Erdem Güresir

Recording, analysis, and interpretation of spreading depolarizations in neurointensive care: Review and recommendations of the COSBID research group

Spreading depolarizations (SD) are waves of abrupt, near-complete breakdown of neuronal transmembrane ion gradients, are the largest possible pathophysiologic disruption of viable cerebral gray matter, and are a crucial mechanism of lesion development. Spreading depolarizations are increasingly recorded during multimodal neuromonitoring in neurocritical care as a causal biomarker providing a diagnostic summary measure of metabolic failure and excitotoxic injury. Focal ischemia causes spreading depolarization within minutes. Further spreading depolarizations arise for hours to days due to energy supply-demand mismatch in viable tissue. Spreading depolarizations exacerbate neuronal injury through prolonged ionic breakdown and spreading depolarization-related hypoperfusion (spreading ischemia). Local duration of the depolarization indicates local tissue energy status and risk of injury. Regional electrocorticographic monitoring affords even remote detection of injury because spreading depolarizations propagate widely from ischemic or metabolically stressed zones; characteristic patterns, including temporal clusters of spreading depolarizations and persistent depression of spontaneous cortical activity, can be recognized and quantified. Here, we describe the experimental basis for interpreting these patterns and illustrate their translation to human disease. We further provide consensus recommendations for electrocorticographic methods to record, classify, and score spreading depolarizations and associated spreading depressions. These methods offer distinct advantages over other neuromonitoring modalities and allow for future refinement through less invasive and more automated approaches.

Poor-Grade Aneurysmal Subarachnoid Hemorrhage: Factors Influencing Functional Outcome—A Single-Center Series

OBJECTIVEnPatients presenting with poor-grade aneurysmal subarachnoid hemorrhage (SAH) have commonly been reported to have a poor prognosis; however, several reports suggest a favorable outcome in a subgroup of patients. We analyzed our database to identify factors determining functional outcome after poor-grade SAH.nnnMETHODSnDuring the period 2004-2014, 248 patients with poor-grade SAH were treated in our institution. Poor-grade SAH was defined as World Federation of Neurological Surgeons grades IV-V on admission. Data including patient characteristics, treatment modality, radiologic features, and functional neurologic outcome were assessed and further analyzed. Outcome was assessed according to the modified Rankin Scale after 6 months and stratified into favorable (modified Rankin Scale score 0-2) versus unfavorable (modified Rankin Scale score 3-6). A multivariate analysis was performed to identify predictors of functional outcome.nnnRESULTSnA favorable outcome was achieved in 24% of patients with poor-grade SAH. Patients with a favorable outcome were significantly younger (P = 0.005), harbored significantly smaller aneurysms (P = 0.004), and had a lower initial World Federation of Neurological Surgeons grade (P < 0.0001). An unfavorable outcome was significantly more frequent in patients with additional space-occupying hematoma compared with patients without additional space-occupying hematoma (P = 0.0009). On multivariate analysis, patient age, World Federation of Neurological Surgeons grade V, signs of cerebral herniation, aneurysm size, and presence of space-occupying hematoma were identified as significant predictors of unfavorable outcome in patients with poor-grade SAH.nnnCONCLUSIONSnA favorable outcome was achieved in 24% of severely ill patients with poor-grade SAH. Therefore, treatment of patients with poor-grade SAH should not be omitted. Careful individualized decision making is necessary for each patient.

Cranioplasty and Ventriculoperitoneal Shunt Placement after Decompressive Craniectomy: Staged Surgery Is Associated with Fewer Postoperative Complications.

