Intraoperative Transcranial Motor-Evoked Potentials Predict Motor Function Outcome in Intracerebral Hemorrhage Surgery

Motor Evoked Potential Warning Criteria in Supratentorial Surgery: A Scoping Review

During intraoperative monitoring of motor evoked potentials (MEP), heterogeneity across studies in terms of study populations, intraoperative settings, applied warning criteria, and outcome reporting exists. A scoping review of MEP warning criteria in supratentorial surgery was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). Sixty-eight studies fulfilled the eligibility criteria. The most commonly used alarm criteria were MEP signal loss, which was always a major warning sign, followed by amplitude reduction and threshold elevation. Irreversible MEP alterations were associated with a higher number of transient and persisting motor deficits compared with the reversible changes. In almost all studies, specificity and Negative Predictive Value (NPV) were high, while in most of them, sensitivity and Positive Predictive Value (PPV) were rather low or modest. Thus, the absence of an irreversible alteration may reassure the neurosurgeon that the patient will not suffer a motor deficit in the short-term and long-term follow-up. Further, MEPs perform well as surrogate markers, and reversible MEP deteriorations after successful intervention indicate motor function preservation postoperatively. However, in future studies, a consensus regarding the definitions of MEP alteration, critical duration of alterations, and outcome reporting should be determined.

Modified behavioural tests to detect white matter injury- induced motor deficits after intracerebral haemorrhage in mice

Motor function deficit induced by white matter injury (WMI) is one of the most severe complications of intracerebral haemorrhage (ICH). The degree of WMI is closely related to the prognosis of patients after ICH. However, the current behavioural assessment of motor function used in the ICH mouse model is mainly based on that for ischaemic stroke and lacks the behavioural methods that accurately respond to WMI. Here, a series of easy-to-implement behavioural tests were performed to detect motor deficits in mice after ICH. The results showed that the grip strength test and the modified pole test not only can better distinguish the degree of motor dysfunction between different volumes of blood ICH models than the Basso Mouse Scale and the beam walking test but can also accurately reflect the severity of WMI characterized by demyelination, axonal swelling and the latency of motor-evoked potential delay induced by ICH. In addition, after ICH, the results of grip tests and modified pole tests, rather than the Basso Mouse Scale and the beam walking test, were worse than those observed after intraventricular haemorrhage (IVH), which was used as a model of brain haemorrhage in non-white matter areas. These results indicate that the grip strength test and the modified pole test have advantages in detecting the degree of motor deficit induced by white matter injury after ICH in mice.

Efficacies of minimally invasive puncture and small bone window craniotomy for hypertensive intracerebral hemorrhage, evaluation of motor-evoked potentials and comparison of postoperative rehemorrhage between the two methods

Application value of the minimally invasive puncture and small bone window craniotomy in hypertensive intracerebral hemorrhage was investigated to explore the effects of the above treatment methods on motor-evoked potentials (MEPs) and postoperative rehemorrhage. Patients with hypertensive intracerebral hemorrhage who were admitted to Chengyang People's Hospital from March 2016 to December 2017 were selected and randomly divided into the minimally invasive group (n=40) and the craniotomy group (n=40). The minimally invasive group was treated with minimally invasive puncture and drainage for hematomas, while the craniotomy group received small bone window craniotomy for evacuation of hematomas. The clinical efficacy was compared between the two groups. At 28 days after operation, the Chinese scale of clinical neurological deficit of stroke patients (CSS) score in the minimally invasive group was lower than that in the craniotomy group (p<0.05). At 28 days after operation, the S-100β level in the minimally invasive group was lower than that in the craniotomy group (p<0.05). At 1 week after operation, 35 patients in the minimally invasive group were able to elicit MEP waveforms, and only 7 patients in the craniotomy group were able to elicit positive waveforms. At 2 weeks after operation, 40 patients in the minimally invasive group and 20 patients in the craniotomy group could elicit MEP waveforms, and the incubation period, central motor conduction time and amplitude in the former were significantly better than those in the latter (p<0.05). The operation time and length of hospital stay were shorter with more total expenses of hospitalization in the minimally invasive group compared to those in the craniotomy group (p<0.05). Compared with small bone window craniotomy, minimally invasive puncture can reduce serum S-100β level. Its advantages are obvious, so it is worthy of promotion and application.

Development and validation of the hypertensive intracerebral hemorrhage prognosis models

To develop and validate the prognosis model of hypertensive intracerebral hemorrhage based on admission characteristics, which would be applied to predict the 3-month outcome.For developing the prognosis models, we studied data from 325 patients with retrospectively consecutive hypertensive intracerebral hemorrhage admitted between 2012 and 2016. The predictive value of admission characteristics was tested in logistic regression models, presenting 3-month outcome as the primary outcome. The performance of the models was tested by discrimination and calibration. After development, internal and external validations were used to test the function.The multivariate analysis of logistic regression indicated that age, Glasgow coma scale score, pupillary light reflex, hypoxemia, intracerebral hemorrhage volume, blood glucose, and D-dimer level were independent factors of the hypertensive intracerebral hemorrhage prognosis model. The prognosis model based on those admission risk factors worked well. The receiver operating characteristic curve was used to analyze the discriminant ability of model A, model A + B, and model A + B + C. Specifically, the area under the receiver operating characteristic curve increased from 0.816 (model A; 95% CI, 0.760-0.872) to 0.913 (model A + B + C; 95% CI, 0.881-0.946), and the models were not overoptimistic and were applicably confirmed by internal and external validations respectively.This prognosis model could be used to predict the prognosis of patients with hypertensive intracerebral hemorrhage early, simply and accurately, contributing to the clinical treatment eventually.

Management of Spontaneous Intracerebral Hematoma

The incidence of spontaneous intracerebral hematoma (SICH) is even now high worldwide, especially higher in Japan than in Western countries, despite the development of advances in blood pressure (BP) management and food/alcohol intake education. Although mortality and morbidity for SICH are high, some controversies remain regarding the appropriate acute phase of treatment. Recent studies have revealed that BP lowering treatment than 140 mmHg resulted in better outcomes. However the efficacy of surgical treatment for SICH has not been well established, with the exception of that for cerebellar SICH over 3 cm in diameter and life-saving procedures, although many randomized control studies and systematic reviews focused on surgical treatment have been reported. In this review, we summarize some issues and discuss strategies in development for the treatment of SICH.