Risk identification for the development of large-artery vasospasm after aneurysmatic subarachnoid hemorrhage - a multivariate, risk-, and location-adjusted prediction model.

BACKGROUND: Vasospasm of the large cerebral arteries (CVS) after aneurysmatic subarachnoid hemorrhage (aSAH) reduces cerebral perfusion and causes delayed cerebral ischemia. Although endovascular spasmolysis shows convincing angiographic results, patients often do not improve in outcome. Delayed recognition of CVS contributes substantially to this effect. Therefore, this study aimed to confirm established and to identify unknown risk factors for CVS, which can be used for risk stratification. METHODS: In this monocentric, retrospective cohort study of 853 patients with aSAH, we compared demographics, clinical, and radiographic parameters at the time of aneurysm occlusion between patients who developed CVS and those who did not. Significant cohort differences were included as predictors in a multivariate analysis to address confounding. Logistic regression models were used to determine odds ratios (ORs) for the presence of CVS for each predictor. RESULTS: Of the 853 patients treated with aSAH, 304 (32%) developed CVS. In the univariable analysis, CVS was significantly associated with young age, female sex, aneurysm location, modified Fisher score, Barrow Neurological Institute (BNI) score, and surgical interventions. In the multivariable regression analysis, we identified BNI score (OR 1.33, 95% CI 1.11 to 1.58, p=0.002), decompressive craniectomy (OR 1.93, 95% CI 1.22 to 3.04, p=0.005), and aneurysm clipping (OR 2.22, 95% CI 1.50 to 3.29, p<0.001), as independent risk factors. CONCLUSIONS: Young female patients with high BNI scores who undergo surgical interventions are more likely to develop CVS and should therefore be monitored most intensively after aneurysm occlusion.

Primary Bone Tumors of the Spine-Proposal for Treatment Based on a Single Centre Experience.

This study reports a large single-center series of primary bone tumors of the spine (PBTs). We aimed to review the concepts for management, as this kind of tumor represents a very rare entity, and also propose a new treatment algorithm. Retrospective analysis revealed 92 patients receiving surgery for PBTs from 2007 to 2019 at our center. They were analyzed based on surgical management and the course of the disease. A total of 145 surgical procedures were performed (50 cervical, 46 thoracic, 28 lumbar, and 21 sacral). Complete tumor resection was achieved in 65%, of which 22% showed tumor recurrence during follow-up (mean time to recurrence 334 days). The five-year mortality rate was significantly lower after complete resection (3% versus 25% after subtotal resection). Most of the patients improved in their symptoms through surgery. Regarding the tumor entity, the most common PBTs were vertebral hemangiomas (20%), osteoid osteomas (15%), and chordomas (16%). The Enneking graduation system showed a good correlation with the risk of recurrence and mortality. Complete resection in PBTs increased survival rates and remains the method of choice. Thus, quality of life-especially with a higher extent of resection-should be considered.

The Bigger the Better? Analysis of Surgical Complications and Outcome of the Retrosigmoid Approach in 449 Oncological Cases.

