Medical management and surgery versus medical management alone for symptomatic cerebral cavernous malformation (CARE): a feasibility study and randomised, open, pragmatic, pilot phase trial

BACKGROUND

The highest priority uncertainty for people with symptomatic cerebral cavernous malformation is whether to have medical management and surgery or medical management alone. We conducted a pilot phase randomised controlled trial to assess the feasibility of addressing this uncertainty in a definitive trial.

METHODS

The CARE pilot trial was a prospective, randomised, open-label, assessor-blinded, parallel-group trial at neuroscience centres in the UK and Ireland. We aimed to recruit 60 people of any age, sex, and ethnicity who had mental capacity, were resident in the UK or Ireland, and had a symptomatic cerebral cavernous malformation. Computerised, web-based randomisation assigned participants (1:1) to medical management and surgery (neurosurgical resection or stereotactic radiosurgery) or medical management alone, stratified by the neurosurgeon's and participant's consensus about the intended type of surgery before randomisation. Assignment was open to investigators, participants, and carers, but not clinical outcome event adjudicators. Feasibility outcomes included site engagement, recruitment, choice of surgical management, retention, adherence, data quality, clinical outcome event rate, and protocol implementation. The primary clinical outcome was symptomatic intracranial haemorrhage or new persistent or progressive non-haemorrhagic focal neurological deficit due to cerebral cavernous malformation or surgery during at least 6 months of follow-up. We analysed data from all randomly assigned participants according to assigned management. This trial is registered with ISRCTN (ISRCTN41647111) and has been completed.

FINDINGS

Between Sept 27, 2021, and April 28, 2023, 28 (70%) of 40 sites took part, at which investigators screened 511 patients, of whom 322 (63%) were eligible, 202 were approached for recruitment, and 96 had collective uncertainty with their neurosurgeon about whether to have surgery for a symptomatic cerebral cavernous malformation. 72 (22%) of 322 eligible patients were randomly assigned (mean recruitment rate 0·2 [SD 0·25] participants per site per month) at a median of 287 (IQR 67-591) days since the most recent symptomatic presentation. Participants' median age was 50·6 (IQR 38·6-59·2) years, 68 (94%) of 72 participants were adults, 41 (57%) were female, 66 (92%) were White, 56 (78%) had a previous intracranial haemorrhage, and 28 (39%) had a previous epileptic seizure. The intended type of surgery before randomisation was neurosurgical resection for 19 (26%) of 72, stereotactic radiosurgery for 44 (61%), and no preference for nine (13%). Baseline clinical and imaging data were complete for all participants. 36 participants were randomly assigned to medical management and surgery (12 to neurosurgical resection and 24 to stereotactic radiosurgery) and 36 to medical management alone. Three (4%) of 72 participants withdrew, one was lost to follow-up, and one declined face-to-face follow-up, leaving 67 (93%) retained at 6-months' clinical follow-up. 61 (91%) of 67 participants with follow-up adhered to the assigned management strategy. The primary clinical outcome occurred in two (6%) of 33 participants randomly assigned to medical management and surgery (8·0%, 95% CI 2·0-32·1 per year) and in two (6%) of 34 participants randomly assigned to medical management alone (7·5%, 1·9-30·1 per year). Investigators reported no deaths, no serious adverse events, one protocol violation, and 61 protocol deviations.

INTERPRETATION

This pilot phase trial exceeded its recruitment target, but a definitive trial will require extensive international engagement.

FUNDING

National Institute for Health and Care Research.

A pilot clinical study to estimate intracranial pressure utilising cerebral photoplethysmograms in traumatic brain injury patients

PURPOSE

In this research, a non-invasive intracranial pressure (nICP) optical sensor was developed and evaluated in a clinical pilot study. The technology relied on infrared light to probe brain tissue, using photodetectors to capture backscattered light modulated by vascular pulsations within the brain's vascular tissue. The underlying hypothesis was that changes in extramural arterial pressure could affect the morphology of recorded optical signals (photoplethysmograms, or PPGs), and analysing these signals with a custom algorithm could enable the non-invasive calculation of intracranial pressure (nICP).

METHODS

This pilot study was the first to evaluate the nICP probe alongside invasive ICP monitoring as a gold standard. nICP monitoring occurred in 40 patients undergoing invasive ICP monitoring, with data randomly split for machine learning. Quality PPG signals were extracted and analysed for time-based features. The study employed Bland-Altman analysis and ROC curve calculations to assess nICP accuracy compared to invasive ICP data.

