Surgical Treatment Of Cerebral Aneurysms Research Articles

EXPERT AND CLINICAL ASSESSMENT OF DEFICIENCIES IN PROVIDING CARE TO PATIENTS WITH TRAUMATIC BRAIN INJURY AND HEMORRHAGIC STROKE DUE TO THE RUPTURE OF CEREBRAL ANEURYSM

Introduction. The relevance of conducting this study is determined by the necessity to create organizational conditions and optimize the clinical-diagnostic aspect of medical care for patients with traumatic brain injury (TBI) and acute stroke. This aims to improve patients' quality of life by enhancing the effectiveness of medical care provision in Ukraine. This improvement is based on identifying the causes and analyzing deficiencies in medical care for these conditions.
 The aim of the research is to investigate the specificity of deficiencies in providing medical care to patients with isolated traumatic brain injury and acute hemorrhagic stroke due to the rupture of cerebral arterial aneurysms based on a retrospective analysis of medical documentation, as well as the results of patient treatment in cases of discrepancies between clinical and forensic diagnoses concerning the primary, concomitant diseases, and their complications.
 Materials and methods. Clinical assessment of the results of providing care to patients with traumatic brain injury and stroke was conducted through a retrospective analysis of medical documentation of patients who were hospitalized with these pathologies. The applied methods include clinical and laboratory investigations of homeostasis and metabolism parameters, and instrumental techniques.
 Results. In the identified influence of the timing of the operation (within the first few days) and the breakthrough of blood in the subarachnoid space of the brain, including with intracranial hemorrhage as a result of a re-rupture of a cerebral arterial aneurysm, on the risk of lethal outcomes of surgical treatment, a rationale for searching ways to optimize therapeutic tactics in this category of patients was provided. This includes identifying defects and shortcomings in the organizational aspect of medical care.
 Conclusions. Based on the analysis and identification of the most informative factors influencing the results of surgical treatment of cerebral aneurysms, a prediction system has been developed that allows calculating the probability of its outcome. The application of the forecast is advisable to consider in the prevention and timely detection of possible deficiencies in providing medical care to patients with stroke.

Computed tomography, functional and cognitive changes in the long-time period of surgery of cerebral aneurysms

Assessment of patients with intracranial aneurysms in the late postoperative period consists of both determining structural changes in computed tomography (CT) and the neurological and cognitive status of the patient. Meantime, the topic of the relationship between structural pathology in CT and cognitive impairment has not been suffi ciently disclosed. Objective: to determine CT, functional and cognitive outcomes in the long-term period of surgical treatment of cerebral aneurysms. Material and methods. The data of CT angiography of 49 patients operated on for intracranial aneurysms were analyzed. 39 patients were examined neurologically for 2.3 years using a range of rating scales. Results. The residual part of the aneurysm after surgery was found in 50% of patients with complex aneurysms, more often in patients with PMA-PSA aneurysms. The connection between the method of surgery and the preserved cervical part with structural changes in the brain and the development of cognitive impairment in the late postoperative period has not been proven. Conclusion. CT angiography preoperatively makes it possible to identify a group of complex aneurysms with a high risk of preservation of the cervical part and the development of brain structural changes. The predictors of the development of ischemic changes in the brain, hydrocephalus, and cognitive dysfunctions was the advanced age of patients, the duration of the operation, and a history of hypertension.

