Clinical experiences and learning curves from robot-assisted neurosurgical biopsies with Stealth Autoguide™.

Background: Biopsies of intracranial lesions are a cornerstone in the diagnosis of unresectable tumors to guide neurooncological treatment; however, the procedure is also associated with risks. The results from the cranial robot guidance system Stealth Autoguide™ were studied after introduction at a neurosurgical department. Primary aims include the presentation of clinical and radiological data, accuracy of radiological diagnosis, learning curves of the new technology, diagnostic yield, and precision. The secondary aim was to study complications. Methods: Retrospective data inclusion was performed on patients ≥ 18 years undergoing biopsy with Stealth Autoguide™ due to suspected brain tumors in the first 3 years after the introduction of the technique. Data regarding clinical characteristics, intraoperative variables, pathological diagnosis, and complications were recorded. Analyses of learning curves were performed. Results: A total of 79 procedures were performed on 78 patients with a mean age of 62 years (SD 12.7, range 23-82), 30.8% were female. Tumors were often multifocal (63.3%) and supratentorial (89.9%). The diagnostic yield was 87.3%. The first-hand radiological diagnosis was correct in 62.0%. A slight decrease in operation time was observed, although not significant. The surgeon contributed to 12% of the variability. Conclusions: Robot-assisted biopsies with Stealth Autoguide™ seem to be comparable, with regards to complications, to frame-based and other frameless neurosurgical biopsies. Learning curves demonstrated no statistical differences in time of surgery and only 12% surgeon-related variation (ie, variation caused by the change of performing surgeon), suggesting a successful implementation of this technical adjunct.

[Treatment of traumatic brain injury in the acute setting - An overview]. / Modern handläggning minimerar följder av traumatisk hjärnskada.

Traumatic brain injury (TBI) is the leading cause of death among the young, and has an increasing incidence among the elderly. In Sweden there are 20 000 new TBI cases each year, of which most are mild. The primary impact can lead to different types of brain hemorrhages, fractures and diffuse axonal injuries. The level of consciousness is used to define injury severity. Of all TBIs,  4-5 percent require surgical intervention. The primary impact initiates injury processes exacerbating the initial brain injury, and the goal of the acute management and neurointensive care treatment is to prevent these secondary insults. Among unconscious TBI patients, monitoring of intracranial pressure and cerebral perfusion pressure (CPP, defined as the difference between the mean arterial pressure and intracranial pressure) is routine. In this article we present an overview on different types of TBI, and describe the treatment of patients in the acute setting.

Risk and cause of death in post-traumatic epilepsy: a register-based retrospective cohort study.

OBJECTIVE: Post-traumatic epilepsy (PTE) is common, but its impact on survival after traumatic brain injury (TBI) of different severity and in different demographic patient groups is unknown. We analyzed the risk of death associated with PTE with adjustment for TBI severity, causes of death, and the contribution of epilepsy as direct or contributing cause of death. METHODS: Register-based, retrospective cohort study. All individuals hospitalized in Sweden for a TBI between 2000 and 2010 without prior seizures were identified in the National Patient Register, with follow-up until 2017. Subsequent epilepsy was identified by ICD-10 codes. Time-dependent Cox proportional hazard ratio (HR) was used to assess hazard of death, with epilepsy as a time-updated covariate. Adjusted analyses for age, gender, injury severity and comorbidities were also performed. Causes of death were analyzed using the Cause of Death Register. RESULTS: Among 111 947 individuals with TBI, subsequent epilepsy diagnosis was associated with a crude HR of 2.3 (95% CI: 2.2-2.4) for death. Stratified analyses showed a HR of 7.8 (95% CI: 6.5-9.4) for death in younger individuals. Epilepsy was a more common underlying cause of death in younger individuals. CONCLUSION: PTE is associated with a higher risk of death and epilepsy seems to contribute to a significant proportion of deaths, especially in younger age groups. Future studies on whether improved epilepsy treatment can reduce mortality are needed.

Long-term outcomes after aneurysmal subarachnoid hemorrhage: A prospective observational cohort study.