RESULTS

Successful acquisition of cerebral PPG signals from traumatic brain injury (TBI) patients allowed for the development of a bagging tree model to estimate nICP non-invasively. The nICP estimation exhibited 95% limits of agreement of 3.8 mmHg with minimal bias and a correlation of 0.8254 with invasive ICP monitoring. ROC curve analysis showed strong diagnostic capability with 80% sensitivity and 89% specificity.

CONCLUSION

The clinical evaluation of this innovative optical nICP sensor revealed its ability to estimate ICP non-invasively with acceptable and clinically useful accuracy. This breakthrough opens the door to further technological refinement and larger-scale clinical studies in the future.

TRIAL REGISTRATION

NCT05632302, 11th November 2022, retrospectively registered.

Feasibility of comparing medical management and surgery (with neurosurgery or stereotactic radiosurgery) with medical management alone in people with symptomatic brain cavernoma - protocol for the Cavernomas: A Randomised Effectiveness (CARE) pilot trial

INTRODUCTION

The top research priority for cavernoma, identified by a James Lind Alliance Priority setting partnership was 'Does treatment (with neurosurgery or stereotactic radiosurgery) or no treatment improve outcome for people diagnosed with a cavernoma?' This pilot randomised controlled trial (RCT) aims to determine the feasibility of answering this question in a main phase RCT.

METHODS AND ANALYSIS

We will perform a pilot phase, parallel group, pragmatic RCT involving approximately 60 children or adults with mental capacity, resident in the UK or Ireland, with an unresected symptomatic brain cavernoma. Participants will be randomised by web-based randomisation 1:1 to treatment with medical management and with surgery (neurosurgery or stereotactic radiosurgery) versus medical management alone, stratified by prerandomisation preference for type of surgery. In addition to 13 feasibility outcomes, the primary clinical outcome is symptomatic intracranial haemorrhage or new persistent/progressive focal neurological deficit measured at 6 monthly intervals. An integrated QuinteT Recruitment Intervention (QRI) evaluates screening logs, audio recordings of recruitment discussions, and interviews with recruiters and patients/parents/carers to identify and address barriers to participation. A Patient Advisory Group has codesigned the study and will oversee its progress.

ETHICS AND DISSEMINATION

This study was approved by the Yorkshire and The Humber-Leeds East Research Ethics Committee (21/YH/0046). We will submit manuscripts to peer-reviewed journals, describing the findings of the QRI and the Cavernomas: A Randomised Evaluation (CARE) pilot trial. We will present at national specialty meetings. We will disseminate a plain English summary of the findings of the CARE pilot trial to participants and public audiences with input from, and acknowledgement of, the Patient Advisory Group.

TRIAL REGISTRATION NUMBER

ISRCTN41647111.

Decompressive Craniectomy versus Craniotomy for Acute Subdural Hematoma

BACKGROUND

Traumatic acute subdural hematomas frequently warrant surgical evacuation by means of a craniotomy (bone flap replaced) or decompressive craniectomy (bone flap not replaced). Craniectomy may prevent intracranial hypertension, but whether it is associated with better outcomes is unclear.

METHODS

We conducted a trial in which patients undergoing surgery for traumatic acute subdural hematoma were randomly assigned to undergo craniotomy or decompressive craniectomy. An inclusion criterion was a bone flap with an anteroposterior diameter of 11 cm or more. The primary outcome was the rating on the Extended Glasgow Outcome Scale (GOSE) (an 8-point scale, ranging from death to "upper good recovery" [no injury-related problems]) at 12 months. Secondary outcomes included the GOSE rating at 6 months and quality of life as assessed by the EuroQol Group 5-Dimension 5-Level questionnaire (EQ-5D-5L).

RESULTS

A total of 228 patients were assigned to the craniotomy group and 222 to the decompressive craniectomy group. The median diameter of the bone flap was 13 cm (interquartile range, 12 to 14) in both groups. The common odds ratio for the differences across GOSE ratings at 12 months was 0.85 (95% confidence interval, 0.60 to 1.18; P = 0.32). Results were similar at 6 months. At 12 months, death had occurred in 30.2% of the patients in the craniotomy group and in 32.2% of those in the craniectomy group; a vegetative state occurred in 2.3% and 2.8%, respectively, and a lower or upper good recovery occurred in 25.6% and 19.9%. EQ-5D-5L scores were similar in the two groups at 12 months. Additional cranial surgery within 2 weeks after randomization was performed in 14.6% of the craniotomy group and in 6.9% of the craniectomy group. Wound complications occurred in 3.9% of the craniotomy group and in 12.2% of the craniectomy group.

