Surgical decompression for cerebral oedema in acute ischaemic stroke

Surgical decompression for malignant cerebral oedema after ischaemic stroke

BACKGROUND

Large territory middle cerebral artery (MCA) ischaemic strokes account for around 10% of all ischaemic strokes and have a particularly devastating prognosis when associated with malignant oedema. Progressive cerebral oedema starts developing in the first 24 to 48 hours of stroke ictus with an associated rise in intracranial pressure. The rise in intracranial pressure may eventually overwhelm compensatory mechanisms leading to a cascading secondary damage to surrounding unaffected parenchyma. This downward spiral can rapidly progress to death or severe neurological disability. Early decompressive craniectomy to relieve intracranial pressure and associated tissue shift can help ameliorate this secondary damage and improve outcomes. Evidence has been accumulating of the benefit of early surgical decompression in stroke patients. Earlier studies have excluded people above the age of 60 due to associated poor outcomes; however, newer trials have included this patient subgroup. This review follows a Cochrane Review published in 2012.

OBJECTIVES

To assess the effectiveness of surgical decompression in people with malignant oedema after ischaemic stroke with regard to reduction in mortality and improved functional outcome. We also aimed to examine the adverse effects of surgical decompression in this patient cohort.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL; 2022, Issue 7 of 12), MEDLINE Ovid, Embase Ovid, Web of Science Core Collection, Scopus databases, ClinicalTrials.gov, and the WHO ICTRP to July 2022. We also reviewed the reference lists of relevant articles.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing decompressive craniectomy with medical management to best medical management alone for people with malignant cerebral oedema after MCA ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results, assessed study eligibility, performed risk of bias assessment, and extracted the data. The primary outcomes were death and death or severe disability (modified Rankin Scale (mRS) > 4) at 6 to 12 months follow-up. Other outcomes included death or moderate disability (mRS > 3), severe disability (mRS = 5), and adverse events. We assessed the certainty of the evidence using the GRADE approach, categorising it as high, moderate, low, or very low.

MAIN RESULTS

We included nine RCTs with a total of 513 participants included in the final analysis. Three studies included patients younger than 60 years of age; two trials accepted patients up to 80 years of age; and one trial only included patients 60 years or older. The majority of included trials (six) mandated a time from stroke ictus to treatment of < 48 hours, whilst in two of them this was < 96 hours. Surgical decompression was associated with a reduction in death (odds ratio (OR) 0.18, 95% confidence interval (CI) 0.12 to 0.27, 9 trials, 513 participants, P < 0.001; high-certainty evidence); death or severe disability (mRS > 4, OR 0.22, 95% CI 0.15 to 0.32, 9 trials, 513 participants, P < 0.001; high-certainty evidence); and death or moderate disability (mRS > 3, OR 0.34, 95% CI 0.22 to 0.52, 9 trials, 513 participants, P < 0.001; moderate-certainty evidence). Subgroup analysis did not reveal any significant effect on treatment outcomes when analysing age (< 60 years versus ≥ 60 years); time from stroke ictus to intervention (< 48 hours versus ≥ 48 hours); or dysphasia. There was a significant subgroup effect of time at follow-up (6 versus 12 months, P = 0.02) on death as well as death or severe disability (mRS > 4); however, the validity of this finding was affected by fewer participant numbers in the six-month follow-up subgroup. There was no consistent reporting of per-participant adverse event rates in any of the included studies, which prevented further analysis.

AUTHORS' CONCLUSIONS

Surgical decompression improves outcomes in the management of malignant oedema after acute ischaemic stroke, including a considerable reduction in death or severe disability (mRS > 4) and a reduction in death or moderate disability (mRS > 3). Whilst there is evidence that this positive treatment effect is present in patients > 60 years old, it is important to take into account that these patients have a poorer prospect of functional survival independent of this treatment effect. In interpreting these results it must also be considered that the data demonstrating benefit are drawn from a unique patient subset with profound neurological deficit, reduced level of consciousness, and no pre-morbid disability or severe comorbidity.