OBJECTIVES: The survival rates for patients affected by aneurysmal subarachnoid hemorrhage (aSAH) have increased in recent years; however, many patients continue to develop cognitive dysfunctions that affect their quality of life. The commonly used outcome measures often fail to identify these cognitive dysfunctions. This study aimed to evaluate the long-term outcomes at 1 and 3 years after aSAH to assess changes over time and relate outcomes to patient characteristics and events during the acute phase. MATERIALS AND METHODS: This prospective observational study included patients that experienced aSAH. Patients were assessed according to the extended Glasgow Outcome Scale, Life Satisfaction Questionnaire, Mayo-Portland Adaptability inventory-4, and Mental Fatigue scale. RESULTS: Patients were assessed after 1 year (n = 62) and 3 years (n = 54). At 3 years, the extended Glasgow Outcome Scale score improved in 15% and worsened in 12% of the patients. Mental fatigue was observed in 57% of the patients at 1 year. Patients <60 years of age at the time of aSAH had more self-assessed problems, including pain/headache (p < .01), than patients >60 years of age. Patients with delayed cerebral ischemia during the acute phase reported more dissatisfaction at 3 years, whereas no significant result was seen at 1 year. CONCLUSIONS: Cognitive dysfunction, especially mental fatigue, is common in patients with aSAH, which affects quality of life and recovery. Patient outcome is a dynamic process developing throughout years after aSAH, involving both improvement and deterioration. This study indicates the importance of longer follow-up periods with broad outcome assessments.

Differences in Presentation, Radiological Features, and Outcomes in Traumatic Versus Spontaneous Acute Subdural Hematomas-A Single-Institution Population-Based Study.

BACKGROUND: Spontaneous acute subdural hematoma (sASDH) is a rare neurosurgical condition, with the literature mainly consisting of case reports. In the present study, we compared sASDH with traumatic ASDH (tASDH) to determine the differences in presentation, radiological features, and outcomes in a population-based setting. METHODS: All adult patients (age ≥18 years) who had undergone surgery for ASDH (n = 266), either spontaneous or traumatic, from 2010 to 2020 were included retrospectively. The cohort was divided into 2 groups for comparative analysis: sASDH group (n = 24) versus tASDH group (n = 242). RESULTS: Of the 266 patients, 24 (9.0%) had presented with sASDH. The sASDH group had a mean age of 66.2 years, and sudden headache was the most common presenting symptom (83.3%). The sASDH group had a higher Glasgow coma scale score at presentation compared with the tASDH group (Glasgow coma scale scores, 10 and 8, respectively; P < 0.01). The outcomes, assessed using the Glasgow outcome scale (GOS), revealed a greater incidence of more favorable outcomes (GOS score 4-5) for the sASDH group (72.7%) than for the tASDH group (41.5%). CONCLUSIONS: In the present population-based study of surgically evacuated ASDH cases, 9% were spontaneous without previous trauma. The outcomes (GOS scores) were significantly more favorable for those with sASDH than for those with tASDH. In one half of the patients with sASDH, arterial bleeding was noted perioperatively, although the preoperative radiological examinations revealed no abnormalities for most patients. However, the lack of sufficient examinations such as computed tomography angiography made it difficult to establish the most common etiology of bleeding in those with sASDH. Further research is warranted to determine the reference standard method for the investigation of sASDH.

A single-centre study of frame-based stereotactic brain biopsies.

OBJECTIVE: We aimed to evaluate the concordance between the image-based and the tissue-based diagnosis using frame-based stereotactic biopsy. MATERIALS AND METHODS: Medical records of biopsy procedures from 2000 to 2017 were reviewed. The radiologists' preoperative reports, biopsy procedures and postoperative histopathological diagnoses were retrieved. We compared the preoperative image-based diagnosis with the final histopathological diagnosis. RESULTS: We identified 125 biopsy procedures performed in 123 patients. The concordance between image-based and histopathological diagnoses varied between 53.3% and 87.5%. The concordance of diagnosis concerning both tumor entity (i.e. cell type) and WHO grade was 54.6%. The diagnostic yield was 95.2%. There was overall morbidity of 10.4%, and a mortality rate of 0.8%. Minor complications occurred in 4.0% of the cases, while clinically significant complications occurred in 6.4% of the cases. CONCLUSIONS: There was suboptimal concordance between radiological and histopathological diagnosis. Also, there was a tendency of histopathological undergrading. We confirm that frame-based stereotactic biopsies have a high diagnostic yield and a low rate of clinically significant complications and mortality.

[Paroxysmal sympathetic hyperactivity]. / ABC om Paroxysmal sympatisk hyperaktivitet.

Paroxysmal sympathetic hyperactivity (PSH) is a condition mainly described in patients after traumatic brain injury and it is also known under the terms "autonomic storm" and "dysautonomia". It affects between 8-10% of patients after traumatic brain injury and can also affect patients after other neurological diseases, such as anoxic brain injury, stroke, tumors or infections. PSH manifests with six main symptoms: tachycardia, tachypnea, hypertension, hyperthermia, hyperhidrosis and increased muscle tonus. It is of outmost importance to exclude other causes for the symptoms and there are diagnostic criteria established to identify and diagnose PSH. The treatment is pharmacological and non-pharmacological and often multimodal. PSH is probably underdiagnosed and increased awareness is needed.