Long-term results of surgical treatment of patients with cerebral arterial aneurysms

To study the long-term results of surgical treatment of patients operated on for cerebral aneurysms and their impact on functional recovery, independence and cognitive functions in the long-term period. A multivariate regression analysis of long-term results of surgical treatment of 324 patients for cerebral aneurysms was performed (on average after 3.5 years). Upon admission of the patient to the hospital for surgical intervention, a clinical diagnostic examination was performed to confirm the diagnosis and determine the volume, timing and type of intervention. In the late period, a clinical neurological study was performed, which included an assessment of the degree of disability with the Barthel index and a modified Rankin scale, cognitive functions with MMSE, and the mental sphere with HADS. The severity of the condition at admission, corresponding to grade III-IV according to the Hunt-Hess classification, was the risk factor for an unfavorable prognosis for the recovery of patients in the long-term period of cerebral aneurysm surgery. The severe condition of patients at the onset of the disease increases the risk of disability by 1.9 times (p<0.05) and the risk of dementia by 6 times (p<0.05). An independent risk factor for the development of cognitive impairment is the patient's age: with an increase in age by 1 year, the MMSE score decreases by 0.27 (p<0.05). The prevalence of hemorrhage according to the Fisher classification, corresponding to grade III, is a predictor of the development of angiospasm in 91% of cases. In patients with established angiospasm, the risk of developing dementia and pre-dementia cognitive impairment was 57.3% (p<0.05). The best predictions for recovery of cognitive functions in the long-term period were observed in patients who underwent simultaneous aneurysm clipping with extra-intracranial anastomosis (mean MMSE score 25) compared with patients who underwent only aneurysm clipping (mean score 20), endovascular intervention (average score 21) or microsurgical intervention followed by intrathecal fibrinolytic injection (mean MMSE score of 20) (p<0.05). The predictors of unfavorable recovery of cognitive functions and the development of disability in the long-term period of surgical treatment of cerebral aneurysms were the severity of the condition at admission, corresponding to III-IV st. according to the Hunt-Hess classification, the age of the patient at the time of the intervention, the prevalence of hemorrhage according to Fisher, and the choice of surgical technique.

Surgical revascularization (bypass surgery) in the treatment of complicated cerebral aneurysms

The aim of surgical treatment of any cerebral aneurysm is to achieve its total exclusion from the bloodstream. Although the progress in the development and implementation of microsurgical and the latest endovascular technologies, in many cases, the treatment of complex cerebral aneurysms is not an easy task. Unsatisfactory results of the exclusion of complicated cerebral aneurysms are due to many factors, for instance: gigantic size, fusiform or dolichoectatic configuration of the cerebral aneurysm, the presence of atherosclerotic changes, anatomical features of the departure of functionally important arteries directly from the cerebral aneurysm. Such cerebral aneurysms are quite problematic both for microsurgical remodeling clipping and for endovascular exclusion. At the current stage, the introduction and use of the microanastomosis technique provides additional options and expands the possibilities of surgical treatment of complex cerebral aneurysms.Objective ‒ to analyze the possibilities and results of surgical treatment of complicated cerebral aneurysms using the technique of surgical revascularization (bypass surgery).Materials and methods. An analysis of the results of the examination and surgical treatment of 16 patients with complicated cerebral aneurysms for the period from 2016 to 2020, who were treated and operated on in the emergency vascular neurosurgery department with the X-ray operating department Romodanov Institute of Neurosurgery of NAMS of Ukraine. All patients diagnosed with complicated cerebral aneurysms had gigantic sizes. All cases of surgical intervention included placement of extra-intracranial microanastomosis or intra-intracranial anastomosis, sometimes a combination of it, to ensure normal blood supply to the vessel of complicated cerebral aneurysm that were planned to be devascularized. In 14 observations, one-time anastomosis and exclusion of complicated cerebral aneurysms were performed. In 2 observations, the first stage was an anastomosis without exclusion of the complicated cerebral aneurysms due to insufficient vascularization of the distal arterial branch for deconstructive exclusion of aneurysm.Results. Satisfactory results of surgical treatment (grade 1 and 2 of Modified Rankin Scale (MRS)) in the general group of patients were observed in 13 (81 %) patients with complicated cerebral aneurysms. Unsatisfactory results of surgical treatment occurred in 3 (19 %) observations. Profound disability (MRS grade 5) as a result of surgical treatment was recorded in 1 (6 %) patient. Cases that ended fatally occurred in 2 (13 %) observations of the total group of patients. In the group of patients with surgical revascularization and excluded complicated cerebral aneurysms, satisfactory results were observed in 13 (92.9 %) patients. Fatal results of surgical treatment were recorded in 2 patients with a hemorrhagic course of complicated cerebral aneurysms, in which surgical revascularization was performed as first stage and scheduled removal of complicated cerebral aneurysms was planned.Conclusions. The introduction and use of the microanastomosis technique expands the possibilities of surgical treatment of complicated cerebral aneurysms. Revascularization surgical interventions are highly effective in the prevention of ischemic complications when complicated cerebral aneurysms are excluded. Recommendations (indications) for revascularization should be considered in impossibility and high risks of ischemic complications during remodeling clipping or endovascular exclusion of complicated cerebral aneurysms.