CONCLUSIONS

Among patients with traumatic acute subdural hematoma who underwent craniotomy or decompressive craniectomy, disability and quality-of-life outcomes were similar with the two approaches. Additional surgery was performed in a higher proportion of the craniotomy group, but more wound complications occurred in the craniectomy group. (Funded by the National Institute for Health and Care Research; RESCUE-ASDH ISRCTN Registry number, ISRCTN87370545.).

Risk of Aneurysm Rupture (ROAR) study: protocol for a long-term, longitudinal, UK multicentre study of unruptured intracranial aneurysms

INTRODUCTION

Unruptured intracranial aneurysms (UIA) are common in the adult population, but only a relatively small proportion will rupture. It is therefore essential to have accurate estimates of rupture risk to target treatment towards those who stand to benefit and avoid exposing patients to the risks of unnecessary treatment. The best available UIA natural history data are the PHASES study. However, this has never been validated and given the known heterogeneity in the populations, methods and biases of the constituent studies, there is a need to do so. There are also many potential predictors not considered in PHASES that require evaluation, and the estimated rupture risk is largely based on short-term follow-up (mostly 1 year). The aims of this study are to: (1) test the accuracy of PHASES in a UK population, (2) evaluate additional predictors of rupture and (3) assess long-term UIA rupture rates.

METHODS AND ANALYSIS

The Risk of Aneurysm Rupture study is a longitudinal multicentre study that will identify patients with known UIA seen in neurosurgery units. Patients will have baseline demographics and aneurysm characteristics collected by their neurosurgery unit and then a single aggregated national cohort will be linked to databases of hospital admissions and deaths to identify all patients who may have subsequently suffered a subarachnoid haemorrhage. All matched admissions and deaths will be checked against medical records to confirm the diagnosis of aneurysmal subarachnoid haemorrhage. The target sample size is 20 000 patients. The primary outcome will be aneurysm rupture resulting in hospital admission or death. Cox regression models will be built to test each of the study's aims.

ETHICS AND DISSEMINATION

Ethical approval has been given by South Central Hampshire A Research Ethics Committee (21SC0064) and Confidentiality Advisory Group support (21CAG0033) provided under Section 251 of the NHS Act 2006. The results will be disseminated in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN17658526.

Vagus nerve stimulation paired with rehabilitation for stroke: Implantation experience from the VNS-REHAB trial

OBJECTIVE

Vagus Nerve Stimulation (VNS) paired with rehabilitation delivered by the Vivistim® Paired VNS™ System was approved by the FDA in 2021 to improve motor deficits in chronic ischemic stroke survivors with moderate to severe arm and hand impairment. Vagus nerve stimulators have previously been implanted in over 125,000 patients for treatment-resistant epilepsy and the surgical procedure is generally well-tolerated and safe. In this report, we describe the Vivistim implantation procedure, perioperative management, and complications for chronic stroke survivors enrolled in the pivotal trial.

METHODS

The pivotal, multisite, randomized, triple-blind, sham-controlled trial (VNS-REHAB) enrolled 108 participants. All participants were implanted with the VNS device in an outpatient procedure. Thrombolytic agents were temporarily discontinued during the perioperative period. Participants were discharged within 48 hrs and started rehabilitation therapy approximately 10 days after the Procedure.

RESULTS

The rate of surgery-related adverse events was lower than previously reported for VNS implantation for epilepsy and depression. One participant had vocal cord paresis that eventually resolved. There were no serious adverse events related to device stimulation. Over 90% of participants were taking antiplatelet drugs (APD) or anticoagulants and no adverse events or serious adverse events were reported as a result of withholding these medications during the perioperative period.

CONCLUSIONS

This study is the largest, randomized, controlled trial in which a VNS device was implanted in chronic stroke survivors. Results support the use of the Vivistim System in chronic stroke survivors, with a safety profile similar to VNS implantations for epilepsy and depression.