Intracranial pressure elevation after ischemic stroke in rats: cerebral edema is not the only cause, and short-duration mild hypothermia is a highly effective preventive therapy

In both the human and animal literature, it has largely been assumed that edema is the primary cause of intracranial pressure (ICP) elevation after stroke and that more edema equates to higher ICP. We recently demonstrated a dramatic ICP elevation 24 hours after small ischemic strokes in rats, with minimal edema. This ICP elevation was completely prevented by short-duration moderate hypothermia soon after stroke. Here, our aims were to determine the importance of edema in ICP elevation after stroke and whether mild hypothermia could prevent the ICP rise. Experimental stroke was performed in rats. ICP was monitored and short-duration mild (35 °C) or moderate (32.5 °C) hypothermia, or normothermia (37 °C) was induced after stroke onset. Edema was measured in three studies, using wet-dry weight calculations, T2-weighted magnetic resonance imaging, or histology. ICP increased 24 hours after stroke onset in all normothermic animals. Short-duration mild or moderate hypothermia prevented this rise. No correlation was seen between ΔICP and edema or infarct volumes. Calculated rates of edema growth were orders of magnitude less than normal cerebrospinal fluid production rates. These data challenge current concepts and suggest that factors other than cerebral edema are the primary cause of the ICP elevation 24 hours after stroke onset.

Outcome after decompressive craniectomy in patients with dominant middle cerebral artery infarction: A preliminary report

Introduction:

Life-threatening, space occupying, infarction develops in 10-15% of patients after middle cerebral artery infarction (MCAI). Though decompressive craniectomy (DC) is now standard of care in patients with non-dominant stroke, its role in dominant MCAI (DMCAI) is largely undefined. This may reflect the ethical dilemma of saving life of a patient who may then remain hemiplegic and dysphasic. This study specifically addresses this issue.

Materials and Methods:

This retrospective analysis studied patients with DMCAI undergoing DC. Patient records, operation notes, radiology, and out-patient files were scrutinized to collate data. Glasgow outcome scale (GOS), Barthel index (BI) and improvement in language and motor function were evaluated to determine functional outcome.

Results:

Eighteen patients between 22 years and 72 years of age were included. 6 week, 3 month, 6 month and overall survival rates were 66.6% (12/18), 64% (11/17), 62.5% (10/16) and 62.5% (10/16) respectively. Amongst ten surviving patients with long-term follow-up, 60% showed improvement in GOS, 70% achieved BI score >60 while 30% achieved full functional independence. In this group, motor power and language function improved in 9 and 8 patients respectively. At last follow-up, 8 of 10 surviving patients were ambulatory with (3/8) or without (5/8) support. Age <50 years corresponded with better functional outcome amongst survivors (P value –0.0068).

Conclusion:

Language and motor outcomes after DC in patients with DMCAI are not as dismal as commonly perceived. Perhaps young patients (<50 years) with DMCAI should be treated with the same aggressiveness that non-DMCAI is currently dealt with.

Decompressive craniectomy: past, present and future

Decompressive craniectomy (DC)--a surgical procedure that involves removal of part of the skull to accommodate brain swelling--has been used for many years in the management of patients with brain oedema and/or intracranial hypertension, but its place in contemporary practice remains controversial. Results from a recent trial showed that early (neuroprotective) DC was not superior to medical management in patients with diffuse traumatic brain injury. An ongoing trial is investigating the clinical and cost effectiveness of secondary DC as a last-tier therapy for post-traumatic refractory intracranial hypertension. With regard to ischaemic stroke (malignant middle cerebral artery infarction), a recent Cochrane review concluded that DC improves survival compared with medical management, but that a higher proportion of DC survivors experience moderately severe or severe disability. Although many patients have a good outcome, the issue of DC-related disability raises important ethical issues. As DC and subsequent cranioplasty are associated with a number of complications, indiscriminate use of this surgery is not appropriate. Here, we review the evidence and present considerations regarding surgical technique, ethics and cost-effectiveness of DC. Prospective clinical trials and cohort studies are essential to enable optimization of patient care and outcomes.

Customized cranioplasty implants using three-dimensional printers and polymethyl-methacrylate casting

Objective

The prefabrication of customized cranioplastic implants has been introduced to overcome the difficulties of intra-operative implant molding. The authors present a new technique, which consists of the prefabrication of implant molds using three-dimensional (3D) printers and polymethyl-methacrylate (PMMA) casting.

Methods

A total of 16 patients with large skull defects (>100 cm²) underwent cranioplasty between November 2009 and April 2011. For unilateral cranial defects, 3D images of the skull were obtained from preoperative axial 1-mm spiral computed tomography (CT) scans. The image of the implant was generated by a digital subtraction mirror-imaging process using the normal side of the cranium as a model. For bilateral cranial defects, precraniectomy routine spiral CT scan data were merged with postcraniectomy 3D CT images following a smoothing process. Prefabrication of the mold was performed by the 3D printer. Intraoperatively, the PMMA implant was created with the prefabricated mold, and fit into the cranial defect.

Results

The median operation time was 184.36±26.07 minutes. Postoperative CT scans showed excellent restoration of the symmetrical contours and curvature of the cranium in all cases. The median follow-up period was 23 months (range, 14-28 months). Postoperative infection was developed in one case (6.2%) who had an open wound defect previously.