OBJECTIVEnDecompressive craniectomy (DC) requires later cranioplasty (CP) in survivors. However, if additional ventriculoperitoneal shunt (VPS) placement due to shunt-dependent hydrocephalus is necessary, the optimal timing of both procedures still remains controversial. We therefore analyzed our computerized database concerning the optimal timing of CP and VPS regarding postoperative complications.nnnMETHODSnFrom 2009-2014, 41 cranioplasty procedures with simultaneous or staged VPS placement were performed at the authors institution. Patients were stratified into two groups according to the time from CP to VPS (simultaneous and staged). Patient characteristics, timing of CP and VPS, as well as procedure-related complications, were assessed and analyzed.nnnRESULTSnOverall CP and VPS were performed simultaneously in 41% and in staged fashion in 59% of the patients. The overall complication rate was 27%. Patients who underwent simultaneous CP and VPS suffered significantly more often from complications compared with patients who underwent staged CP and VPS procedures (47% vs. 12%; P = 0.03). Patients with simultaneous CP and VPS had a significantly higher rate of infectious postoperative complications compared with patients with staged procedures (P = 0.003). On multivariate analysis, simultaneous CP and VPS procedure was the only significant predictor of postoperative complication after CP and VPS (P = 0.03).nnnCONCLUSIONnWe provide detailed data on surgical timing and complications for cranioplasty and ventriculoperitoneal shunt placement after DC. The present data suggest that patients who undergo staged CP and VPS procedures might benefit from a lower complication rate. This might influence future surgical decision making regarding optimal timing of CP and VPS placement.

Posterior Reversible Encephalopathy Syndrome as an Overlooked Complication of Induced Hypertension for Cerebral Vasospasm Systematic Review and Illustrative Case

Background and Purpose— Delayed cerebral ischemia associated with cerebral vasospasm is a common cause of secondary neurological decline after aneurysmal subarachnoid hemorrhage (SAH). Triple-H therapy, induced hypertension, hypervolemia, and hemodilution, is often used to treat cerebral vasospasm. However, hypertensive treatment may carry significant medical morbidity, including cardiopulmonary, renal, and intracranial complications. Posterior reversible encephalopathy syndrome (PRES) is a reversible intracranial complication that has rarely been reported in the setting of induced hypertension. Methods— We present an illustrative case of PRES in a patient with induced hypertension for SAH-related cerebral vasospasm and performed a systematic review. Furthermore, the electronic database MEDLINE was searched for additional data in published studies of PRES after induced hypertension. Results— Overall, 7 case reports presenting 10 patients who developed PRES secondary to induced hypertension were found. Eighty-two percent of the patients were women. In all cases, the clinical symptoms were attributed to cerebral vasospasm before the diagnosis of PRES. The time from onset of induced hypertension to the development of PRES was 7.8±3.8 days. After the diagnosis of PRES and careful taper down of the blood pressure, the neurological symptoms resolved almost completely within a few days in all patients. Conclusions— PRES in the setting of SAH is an overlooked complication of hypertensive therapy for the treatment of vasospasm. However, the diagnosis of this phenomenon is crucial given the necessity to reverse hypertensive therapy, which is contrary to the usual management of patients with vasospasm.

Surgical Treatment of Spinal Dural Arteriovenous Fistula: Management and Long-Term Outcome in a Single-Center Series.

OBJECTIVEnTo perform a retrospective chart review of surgically treated patients with spinal dural arteriovenous fistula (SDAVF), a rare disease but the most common vascular malformation of the spine, focusing on clinical characteristics and functional outcome during long-term follow-up.nnnMETHODSnBetween June 1990 and April 2012, 29 patients with SDAVFs were treated surgically in a single institution. Patient characteristics, time from onset of symptoms to treatment, radiologic features, treatment-related complications, and functional outcome were analyzed. Outcome was assessed according to the Aminoff-Logue scale during follow-up. Results of magnetic resonance imaging scans performed during long-term follow-up were correlated with functional outcome.nnnRESULTSnThere were 3 female (10%) and 26 male (90%) patients with SDAVFs treated surgically. Mean age was 61 years ± 11. Location of the fistula was at the thoracic level in 20 patients (69%), at the lumbar level in 8 patients (28%), and at the sacral level in 1 patient (3%). Mean postoperative Aminoff-Logue scale scores regarding gait and micturition improved after treatment compared with preoperatively (P = 0.02; P = 0.03). After surgical treatment, 22 patients (76%) achieved improvement in neurologic symptoms. In 6 patients (21%), neurologic status was the same as preoperatively. In 1 patient (3%), neurologic status worsened. Medullary signal alteration of diagnostic magnetic resonance imaging scans did not correlate with functional outcome (P = 0.2). Mean follow-up time was 63 months ± 55. All SDAVFs were treated in a single session without recurrence during the long-term follow-up period.nnnCONCLUSIONSnSurgical treatment of SDAVFs is safe and effective and leads to an improvement of neurologic symptoms in most patients. Surgical treatment of SDAVFs also provides long-term stability.

