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ntroduction: Maximal safe resection is established goal of WHO grade 2 low-grade gliomas (LGG). Asleep motor mapping offers an alternative to awake surgery for tumors near motor areas and has been shown to be safe and effective in expert centers.

Research question: We aimed to identify predictors of postoperative motor deficits, and describe patient selection and intraoperative mapping techniques across Scandinavian centers.

Material and methods: We retrospectively analyzed patients (≥18) with WHO grade 2 gliomas who underwent asleep motor mapping across multiple Scandinavian neurosurgical centers. Clinical, surgical, and imaging data were extracted from medical records. The primary outcome was registered permanent postoperative motor deficits at 3 months. Associations with pre-, intraoperative, and radiological variables - including diffusion-weighted imaging (DWI) changes - were assessed using univariate and multivariate logistic regression.

Results: We included 74 patients from eight institutions. Median age was 48 years, 38 (51.4 %) were female and median preoperative tumor volume was 43.2 ml. 13 (17.6 %) patients achieved gross-total resection and median postoperative volume was 7.8 ml. Permanent postoperative motor deficits occurred in 19 cases (25.7 %), and 5 (6.8 %) were considered major deficits. In univariate analysis, preoperative motor deficits (p = 0.009), postoperative DWI changes (p = 0.022), and age (p = 0.043) were significantly associated with new or worsened permanent deficits. Only DWI changes and age was confirmed in penalized multivariate logistic regression.

Discussion and conclusion: Postoperative motor deficits were common despite use of asleep motor mapping. Preoperative motor deficits and diffusion-weighted imaging changes are predictors of permanent motor deficits in this setting.

OBJECTIVE Postoperative surgical site infections (SSIs) following brain tumor surgery frequently necessitate wound revision and bone flap removal. However, data on subsequent cranial reconstruction in this context remain limited. The aim of this study was to characterize patients undergoing bone flap removal due to SSI, determine the proportion who proceed to cranioplasty, and evaluate surgical strategies, complication rates, and risk factors for implant failure. METHODS In this multicenter observational study, patients who underwent bone flap removal due to SSI following brain tumor surgery from 2008 to 2022 at four Swedish neurosurgical centers were included. Clinical, radiological, and surgical data were collected retrospectively. Risk factors for implant removal were evaluated with logistic regression and Kaplan-Meier survival analyses. Functional outcome was assessed using the modified Rankin Scale (mRS). RESULTS Of 260 patients included in the analysis, 223 (86%, median age was 56 years) underwent cranioplasty and 37 (14%, median age 66 years) did not, primarily due to short life expectancy, poor medical condition, or wound concerns. Among patients who underwent cranioplasty, the most common tumor type was meningioma (75%) and the median cranial defect size was 35 cm2. Synthetic implants were used for all reconstructions. The overall implant removal rate was 21%, primarily due to wound dehiscence and infection. WHO grade 4 tumors and a cranial defect size > 64.5 cm2 were associated with an increased risk of implant removal (p < 0.05). Variables such as age, smoking, and diabetes did not predict complications. Functional outcome, as assessed by the mRS, remained unchanged postoperatively for most patients (87%). CONCLUSIONS Cranioplasty after bone flap removal due to SSI following brain tumor surgery was associated with a substantial risk of implant failure despite reconstruction of relatively small cranial defects. Predictive factors for implant failure were limited, suggesting that unmeasured variables, such as soft tissue conditions, might play a significant role in these procedures. Given the high rate of implant removal and limited survival among patients with high-grade tumors, careful patient selection and individualized decision-making are essential.

OBJECTIVE: While numerous studies have evaluated cranioplasty outcomes after decompressive craniectomy, most rely on heterogeneous cohorts with insufficient follow-up. The aim of this near-nationwide multicenter study was to review 15 years of cranial reconstructions in Sweden to establish the rates of complications and shunt dependence, as well as the extent of functional recovery, and to characterize the factors associated with these outcomes.

METHODS: Patients treated with primary cranioplasty after decompressive craniectomy from January 2008 to December 2022 were included. Patient medical records were reviewed for demographic and technical details, as well as surgical outcomes and shunt dependency. Functional recovery was determined before surgery and 6 months after cranioplasty using the modified Rankin Scale. Multivariable regression models (adjusted for confounders) were used to evaluate outcome predictors.