Conclusion

Customized cranioplasty PMMA implants using 3D printer may be a useful technique for the reconstruction of various cranial defects.

Surgical decompression for cerebral oedema in acute ischaemic stroke

BACKGROUND

Large cerebral infarction has a high case fatality. Despite the use of conventional medical treatments such as hyperventilation, mannitol, diuretics, corticosteroids and barbiturates, the outcome of this condition remains poor. Decompressive surgery to relieve intracranial pressure is performed in some cases, although evidence of any clinical benefits has not been available until recently. This is an update of a Cochrane review first published in 2002.

OBJECTIVES

To examine the effects of decompressive surgery in patients with massive acute ischaemic stroke complicated with cerebral oedema, and to judge whether decompressive surgery is effective in improving survival or survival free of severe disability.

SEARCH METHODS

We searched the Cochrane Stroke Group's Trials Register (last searched October 2010), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 7), MEDLINE (1966 to October 2010), EMBASE (1980 to October 2010) and Science Citation Index (October 2010). We also searched the reference lists of all relevant articles.

SELECTION CRITERIA

Randomised controlled studies of decompressive surgery plus medical treatment versus medical treatment alone in patients with clinically and radiologically confirmed cerebral infarcts complicated with cerebral oedema.

DATA COLLECTION AND ANALYSIS

One author assessed the titles and retrieved the relevant studies. The same author extracted data, with discussion among all authors for clarification. Outcomes were death at the end of follow-up, death or disability defined as the modified Rankin Scale (mRS) > 3 at the end of follow-up, death or severe disability defined as mRS > 4 at 12 months and disability defined as mRS 4 or 5 at 12 months. The results are given using the Peto odds ratio (Peto OR) with 95% confidence intervals (CIs).

MAIN RESULTS

We included three trials in this review, involving 134 patients who were 60 years of age or younger. The time window for the intervention was 30 hours from stroke onset in two studies and 96 hours in one study. All trials were stopped early. Surgical decompression reduced the risk of death at the end of follow-up (OR 0.19, 95% CI 0.09 to 0.37) and the risk of death or disability defined as mRS > 4 at 12 months (OR 0.26, 95% CI 0.13 to 0.51). Death or disability defined as mRS > 3 at the end of follow-up was no different between the treatment arms (OR 0.56, 95% CI 0.27 to 1.15).

AUTHORS' CONCLUSIONS

Surgical decompression lowers the risk of death and death or severe disability defined as mRS > 4 in selected patients 60 years of age or younger with a massive hemispheric infarction and oedema. Optimum criteria for patient selection and for timing of decompressive surgery are yet to be defined. Since survival may be at the expense of substantial disability, surgery should be the treatment of choice only when it can be assumed, based on their preferences, that it is in the best interest of patients. Since all the trials were stopped early, an overestimation of the effect size cannot be excluded.

Cranioplasty using polymethyl methacrylate prostheses

In this retrospective study we attempted to assess the clinical performance of prefabricated polymethyl methacrylate (PMMA) prostheses and to determine whether they outperform intra-operatively moulded PMMA prostheses in reducing operating time, blood loss and surgical complications in elective delayed cranioplasty operations, after decompressive craniectomy, to repair large (> 100 cm2) cranial defects. Patients (n=131) were divided into three groups according to the cranioplasty technique used. Group 1 patients received fresh frozen autograft bone that had been removed at the craniectomy and refrigerated at -80 degrees C. Group 2 included patients whose PMMA prosthesis was moulded intra-operatively. Group 3 patients received a custom-made prefabricated PMMA prosthesis manufactured using computer-aided design/computer-aided manufacturing (CAD/CAM). Group 2 patients required significantly more operating time than both group 1 (p<0.001) and group 3 (p<0.001) patients, but operating time did not differ significantly between groups 1 and 3 (p>0.05). Mean intra-operative blood loss was significantly higher in group 2 than in group 1 (p=0.015) but did not differ significantly between group 1 and group 3 (p>0.05). The infection rate associated with prefabricated PMMA prostheses was lower than that for intra-operatively moulded PMMA prostheses and was comparable to that for autograft bone flaps. A CAD/CAM PMMA prosthesis is an excellent alternative when no autogenous bone graft harvested during craniectomy is available.

Decompressive craniectomy for hemispheric infarction: predictive factors for six month rehabilitation outcome

BACKGROUND

Decompressive craniectomy after hemispheric infarction has been shown to reduce mortality and functional outcome in selected patients. However, the optimal timing for surgery and patient most likely to benefit from this procedures was not known. We aimed to determine possible factors predictive of outcome following decompressive craniectomy for ischemic infarction from review of oneurological outcome in our patients at six months.