Prognosticating outcome using magnetic resonance imaging in patients with moderate to severe traumatic brain injury: a machine learning approach

INTRODUCTION

Over the last decade advancements in computer processing have enabled the application of machine learning (ML) to complex medical problems. Convolutional neural networks (CNN), a type of ML, have been used to interrogate medical images for variety of purposes. In this study, we aimed to investigate the potential application of CNN in prognosticating patients with traumatic brain injury (TBI).

METHODS

Patients with moderate to severe TBI and evidence of diffuse axonal injury (DAI) were selected retrospectively. A CNN model was developed using a training subgroup and a holdout subgroup was used as a testing dataset. We reported the model characteristics including area under the receiver operating characteristic curve (AUC).

RESULTS

We included a total of 38 patient, of which we generated 725 MRI sections. We developed a CNN model based on a modified AlexNet architecture that interpreted the brain stem injury to generate outcome predictions. The model was able to predict GOS outcomes with a specificity of 0.43 and a sensitivity of 0.997. It showed an AUC of 0.917.

CONCLUSION

The utilization of machine learning MRI analysis for prognosticating patients with TBI is a valued method that require further investigation. This will require multicentre collaboration to generate large datasets.

Applying Convolutional Neural Networks to Neuroimaging Classification Tasks: A Practical Guide in Python

In this chapter, we describe the process of obtaining medical imaging data and its storage protocol. The authors also explain in a step-by-step approach how to extract and prepare the medical imaging data for machine learning algorithms. And finally, the process of building and assessing a convolutional neural network for medical imaging data is illustrated.

435 THE IMPACT OF COMPREHENSIVE GERIATRIC ASSESSMENT IN THE OUTCOMES OF OLDER ACUTE NEUROSURGICAL PATIENTS

Introduction

As the population ages, an increasing proportion of the neurosurgical caseload is comprised of older patients. This trend is reinforced by technical advances and anaesthetic considerations within the field, allowing a higher proportion of patients eligible for surgery. Comprehensive geriatric assessment (CGA) is the gold standard clinical approach for evaluating older patients. Peri-operative care of older people (POPS) has provided strong evidence that CGA services can result in fewer post-operative complications. However, this evidence stems largely from trauma and orthopaedic surgery. Currently, there is little evidence of the impact CGA has on older neurosurgical patients. The study aimed to investigate whether CGA for older neurosurgical patients improved outcomes such as thirty-day mortality and length of stay.

Methods

A control group was established by collecting retrospective data for all acute neurosurgical patients over the age of 65. This was then compared with an intervention group who received CGA in the form of regular geriatric consultant reviews. 49 patients were recruited into each group.

Results

Analysis showed that the interventional group had a significantly higher mean age and level of frailty. They also had more confirmed complications with a significant difference in the diagnosis of pneumonia (p = 0.05) and hyponatremia (p = 0.015). Despite this, the thirty-day mortality was lower and average length of stay was on average two days shorter compared to the control group, although this did not reach statistical significance (p = 0.701). The study showed that more patients who received a CGA were discharged home (p = 0.209).

Conclusion

Our findings suggest that CGA input for older neurosurgical patients improves outcomes and should be incorporated routinely into neurosurgical clinical pathways.

Clinical Application of Shear Wave Elastography for Assisting Brain Tumor Resection

Background

The clinical outcomes for brain tumor resection have been shown to be significantly improved with increased extent of resection. To achieve this, neurosurgeons employ different intra-operative tools to improve the extent of resection of brain tumors, including ultrasound, CT, and MRI. Young’s modulus (YM) of brain tumors have been shown to be different from normal brain but the accuracy of SWE in assisting brain tumor resection has not been reported.

Aims

To determine the accuracy of SWE in detecting brain tumor residual using post-operative MRI scan as “gold standard”.

Methods

Thirty-four patients (aged 1–62 years, M:F = 15:20) with brain tumors were recruited into the study. The intraoperative SWE scans were performed using Aixplorer^® (SuperSonic Imagine, France) using a sector transducer (SE12-3) and a linear transducer (SL15-4) with a bandwidth of 3 to 12 MHz and 4 to 15 MHz, respectively, using the SWE mode. The scans were performed prior, during and after brain tumor resection. The presence of residual tumor was determined by the surgeon, ultrasound (US) B-mode and SWE. This was compared with the presence of residual tumor on post-operative MRI scan.