Introduction: Exposure of the posterior skull base and the cerebellopontine angle is challenging due to important neurovascular structures. The retrosigmoid approach (RSA) has become the standard method used in surgery. We report our experiences with RSAs regarding technical obstacles, complications, and approach-related outcomes. Materials and Methods: We performed a retrospective chart review at a tertiary neurosurgical center between January 2007 and September 2020. We included all patients undergoing surgery for oncologic lesions through RSAs, concentrating on surgical technique, postoperative outcome, and complications. Results: A total of 449 RSAs were included. The median age at the time of surgery was 58 years; 168 (37.4%) were male and 281 (62.6%) were female. The median approach surface was 7.8 cm2. The median tumor volume was 5.9 cm3. The median Clavien-Dindo grade was 2, the total complication rate was 28.7%, and gross total resection (GTR) was 78.8%. Findings revealed that tumor volume had no significant impact on postoperative complications in general (p = 0.086) but had a significant impact on postoperative hemorrhage (p = 0.037) and hydrocephalus (p = 0.019). Tumor volume was significant for several preoperative symptoms (p < 0.001). The extent of the approach had no significant impact on complications in general (p = 0.120) but was significant regarding postoperative cerebrospinal fluid (CSF) leaks (p = 0.008). Craniotomy size was not significant regarding GTR (p = 0.178); GTR rate just missed significant correlation with tumor volume (p = 0.056). However, in the case of vestibular schwannomas, the size of craniotomy was important for GTR (p = 0.041). Conclusion: Tumor volume has an important impact on preoperative symptoms as well as on postoperative complications. Although the extent of the craniotomy barely missed significance regarding GTR, a correlation can be assumed. Thus, the extent of craniotomy should be taken into presurgical consideration, especially in the case of postoperative CSF leaks. Regarding vestibular schwannomas, craniotomy size plays an important role in achieving satisfactory oncological outcomes. Different approaches should be selected where necessary regarding superior resection rates.

Surgical management of spinal metastases involving the cervicothoracic junction: results of a multicenter, European observational study.

OBJECTIVE: Surgical management of spinal metastases at the cervicothoracic junction (CTJ) is highly complex and relies on case-based decision-making. The aim of this multicentric study was to describe surgical procedures for metastases at the CTJ and provide guidance for clinical and surgical management. METHODS: Patients eligible for this study were those with metastases at the CTJ (C7-T2) who had been consecutively treated in 2005-2019 at 7 academic institutions across Europe. The Spine Instability Neoplastic Score, neurological function, clinical status, medical history, and surgical data for each patient were retrospectively assessed. Patients were divided into four surgical groups: 1) posterior decompression only, 2) posterior decompression and fusion, 3) anterior corpectomy and fusion, and 4) anterior corpectomy and 360° fusion. Endpoints were complications, surgical revision rate, and survival. RESULTS: Among the 238 patients eligible for inclusion this study, 37 were included in group 1 (15%), 127 in group 2 (53%), 18 in group 3 (8%), and 56 in group 4 (24%). Mechanical pain was the predominant symptom (79%, 189 patients). Surgical complications occurred in 16% (group 1), 20% (group 2), 11% (group 3), and 18% (group 4). Of these, hardware failure (HwF) occurred in 18% and led to surgical revision in 7 of 8 cases. The overall complication rate was 34%. In-hospital mortality was 5%. CONCLUSIONS: Posterior fusion and decompression was the most frequently used technique. Care should be taken to choose instrumentation techniques that offer the highest possible biomechanical load-bearing capacity to avoid HwF. Since the overall complication rate is high, the prevention of in-hospital complications seems crucial to reduce in-hospital mortality.

Minimally invasive posterior pedicle screw fixation versus open instrumentation in patients with thoracolumbar spondylodiscitis.

BACKGROUND: Due to the aging society, the incidence of pyogenic spondylodiscitis is still rising. Although surgical treatment for spondylodiscitis in general is increasingly accepted, an optimal surgical strategy for treatment of pyogenic spinal infection has not yet been established. The aim of this study was to investigate the suitability of percutaneous posterior pedicle screw fixation for surgical treatment in patients with spondylodiscitis of the thoracolumbar spine. METHODS: We conducted a retrospective review of a consecutive cohort of patients undergoing surgical treatment for spondylodiscitis of the thoracolumbar spine between January 2017 and December 2019. We assessed intraoperative and clinical data, comparing for the classic open and the percutaneous approach. In total, we analyzed 125 cases (39 female, 86 male). The mean age was 69.49 years ± 12.63 years. RESULTS: Forty-seven (37.6%) patients were operated on by a percutaneous approach for pedicle screw fixation, and 78 (62.4%) received open surgery. There was no significant difference in the mean age of patients between both groups (p= 0.57). The time of surgery for percutaneous fixation was statistically significantly shorter (p= 0.03). Furthermore, the estimated intraoperative blood loss was significantly lower in the minimally invasive group (p < 0.001). No significant difference could be observed regarding the recurrence rate of spondylodiscitis and the occurrence of surgical site infections (p= 0.2 and 0.5, respectively). CONCLUSION: Percutaneous posterior pedicle screw fixation appears to be a feasible option for the surgical treatment of a selected patient group with spondylodiscitis of the thoracic and lumbar spine.