Acute Traumatic Subdural Hematoma: Surgical Management in the Presence of Cerebral Herniation–A Single-Center Series and Multivariate Analysis

BACKGROUNDnTraumatic acute subdural hematoma (aSDH) is a severe disease. Surgical treatment is still controversially discussed, especially in patients with additional signs of cerebral herniation. However, previously investigated patient populations were heterogeneous. We therefore performed an analysis of our institutional data in a large homogenous selection of patients with traumatic aSDH to analyze factors determining clinical outcome.nnnMETHODSnBetween 2010 and 2014, 196 patients with aSDH underwent surgical treatment in our department. Information including patient characteristics, treatment modality, radiologic features, and functional outcome were analyzed. Outcome was assessed according to the Glasgow Outcome Scale (GOS) at 6 months and was dichotomized into favorable (GOS score, 1-3) and unfavorable (GOS score 4-5) outcome. Furthermore, a multivariate analysis was performed to identify independent predictors of functional outcome.nnnRESULTSnOverall, 26% of patients with aSDH achieved favorable outcome. In further analysis, unilateral or bilateral dilated pupils as a sign of cerebral herniation were present in 47% of the included patients. In the multivariate analysis, age >70 years and the presence of cerebral herniation were significant prognostic predictors for unfavorable outcome in patients with aSDH. However, 15% of patients with aSDH and signs of cerebral herniation achieved favorable outcome during follow-up.nnnCONCLUSIONSnWe provide detailed data on patients with aSDH and signs of cerebral herniation. Despite mydriasis, favorable outcome may be achieved in many patients. Nevertheless, careful individual decision making is necessary for each patient, especially when signs of cerebral herniation have persisted for a long time.

Decompressive Craniectomy for Stroke: Early Cranioplasty Is a Predictor for Postoperative Complications.

BACKGROUNDnPrevious clinical studies assumed that early cranioplasty (CP) was mandatory for a favorable neurologic recovery after decompressive craniectomy (DC) for malignant stroke. However, the appropriate timing of the CP procedure after DC remains controversial. This study assessed patients who underwent DC because of cerebral ischemia to determine the appropriate time point of CP and surgical-associated complications.nnnMETHODSnData from the period 2007-2014 were retrospectively evaluated. CP was performed in 75 patients who previously underwent DC because of supratentorial cerebral infarction. Patients were divided into 2 groups (early CP vs. late CP) according to the time from DC to CP (<3 months vs. ≥3 months). Patient characteristics, timing of CP, and postoperative complications associated with CP were analyzed.nnnRESULTSnCP was performed early in 12 patients (16%) and late in 63 patients (84%). The complication rate after CP was 18%; complications included wound healing disturbance in 8 patients (11%), epidural hematoma or subdural hematoma in 4 patients (4%), and others in 2 patients (3%). Patients with early CP experienced significantly more complications compared with patients with late CP after initial DC (5 of 12 patients [42%] vs. 8 of 63 patients [13%]; Pxa0= 0.02). In multivariate analysis, early CP was a significant predictor of postoperative complications after CP (odds ratioxa0= 6.04; 95% confidence interval, 1.4-24.9; Pxa0= 0.01).nnnCONCLUSIONSnThe present data suggest that patients who underwent DC for stroke might benefit from CP performed >3 months after DC owing to a lower rate of wound infection.