Intraoperative Angiogram Using C-Arm Fluoroscopy and Direct Common Carotid Artery Puncture During Surgical Treatment of Paraclinoid Aneurysms

Intraoperative angiography (IOA) has been shown to be a useful adjunct in surgical treatment of cerebral aneurysms. However, its use can be limited by hybrid operating room availability. On the other hand, the use of C-arm fluoroscopy can add challenges to IOA during navigation of the aortic arch and selection of the great vessels. We aimed to describe a simple method of IOA that can be applied during surgery of paraclinoid aneurysms and can be performed in a normal operating room without the need to navigate the aortic arch. In patients undergoing surgery for paraclinoid aneurysms with need for cervical carotid artery exposure, IOA was performed using a single plane C-arm fluoroscopy unit after direct puncture of the carotid artery. Five patients were included: 2 with subarachnoid hemorrhage, 2 with unruptured aneurysm and history of subarachnoid hemorrhage, and 1 with unruptured aneurysm. There were 2 internal carotid blister aneurysms, 2 ophthalmic artery aneurysms, and 1 superior hypophyseal artery aneurysm. IOA was performed using direct carotid puncture through the neck incision required for proximal control. In all cases, intraoperative images were of sufficient quality to determine the completeness of aneurysm occlusion as well as parent and branching vessel patency. There were no postoperative infarctions and no complications related to IOA. IOA using direct carotid puncture can be performed in a standard operating room with the use of a C-arm, eliminating the need to catheterize the great vessels of the aortic arch.

Avoiding Complications in Aneurysm Ligation: Operative Tips and Tricks

Preventing possible complications during brain aneurysm surgery is mandatory to ensure a better outcome for patients. Currently, it is possible to rely on some technologic innovations such as motor evoked potential, endoscope-assisted surgery, dye with indocyanine green, and video angiography capable of supporting the surgeon's work. The innovation process has mainly assisted the endovascular technique compared with surgery. The latter, apart from some new technical expedients, always requires anatomic knowledge and optimal technical preparation. A careful patient selection, adequate surgical exposure, use of microsurgical techniques in expert hands, and meticulous postoperative management represent the key to success for the surgical treatment of cerebral aneurysms.

Exploration of the Effect of Clinical Pathway Nursing in the Surgical Treatment of Cerebral Aneurysm

Exploration of the Effect of Clinical Pathway Nursing in the Surgical Treatment of Cerebral Aneurysm

Surgical Treatment of Cerebral Aneurysms in the Acute Period of Subarachnoid Hemorrhage: Long-Term Result

Surgical Treatment of Cerebral Aneurysms in the Acute Period of Subarachnoid Hemorrhage: Long-Term Result