Selection of CT variables and prognostic models for outcome prediction in patients with traumatic brain injury.

BACKGROUND: Traumatic brain injuries (TBI) are associated with high risk of morbidity and mortality. Early outcome prediction in patients with TBI require reliable data input and stable prognostic models. The aim of this investigation was to analyze different CT classification systems and prognostic calculators in a representative population of TBI-patients, with known outcomes, in a neurointensive care unit (NICU), to identify the most suitable CT scoring system for continued research. MATERIALS AND METHODS: We retrospectively included 158 consecutive patients with TBI admitted to the NICU at a level 1 trauma center in Sweden from 2012 to 2016. Baseline data on admission was recorded, CT scans were reviewed, and patient outcome one year after trauma was assessed according to Glasgow Outcome Scale (GOS). The Marshall classification, Rotterdam scoring system, Helsinki CT score and Stockholm CT score were tested, in addition to the IMPACT and CRASH prognostic calculators. The results were then compared with the actual outcomes. RESULTS: Glasgow Coma Scale score on admission was 3-8 in 38%, 9-13 in 27.2%, and 14-15 in 34.8% of the patients. GOS after one year showed good recovery in 15.8%, moderate disability in 27.2%, severe disability in 24.7%, vegetative state in 1.3% and death in 29.7%. When adding the variables from the IMPACT base model to the CT scoring systems, the Stockholm CT score yielded the strongest relationship to actual outcome. The results from the prognostic calculators IMPACT and CRASH were divided into two subgroups of mortality (percentages); ≤50% (favorable outcome) and > 50% (unfavorable outcome). This yielded favorable IMPACT and CRASH scores in 54.4 and 38.0% respectively. CONCLUSION: The Stockholm CT score and the Helsinki score yielded the closest relationship between the models and the actual outcomes in this consecutive patient series, representative of a NICU TBI-population. Furthermore, the Stockholm CT score yielded the strongest overall relationship when adding variables from the IMPACT base model and would be our method of choice for continued research when using any of the current available CT score models.

Post-traumatic epilepsy in adults: a nationwide register-based study.

OBJECTIVE: Traumatic brain injury (TBI) is a leading cause of epilepsy. Our aim was to characterise the risk of epilepsy in adults after hospitalisation for TBI. METHODS: Register-based cohort study. All individuals aged 18-100 with a first hospitalisation for TBI in the comprehensive national patient register in Sweden between 2000 and 2010 (n=111 947) and three controls per exposed (n=325 881), matched on age and sex were included. Exposed individuals were categorised according to TBI severity. Kaplan-Meier curves were used to estimate the risk of epilepsy and Cox regression to estimate the hazard in univariate or multivariate regression. RESULTS: The 10-year risk of epilepsy was 12.9% (95% CI 11.7% to 14.1%) for focal cerebral injuries, 8.1% (95% CI 7.5% to 8.7%) for diffuse cerebral injuries, 7.3% (95% CI 6.9% to 7.7%) for extracerebral injuries, 2.8% (95% CI 2.4% to 3.2%) for skull fractures and 2.6% (95% CI 2.4% to 2.8%) for mild TBI. The risk of epilepsy after any TBI was 4.0% (95% CI 3.8% to 4.2%). The corresponding 10-year risk for controls was 0.9% (95% CI 0.9% to 0.9%). The HR increased with a more severe injury, from 3.0 (95% CI 2.8 to 3.2) for mild injury to 16.0 (95% CI 14.5 to 17.5) for focal cerebral injury. Multivariable analyses identified central nervous system (CNS) comorbidities as risk factors, but TBI remained significant also after adjustment for these. Other identified risk factors were male sex, age, mechanical ventilation and seizure during index hospitalisation. CONCLUSION: The risk of post-traumatic epilepsy is considerable, also with adjustments for CNS comorbidities.

Heart rate variability monitoring for the detection of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage.

