Scott R. Shepard

Biophysical measurement of brain tumor cohesion

An advantage of using 3D multicellular spheres to study tumor biology is that they better approximate the interactions encountered by cells in vivo. Our previous studies have shown that the process of spheroid formation is governed by the same thermodynamic principles driving the formation of liquid droplets. This liquid‐like behavior enables us to measure a key property influencing tumor behavior, namely, intercellular cohesion. We have developed a method, tissue surface tensiometry (TST), to measure the cohesivity, expressible as surface tension (σ), of tissue aggregates under physiologic conditions. This study utilizes TST to measure the cohesivity of 3 widely used malignant astrocytoma cell lines of different in vitro invasive potentials. We compare invasiveness with aggregate cohesivity and with the expression of N‐cadherin, a key mediator of cell‐cell cohesion in neural tissues. We show that the cell lines exhibit liquid‐like behavior since they form spheroids whose surface tension is both force‐ and volume‐independent; that aggregates from each cell line have a distinct surface tension that correlates with their in vitro invasive capacity; that dexamethasone (Dex), a widely used therapeutic agent for the treatment of tumor‐related cerebral edema, increases aggregate cohesivity and decreases invasiveness; that dexamethasone treatment decreases invasion in a dose‐dependent manner but only when cells are in direct contact with one another; and that dex‐mediated decreased invasiveness correlates with increased aggregate cohesivity as measured by TST but not with N‐cadherin expression or function. Our results demonstrate that for these cell lines, cohesivity is an excellent predictor of in vitro invasiveness.

Surgery of brain metastases - Is there still a place for it?

SummaryThe role of surgery in the treatment of metastatic brain tumors has always been a source of controversy. It was only in the early 1990s that two randomized prospective trials demonstrated that surgery plus radiation therapy improved survival in patients with single metastatic brain tumors vs. radiation therapy alone. This paper reviews these articles as well as other evidence outlining management options for multiple brain metastases. An attempt has been made to better define the role of surgery in brain metastases. The prognostic factors for brain metastases after surgery are also reviewed and the data comparing stereotactic radiosurgery to surgery is examined. A short description of surgical planning, operative techniques and tools, followed by a discussion on complication avoidance before, during, and after surgery is included.

Traumatic pseudoaneurysm of the basilar artery.

From JFK Medical Center, JFK Johnson Rehabilitation Institute, UMDNJ-RWJ Medical School, Department of PM&R, Edison, New Jersey (KMM, RM); JFK Medical Center, Edison Radiology Group, Edison New Jersey (WBF); Robert Wood Johnson University Hospital, University Radiology Group, East Brunswick, New Jersey (IK, SR); and Department of Surgery, Section of Neurosurgery, Robert Wood Johnson School of Medicine (SS).

Use of anti-platelet agents after traumatic intracranial hemorrhage

OBJECTIVE To evaluate the risk of hemorrhagic complications associated with starting anti-platelet therapy (APT) after acute traumatic intracranial hemorrhage (tICH) and to examine the frequency of thrombotic complications. PATIENTS AND METHODS We retrospectively identified all patients admitted to our institution with tICH that received APT during their initial hospitalization over a three-year period. We reviewed their demographics, hospital course, clinical indication and timing for initiation of APT, and complications. RESULTS A total of 222 patients were identified. The median age and Injury Severity Score (ISS) was 61 and 21, respectively. Fifty (23%) patients required neurosurgical procedures. APTs were initiated due to a history of APT use in 91 patients (41%) and blunt cerebrovascular injury in 86 patients (38.6%). The median time from injury to starting APT was 4 days. Immediate complications including new or worsening hemorrhage occurred in 1 (<1%) patient. Delayed hemorrhagic complications occurred in 6 (4.7%) patients. Thrombotic events occurred in 21 (9.4%) patients prior to starting APT. Thirteen (5.8%) of these were potentially preventable. CONCLUSION The risk of immediate and delayed intracranial hemorrhages from initiating APT after tICH must be weighed against the morbidity of delaying indicated thrombotic prophylaxis. Our initial data indicates that hemorrhagic complications are infrequent, and thrombotic complications can have significant clinical consequences. Our retrospective review provides the first rates of complications for this patient population.

Evaluation and Management of Traumatic Brain Injury

A 22-year-old man is brought to the emergency room following a highspeed motorcycle accident. The paramedics report that the patient struck a tree and that there was a 5-minute loss of consciousness. On arrival, the patient has the following vital signs: respiratory rate, 12; blood pressure, 150/75; heart rate, 92. He opens his eyes to painful stimuli, follows simple commands, and answers questions with inappropriate words.