Results

The YM of the brain tumors correlated significantly with surgeons’ findings (ρ = 0.845, p < 0.001). The sensitivities of residual tumor detection by the surgeon, US B-mode and SWE were 36%, 73%, and 94%, respectively, while their specificities were 100%, 63%, and 77%, respectively. There was no significant difference between detection of residual tumor by SWE, US B-mode, and MRI. SWE and MRI were significantly better than the surgeon’s detection of residual tumor (p = 0.001 and p < 0.001, respectively).

Conclusions

SWE had a higher sensitivity in detecting residual tumor than the surgeons (94% vs. 36%). However, the surgeons had a higher specificity than SWE (100% vs. 77%). Therefore, using SWE in combination with surgeon’s opinion may optimize the detection of residual tumor, and hence improve the extent of brain tumor resection.

The Silk Vista Baby: Initial experience and report of two cases

In this report, we present two cases using a novel flow diverter, the Silk Vista Baby, to treat aneurysms successfully, both ruptured and unruptured, that would have been difficult to treat using alternative flow diverters. We describe the clinical and radiological features, outcome and the unique features of the Silk Vista Baby flow diverter.

P14 Management of traumatic skull base fractures and their complications – a seven-year experience

Objectives

We aim to present our experience of managing traumatic base of skull fractures and our outcomes.

Design

Retrospective case note review.

Subjects

All patients in our trauma database with radiographic evidence of a skull base fracture from January 2010 to June 2017.

Methods

Skull base fractures were classified according to their anatomical location. Evidence of vascular injury, CSF leak or cranial nerve injury were recorded. The mechanism of injury, length of follow up, interventions and outcomes were documented.

Results

872 cases had a skull base fracture diagnosed by head CT scan, of which 760 had sufficient radiological and clinic data to analyse. 79.4% of the cohort were male, with a mean age of 43 years. Median length of stay was 8 days and median length of follow up was 114 days. 40.1% were lost to follow up. The mortality rate was 14.9%. Injuries predominantly affected the middle cranial fossa. Vascular injury was the commonest complication (n=87), followed by CSF leak (n=38). 28 patients sustained injury to the facial nerve. Complications were managed conservatively in most cases.

Conclusions

There is little reported literature on the long term outcomes of patients who sustain CSF leak, vascular injury or cranial nerve deficit following a base of skull fracture. In our experience, many of these patients are lost to follow up and indeed, the nature of this study is limited by it’s retrospective nature. Further prospective work must be done in this patient group to better understand the history of these patients.

TP1-7 Extended glasgow outcome scale – when would you rather die?

Objectives

Extended Glasgow Outcome Scale is the primary outcome measure in trials involving neurotrauma patients. Conventional dichotomization characterises unfavourable outcomes as upper severe disability or worse, however RESCUE-ICP changed this to consider upper severe disability as a favourable outcome. As the recent consensus meeting in Cambridge proved, opinion of what constitutes acceptable recovery can vary widely between individuals.

Design

To survey patients with brain injury and compare them to the opinions of staff routinely involved in the care of such patients.

Subjects

Patients with brain injuries, neurosurgery staff and ITU staff.

Method

GOS-E sheets were given to neurotrauma patients and asked to circle the outcome they considered unfavourable and therefore would rather not survive. This was compared to the same question posed to neurosurgery staff members, and ITU staff members.

Results

67 responses collected (20 patients, 27 neurosurgery staff, 20 ITU staff). Mean GOS-E score deemed unfavourable and therefore not worth survival was 3.6, mode 3 (Patient mean 3.15, mode 3. Neurosurgery mean 3.63, mode 4. ITU mean 4.0, mode 5. p>0.05).

Conclusion

What constitutes unfavourable outcome varies between each group of people questioned. Patients who have experienced brain injuries were more likely to feel that upper severe disability was an acceptable outcome when compared to the staff that care for them. It is imperative we take this in to consideration when recommending treatment strategies in an acute setting.

