P = 0.96), or other complications (P = 0.20). CONCLUSIONS: The change in practice from no drain to use of an SD after burr hole craniostomy for CSDH effectively reduced the 6-month recurrence rate with no effect on patient outcomes, infections, or other complications.

Bypass Surgery for Complex Internal Carotid Artery Aneurysms: 39 Consecutive Patients.

OBJECTIVE: Bypass surgery is a special technique used to treat complex internal carotid artery (ICA) aneurysms. The aim of this retrospective study is to provide a comprehensive description of treatment and outcome of complex ICA aneurysms at different ICA segments (cavernous, supraclinoid, ICA bifurcation) treated with bypass procedures. METHODS: We identified 39 consecutive patients with 41 complex ICA aneurysms that were treated with 44 bypass procedures between 1998 and 2016. We divided the aneurysms into 3 anatomic subgroups to review our treatment strategy. All the imaging studies and medical records were reviewed for relevant information. RESULTS: The aneurysm occlusion (n = 34, 83%) or flow modification (n = 5, 12%) was achieved in 39 aneurysms (95%). The long-term bypass patency rate was 68% (n = 30). Minor postoperative ischemia or hemorrhage was commonly seen (n = 20, 51%), but large-scale strokes were rare (n = 1, 3%). Preoperative dysfunction of extraocular muscles (cranial nerves III, IV, and VI) showed low-to-moderate improvement rates (20%-50%). Preoperative vision disturbance (cranial nerve II) improved seldom (22%). At the latest follow-up (mean; 51 months) 29 patients (74%) were independent (modified Rankin Scale ≤2). CONCLUSIONS: Bypass surgery for complex ICA aneurysms is a feasible treatment method with an acceptable risk profile. Patients should be informed of the uncertainty related to improvement of pretreatment cranial nerve dysfunctions.

The focus of temperature monitoring with zero-heat-flux technology (3M Bair-Hugger): a clinical study with patients undergoing craniotomy.

In the noninvasive zero-heat-flux (ZHF) method, deep body temperature is brought to the skin surface when an insulated temperature probe with servo-controlled heating on the skin creates a region of ZHF from the core to the skin. The sensor of the commercial Bair-Hugger ZHF device is placed on the forehead. According to the manufacturer, the sensor reaches a depth of 1-2 cm below the skin. In this observational study, the anatomical focus of the Bair-Hugger ZHF sensor was assessed in pre- and postoperative CT or MRI images of 29 patients undergoing elective craniotomy. Assuming the 2-cm depth from the forehead skin surface, the temperature measurement point preoperatively reached the brain cortex in all except one patient. Assuming the 1-cm depth, the preoperative temperature measurement point did not reach the brain parenchyma in any of the patients and was at the cortical surface in two patients. Corresponding results were obtained postoperatively, although either sub-arachnoid fluid or air was observed in all CT/MRI images. Craniotomy did not have a detectable effect on the course of the ZHF temperatures. In Bland-Altman analysis, the agreement of ZHF temperature with the nasopharyngeal temperature was 0.11 (95% confidence interval - 0.54 to 0.75) °C and with the bladder temperature - 0.14 (- 0.81 to 0.52) °C. As conclusions, within the reported range of the Bair-Hugger ZHF measurement depth, the anatomical focus of the sensor cannot be determined. Craniotomy did not have a detectable effect on the course of the ZHF temperatures that showed good agreement with the nasopharyngeal and bladder temperatures.

Riskier-than-expected occlusive treatment of ruptured posterior communicating artery aneurysms: treatment and outcome of 620 consecutive patients.

OBJECTIVE: Occlusive treatment of posterior communicating artery (PCoA) aneurysms has been seen as a fairly uncomplicated procedure. The objective here was to determine the radiological and clinical outcome of patients after PCoA aneurysm rupture and treatment and to evaluate the risk factors for impaired outcome. METHODS: In a retrospective clinical follow-up study, data were collected from 620 consecutive patients who had been treated for ruptured PCoA aneurysms at a single center between 1980 and 2014. The follow-up was a minimum of 1 year after treatment or until death. RESULTS: Of the 620 patients, 83% were treated with microsurgical clipping, 8% with endovascular coiling, 2% with the two procedures combined, 1% with indirect surgical methods, and 6% with conservative methods. The most common procedural complications were treatment-related brain infarctions (15%). The occurrence of artery occlusions (10% microsurgical, 8% endovascular) was higher than expected. Most patients made a good recovery at 1 year after aneurysmal subarachnoid hemorrhage (modified Rankin Scale [mRS] score 0-2: 386 patients [62%]). A fairly small proportion of patients were left severely disabled (mRS score 4-5: 27 patients [4%]). Among all patients, 20% died during the 1st year. Independent risk factors for an unfavorable outcome, according to the multivariable analysis, were poor preoperative clinical condition, intracerebral or subdural hematoma due to aneurysm rupture, age over 65 years, artery occlusion on postoperative angiography, occlusive treatment-related ischemia, delayed cerebral vasospasm, and hydrocephalus requiring a shunt. CONCLUSIONS: Even though most patients made a good recovery after PCoA aneurysm rupture and treatment during the 1st year, the occlusive treatment-related complications were higher than expected and caused morbidity even among initially good-grade patients. Occlusive treatment of ruptured PCoA aneurysms seems to be a high-risk procedure, even in a high-volume neurovascular center.