High-frequency spinal cord stimulation in failed back surgery syndrome patients with predominant low back pain-single-center experience.

Treatment of patients with failed back surgery syndrome (FBSS) with predominant low back pain (LBP) remains challenging. High-frequency spinal cord stimulation (HF10 SCS) is believed to achieve significant pain reduction. We aimed to evaluate the real-life efficacy of HF-10 SCS in a tertiary spine center. A prospective observational study of all patients with FBSS and predominant LBP who underwent HF-10 SCS surgery was performed between 2016 and 2018. Patients > 18 years with Visual Analogue Scale (VAS) scores of ≥ 5 for LBP and pain duration > 6 months under stable medication were implanted percutaneous under general anesthesia and a trial phase of 7-14 days was accomplished. Primary end point was a successful trial defined as ≥ 50% VAS score reduction for LBP. Thirty-four of 39 (85%) subjects had a successful trial. Fifty-three percent were female and the mean age was 69 years. Median follow-up lasted for 10 months. Devices were removed after a median of 10 months in 5 cases. Remaining 29 patients stated significant VAS score reduction for LBP from 8.1 to 2.9 and VAS for leg pain from 4.9 to 2.2. Twenty-four percent of all patients were able to discontinue their opioids. Eight of 9 patients (89%) with signs of adjacent disc disease and 7 of 10 (70%) patients with hardware failure were successfully implanted with significant VAS reduction for LBP. HF-10 SCS achieves significant pain reduction in most patients with FBSS and predominant LBP. It might be an efficient alternative to revision surgery.

Fungal brain infection-no longer a death sentence.

The aim of this case series was to provide a modern cohort of patients with cerebral aspergillosis and show the effectiveness of modern treatment concepts. In a 10-year period from January 2009 to January 2019, we identified 10 patients (6 male, 4 female) who received surgery or frameless stereotactic drainage of a cerebral aspergilloma at our center. Patients' and disease characteristics were recorded. The median age was 65 (range 45 to 83). We conducted 133 cranial surgeries in 100 patients due to cerebral brain abscess (BA) during that time, which leads to a percentage of 10% of aspergilloma within BAs in our patient sample. We performed 3.1 surgeries per patient followed by antifungal treatment for 6 months (= median) according to the microbiological findings. Regarding comorbidities, the mean Charlson comorbidity index (CCI) at the time of admission was 5, representing an estimated 10-year survival of 21%. Six (60%) of 10 patients showed conditions of immunosuppression, one suffered endocarditis after replacement of aortic valves. Four patients showed associated frontobasal bone destruction, mycotic aneurysms, or thromboses. The mean duration of hospital stay was 37 days. Mortality was much lower than in literature. Sixty percent of the patients died during the follow-up period. The outcome of the two immunocompetent patients was more favorable. Cerebral aspergillosis is a rare, but still life-threatening, condition, which predominantly occurs in immunosuppressive conditions. Due to radical surgical and antifungal therapy for several months, mortality can be reduced dramatically.

Cranioplasty following decompressive craniectomy: minor surgical complexity but still high periprocedural complication rates.

