Browsing by Subject "neurosurgery"
Now showing items 1-8 of 8
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(2018)Background: Identification and anatomic features of the feeding arteries of the arteriovenous malformations (AVMs) is very important due to neurologic, radiologic, and surgical reasons. Materials and methods: Seventy-seven patients with AVMs were examined by using a digital subtraction angiographic (DSA) and computerised tomographic (CT) examination, including three-dimensional reconstruction of the brain vessels. In addition, the arteries of 4 human brain stems and 8 cerebral hemispheres were microdissected. Results: The anatomic examination showed a sporadic hypoplasia, hyperplasia, early bifurcation and duplication of certain cerebral arteries. The perforating arteries varied from 1 to 8 in number. The features of the leptomeningeal and choroidal vessels were presented. The radiologic examination revealed singular (22.08%), double (32.48%) or multiple primary feeding arteries (45.45%), which were dilated and elongated in 58.44% of the patients. The feeders most often originated from the middle cerebral artery (MCA; (23.38%), less frequently from the anterior cerebral artery (ACA; 12.99%), and the posterior cerebral artery (PCA; 10.39%). Multiple feeders commonly originated from the ACA and MCA (11.69%), the MCA and PCA (10.39%), the ACA and PCA (7.79%), and the ACA, MCA and PCA (5.19%). The infratentorial feeders were found in 9.1% of the AVMs. Contribution from the middle meningeal and occipital arteries was seen in 3.9% angiograms. Two cerebral arteries had a saccular aneurysm. The AVM haemorrhage appeared in 63.6% of patients. Conclusions: The knowledge of the origin and anatomic features of the AVMs feeders is important in the explanation of neurologic signs, and in a decision regarding the endovascular embolisation, neurosurgical and radiosurgical treatments.
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(2018)Background:Albumin and mannitol may interfere with hemostasis, but their coinfluence is unclear. We aimed to determine the effects of albumin alone and in combination with mannitol or Ringer acetate (RAC) on hemostasis in crossover in vitro study.Materials and Methods:From citrated fresh whole blood withdrawn from 10 volunteers, we prepared 2.5, 5, 10, 15, and 20 vol% dilutions of 4% albumin (Alb group). Each sample was thereafter diluted by 15% mannitol (Alb/Man group) or RAC (Alb/RAC group) at a ratio of 9:1. Using thromboelastometry, FibTEM (fibrinogen ROTEM) and ExTEM (extrinsic ROTEM) tests were performed.Results:A 20 vol%, but not 2.5 to 15 vol% dilution of albumin caused a prolonged clot formation time, -angle decrease, and maximum clot firmness (MCF) weakening compared with undiluted sample (P
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(2018)A system for assisting in microneurosurgical training and for delivering interactive mixed reality surgical experience live was developed and experimented in hospital premises. An interactive experience from the neurosurgical operating theater was presented together with associated medical content on virtual reality eyewear of remote users. Details of the stereoscopic 360-degree capture, surgery imaging equipment, signal delivery, and display systems are presented, and the presence experience and the visual quality questionnaire results are discussed. The users reported positive scores on the questionnaire on topics related to the user experience achieved in the trial.
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(Helsingin yliopisto, 2020)Immediate and long-term outcomes after treating patients with pineal region cysts and tumors are not well established. The centralized Finnish health care and the Finnish population register offer excellent registry systems for long-term retrospective studies. This thesis aimed to investigate the long-term outcomes of surgically treated pineal region cysts and tumors based on three elements developed in Helsinki University Hospital along the study period: a. the complete microsurgical resection; b. the praying sitting position, and c. the paramedian supracerebellar infratentorial approach. Pineal region neoplasms are well-recognized entities. However, quantitative parameters to differentiate normal anatomical variations from pathological benign pineal cysts are currently inexistent. Thus, we studied the correlation between the pineal cyst size and the clinical severity of the patients. This thesis presents one of the most comprehensive long-term studies of surgically treated pineal region cysts and tumors. The long-term survival, clinical, and radiological outcomes present here were superior to those reported in the literature. Each publication includes a subgroup of the 147 consecutive surgically treated patients with pineal region lesions operated in the Department of Neurosurgery of Helsinki University Hospital between 1997 and 2015. We found a direct correlation between the pineal cyst diameters and the severity of the disease. Thus, a surgically treated pineal cyst appeared a clinically progressive disease with average cyst diameters running between 15mm and 25mm and hydrocephalus at the last stage. The short- and long-term postoperative functional status of the pineal cyst patients improved after surgery in all except one patient. 97% of the pineal cyst patients achieved complete cyst removal without noticed recurrence nor mortality at 149 ± 62 months. The disease mortality of the patients with surgically treated pineal region tumors reached 18% at 125 ± 105 months of follow-up. Overall, patients with complete tumor removal had superior disease survival and tumor-free imaging outcomes compared to those with incomplete resected neoplasms. However, the extent of resection did not appear to influence the survival rates of diffuse glioma patients. Venous air embolism was present in 35% of patients undergoing praying sitting position for pineal region surgery. Severe venous air embolism was absent in the studied series. Among all pre- and intraoperative variables, the only venous injury was associated with venous air embolism. Thus, following proper anesthetic and surgical considerations, the sitting praying position in pineal region surgery does not harbor high risks for severe venous air embolism. Lately, the developed paramedian approach resulted in more functional and safer modification of the conventional midline supracerebellar approach. The effectiveness of the two approaches remained similar in terms of clinical, radiological, and survival outcomes.