METHODS

We retrospectively reviewed 21 patients who underwent decompressive craniectomy for hemispheric infarction over a three year period in a regional neurosurgical center in Hong Kong. All patients were recruited subsequently for active in-patient rehabilitation, when suitable.

FINDINGS

The median age was 53 and the male to female ration was 1:3. Four patients (19%) achieved independent activity of daily living at six months after rehabilitation. Neither early surgery, within 24-48 hours after admission, nor side of infarction correlated with six month neurological outcome. All four patients with favourable neurological outcome at six month demonstrated favourable clinical improvement even at one month.

CONCLUSIONS

Early decompressive hemicraniectomy is not predictive of neurological outcome, determined by Glasgow outcome score, at six months (P = 1.00, NS).

Craniectomia descompressiva para tratamento de hipertensão intracraniana secundária a infarto encefálico isquêmico extenso: análise de 34 casos

Infarto encefálico isquêmico extenso (IEIE) é a perda do suprimento sangüíneo de uma grande área cerebral, principalmente do território da artéria cerebral média. Pode evoluir com edema importante, hipertensão intracraniana e óbito em até 80% dos casos. OBJETIVO: Avaliar os resultados da craniectomia descompressiva no tratamento da hipertensão intracraniana secundária ao IEIE, comparando com os resultados de outros estudos publicados na literatura. MÉTODO: Foram analisados 34 pacientes com IEIE tratados clinicamente sem sucesso e que necessitaram de craniectomia descompressiva para controle da hipertensão intracraniana. RESULTADOS: 8 pacientes (23,52%) faleceram, 26 (76,47%) sobreviveram, sendo que 2 (7,70%) permaneceram em estado vegetativo. CONCLUSÃO: Os fatores idade acima de 50 anos e sexo masculino se associaram a maior risco de evolução para óbito. O nível de consciência à admissão e a área do retalho ósseo apresentaram valores próximos de significância estatística.

Early decompressive surgery in malignant infarction of the middle cerebral artery: a pooled analysis of three randomised controlled trials

BACKGROUND

Malignant infarction of the middle cerebral artery (MCA) is associated with an 80% mortality rate. Non-randomised studies have suggested that decompressive surgery reduces this mortality without increasing the number of severely disabled survivors. To obtain sufficient data as soon as possible to reliably estimate the effects of decompressive surgery, results from three European randomised controlled trials (DECIMAL, DESTINY, HAMLET) were pooled. The trials were ongoing when the pooled analysis was planned.

METHODS

Individual data for patients aged between 18 years and 60 years, with space-occupying MCA infarction, included in one of the three trials, and treated within 48 h after stroke onset were pooled for analysis. The protocol was designed prospectively when the trials were still recruiting patients and outcomes were defined without knowledge of the results of the individual trials. The primary outcome measure was the score on the modified Rankin scale (mRS) at 1 year dichotomised between favourable (0-4) and unfavourable (5 and death) outcome. Secondary outcome measures included case fatality rate at 1 year and a dichotomisation of the mRS between 0-3 and 4 to death. Data analysis was done by an independent data monitoring committee.

FINDINGS

93 patients were included in the pooled analysis. More patients in the decompressive-surgery group than in the control group had an mRS<or=4 (75%vs 24%; pooled absolute risk reduction 51% [95% CI 34-69]), an mRS<or=3 (43%vs 21%; 23% [5-41]), and survived (78%vs 29%; 50% [33-67]), indicating numbers needed to treat of two for survival with mRS<or=4, four for survival with mRS<or=3, and two for survival irrespective of functional outcome. The effect of surgery was highly consistent across the three trials.

INTERPRETATION

In patients with malignant MCA infarction, decompressive surgery undertaken within 48 h of stroke onset reduces mortality and increases the number of patients with a favourable functional outcome. The decision to perform decompressive surgery should, however, be made on an individual basis in every patient.