Further characterization of changes in axial strain elastograms due to the presence of slippery tumor boundaries

Elastography measures tissue strain, which can be interpreted under certain simplifying assumptions to be representative of the underlying stiffness distribution. This is useful in cancer diagnosis where tumors tend to have a different stiffness to healthy tissue and has also shown potential to provide indication of the degree of bonding at tumor-tissue boundaries, which is clinically useful because of its dependence on tumor pathology. We consider the changes in axial strain for the case of a symmetrical model undergoing uniaxial compression, studied by characterizing changes in tumor contrast transfer efficiency (CTE), inclusion to background strain contrast and strain contrast generated by slip motion, as a function of Young's modulus contrast and applied strain. We present results from a finite element simulation and an evaluation of these results using tissue-mimicking phantoms. The simulation results show that a discontinuity in displacement data at the tumor boundary, caused by the surrounding tissue slipping past the tumor, creates a halo of "pseudostrain" across the tumor boundary. Mobile tumors also appear stiffer on elastograms than adhered tumors, to the extent that tumors that have the same Young's modulus as the background may in fact be visible as low-strain regions, or those that are softer than the background may appear to be stiffer than the background. Tumor mobility also causes characteristic strain heterogeneity within the tumor, which exhibits low strain close to the slippery boundary and increasing strain toward the center of the tumor. These results were reproduced in phantom experiments. In addition, phantom experiments demonstrated that when fluid lubrication is present at the boundary, these effects become applied strain-dependent as well as modulus-dependent, in a systematic and characteristic manner. The knowledge generated by this study is expected to aid interpretation of clinical strain elastograms by helping to avoid misinterpretation as well as provide additional diagnostic criteria stated in the paper and stimulate further research into the application of elastography to tumor mobility assessment.

Spinal epidural hematoma caused by pseudogout: a case report and literature review

Study Design Case report. Objective We present the first reported case of spontaneous spinal epidural hematoma secondary to calcium pyrophosphate crystal deposition disease (pseudogout) in a 75-year-old woman. Methods A retrospective review of the patient's case notes was undertaken and the limited literature on this subject reviewed. Results This patient presented with sudden-onset lower limb paresis, sensory loss, urinary retention, and back pain. Magnetic resonance imaging showed an epidural hematoma, which was evacuated. Histologic specimens of the clot showed calcium pyrophosphate dihydrate crystal deposits (pseudogout). Conclusion The importance of histopathologic review of surgical specimens is highlighted when considering the differential diagnosis of apparently spontaneous spinal epidural hematoma.

A novel technique of detecting MRI-negative lesion in focal symptomatic epilepsy: intraoperative ShearWave elastography

Focal symptomatic epilepsy is the most common form of epilepsy that can often be cured with surgery. A small proportion of patients with focal symptomatic epilepsy do not have identifiable lesions on magnetic resonance imaging (MRI). The most common pathology in this group is type II focal cortical dysplasia (FCD), which is a subtype of malformative brain lesion associated with medication-resistant epilepsy. We present a patient with MRI-negative focal symptomatic epilepsy who underwent invasive electrode recordings. At the time of surgery, a novel ultrasound-based technique called ShearWave Elastography (SWE) was performed. A 0.5 cc lesion was demonstrated on SWE but was absent on B-mode ultrasound and 3-T MRI. Electroencephalography (EEG), positron emission tomography (PET), and magnetoencephalography (MEG) scans demonstrated an abnormality in the right frontal region. On the basis of this finding, a depth electrode was implanted into the lesion. Surgical resection and histology confirmed the lesion to be type IIb FCD. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

Diagnostic implications of histological analysis of neurosurgical aspirate in addition to routine resections

Many neurosurgical centers use surgical aspirators to remove brain tumor tissue. The resulting aspirate consists of fragmented viable tumor, normal or tumor-infiltrated brain tissue as well as necrotic tissue, depending on the type of tumor. Typically, such fragmented aspirate material is collected but discarded and not included when making the histopathological diagnosis. Whereas the general suitability of surgical aspirate for histological diagnosis and immunohistochemical staining has been reported previously, we have systematically investigated whether the collection and histological examination of surgical aspirate has an impact on diagnosis, in particular on the tumor grading, by providing additional features. Surgical and aspirate specimens from 85 consecutive neurosurgical procedures were collected and routinely processed. Sixty-five of the 85 specimens were intrinsic brain tumors and the remainder consisted of metastatic tumors, meningiomas, schwannomas and lymphomas. Important diagnostic features seen in surgical aspirate were microvascular proliferation (n = 3), more representative necrosis (n = 2), and gemistocytic component (n = 2). In one case, microvasular proliferations were seen in the aspirate only, leading to a change of diagnosis. Collection of surgical aspirate also generates additional archival material which can be microdissected and used for tissue microarrays or for molecular studies.