Cerebrovascular aneurysm clipping training models with pulsatile blood flow

Introduction. Neurosurgery trainees are finding it increasingly difficult to obtain operative experience as the main surgeon in aneurysm procedure. Good quality cadaver dissection opportunities are also not widely available for neurosurgery residents. Simulation is emerging as a useful training aid for neurosurgery. Surgical treatment of cerebral aneurysms requires specialized skills development and proficient use of microsurgical instruments. Furthermore, any advance in neurosurgical training methods is of potential value to both neurosurgeons and patients.The study objective is to introduce a 3D aneurysm clipping training model to enhance skill acquisition and development.Materials and methods. The brain model is made using a 3D printed resin mold. The mold is filled with silicone Ecoflex 00–10 and mix with Silc Pig pigment additives to replicate the color and consistency of brain tissue. Dura is made from quick drying silicone paste with grey dye. The blood vessels are made from a silicone 3D printed mold of a magnetic resonance angiography. Liquid with paprika oleoresin (E160c) dye is used to simulate blood and is pumped through the vessels to simulate pulsatile motion.Results and conclusion. These models offer an alternative method to train residents and preoperative planning. They are affordable and easy to recreate and hence can standardize training in multiple centers. With advancing technology, 3D technology is becoming an import part of medical education.

Cognitive functions in patients in the long-term period of microsurgical treatment of cerebral aneurysms

Objective: to study cognitive functions in patients in the long-term period of microsurgical treatment of cerebral aneurysms. Materials methods: on the basis of the University Clinic of the Moscow State Medical University. A.I. Evdokimov and the Department of Emergency Neurosurgery of the N.V. Sklifosovsky Research Institute for Emergency Medicine, an analysis of cognitive functions was carried out in 212 patients operated on by a microsurgical method since 2013. Results: in the long-term period of surgical treatment of cerebral aneurysms, cognitive impairments of varying severity were detected in 78 patients (37 %). The main factors negatively affecting cognitive functions were the severity of the patient’s condition before surgery, corresponding to Hunt-Kosnik III–V, the age of patients over 60 years old, body mass index over 30, localization of the aneurysm in the basin of the anterior cerebral artery and vertebrobasilar basin, patients’ condition discharge according to the Glasgow Grade IV–III Outcome Scale. No significant dependence of cognitive impairment on the severity of subarachnoid hemorrhage and the gender of patients was found. On the contrary, the severity of anxiety and depression, which was assessed on the HADS scale, was twice as likely to be observed in female patients as compared with male patients. Conclusion: it is obvious that the persistence of cognitive deficit and mental disorders, in the form of anxiety and depression, in the long-term period of surgical treatment of cerebral aneurysms dictates the need for long-term dispensary observation and correction of the revealed disorders.

Surgical treatment of cerebral aneurysms in the Russian Federation

The objective of this study was to evaluate the results of surgical treatment of cerebral aneurysms in the Russian Federation. We analyzed performance indicators in neurosurgical departments of regional and federal health institutions of the Russian Federation for 2017. The results of surgical treatment of cerebral aneurysms (CAs) were analyzed in 19 regional vascular centers (RVCs) in several federal districts and in 3 federal centers (FCs) with the most dynamically developing vascular neurosurgery and smoothly running system of statistical data processing. The study included 3160 patients hospitalized to 22 medical institutions in 2017. Of these, 1808 patients were treated in RVCs, and 1352 patients were treated in FCs. We analyzed factors affecting the treatment outcome in CA patients. We identified features of CA treatment in clinics with a different amount of surgical intervention. An increase in the surgical activity in centers and simultaneous development of microsurgical and endovascular treatments for cerebral aneurysms reduce postoperative mortality. Due to the presence of a RVC network in the Russian Federation, many patients could receive necessary specialized treatment. The number of operations for cerebral aneurysms has increased 6-fold for the past 10 years.

Face, Content, and Construct Validity of an Aneurysm Clipping Model Using Human Placenta.