BACKGROUND: Delayed cerebral ischemia (DCI) is a major cause of impaired outcome after aneurysmal subarachnoidal hemorrhage (aSAH). In this observational cohort study we investigated whether changes in heart rate variability (HRV) that precede DCI could be detected. METHODS: Sixty-four patients with aSAH were included. HRV data were collected for up to 10 days and analyzed offline. Correlation with clinical status and/or radiologic findings was investigated. A linear mixed model was used for the evaluation of HRV parameters over time in patients with and without DCI. Extended Glasgow outcome scale score was assessed after 1 year. RESULTS: In 55 patients HRV data could be analyzed. Fifteen patients developed DCI. No changes in HRV parameters were observed 24 hours before onset of DCI. Mean of the HRV parameters in the first 48 hours did not correlate with the development of DCI. Low/high frequency (LF/HF) ratio increased more in patients developing DCI (ß -0.07 (95% confidence interval, 0.12-0.01); P = .012). Lower STDRR (standard deviation of RR intervals), RMSSD (root mean square of the successive differences between adjacent RR intervals), and total power (P = .003, P = .007 and P = .004 respectively) in the first 48 hours were seen in patients who died within 1 year. CONCLUSION: Impaired HRV correlated with 1-year mortality and LF/HF ratio increased more in patients developing DCI. Even though DCI could not be detected by the intermittent analysis of HRV used in this study, continuous HRV monitoring may have potential in the detection of DCI after aSAH using different methods of analysis.

Mental fatigue assessment may add information after aneurysmal subarachnoid hemorrhage.

BACKGROUND: Mental fatigue, as part of cognitive dysfunction, has been reported to be common after subarachnoid hemorrhage and it significantly affects quality of life. AIMS OF THE STUDY: The aim of this study was to assess mental fatigue one year after an aneurysmal subarachnoid hemorrhage and to correlate the degree of mental fatigue to functional outcome assessed with the Extended Glasgow Outcome Scale (GOSE). METHODS: One year after an aneurysmal subarachnoid hemorrhage, the GOSE was assessed and a questionnaire for self-assessment of mental fatigue, the Mental Fatigue Scale, was distributed to all included patients. The maximum score is 42 and a score of ≥10.5 indicates mental fatigue. RESULTS: All patients with GOSE 8, indicating full recovery, had a mental fatigue score of <10.5. A linear correlation between the GOSE and the mental fatigue score was observed (p < 0.0001). CONCLUSIONS: Patients with a favorable outcome and GOSE 5-7 could benefit from the assessments of mental fatigue in order to receive satisfactory rehabilitation.

Clinical Evaluation of a Microwave-Based Device for Detection of Traumatic Intracranial Hemorrhage.

Traumatic brain injury (TBI) is the leading cause of death and disability among young persons. A key to improve outcome for patients with TBI is to reduce the time from injury to definitive care by achieving high triage accuracy. Microwave technology (MWT) allows for a portable device to be used in the pre-hospital setting for detection of intracranial hematomas at the scene of injury, thereby enhancing early triage and allowing for more adequate early care. MWT has previously been evaluated for medical applications including the ability to differentiate between hemorrhagic and ischemic stroke. The purpose of this study was to test whether MWT in conjunction with a diagnostic mathematical algorithm could be used as a medical screening tool to differentiate patients with traumatic intracranial hematomas, chronic subdural hematomas (cSDH), from a healthy control (HC) group. Twenty patients with cSDH and 20 HC were measured with a MWT device. The accuracy of the diagnostic algorithm was assessed using a leave-one-out analysis. At 100% sensitivity, the specificity was 75%-i.e., all hematomas were detected at the cost of 25% false positives (patients who would be overtriaged). Considering the need for methods to identify patients with intracranial hematomas in the pre-hospital setting, MWT shows promise as a tool to improve triage accuracy. Further studies are under way to evaluate MWT in patients with other intracranial hemorrhages.

Longitudinal changes in diffusion tensor imaging parameters of the corpus callosum between 6 and 12 months after diffuse axonal injury.

BACKGROUND: Magnetic resonance diffusion tensor imaging (MR-DTI) is used increasingly to detect diffuse axonal injury (DAI) after traumatic brain injury (TBI). PRIMARY OBJECTIVE: To investigate changes in the diffusion tensor imaging parameters of the corpus callosum 6 and 12 months after TBI, to optimize the timing of follow-up DTI investigations. A secondary goal was to study the relationship between DTI parameters and outcome. RESEARCH DESIGN: Longitudinal prospective study. METHODS AND PROCEDURES: MR-DTI was performed in 15 patients with suspected DAI, 6 and 12 months post-injury. Sixteen controls were also examined. Fractional anisotropy (FA) and diffusivity (trace) in the corpus callosum were analysed. The outcome measures were the extended Glasgow Outcome Scale and the Barrow Neurological Institute Screen for Higher Cerebral Functions, assessed at 6 and 12 months. MAIN OUTCOMES AND RESULTS: FA decreased and trace increased at 6 and 12 months compared to controls. Trace continued to increase even further between 6 and 12 months, while FA remained unchanged. Patients with the worst outcomes had lower FA and higher trace compared to patients with better outcomes. CONCLUSIONS: DTI parameters have not reached a stable level at 6 months after DAI, but continue to change, probably reflecting an incessant microstructural alteration of the white matter.