A new method for the acquisition of ultrasonic strain image volumes

This article presents a new method for acquiring three-dimensional (3-D) volumes of ultrasonic axial strain data. The method uses a mechanically-swept probe to sweep out a single volume while applying a continuously varying axial compression. Acquisition of a volume takes 15-20 s. A strain volume is then calculated by comparing frame pairs throughout the sequence. The method uses strain quality estimates to automatically pick out high quality frame pairs, and so does not require careful control of the axial compression. In a series of in vitro and in vivo experiments, we quantify the image quality of the new method and also assess its ease of use. Results are compared with those for the current best alternative, which calculates strain between two complete volumes. The volume pair approach can produce high quality data, but skillful scanning is required to acquire two volumes with appropriate relative strain. In the new method, the automatic quality-weighted selection of image pairs overcomes this difficulty and the method produces superior quality images with a relatively relaxed scanning technique.

Sir Victor Horsley's 19th century operations at the National Hospital for Neurology and Neurosurgery, Queen Square

Although he was not the first man to operate on the brain, Sir Victor Horsley was the world's first surgeon appointed to a hospital post to perform brain surgery, which happened in 1886 at the National Hospital for Neurology and Neurosurgery, Queen Square, London. The authors examined the patient records between 1886 and 1899 and found 151 operations performed by Sir Victor Horsley at the National Hospital, including craniotomies, laminectomies, and nerve divisions. The authors present the outcome data and case illustrations of cerebral tumor resections and laminectomies from the nineteenth century. Outcomes and notable pioneering achievements are highlighted.

Retrograde intraventricular hemorrhage caused by a traumatic sacral pseudomeningocele in the presence of spina bifida occulta. Case report

The authors present the case of a large, posttraumatic sacral pseudomeningocele in the presence of spina bifida occulta. A pseudomeningocele in the sacral region is associated with trauma and with Marfan syndrome, but only one occurrence has been reported in association with spinal dysraphism. Trauma resulted in bleeding into the pseudomeningocele and retrograde passage of blood and fat into the ventricles. An oculomotor nerve palsy subsequently developed in the patient. The authors suspected a subarachnoid hemorrhage caused by a posterior communicating artery aneurysm, although this hypothesis was refuted on further investigation. The pseudomeningocele was drained by direct exposure of the neck and opening of the sac. Postoperatively, communicating hydrocephalus developed and the patient underwent ventriculoperitoneal shunt placement, resulting in resolution of the cranial nerve palsies. This first report of intradural bleeding from direct trauma to a pseudomeningocele illustrates the rare phenomenon of retrograde passage of blood from the sacral region to the brain. It also illustrates a possible but unlikely differential diagnosis of intraventricular blood and fat.

Suppression of macrophage function by suture materials and anastomotic recurrence of Crohn's disease

After surgical excision of bowel, Crohn's disease is likely to recur around the anastomosis. It is suggested that this may indicate a biological effect of suture materials on gastrointestinal immunology. To investigate this, the influence of six suture materials on the function of macrophages obtained from the rat peritoneal cavity and human intestinal mucosa was assessed. All materials significantly impaired macrophage function.

Experimental carcinogenesis at sutured and sutureless colonic anastomoses

This study explores the role of sutures and the healing colonic wound in experimental carcinogenesis. One hundred sixty rats underwent surgery with colotomy and repair using silk, steel, or Vicryl (Ethicon, Somerville, NJ) sutures or a sutureless technique. Forty rats had a sham procedure. All animals received azoxymethane for 12 weeks at a dose of 10 mg/kg/week. Half the rats commenced carcinogen before surgery, and half commenced it eight weeks after surgery. Animals with anastomotic tumors were found in 46 percent of the sham group (P less than 0.05 cf. sutured), 41 percent of the sutureless group (P less than 0.02 cf. sutured), and 68 percent of the sutured group. The corresponding figures for anastomotic carcinoma were 9 percent (P less than 0.001 cf. sutured), 22 percent, and 38 percent. No significant differences in tumor yield were noted among the different sutures. However, several differences were noted between the two carcinogen models. In those animals that received surgery first, there was a higher incidence of anastomotic tumors (P less than 0.002) and cancers (P less than 0.0001) in the sutured and sutureless groups, and those tumors that occurred in the sutured group were considerably larger than in those that had carcinogen first (15.9 mm cf. 4.9 mm; P less than 0.0001). Overall, all sutures seem to enhance anastomotic tumor formation, and we would suggest that a sutureless anastomosis may diminish this risk.