Proficient open surgical treatment of cerebral aneurysms requires extensive training and practice. This study tested the validity of a human placenta aneurysm model for surgical simulation training of aneurysm clipping. There were 30 participants divided into 3 groups (n= 10 per group) according to their neurosurgical experience: low experience, intermediate experience, and attending. Subjective measures were collected using the Aneurysm Clipping Participant Survey (n= 27). Objective measures were collected by observing the participants (n= 30) work through a series of aneurysm clipping tasks while 2 independent raters evaluated them using a newly developed standardized tool, the Objective Structured Assessment of Aneurysm Clipping Skills. In terms of the subjective measures of face validity, most of the attending group (7/10; 70%) rated the models as "somewhat" to "very well" replicating real surgery. Content validity assessment of the model showed that it could improve the following skills: microdissection technique (27/27; 100%), use of clip appliers for aneurysm clipping (27/27; 100%), and surgical technique when applied to patients (25/27; 93%). The objective measure for construct validity demonstrated that mean Objective Structured Assessment of Aneurysm Clipping Skills scores between the 3 groups (low-experience group, 22.9 ± 5.4; intermediate-experience group, 32.8 ± 4.0; attending group, 43.3 ± 1.3) differed significantly (P < 0.001). The human placenta aneurysm clipping model is a useful training tool for teaching residents, with evidence of internal consistency and face, content, and construct validities. The Objective Structured Assessment of Aneurysm Clipping Skills scale is a feasible tool to assess aneurysm clipping skills quantitatively.

Superficial Temporal Artery-Sparing Mini-Pterional Approach for Cerebral Aneurysm Surgery.

ObjectiveThe purposes of this study were to introduce a superficial temporal artery (STA)-sparing mini-pterional approach for the treatment of cerebral aneurysms and review the surgical results of this approach.MethodsBetween June 2010 and December 2015, we performed the STA-sparing mini-pterional approach for 117 patients with 141 unruptured intracranial aneurysms. We analyzed demographic, radiologic, and clinical variables including age, sex, craniotomy size, aneurysm location, height of STA bifurcation, and postoperative complications.ResultsThe mean age of patients was 58.4 years. The height of STA bifurcation from the superior border of the zygomatic arch was 20.5 mm±10.0 (standard deviation [SD]). The craniotomy size was 1051.6 mm2±206.5 (SD). Aneurysm neck clipping was possible in all cases. Intradural anterior clinoidectomy was performed in four cases. Contralateral approaches to aneurysms were adopted for four cases. Surgery-related complications occurred in two cases. Permanent morbidity occurred in one case.ConclusionOur STA-sparing mini-pterional approach for surgical treatment of cerebral aneurysms is easy to learn and has the advantages of small incision, STA sparing, and a relatively wide surgical field. It may be a good alternative to the conventional pterional approach for treating cerebral aneurysms.

Historical Perspective and the Role of Endoscopy in Intracranial Aneurysm Surgery

The surgical treatment of cerebral aneurysms has a relatively recent history, dating to the 1930s, and it is still an evolving field. In 1931, Norman Dott performed the first direct treatment of a ruptured intracranial aneurysm successfully packing the aneurysm and internal carotid artery (ICA) with muscle. Dott was also credited with introducing cervical carotid ligation for the treatment of ruptured intracranial aneurysms in 1933. The first successful description of an intracranial aneurysm clipping was in 1937, when Walter Dandy used a silver clip to treat a ruptured ICA aneurysm. Dutton and Selverstone introduced wrapping as a routine method for treating intracranial aneurysms that were difficult or impossible to clip. Suboptimal results in the 1950s led to the reappraisal of the indirect method, which was first described by Dott. Valentine Logue was responsible for its popularization advocating the proximal ligation of the dominant anterior cerebral artery in patients with ruptured anterior communicating aneurysms. Despite the technical advances, the morbidity resulting from direct treatment of intracranial aneurysms was still substantial. The introduction of the microscope to neurosurgery in the 1960s had a tremendous impact on the results of aneurysm surgery. In addition to improving the results of aneurysm surgery by experienced surgeons, the microscope accelerated the learning curve of young neurosurgeons who applied themselves to learning and

Tactics of surgical treatment of patients with unruptured asymptomatic cerebral aneurysms