Accuracy and Safety of Ventriculostomy Using Two Different Procedures of External Ventricular Drainage: A Single-Center Series

Background and Study Aims Patients with acute hydrocephalus are treated by either insertion of a conventional external ventricular drain (EVD) or percutaneous needle trephination (PNT) at our institution, depending on the acuteness of intervention and the severity of illness. We compared both procedures regarding accuracy and safety necessitating surgical revision of EVD or PNT. Methods Between January 2012 and January 2014, 451 ventriculostomies were performed in 301 patients at our institution. All patients underwent routine computed tomography after insertion of the ventricular drain during the treatment course. Patient characteristics, underlying pathology, ventriculostomy modality, radiologic features, catheter tip location, and treatment‐related complications were analyzed. Results A total of 307 of 451 ventriculostomy procedures (68%) were performed as conventional EVD, and 144 (32%) were performed as PNT. Overall, 11% of patients with conventional EVD underwent surgical revision due to lacking accuracy, infection, or hemorrhage; 7% of patients with PNT underwent surgical revision (p = 0.2). However, multivariate analysis revealed that only “hospital stay > 21 days” as an independent variable was significantly associated with surgical revision after ventriculostomy. Conclusion The present data indicate that PNT has a similar safety profile in emergency situations in critically ill patients who need immediate treatment for acute hydrocephalus when compared with the conventional EVD procedure.

Anticoagulation Therapy in Patients Suffering from Aneurysmal Subarachnoid Hemorrhage: Influence on Functional Outcome—a Single-Center Series and Multivariate Analysis

INTRODUCTIONnFavorable outcome in patients presenting with aneurysmal subarachnoid hemorrhage (SAH) is determined by several factors. Nevertheless, data on the influence of prior use of oral anticoagulation drugs on functional outcome in patients suffering from SAH are scarce. We therefore analyzed our institutional data.nnnMETHODSnFrom January 2009 to October 2015, 480 patients suffering from aneurysmal SAH were admitted to our institution. Information including patient characteristics, treatment modality, aneurysm size and location, radiologic features, and functional neurologic outcome was assessed and further analyzed. Outcome was assessed according to the modified Rankin Scale (mRS) at 6 months and stratified into favorable (mRS 0-2) versus unfavorable (mRS 3-6).nnnRESULTSnOverall, 17 of 480 patients suffering from aneurysmal SAH were on anticoagulation therapy before ictus (4%). Patients without anticoagulation therapy were significantly younger compared with patients with anticoagulation therapy before SAH (Pxa0= 0.005). Furthermore, patients without anticoagulation therapy presented in a significantly better clinical condition compared with patients with anticoagulation therapy before SAH (Pxa0=xa00.02). Additionally, patients without anticoagulation therapy achieved significantly more often favorable functional outcome compared with patients with anticoagulation therapy before SAH (Pxa0= 0.02). However, anticoagulation therapy was not identified as a significant and independent predictor for unfavorable outcome in the multivariate logistic regression analysis.nnnCONCLUSIONnAnticoagulation therapy has not been identified as a significant and independent factor influencing functional outcome in patients suffering from SAH. Therefore treatment should not be omitted. Nevertheless, cautious management is necessary in patients with known anticoagulation therapy before SAH.

Transsphenoidal pituitary surgery: comparison of two sellar reconstruction techniques and their effect on postoperative cerebrospinal fluid leakage

Transsphenoidal surgery is a common procedure in patients with pituitary adenomas. Several techniques have been previously postulated to achieve sufficient sellar reconstruction to avoid cerebrospinal fluid (CSF) leakage. We analyzed our institutional database concerning two sellar reconstruction techniques and development of postoperative CSF leakage. From 2009 to 2015, 255 patients underwent transsphenoidal pituitary surgery at our institution. According to the technique used for sellar reconstruction, patients were divided into two groups: (1) with muscle patch and fibrin glue and (2) with fibrin glue alone. Postoperative CSF leakage occurred in 7% of the patients. Occurrence of postoperative CSF leakage did not differ significantly between both sellar reconstruction techniques (pu2009=u20090.2). Patients who underwent sellar reconstruction with fibrin glue alone had significantly shorter operating time (pu2009<u20090.0001), as well as shorter length of hospital stay (pu2009=u20090.01). On multivariate analysis, occurrence of intraoperative CSF leakage was the only predictor for postoperative CSF leakage (pu2009<u20090.0001). The present data suggests that sellar reconstruction after transsphenoidal pituitary surgery seems to be equally effective in preventing postoperative CSF leakage. However, the use of fibrin glue alone results in shorter hospital stay and operating time without exposing patients to more frequent CSF leakage.