RESULTS: Among 725 patients (median age 49 years [IQR 33–59 years]) who underwent cranioplasty, autologous bone was used in 74%. The median follow-up duration was 80 months and 31% of patients underwent at least 1 reoperation. Long-term cranioplasty failure rates were significantly lower with synthetic implants, primarily due to a 15% revision rate caused by bone flap resorption in autologous cranioplasties. Resorption was most pronounced in patients younger than 40 years of age, while infection rates were comparable across different implant materials. One hundred patients (14%) received a permanent shunt, which was associated with the nature of the primary brain injury, cranial defect size, and external brain herniation prior to cranioplasty. Functional improvement was observed in 26% of patients following cranioplasty, and significantly more frequently in younger patients with fewer comorbidities, those who underwent earlier cranioplasty, and those with a history of malignant middle cerebral artery infarction or subarachnoid hemorrhage.

CONCLUSIONS: Cranioplasty outcomes after decompressive craniectomy were benchmarked and several outcome predictors were identified. Particularly, reoperation rates remain at alarming levels and suggest that a change in policy from an autograft- to alloplast-first strategy should be considered.

Background: This multi-centre study aimed to describe indications and outcomes in spontaneous supratentorial intracerebral haemorrhage (ICH) patients treated with decompressive craniectomy (DC).

Methods: All patients undergoing DC for spontaneous ICH at five Swedish neurosurgical centres between 2008 and 2022 were included (n = 45). Clinical, radiological, and outcome data were extracted. Outcome at six months was assessed using the modified Rankin Scale (mRS), dichotomized as favourable vs. unfavourable (mRS 0–3 vs. 4–6), and survival vs. mortality (mRS 0–5 vs. 6).

Results: Based on estimated ICH incidence, DC was performed in approximately 1.5 per 1000 cases. Median age was 47 years and the median ICH volume was 51 mL. Eighty-nine percent underwent ICH evacuation. DC performed as a primary procedure without ICP monitoring in 33%, whereas 67% underwent secondary DC due to refractory ICP elevation. Preoperative midline shift (median 11 mm) and basal cistern compression (present in 96%) significantly improved postoperatively (p < 0.001). Reoperation occurred in <10%. At follow-up, 28% were deceased and 40% had recovered favourably.

Conclusions: DC performed in a highly selected ICH population resulted in significant mass effect reduction and a relatively high rate of favourable outcome. Patient selection remains crucial but challenging, and larger prospective studies are warranted.

Background: Cerebral venous sinus thrombosis (CVT) is a rare condition that, in severe cases, can cause refractory intracranial hypertension. Despite limited evidence, decompressive craniectomy (DC) is endorsed as a rescue treatment. We aimed to describe indications, surgical characteristics, and outcomes of DC for severe CVT in a near-nationwide Swedish cohort. Methods: This multicentre retrospective case-series included all CVT patients treated with DC (n = 13) at five Swedish neurosurgical centres between 2008–2022. Demographic, clinical, radiological, and surgical variables, and six-month modified Rankin Scale (mRS) were extracted from medical records and radiological imaging. Favourable outcome was defined as mRS 0–3. Results: Median age was 53 years (IQR 32–62), and 77% were female. At admission, the median GCS Motor score (GCS M) was 6 (5–6) and all patients had reactive pupils. Preoperatively, GCS M declined to 5 (1–5), and only 46% had reactive pupils. Midline shift was 9 mm (6–11) and all patients had compressed basal cisterns before DC. Postoperatively, midline shift decreased to 2 mm (0–5), and basal cisterns were open in 85% of cases. Eleven patients (85%) developed external brain herniation, one patient (8%) had subdural hygroma requiring surgery, and 4 (31%) developed a postoperative intracranial haematoma, one of which (8%) was evacuated. No postoperative infections or reoperations due to DC-extension occurred. At follow-up, 62% had recovered favourably, while 15% were deceased. Conclusions: DC was an effective last-tier treatment of intracranial hypertension in selected severe CVT cases. Most patients recovered favourably, with low mortality and complication rates.