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(Helsingin yliopisto, 2016)Objective: Aneurysms of the posterior cerebral artery are rare vascular lesions. The overall incidence is less than 1%, representing around 7% of posterior circulation aneurysms. Due to this low incidence, most of the institutional series on PCA aneurysms are small and contain less than 25 patients. Only one other series comparable in scope to ours has been previously published. The presented study analyzes and describes the characteristic features of PCA aneurysms as well as investigates the relevant treatment strategies and their outcomes. A particular focus is in the description and analysis of PCA aneurysms treated from a subtemporal approach and the pres - entation of an associated aneurysm treatment from a lateral supraorbital approach. Patients and Methods: We reviewed 121 patients diagnosed with 135 PCA aneurysms, all of whom were treated between 1980 and 2012 at two Finnish neurosurgical units (Department of Neurosurgery at the University of Eastern Finland, Kuopio and Department of Neurosurgery at the University of Helsinki). Additionally, twelve historical (pre-1980) cases were presented. Detailed analyses of cerebral angiographies were conducted for 93 PCA aneurysms in 81 patients. A further subgroup analysis of 34 patients diagnosed with 37 PCA aneurysms treated via subtemporal approach was also performed. Results: Of the 121 patients with 135 PCA aneurysms, 52 (39%) aneurysms were ruptured and 83 (61%) unruptured . The following distribution along the PCA segments was observed: P1 segment (n=53), P1/2 junction (n=39), P2 segment (n=28), and P3 segment (n=15); no P4 segment aneurysms were found. Saccular aneurysms were more common than fusiform PCA aneurysms (76% vs. 24%). The detailed angiographic analysis showed that the median aneurysm size was 7 mm for ruptured PCA aneurysms and 4 mm for unruptured aneurysms. Saccular aneurysms (n=69, 74%) had a characteristic dome projection for each location: P1 segment, upward (67%); P1/P2 junction, anterior/upward (80%); P2 segment, lateral (67%); and P3 segment, posterior (50%). The following treatment results at 1-year follow-up were achieved for patients with: unruptured PCA aneurysms (n=19; 12 good outcomes, 63%; 6 moderate, 31%; 1 poor, 5%), ruptured PCA aneurysms (n=27; 10 good, 37%; 9 moderate, 33%; 8 poor, 30%), and patients with complex neurovascular pathologies and PCA aneurysms (n=96; 42 good, 43%; 40 moderate, 42%; 14 poor, 15%). Analyzing the subtemporal approach we found that most complications were not related to the subtemporal approach itself but to the specific nature of the PCA aneurysms treated and the chosen strategy. The most common (12 out of 34; 35%) serious complication in this series was an ipsilateral PCA infarction after parent vessel occlusion. Conclusion: PCA aneurysms are infrequent vascular lesions that are often associated with other vascular pathologies. Most ruptured PCA aneurysms are smaller than 10 mm and distally located. The saccular PCA aneurysms have a typical dome orientation at each PCA segment. Microsurgery and endovascular treatment are effective options for the occlusion of PCA aneurysms. As a result, individual treatment strategies are required. Despite commonly adequate vessel collateralization of the distal PCA territory, preservation or reconstruction of the parent vessel is crucial for favorable treatment outcomes. The subtemporal approach is favorable for the treatment of PCA aneurysms in proximity to the tentorium. Frontolateral approaches allow the treatment of proximal PCA aneurysms and ipsilateral anterior circulation aneurysms inside the Circle of Willis.