Clinical review: Therapy for refractory intracranial hypertension in ischaemic stroke

The treatment of patients with large hemispheric ischaemic stroke accompanied by massive space-occupying oedema represents one of the major unsolved problems in neurocritical care medicine. Despite maximum intensive care, the prognosis of these patients is poor, with case fatality rates as high as 80%. Therefore, the term 'malignant brain infarction' was coined. Because conservative treatment strategies to limit brain tissue shift almost consistently fail, these massive infarctions often are regarded as an untreatable disease. The introduction of decompressive surgery (hemicraniectomy) has completely changed this point of view, suggesting that mortality rates may be reduced to approximately 20%. However, critics have always argued that the reduction in mortality may be outweighed by an accompanying increase in severe disability. Due to the lack of conclusive evidence of efficacy from randomised trials, controversy over the benefit of these treatment strategies remained, leading to large regional differences in the application of this procedure. Meanwhile, data from randomised trials confirm the results of former observational studies, demonstrating that hemicraniectomy not only significantly reduces mortality but also significantly improves clinical outcome without increasing the number of completely dependent patients. Hypothermia is another promising treatment option but still needs evidence of efficacy from randomised controlled trials before it may be recommended for clinical routine use. This review gives the reader an integrated view of the current status of treatment options in massive hemispheric brain infarction, based on the available data of clinical trials, including the most recent data from randomised trials published in 2007.

Neuroprotection in malignant MCA infarction

Massive unilateral hemispheric infarction often develops progressive postischemic edema that leads to a malignant course of stroke with mortality of up to 80% with conventional medical therapies. Hypothermia and decompressive hemicraniectomy have shown neuroprotective effects in several animal models of focal transient and permanent MCA occlusion by reducing infarct size and improving neurological outcome. Our aim in this paper was to review the possible mechanisms of both therapies as well as the optimal time window and duration of application of each treatment in animal model and in human malignant MCA infarction reported in the literature.

The prediction of malignant cerebral infarction by molecular brain barrier disruption markers

BACKGROUND AND PURPOSE

Space-occupying brain edema is a life-threatening complication in patients with large hemispheric stroke. The aim of the study was to determine whether molecular markers of endothelial damage may help to predict secondary brain edema and, secondly, to identify patients who could benefit from aggressive therapies such as decompressive hemicraniectomy or hypothermia.

METHODS

We studied 40 consecutive patients with malignant middle cerebral artery (MCA) infarction and 35 controls with massive MCA infarctions <70 years of age and matched by stroke severity on admission. Cranial computed tomography (CT) was performed at entry and repeated between days 4 and 7, or earlier if there was neurological worsening. Malignant MCA (m-MCA) infarction was diagnosed when follow-up CT detected a more than two-thirds space-occupying MCA infarction with midline shift, compression of the basal cisterns, and neurological deterioration. Plasma concentrations of glutamate, glycine, gamma-aminobutyric acid, interleukin-6 (IL-6), IL-10, tumor necrosis factor-alpha, matrix metalloproteinase-9 (MMP-9), and cellular-fibronectin (c-Fn) were determined in blood samples obtained at admission.

RESULTS

Mean time from stroke onset to blood sampling was 6.3+/-4.8 in m-MCA and 7.7+/-6.0 hours in the control group (P=0.63). Baseline characteristics were comparable in both groups. c-Fn and MMP-9 levels were significantly higher in patients with m-MCA than in controls (all P<0.001). c-Fn >16.6 microg/mL had the highest sensitivity (90%), specificity (100%), and negative and positive predictive values (89% and 100%, respectively) for the prediction of m-MCA infarction.

CONCLUSIONS

A plasma c-Fn concentration >16.6 microg/mL at admission is associated with the development of m-MCA infarction with high sensitivity and specificity, suggesting that c-Fn might be useful in therapeutic decision making.

Is decompressive craniectomy for malignant middle cerebral artery infarction of any worth?

OBJECTIVE

Malignant middle cerebral artery (MCA) infarction is characterized by mortality rate of up to 80%. The aim of this study was to determine the value of decompressive craniectomy in patients presenting malignant MCA infarction compared with those receiving medical treatment alone.

METHODS

Patients with malignant MCA infarction treated in our hospital between January 1996 and March 2004 were included in this retrospective analysis. The National Institute of Health Stroke Scale (NIHSS) was used to assess neurological status on admission and at one week after surgery. All patients were followed up for assessment of functional outcome by the Barthel index (BI) and modified Rankin Scale (RS) at 3 months after infarction.

RESULTS

Ten out of 24 patients underwent decompressive craniectomy. The mean interval between stroke onset and surgery was 62.10 h. The mortality was 10.0% compared with 64.2% in patients who received medical treatment alone (P<0.001). The mean NIHSS score before surgery was 26.0 and 15.4 after surgery (P<0.001). At follow up, patients who underwent surgery had significantly better outcome with mean BI of 53.3, RS of 3.3 as compared to only 16.0 and 4.60 in medically treated patients. Speech function also improved in patients with dominant hemispherical infarction.

CONCLUSION

Decompressive craniectomy in patients with malignant MCA infarction improves both survival rates and functional outcomes compared with medical treatment alone. A randomized controlled trial is required to substantiate those findings.