Background: Decompressive craniectomy (DC) is a last-resort treatment for severe traumatic brain injury (TBI) with refractory intracranial hypertension. Randomized controlled trials (RCTs) report mixed and sometimes conflicting results, leaving uncertainties regarding indications, timing, and long-term benefits. This study explored DC practices and outcomes in a contemporary Swedish setting contextualised in modern RCT evidence.

Methods: This retrospective multicentre study included 299 TBI patients who underwent DC between 2008 and 2022 across four Swedish neurosurgical centres. Clinical, radiological, surgical, and outcome data (6-months Glasgow Outcome Scale) were collected. Differences across centres and between adults/children were analysed.

Results: Annual DC rate remained stable over 15 years, modestly declining from 3.6 to 3.2 per million inhabitants. Significant regional differences were observed in timing, indications, and techniques. Proportion of primary versus secondary DC and surgery timing remained unchanged, though bifrontal DC decreased. Patients were young (median age 37), predominantly male (76%), severely injured (GCS M < 6), and 48% had unreactive pupils. Radiological improvement in mass effect post-DC (midline shift, basal cisterns) was significant (p < 0.001). Re-operation for haemorrhage occurred in 10%, complementary decompression, surgical-site infection, and subdural hygroma each occurred in ~ 5%. At 6 months, 60% had unfavourable outcomes and 11% were deceased. Higher age, lower GCS, comorbidities, impaired pupillary reactivity and obliterated basal cisterns independently predicted unfavourable outcome.

Conclusions: Landmark RCTs appear to have had limited influence on Swedish DC practice, which remains variable across centres. Real-world outcomes were more favourable than in recent RCTs and other acute brain injuries.

OBJECTIVE: Iatrogenic ischemic injury is believed to be one of the major causes of postoperative neurological deterioration after resection for diffuse low-grade glioma (dLGG). Epidemiological data on ischemic injury following glioma surgery are limited. The aim of this study was to explore the incidence of postoperative ischemia in a population-based cohort and investigate any correlation with postoperative neurological deterioration.

METHODS: In this retrospective study, ischemic lesions following dLGG resections, performed at 9 hospitals in Sweden and Norway between 2012 and 2017, were identified on diffusion-weighted MRI and volumetrically segmented. The association between the incidence, size, or type of ischemic lesion (rim lesions, limited to the resection border, or sector lesions, extending further into the brain tissue) and postoperative neurological deficits was analyzed.

RESULTS: A total of 286 patients were eligible for study inclusion. A postoperative ischemic lesion was found in 245 (85.7%) cases. In 87 (30.4%) patients, lesions were classified as the rim type; 158 (55.2%) patients had the sector type. Larger ischemic lesions were observed among patients with permanent major deficits (4.2 vs 1.6 cm3, p = 0.022). Sector-shaped ischemic lesions were more often associated with transient neurological deterioration than the rim lesions. The use of advanced imaging, intraoperative monitoring, or other specific neurosurgical techniques and tools did not affect the incidence of ischemic lesions.

CONCLUSIONS: The authors found postoperative ischemic lesions to be common after the resection of dLGG. Large and sector-shaped, but not rim-shaped, lesions were associated with measured postoperative neurological deficits. Preventing or limiting the extent of these ischemic injuries is important for improving functional results in dLGG surgery.

Background: Malignant middle cerebral artery infarction (MMI) can cause life-threatening edema with high mortality rates. Randomized controlled trials (RCTs) have shown that decompressive hemicraniectomy (DC) can improve survival rate and functional outcome in selected MMI patients. However, real-world outcomes are less well described.

Objective: To investigate DC indications, timing, and outcomes in MMI patients treated at 4 Swedish neurosurgical centers and the degree of alignment of real-world patient selection with eligibility criteria from 2 landmark RCTs–DESTINY I & II.

Methods: This retrospective, Swedish multicenter (n = 4) cohort study included 335 MMI patients treated with DC between 2008 and 2022. Demographics, clinical and radiological status, surgical factors, and 6-month outcomes (modified Rankin Scale [mRS]) were collected and compared across centers and with DESTINY trials.