Cranioplasty following decompressive craniectomy is of low surgical complexity, so much so that it has become the "beginners" cranial case. However, these "simple" procedures may have high complication rates. Identification of specific risk factors would allow targeted intervention to lower the complication rates. The aim of this study was to assess the rate of complications and to evaluate potential risk factors. We conducted a review of all patients who underwent cranioplasty in our center following decompressive craniectomy for stroke or brain trauma between 2009 and 2016. One hundred fifty-two patients were identified. Fifty-three percent were male. Mean age was 48 (range 11-78). Median time from craniectomy until cranioplasty was 102 days (range 14-378). The overall rate of complications, such as postoperative bleeding, seizures, postoperative infection, and hydrocephalus, was 30%. The mortality rate was 1%. None of the following potential risk factors was associated with significantly increased risk of periprocedural complications: gender (p = 0.34), age (p = 0.39), cause of initial surgery (p = 0.08), duration of surgery (p = 0.59), time of surgery (0.24), surgical experience (p = 0.17), and time from craniectomy until cranioplasty (p = 0.27). The 30-day complication rate following cranioplasty is high, but serious permanent deficits from these complications were rare. We found no clear predictor for these 30-day complications, which renders its prevention difficult.

Inaccuracy of standard geriatric scores in nonagenarians following hospitalization for various spinal pathologies.

Demographic trends make it incumbent on spine surgeons to recognize the special challenges involved in caring for older patients. The aim of this study was to identify variables that may predict early mortality in geriatric patients over the age of 90 following elective hospitalization for various spinal pathologies. Retrospective analyses of all patients over the age of 90 years, which were electively treated between 2006 and 2016 at out department for various spinal conditions, were performed. Patient characteristics, type of treatment, and comorbidities were analyzed with regard to the 30-day mortality rate. Twenty-six patients were identified. Mean age was 93 years (range 91-97), 19 (73%) were female. Eighteen (69%) patients were treated operatively. Mean hospital stay was 13 days (range 2-51). Seventeen (65%) patients were on anticoagulation therapy. Mean Charlson Comorbidity Index (CCI) was 5.3 (range 1-11); mean diagnosis count (DC) was 8.3 (range 2-17); mean Geriatric Index of Comorbidity (GIC) was 2.8 (range 1-4); and mean comorbidity-polypharmacy score (GPS) was 13.3 (range 5-23). The 30-day mortality rate was 16.7% in the surgically treated group compared with 12.5% in the conservatively treated group (p = 0.9), anticoagulation therapy (p = 0.91), gender (p = 0.49), length of hospital stay (p = 0.33), GIC (p = 0.54), CCI (p = 0.74), GPS (p = 0.82), and DC (p = 0.65) did not correlate with the 30-day mortality rate. Cause of death was pulmonary embolism in two cases and unknown in one case. Thirty-day mortality rate in patients over 90 years old with degenerative spinal diseases is relatively high regardless of the treatment modality. Standard geriatric prognostic scores seem less reliable for these patients.

Craniocervical trauma above the age of 90: are current prognostic scores sufficient?

Clinical data following head or spine trauma in patients over 90 years is rare. The aim of this study was to analyze this patient cohort, assessing clinical characteristics, outcomes, and survival rates and to identify variables that may predict early mortality. A retrospective analysis of all patients over the age of 90 that were treated between January 2006 and December 2016 at our department was performed. Patient characteristics, type of injury, and comorbidities were analyzed with regard to the 30-day mortality rate as the primary outcome. One hundred seventy-nine patients were identified. Mean age was 93 (range 90-102); 105 (59%) patients were female. One hundred thirty-two (74%) and 34 (19%) of patients presented with head and spinal trauma, respectively. Fourteen patients (8%) had a combined head and spine injury. One hundred (56%) patients were treated operatively. Mean Charlson comorbidity index was 4.1 (range 0-18), mean diagnosis count was 6.2 (range 0-12), mean geriatric index of comorbidity (GIC) was 3.3 (range 1-4), and mean Barthel index was 28 (range 0-100). The 30-day mortality rate was 31%. Multivariate cox regression analysis showed that head trauma had a 1.66 hazard ratio (p = 0.036) of dying within 30 days of admission, whereas a higher Glasgow coma score and surgical treatment had a hazard ratio of 0.88 (p = 0.0001) and 0.72 (p = 0.05) to reach the primary outcome. None of the standard geriatric scores reached any significant correlation with the primary outcome. Standard geriatric prognostic scores seem less reliable to predict mortality for patients above the age of 90. Higher Glasgow coma score and surgical treatment were associated with a higher survival probability.