Serum Neurofilament Light Protein as a Marker for Diffuse Axonal Injury: Results from a Case Series Study.

Diffuse axonal injury (DAI) is an important cause of morbidity in patients with traumatic brain injury (TBI). There is currently no simple and reliable technique for early identification of patients with DAI, or to prognosticate long-term outcome in this patient group. In the present study, we examined acute serum concentrations of neurofilament light (NFL) in nine patients with severe TBI and DAI using a novel ultrasensitive single molecule array (Simoa) assay. The relationships between the NFL concentrations and MRI in the acute stage as well as clinical outcome and magnetic resonance diffusion tensor imaging (MR-DTI) parameters at 12 months were analyzed. We found that the mean NFL concentrations among the patients displayed a 30-fold increase compared with controls, and that NFL completely discriminated between the patients and controls. We also found a relationship between serum NFL and MR-DTI parameters, with higher NFL concentrations in patients with higher trace (R2 = 0.79) and lower fractional anisotropy (FA) (R 2 = 0.83). These results suggest that serum NFL may be a valuable blood biomarker for TBI, reflecting the severity of DAI.

Decline in cognitive function due to diffuse axonal injury does not necessarily imply a corresponding decline in ability to perform activities.

PURPOSE: The study explored the direction of change (decline vs. improvement) after diffuse axonal injury (DAI) in the domains of the ICF: body structure, body function, and activity. METHODS: Thirteen patients with DAI were assessed by using diffusion tensor imaging (DTI) to measure body structure, the Barrow Neurological Institute Screen for Higher Cerebral Functions (BNIS) to measure body function, and the Assessment of Motor and Process Skills (AMPS) to measure activity. The DTI, BNIS, and AMPS were applied at the acute phase (A1), and at 6 and 12 months post-injury (A2 and A3). Visual and statistical analyses were conducted to explore time-dependent changes in the ICF domains. RESULTS: Improvements were observed for most patients in all ICF domains from injury until six months. Thereafter, the results diverged, with half of the subjects showing a decline in DTI and BNIS scores between A2-A3, and all but one of the patients exhibiting identical or better A2-A3 AMPS process skill scores. CONCLUSIONS: From 6 to 12 months post-injury, some patients underwent an ongoing degenerative process, causing a decline in cognitive function. The same decline was not observed in the activity measure, which might be explained by the use of compensatory strategies. IMPLICATIONS FOR REHABILITATION: In rehabilitation it is essential to be aware that in some cases with TBI, an ongoing degenerative process in the white matter can be expected, causing an adverse late effect on cognitive function. The cognitive decline, caused by DAI, does not necessarily mean a concurrent decrease in activity performance, possibly explained by the use of compensatory strategies. This suggests that, after the post-acute phase, rehabilitation offering strategy training may be beneficial to enhance every-day functioning. Strategy use requires awareness, which imply the need to assess level of awareness in order to guide rehabilitation.

Longitudinal study of the diffusion tensor imaging properties of the corpus callosum in acute and chronic diffuse axonal injury.

BACKGROUND: Magnetic resonance diffusion tensor imaging (MR-DTI) is used increasingly to detect diffuse axonal injury (DAI) after traumatic brain injury (TBI). PRIMARY OBJECTIVE: The primary objective was to investigate the changes in the diffusion properties of the corpus callosum in the acute phase and 6 months after TBI and to examine the correlation between DTI parameters and clinical outcome. RESEARCH DESIGN: Longitudinal prospective study. METHODS AND PROCEDURES: MR-DTI was performed in eight patients with suspected DAI within 11 days and at 6 months post-injury. Six controls were also examined. Fractional anisotropy (FA), trace and parallel and perpendicular diffusivity of the corpus callosum were analysed. The main outcome was the extended Glasgow Outcome Scale score, assessed at 6 months. MAIN OUTCOMES AND RESULTS: A significant reduction in FA in the corpus callosum was seen in the acute phase in patients compared with the healthy controls. There was no significant change in the parallel or perpendicular eigenvalues or trace. At 6 months, a significant reduction in FA and a significant increase in trace and perpendicular eigenvalues were noticed compared with controls. CONCLUSIONS: The diffusion properties of the corpus callosum correlated with clinical outcome in this longitudinal investigation.