To clarify the indications for surgical treatment and the principles for choosing a surgical technique for patients with unruptured asymptomatic aneurysms (UAAs) based on the results of direct and endovasal operations performed at the Burdenko Neurosurgical Institute and on the literature data. The study included 694 UAA patients (481 females (69.3%) and 213 males (30.7%)) operated on at the Burdenko Neurosurgical Institute from 1997 to 2013. The patients' age ranged from 1 to 74 years (mean age, 48.3 years). Multiple aneurysms were in 126 (18.2%) patients. Anterior circle of Willis aneurysms were in 92.8% of cases. Among these, internal carotid artery (ICA) aneurysms (46.3%) and middle cerebral artery (MCA) aneurysms (30.8%) were predominant. Microsurgical and endovascular interventions on aneurysms were performed in 665 patients (95.8%). Complete aneurysm exclusion was achieved in 94.8% of cases. A pronounced neurological deficit developed in 8 (1.2%) patients, and a moderate neurological deficit developed in 62 (9.3%) patients. Postoperative mortality was 0.5%. Surgical treatment of UAAs is associated with low disability and mortality rates. All UAAs need to be operated on, especially in young and middle age patients, if surgery is technically possible, and there are no concomitant diseases contraindicating the intervention. The choice of an UAA exclusion technique is made based on the general principles of surgical treatment of cerebral aneurysms. At present, the method of choice is endovascular surgery for most cases of vertebrobasilar basin and ICA aneurysms and a microsurgical intervention for anterior cerebral artery and MCA aneurysms.

Surgery of brain aneurysm in a BrainSuite® theater: A review of 105 cases

IntroductionThe BrainSuite® is a highly integrated operating theater designed mainly for brain tumor surgery. The issues concerning its routine use in vascular neurosurgery have not been discussed in literature to date.We report our experience of surgical treatment of cerebral aneurysms in the BrainSuite®, with a view to evaluating safety, feasibility, advantages, disadvantages, and contraindications. Material and methodsRetrospectively, we reviewed all the patients affected by ruptured and unruptured aneurysms that underwent craniotomy with clipping between January 2007 and May 2013 and a subsequent minimum 12-month follow up. Intraoperative DWI, MRA, and volumetric MRI were always performed in order to evaluate vessel patency and early ischemic lesions. The usefulness of navigation was also evaluated in terms of loss/gain of time and its effectiveness as a surgical aid to both the localization of small distal aneurysms and the preoperative planning of the clipping strategies to adopt. ResultsA total of 105 patients were included in this report. Of these, 39 and 66 were affected, respectively, by ruptured and unruptured aneurysms. The mean age was 56.1 and the male-to-female ratio was 1:2.9. The aneurysms affected, with progressively descending incidence, the MCA, ACoA, ICA bifurcation, PComA, A2, A1–A2, and C6 segment of the ICA in 40 (38.1%), 23 (22%), 15 (14.3%), 7 (6.6%), 7 (6.6%), 7 (6.6%), and 6 (5.8%) cases, respectively. The aneurysms were clipped and completely excluded from blood circulation in all cases and no difficulty was encountered in positioning and fixing the patients’ heads, despite the particular head holder of the BrainSuite®. MRI created no interference or problems in cases of carotid exposure at the neck, while harvesting of the lower-limb saphenous vein was not feasible due to the vicinity of the operating field to the magnet. Intraoperative angiography was never performed since an angiogram is not compatible with the BrainSuite. Intraoperative DWI, MRA, and volumetric MRI proved to be effective tools for post-clipping evaluation of the patency of the parent vessels and their collateral branches as well as of aneurismal occlusion. This was also checked doubly by availing also of intraoperative micro Doppler ultrasonography. Intraoperative DWI also permitted us to evaluate the presence of initial ischemic lesions as possible consequences of both direct arterial occlusion and early vasospasm related to surgical manipulation. Intraoperative navigation of brain aneurysm with 3D-model reconstructions may be of some use to younger surgeons when planning the clipping strategies and localizing the aneurysm particularly in cases, respectively, of large-complex aneurysms where the sac involves collateral branches and small aneurisms affecting both distal ACA and MCA aneurysms. The outcomes for patients, evaluated according to the GOS (Glasgow outcome score), associated significantly with the preoperative HH (Hunt and Hess) scale grading. Patients with high HH scores (IV and V) in particular showed the highest incidence of unfavorable outcome (GOS=1 or 2) ConclusionsThe BrainSuite® theater is completely suited to brain aneurysm surgery but only in cases where a combined endovascular approach may be required. It provides some advantages and few limitations compared to a normally-equipped neurosurgical operating theater; our experience shows that the technological advances of this complex operating room are useful though not essential in aneurysm surgery.