Permutation entropy in intraoperative ECoG of brain tumour patients in awake tumour surgery- a robust parameter to separate consciousness from unconsciousness.

Awake craniotomies represent an essential opportunity in the case of lesions in eloquent areas. Thus, optimal surveillance of the patient during different stages of sedation, as well as the detection of seizure activity during brain surgery, remains difficult, as skin electrodes for electroencephalographic (EEG) analysis are not applicable in most cases. We assessed the applicability of ECoG to monitor different stages of sedation, as well as the influence of different patient characteristics, such as tumour volume, size, entity, and age or gender on permutation entropy (PeEn). We conducted retrospective analysis of the ECoG data of 16 patients, who underwent awake craniotomies because of left-sided brain tumours at our centre between 2014 and 2016. PeEn could be easily calculated and compared using frontal and parietal cortical electrodes. A comparison of PeEn scores showed significantly higher values in awake patients than in patients under anaesthesia (p ≤ 0.004) and significantly higher ones in the state of transition than under general anaesthesia (p = 0.023). PeEn scores in frontal and parietal leads did not differ significantly, making them both applicable for continuous surveillance during brain surgery. None of the following clinical characteristics showed significant correlation with PeEn scores: tumour volume, WHO grade, first or recurrent tumour, gender, and sex. Being 50 years or older led to significantly lower values in parietal leads but not in frontal leads. ECoG and a consecutive analysis of PeEn are feasible and suitable for the continuous surveillance of patients during awake craniotomies. Hence, the analysis is not influenced by patients' clinical characteristics.

The implementation of an infection prevention bundle reduces surgical site infections following cranial surgery.

BACKGROUND: The benefit of an infection prevention bundle made up of five basic procedures to avoid surgical site infections (SSIs) following cranial surgery was evaluated. METHODS: Data from all patients with first time elective brain surgery from March 2014 till May 2016 were analyzed. In April 2015, an infection prevention bundle was implemented. The rate of SSIs after first time elective cranial surgery of patients operated 1 year before and 1 year after the implementation was compared. RESULTS: Of the 321 cases operated before the implementation of the infection prevention bundle, 13 cases (4%) developed a SSI. After the implementation, only 6 patients out of 288 were re-operated due to a SSI (2%). The most frequent etiological germ cultivated was Staphylococcus aureus. CONCLUSION: The implementation of a bundle of 5 basic infection prevention steps leads to a clinical relevant reduction of SSIs.

Clinical Characteristics and Course of Postoperative Brain Abscess.

BACKGROUND: Cerebral abscesses after brain surgery are rare but severe and life-threatening complications. We sought to analyze the clinical aspects of those patients and thereby reveal risk factors and the relevant aspects for their future therapy. METHODS: We identified 44 patients (23 male, 21 female) undergoing surgery or frameless stereotactic drainage at our center from March 2009 to January 2018. We conducted 12,101 cranial surgeries during that time. RESULTS: The mean age was 55 years (range 21-82 years). The median duration between brain surgery and the after brain abscess was 1.5 months (range 1-23 months). Previous brain surgeries were emergency procedures in 27% of the cases. The frequency of surgery type was as follows: tumor resection (61%), craniotomy for traumatic brain injury (16%), aneurysm surgery (7%), biopsies (5%), hemicraniectomy after malignant cerebral infarction (5%), and other. We performed 1.3 surgeries per patient followed by antibiotic treatment for 4 weeks (=median) according to the respective germ spectrum. The germ entity was successfully identified in 39 patients (89%). In 18 cases (41%), we identified Staphylococcus aureus. In total, 20.5% of the patients died during the follow-up period. The mortality rate for patients with isolated bacteria was 18% compared with 40% for patients without isolation of specific microorganisms. CONCLUSIONS: Secondary brain abscess is a rare complication and occurs mainly in patients with tumors and patients receiving emergency surgery. In total, 41% of the patients suffered from a S. aureus infection. Isolation of the responsible microorganisms is often possible and leads to improved outcomes.

