Enlighten-Research publications by members of the University of Glasgow http://eprints.gla.ac.uk Minimally invasive surgery with thrombolysis in intracerebral haemorrhage evacuation (MISTIE III): a randomised, controlled, open-label phase 3 trial with blinded endpoint

This review provides a current perspective of invasive and noninvasive ICP measurements, along with a sense of their relative strengths, drawbacks and areas for further improvement. At present, none of the noninvasive methods demonstrates sufficient accuracy and ease of use while allowing continuous monitoring in routine clinical use. However, they provide a realizable ICP measurement in specific patients especially when invasive monitoring is contraindicated or unavailable. Among all noninvasive ICP measurement methods, ONSD and TCD are attractive and may be useful in selected settings though they cannot be used as invasive ICP measurement substitutes. For a sufficiently accurate and universal continuous ICP monitoring method/device, future research and developments are needed to integrate further refinements of the existing methods, combine telemetric sensors and/or technologies, and validate large numbers of clinical studies on relevant patient populations.

In light of these findings, the authors propose that quick-brain MR imaging replace CT scanning as the diagnostic modality of choice in examining and following shunt-treated patients because it offers significant advantages.

BACKGROUND:Minimally invasive surgery procedures, including stereotactic catheter aspiration and clearance of intracerebral hemorrhage (ICH) with recombinant tissue plasminogen activator hold a promise to improve outcome of supratentorial brain hemorrhage, a morbid and disabling type of stroke. A recently completed Phase III randomized trial showed improved mortality but was neutral on the primary outcome (modified Rankin scale score 0 to 3 at 1 yr). OBJECTIVE: To assess surgical performance and its impact on the extent of ICH evacuation and functional outcomes. METHODS: Univariate and multivariate models were used to assess the extent of hematoma evacuation efficacy in relation to mRS 0 to 3 outcome and postulated factors related to patient, disease, and protocol adherence in the surgical arm (n = 242) of the MISTIE trial. RESULTS: Greater ICH reduction has a higher likelihood of achieving mRS of 0 to 3 with a minimum evacuation threshold of ≤15 mL end of treatment ICH volume or ≥70% volume reduction when controlling for disease severity factors. Mortality benefit was achieved at ≤30 mL end of treatment ICH volume, or >53% volume reduction. Initial hematoma volume, history of hypertension, irregular-shaped hematoma, number of alteplase doses given, surgical protocol deviations, and catheter manipulation problems were significant factors in failing to achieve ≤15 mL goal evacuation. Greater surgeon/site experiences were associated with avoiding poor hematoma evacuation. CONCLUSION: This is the first surgical trial reporting thresholds for reduction of ICH volume correlating with improved mortality and functional outcomes. To realize the benefit of surgery, protocol objectives, surgeon education, technical enhancements, and case selection should be focused on this goal.

Neurocritical care is a distinct subspecialty focusing on the optimal management of acutely ill patients with lifethreatening neurologic and neurosurgical disease or with life-threatening neurologic manifestations of systemic disease. Care by expert healthcare providers to optimize neurologic recovery is necessary. Given the lack of an organizational framework and criteria for the development and maintenance of neurological critical care units (NCCUs), this document is put forth by the Neurocritical Care Society (NCS). Recommended organizational structure, personnel and processes necessary to develop a successful neurocritical care program are outlined. Methods: Under the direction of NCS Executive Leadership, a multidisciplinary writing group of NCS members was formed. After an iterative process, a framework was proposed and approved by members of the writing group. A draft was then written, which was reviewed by the NCS Quality Committee and NCS Guidelines Committee, members at large, and posted for public comment. Feedback was formally collated, reviewed and incorporated into the final document which was subsequently approved by the NCS Board of Directors.

A noninvasive microwave beamforming strategy is proposed for selective localized heating of biological tissue. The proposed technique is based on time multiplexing of multiple beamformers. We investigate the effectiveness of the time-multiplexed beamforming in the context of brain hyperthermia treatment by using a high-fidelity numerical head phantom of an adult female from the Virtual Family (IT'IS Foundation) as our testbed. An operating frequency of 1 GHz is considered to balance the improved treatment resolution afforded by higher frequencies against the increased penetration through the brain afforded by lower frequencies. The exact head geometry and dielectric properties of biological tissues in the head are assumed to be available for the creation of patient-specific propagation models used in beamformer design. Electromagnetic and thermal simulations based on the finite-difference time-domain method are used to evaluate the hyperthermia performance of time-multiplexed beamforming and conventional beamforming strategies. The proposed time-multiplexing technique is shown to reduce the unintended heating of healthy tissue without affecting the treatment temperature or volume. The efficacy of the method is demonstrated for target locations in three different regions of the brain. This approach has the potential to improve microwave-induced localized heating for cancer treatment via hyperthermia or heat-activated chemotherapeutic drug release.

We present a numerical study of an array-based microwave beamforming approach for non-invasive hyperthermia treatment of pediatric brain tumors. The transmit beamformer is designed to achieve localized heating-that is, to achieve constructive interference and selective absorption of the transmitted electromagnetic waves at the desired focus location in the brain while achieving destructive interference elsewhere. The design process takes into account patient-specific and target-specific propagation characteristics at 1 GHz. We evaluate the effectiveness of the beamforming approach using finite-difference time-domain simulations of two MRI-derived child head models from the Virtual Family (IT'IS Foundation). Microwave power deposition and the resulting steady-state thermal distribution are calculated for each of several randomly chosen focus locations. We also explore the robustness of the design to mismatch between the assumed and actual dielectric properties of the patient. Lastly, we demonstrate the ability of the beamformer to suppress hot spots caused by pockets of cerebrospinal fluid (CSF) in the brain. Our results show that microwave beamforming has the potential to create localized heating zones in the head models for focus locations that are not surrounded by large amounts of CSF. These promising results suggest that the technique warrants further investigation and development.

The aim of this study is to investigate the sulcal and the gyral anatomy of the orbitofrontal cortex with its arterial supply. Ten gross formaline fixed adult brains (20 hemispheres) were used to show the gyral and sulcal anatomy of the inferior frontal lobe, and its arterial supply. The arteries were investigated with special attention to the relationship between the recurrent artery of Heubner (RAH) and the gyrus rectus (GR). Medial and lateral orbital sulci were connected in 4 right hemispheres, and in 7 of the left. The orbital sulci were connected with olfactory sulcus in one right hemispheres, but not in the left. In the right hemispheres, the RAH traveled across the GR in 7 hemispheres and looped over the posterior aspect of the GR in 3 hemispheres. In the left hemispheres, RAH crossed the GR in 8 and looped over the posterior aspect of the GR before entering the anterior perforating substance in 2 hemispheres. There are considerable variations among the gyri and sulci of the orbitofrontal cortex and it is difficult to describe a precise architectural pattern. The RAH demands special attention during GR resection in aneurysm surgery.