Anesthesia for the surgical treatment of cerebral aneurysms

Although most cerebral aneurysms are asymptomatic and discovered incidentally, their rupture often results in significant morbidity and mortality. The anesthesiologist may become involved in surgical clipping of aneurysms either before aneurysm rupture or after subarachnoid hemorrhage. After subarachnoid hemorrhage, a multisystemic preoperative evaluation is mandatory because both neurological complications (elevated intracranial pressure, rebleeding, hydrocephalus, vasospasm) and non-neurological complications (respiratory insufficiency, cardiac dysfunction, electrolyte abnormalities, endocrine disturbances) might influence anesthetic management. Besides being prepared for potential sudden profuse bleeding, the anesthesiologist caring for craniotomy for aneurysm clipping should follow four main principles. First, acute increase in the aneurysm transmural gradient (mean arterial pressure minus intracranial pressure) should be avoided to prevent rupture or rebleeding. Second, the cerebral perfusion pressure should be maintained with euvolemia and vasopressors to avoid brain ischemia caused either by brain retractors or temporary clipping of the feeding vessel. Third, surgical exposure should be optimized by providing brain relaxation with normal cerebral oxygenation, normal ventilation or transient hyperventilation, appropriate anesthetic choice, mannitol and perhaps lasix, and occasionally cerebrospinal fluid drainage. Fourth, early emergence is favored to allow recognition of potentially reversible complications. By being vigilant and achieving these goals, the anesthesiologist will contribute to optimal patient outcomes. The following article provides information to guide the anesthesiologist in optimal management of surgical clipping of aneurysms.

23. Are persistent changes in SEPs and MEPs sensitive for predicting postoperative limb motor deficit during cerebral aneurysm surgery?

Introduction Motor evoked potentials (MEPs) can be used as an adjunct to somatosensory evoked potentials (SEPs) to identify brain ischemia during surgical treatment of cerebral aneurysms. Persistent changes (failure to return to baseline by end of surgery) can be used to predict postoperative deficit. The sensitivity, specificity, positive and negative predictive value of persistent changes in SEPs/MEPs for predicting neurologic deficit is still being defined. In a separate study, the sensitivity of persistent changes in SEPs for predicting new limb paresis was 13%, and MEPs was 32%. In this study we evaluated those patients with new postoperative motor deficits to determine the reason for the low sensitivity. Material and methods This was a retrospective study based on 446 cerebral aneurysm patients who underwent clipping at our institution from 2009–2011. Twenty-eight patients with new postoperative motor deficits were identified. The neuromonitoring reports and medical records were reviewed in more detail in these patients. Results In the 28 patients, ten patients (36%, sensitivity) were predicted by persistent SEPs/MEPs changes. In the 18 patients whose deficits were not predicted, five patients (18%) had delayed deficits; eight (29%) had mild temporary motor deficits; in two patients (7%), monitoring was stopped less than ten minutes after aneurysms were clipped; in one patient (3.6%), no reliable SEPs were recorded on the surgery side at baseline. If the last three cases are eliminated, the sensitivity of predicting for all deficit at time when patient wake up is 50% (10/20 patients); to severe and persistent motor deficit is 83% (10/12 patients). Conclusion This study demonstrates that the reason for the low sensitivity of SEPs/MEPs is that these methods are not sensitive to delayed and/or mild temporary deficits. However, the study also shows that SEPs/MEPs have better predictability in cases of severe and persistent postoperative limb paresis.