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(Helsingin yliopisto, 2014)Background and objectives The middle cerebral artery (MCA) is the most frequent location of unruptured intracranial aneurysms (IAs). The rupture of IAs causes subarachnoid hemorrhaging (SAH) with high rates of morbidity and mortality. However, controversy remains regarding which unruptured MCA aneurysms should be prophylactically treated since treatment is not without risks. More insight when deciding upon the management of MCA aneurysms and less risky treatment options are still needed. Nevertheless, MCA aneurysms are typically classified according to their location in relation to the main MCA bifurcation despite the inconsistent and subjective nature of identifying this main branching point. This study aimed to objectively characterize the main MCA bifurcation as a key factor for the more accurate classification of MCA aneurysms (publication I), to statistically identify the topographical and morphological characteristics of MCA aneurysms which could predict an increased risk of rupture (publication II) and to technically minimize the invasiveness of the microsurgical treatment of MCA aneurysms (publication III). Methods Computerized tomography angiography (CTA) data from 1,009 consecutive patients with 1,309 MCA aneurysms constituted the basis of this study. The angiographic definition of the MCA main bifurcation (Mbif) as the starting point of the insular trunks (M2s) was the basis of its objective characterization (publication I). The morphological and topographical characteristics of MCA aneurysms were examined and compared to the aneurysm rupture status; then, univariate and multivariate logistic regression analysis were performed to determine the independent risk factors for rupture (publication II). Moreover, based on the surgical experience of Professor Juha Hernesniemi, we presented the basics principles and techniques for safely clipping MCA aneurysms through a 10 15-mm focused opening of the sylvian fissure (publication III). Results The 1,309 MCA aneurysms were classified after objectively determining the Mbif, which was the most common location for MCA aneurysms harboring 829 (63%) aneurysms. The 406 proximal middle cerebral artery (M1) aneurysms comprised 242 (60%) aneurysms at the origin of the early cortical branches (M1 ECBAs) and 164 (40%) aneurysms at the origin of the lenticulostriate arteries (M1 LSAAs). There were only 74 (6%) aneurysms distal to the Mbif. At the time of presentation, more than two-thirds of the MCA aneurysms (69%) were unruptured and 31% were ruptured. Most unruptured MCA aneurysms had a size less than 7 mm (78%), a smooth wall (80%), a height width ratio = 1 (47%) and were located at the main bifurcation (57%). Ruptured MCA aneurysms were primarily sized 7 14 mm (55%), had an irregular wall (78%), a height width ratio more than 1 (72%) and were located at the main bifurcation (77%). In addition, 38% of MCA bifurcation aneurysms, 74% of large aneurysms, 64% of aneurysms with an irregular wall and 49% of aneurysms with a height width ratio more than 1 were ruptured. In our experience, the focused sylvian opening technique for the microsurgical management of MCA aneurysms resulted in shorter operative times and less inadvertent brain and vessel manipulation. Thus, it proved to be safe and effective for the clipping of both ruptured and unruptured MCA aneurysms. Conclusions Image-based analysis of the angioarchitecture of MCA can objectively define the main MCA bifurcation and helps in classifying MCA aneurysms more accurately. The analysis of topographical and morphological characteristics of MCA aneurysms is important when deciding upon their management, where their location at the main MCA bifurcation, the wall irregularity and a less spherical geometry equate to an increased risk of rupture. Thus, the focused opening of the sylvian fissure is a practical, less invasive alternative to the classical wide sylvian opening for the microsurgical management of most MCA aneurysms.
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(2017)Background: Neurosurgeons devoted to bypass neurosurgery or revascularization neurosurgery are becoming scarcer. From a practical point of view, 'bypass neurosurgeons' are anastomosis makers, vessels technicians, and time-racing repairers of vessel walls. This requires understanding the key features and hidden tricks of bypass surgery. The goal of this paper is to provide simple and inexpensive tricks for taming the art of bypass neurosurgery. Most of these tricks and materials described can be borrowed, donated, or purchased inexpensively. Methods: We performed a review of relevant training materials and recorded videos for training bypass procedures for 3 years between June 2014 and July 2017. In total, 1,300 training bypass procedures were performed, of which 200 procedures were chosen for this paper. Results : A training laboratory bypass procedures is required to enable a neurosurgeon to develop the necessary skills. The important skills for training bypass procedures gained through meticulous practice to be as reflexes are coordination, speed, agility, flexibility, and reaction time. Bypassing requires synchronization between the surgeon's gross movements, fine motoric skills, and mental strength. The suturing rhythm must be timed in a brain-body-hand fashion. Conclusion: Bypass-Training is a critical part of neurosurgical training and not for a selected few. Diligent and meticulous training can enable every neurosurgeon to tame the art of bypass neurosurgery. This requires understanding the key features and hidden tricks of bypass surgery, as well as uncountable hours of training. In bypass neurosurgery, quality and time goes hand in hand. © 2017 Surgical Neurology International | Published by Wolters Kluwer - Medknow.
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(Helsingin yliopisto, 2019)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.
