Malignant MCA infarction

Decompressive craniectomy
In patients under age 60, performance of a decompressive craniectomy in appropriate patients with large hemispheric infarction who deteriorate due to mass effect within 48 hours is a Neurocritical Care Society Clinical Performance Measure.

Risk factors
Overall risk factors include
 * History
 * Congestive heart failure
 * Hypertension
 * Absence of prior stroke
 * No acute stroke intervention
 * Exam
 * Higher NIHSS
 * Decreased level of consciousness
 * Visual field deficits
 * Closed eyes
 * Vomiting
 * Labs
 * WBCs >10,000/μL
 * Glucose >145 or >150
 * Imaging
 * Involvement of >50% of MCA territory
 * Involvement of additional vascular territories
 * Susceptibility vessel sign of M1
 * Hyperdense MCA sign
 * CT ASPECTS > 7
 * DWI ASPECTS ≤ 3
 * DWI lesion volume >82 mL with 6 hours of onset or >145 mL within 14 hours of onset
 * Basil cistern effacement
 * Midline shift
 * Collateral score < 2

Risk scoring
Several risk scores have been developed to predict the likelihood of developing cerebral edema. The Kasner et al. Index Score was the first one developed in 2001, had a lower AUC of some others, and has not been externally validated. The DASH score developed in 2014 has a high AUC of 0.88 but requires MRI which is frequently not available. Most recently, the E-score was developed on a large group of 572 patients and had AUC of 0.78, but the outcome definition of edema used to calculate the score was poorly defined. The TURN score was originally developed form predicting hemorrhage after thrombolysis, but it has a low AUC of 0.67.

The MBE score developed in 2017 has a high AUC of 0.88 but was only developed on 121 patients and has not been externally validated, but it is reasonable. The EDEMA score is the most validated at this time. It was developed on 222 patients and in 2020 was externally validated on another 478 patients, with AUC of 0.72-0.76, and used a clinically important definition of edema, being patients that died or required hemicraniectomy with significant midline shift.

Kasner et al. Index Score (2001)
This score was developed in 201 patients to predict the probability of fatal brain edema after malignant MCA infarction. AUC is 0.7, which makes it less discriminating than other scores.

DASH score (2014)
This score was developed in 119 patients. It requires MRI but has a high AUC (C-statistic) of 0.88.

MBE score (2017)
This score was developed in 121 patients and utilizes four criteria to predict malignant brain edema (sulcal effacement, compression of the lateral ventricle, midline shift >5 mm, and neurological deterioration of NIHSS increase by >2 points and decrease in level of consciousness so that item 1A of NIHSS to ≥1). AUC (C-statistic) = 0.88.

TURN score (2016)
This score was originally developed to predict ICH after tPA, but also predicts edema after IV tPA administration. However the "brain-swelling" measure utilized is nebulous and the AUC was only 0.69, so this score is not as valuable as several others. It utilizes baseline NIHSS and prestroke mRS as its only parameters.

EDEMA score (2017)
The Enhanced Detection of Edema in Malignant Anterior Circulation Stroke (EDEMA) score was published in 2017 as a tool to predict the risk of malignant cerebral edema (defined as death with midline shift ≥5 or decompressive craniectomy) with a total area under the curve (AUC) of 0.76. An external validation study in Chinese patients showed a similar AUC of 0.72. By adding NIHSS, the EDEMA score can have an improved AUC of 0.83, and this may be better for physicians with a threshold probability of intervention of 60% or less.

E-score (2019)
This score was developed in 572 ischemic stroke patients and has an AUC of 0.78 for developing cerebral edema (defined as mass effect with compression of lateral ventricles, with or without midline shift).

Mortality
In one longitudinal study of 1,841 patients in France who underwent decompressive craniectomy for malignant MCA infarction, 86.2% were alive at 1 week, 79.85% were alive at 1 month, 75.29% were alive at 6 months, 74.31% were alive at 1 year, and 73.28% were alive at 2 years.

Patient factors at time of craniectomy

 * Poor prognostic factors
 * Male gender: HR 1.22 (95% CI 1.01-1.46) for 5 year mortality
 * Good prognostic factors
 * Age < 60 years: HR 0.53 (95% CI 0.43-0.64) for 5 year mortality
 * Center with high surgical activity: HR 0.74 (95% CI 0.62-0.89) for 5 year mortality
 * Craniectomy within 24-48 hours
 * Aphasia
 * Hemiplegia
 * Normal consciousness at time of surgery: HR 0.6 (95% CI 0.5-0.74) for 5 year mortality

Lab values

 * Caspase 3: elevated serum levels (>0.17 ng/mL) in one study were 94% sensitive and 71% specific for mortality, with AUC 88%, positive predictive value of 75%, and negative predict value of 92%. aOR for mortality was 51.25 (95% CI 8.30-316.31).

Ethics
Our biases should not prevent us from appropriately treating patients.