Clinical characteristics and course of primary brain abscess.

BACKGROUND: Due to improved diagnostic methods, the incidence of brain abscess is still rising. Therefore, clear and evidence-based therapy for the patients who suffer from brain abscesses is necessary. Brain abscesses are potentially life-threatening conditions that possibly lead to permanent injuries even after sufficient healing has taken place. The aims of this study were to analyze the clinical aspects of patients with brain abscesses and thereby to reveal the relevant aspects for the future treatment of the brain lesions. METHODS: We retrospectively identified 47 patients (24 male, 23 female) who had received surgery or undergone the frameless stereotactic drainage of brain abscesses in our center from March 2009 to May 2017. We analyzed the clinical characteristics of the patients, as well as comorbidities and outcomes. RESULTS: The mean age was 58 (range 7 to 86). Focus identification was successful in 28 patients (60%), with the most frequent causes of brain abscesses including the following: sinusitis (25%), dental infections (25%), and mastoiditis (21%). The mean Charlson Comorbidity Index was 1.57. Among the patients, 34% showed immunosuppressive conditions. We performed 1.5 surgeries per patient (53% via craniotomy, 28% biopsies or stereotactic drainage, 19% both procedures), followed by antibiotic treatment for 6.5 weeks (mean). In 30% of patients, no bacteria could be isolated. During the follow-up period (a median of 12 months), 23.4% of the patients died. The mortality rate during the initial hospital stay was 4.3%. CONCLUSION: One third of the patients with brain abscesses showed immunosuppressive conditions, whereas brain abscesses also often occur in patients with good medical conditions. The isolation of the focus of infection is often possible. Surgical procedures showed very good outcomes. Patients over 60 years showed significantly worse clinical outcomes.

Impact of NKT Cells and LFA-1 on Liver Regeneration under Subseptic Conditions.

BACKGROUND: Activation of the immune system in terms of subseptic conditions during liver regeneration is of paramount clinical importance. However, little is known about molecular mechanisms and their mediators that control hepatocyte proliferation. We sought to determine the functional role of immune cells, especially NKT cells, in response to partial hepatectomy (PH), and to uncover the impact of the integrin lymphocyte function-associated antigen-1 (LFA-1) on liver regeneration in a subseptic setting. METHODS: Wild-type (WT) and LFA-1-/- mice underwent a 2/3 PH and low-dose lipopolysaccharid (LPS) application. Hepatocyte proliferation, immune cell infiltration, and cytokine profile in the liver parenchyma were determined. RESULTS: Low-dose LPS application after PH results in a significant delay of liver regeneration between 48h and 72h, which is associated with a reduced number of CD3+ cells within the regenerating liver. In absence of LFA-1, an impaired regenerative capacity was observed under low-dose LPS application. Analysis of different leukocyte subpopulations showed less CD3+NK1.1+ NKT cells in the liver parenchyma of LFA-1-/- mice after PH and LPS application compared to WT controls, while CD3-NK1.1+ NK cells markedly increased. Concordantly with this observation, lower levels of NKT cell related cytokines IL-12 and IL-23 were expressed in the regenerating liver of LFA-1-/- mice, while the expression of NK cell-associated CCL5 and IL-10 was increased compared to WT mice. CONCLUSION: A subseptic situation negatively alters hepatocyte proliferation. Within this scenario, we suggest an important impact of NKT cells and postulate a critical function for LFA-1 during processes of liver regeneration.