False-negative indocyanine green videoangiography among complex unruptured middle cerebral artery aneurysms: The importance of further aneurysm inspection

Successful surgical treatment of cerebral aneurysms requires complete occlusion of the aneurysm lumen while maintaining patency of the adjacent branching and perforating arteries. Intraoperative flow assessment allows aneurysm clip repositioning in the event these requirements are not met, avoiding the risk of postoperative rehemorrhage or infarction. A number of modalities have been proposed for primarily intraoperative qualitative blood flow assessment, including microdoppler ultrasonography, intraoperative digital subtraction angiography (DSA), and more recently noninvasive fluorescent angiography including indocyanine green (ICG) fluorescent imaging. Puncture of the aneurysm dome to exclude aneurysm sac filling may also assess the efficacy of clip placement. Although a high concordance between ICG and DSA has been reported, there remains an important subset of aneurysms for which negative ICG study may erroneously suggest aneurysm occlusion. A high-risk situation for such a false-negative study is an atherosclerotic middle cerebral artery (MCA) aneurysm in which vessel wall plaque interferes with the ICG signal. Furthermore, a decreased flow within the aneurysm may not allow enough emission light for detection under the current technology. In this report, we describe our experience with cases of MCA aneurysms with false-negative ICG-VA studies requiring clip adjustment for optimal surgical treatment and discuss two illustrative cases of MCA aneurysms with intraoperative fluorescence studies that were falsely negative, requiring puncture of the aneurysm to correctly identify incomplete aneurysm occlusion.

Association between sympathetic response, neurogenic cardiomyopathy, and venous thromboembolization in patients with primary subarachnoid hemorrhage

Sympathetic activation promotes hemostasis, and subarachnoid hemorrhage (SAH) is associated with pronounced sympathetic activation. This investigation will assess whether catecholaminergic activity relates to venous thrombotic events in patients with acute SAH. Observational study of consecutive SAH grade 3-5 patients requiring ventriculostomy insertion who did not undergo open surgical treatment of cerebral aneurysm. Cerebrospinal fluid (CSF) samples were obtained within 48 h of hemorrhage for assay of catecholamines, which were related to occurrence of deep venous thrombosis (DVT) and pulmonary embolization (PE). Of the 92 subjects, mean age was 57 years, 76% were female, and 57% Caucasian; 11% experienced lower extremity (LE) DVT, 12% developed upper extremity (UE) or LE DVT, and 23% developed any DVT/PE. Mean time to occurrence of UE/LE DVT was 7.8 days (+/-5.9 days), and mean time to development of PE was 8.8 days (+/-5.4 days). In hazards analysis models, independent predictors of LE DVT included neurogenic cardiomyopathy (NC) [HR 4.97 (95%CI 1.32-18.7)], norepinephrine/3,4-dihydroxyphenylglycol ratio (NE/DHPG) [3.81 (2.04-7.14)], NE [5.91 (2.14-16.3)], and dopamine (DA) [2.27 (1.38-3.72)]. Predictors of UE/LE DVT included NC [5.78 (1.70-19.7)], cerebral infarction [4.01 (1.18-13.7)], NE [3.58 (1.40-9.19)], NE/DHPG [3.38 (1.80-6.33)] and DA [2.01 (1.20-3.35)]. Predictors of DVT/PE included Hunt-Hess grade (H/H) [3.02 (1.19-7.66)], NE [2.56 (1.23-5.37)] and 3,4-dihydroxyphenylalanine (DOPA) [3.49 (1.01-12.0)]. In severe SAH, central sympathetic activity and clinical manifestations of (nor)adrenergic activity relate to the development of venous thromboemboli. Catecholamine activation may promote hemostasis, or may represent a biomarker for venous thromboses.