Results: Median age was 55 (48–61) years, and 75% were male. Pre-DC, median Glasgow Coma Scale Motor score was 5 (5–6) and Charlson Comorbidity Index score was 3 (3–4). DC was performed at a median of 38 (25–56) hours from stroke onset. Median mRS at 6 months was 4 (4–5), 24% had mRS ≤ 3, and mortality was 17%. Only 19% and 12% of patients would have qualified for DESTINY I and II trials, respectively.

Conclusions: Indication and timing of DC as a treatment of MMI demonstrated notable discrepancies in surgical practice across centers and compared to landmark RCTs. However, despite differences in timing and indications for DC, the outcome did not differ significantly across centers. Our findings provide insight into the outcome of DC performed for MMI outside the strict criteria supported by level 1 evidence.

Background: Malignant middle cerebral artery infarction (MMI) is a severe condition caused by space-occupying brain edema due to ischemia. While decompressive hemicraniectomy (DC) improves outcome, many survivors experience lasting disabilities, and tools to predict outcome are lacking. We aimed to identify independent predictors of outcome following DC in MMI and to create a pragmatic, bedside tool for patient prognostication.

Methods: This retrospective, multicenter study analyzed 318 MMI patients treated with DC at 4 Swedish university hospitals (2008–2022). Demographic, preoperative, and postoperative variables were collected from medical records. Six-month modified Rankin Scale (mRS) was the primary endpoint, with favorable outcome defined as mRS 0–3. Univariable and multivariable ordinal logistic regressions were employed to identify independent predictors of mRS. Significant independent preoperative variables were included in the malignant middle cerebral artery infarction DC (MAD) score.

Results: Median age was 56 (interquartile range: 48–61) years; 75% were male. At 6 months, median mRS was 4 (4–5), 24% achieved favorable outcome, and 17% were deceased. MAD score assigned 1 point to each independent preoperative predictor of worse outcome: higher age (≥ 60 years), female sex, lower Glasgow Coma Scale Motor score (< 4), and impaired pupillary reactivity (all P ≤ 0.03). MAD-stratified outcome, ordered from 0 to 4 points, was 32%, 25%, 15%, 0%, and 0% (favorable outcome) and 9%, 16%, 23%, 40%, and 100% (mortality).

Conclusions: A large proportion of MMI patients recover unfavorably following DC. The presented MAD score was an internally reliable prognostic tool for MMI patients treated with DC. External validity of MAD and predictive value of female sex should be further explored.

Patients with severe brain injury requiring decompressive craniectomy are at increased risk of developing chronic hydrocephalus, often necessitating both cranioplasty and shunt surgery. The optimal sequence of these procedures remains unclear, with limited and conflicting evidence on associated complication rates and outcomes. The aim of this study was to investigate clinical practices and outcomes associated with 3 procedural sequences: (1) cranioplasty before shunt, (2) simultaneous cranioplasty and shunt, and (3) shunt before cranioplasty.

METHODS: – In this multicenter retrospective cohort study, 99 patients from 4 Swedish neurosurgical centers who underwent both cranioplasty and shunt surgery over 15 years (2008-2022; only the first 10 years at 1 center) were included. Clinical data, surgical details, complications, and functional outcomes (modified Rankin Scale) were analyzed by each sequence group.

RESULTS: – Of 99 patients, 37 (37%) underwent cranioplasty before shunt, 37 (37%) had simultaneous procedures, and 25 (25%) received a shunt before cranioplasty. There was no significant difference in complications rates after cranioplasty or shunt surgery between these groups (P > .05). However, shunt before cranioplasty was associated with slightly higher rates of shunt complications (36% revision) but lower rates of cranioplasty removal (8%), whereas the inverse pattern was observed in the cranioplasty before shunt group (24% shunt revision; 30% cranioplasty removal). There was no difference in functional outcomes before or after cranioplasty or shunt surgery between the groups (P > .05).

CONCLUSION: – The sequence of cranioplasty and shunt surgery did not significantly influence overall risks of implant revision or functional outcome, although complication patterns and their clinical severity differed between approaches. Cranioplasty implant removal remains a particularly serious event, while shunt infections can be equally detrimental. Future studies should refine sequencing strategies considering hydrocephalus type, timing, and procedural factors to minimize risk and improve patient outcomes.