Aneurysm wall cellularity affects healing after coil embolization: assessment in a rat saccular aneurysm model.

BACKGROUND AND PURPOSE: Despite significant technical advances, recanalization rates after endovascular therapy of ruptured intracranial aneurysms (IAs) remain a clinical challenge. A histopathological hallmark of ruptured human IA walls is mural cell loss. Mural smooth muscle cells (SMCs) are known to promote intraluminal healing in thrombosed experimental aneurysms. In this rat model we assess the natural history and healing process after coil embolization in SMC-rich and decellularized aneurysms. METHODS: Saccular aneurysms were created by end-to-side anastomosis of an arterial graft from the descending thoracic aorta of a syngeneic donor rat to the infrarenal abdominal aorta of recipient male Wistar rats. Untreated arterial grafts were immediately transplanted, whereas aneurysms with loss of mural cells were chemically decellularized before implantation. Aneurysms underwent coil implantation during aneurysm anastomosis. Animals were randomly assigned either to the non-decellularized or decellularized group and underwent macroscopic and histological analyses on days 3, 7, 21, or 90 post-coil implantation. RESULTS: A total of 55 rats underwent macroscopic and histologic analysis. After coil embolization, aneurysms with SMC-rich walls showed a linear course of thrombosis and neointima formation whereas decellularized aneurysms showed marked inflammatory wall degeneration with increased recanalization rates 21 days (p=0.002) and 90 days (p=0.037) later. The SMCs showed the ability to actively migrate into the intra-aneurysmal thrombus and participate in thrombus organization. CONCLUSIONS: Coil embolization of aneurysms with highly degenerated walls is prone to further wall degeneration, increased inflammation, and recanalization compared with aneurysms with vital SMC-rich walls.

Validation and accuracy of intraoperative CT scan using the Philips AlluraXper FD20 angiography suite for assessment of spinal instrumentation.

BACKGROUND: With the concept of the hybrid operating room gaining popularity, the authors adapted a hybrid angiographic suite with intraoperative computed tomography (iCT) to evaluate accuracy of pedicle screw placement in spinal fusion. This retrospective review examines how well iCT detected extrapedicular screw violation, to then allow repositioning and potentially avoid revision surgery. METHODS: A total of 36 consecutive patients underwent pedicle screw placement in posterior cervical, thoracic, and lumbosacral spinal fusions. All patients underwent iCT in the Philips AlluraXper FD20 angiography suite in the lumbar spine XperCT mode and postoperative conventional computed tomography (CT) scanning. Primary endpoints included the sensitivity and specificity of iCT in detecting pedicular violation characterized as minor, moderate, or severe when compared with postoperative CT. Secondary endpoint included the incidence of replaced screws during surgery and number of revision surgeries. RESULTS: Of 241 screws placed in 16 males and 20 females, iCT detected severe pedicle violation in 25 screws (10.4%); 16 screws were then repositioned during surgery. Sensitivity and specificity of iCT to detect severe screw malposition were 92.3% and 99.1%, respectively. No revision surgeries were performed in this series. CONCLUSIONS: In our series, iCT had high sensitivity and specificity in detecting severe screw malposition. As a valuable adjunct for intraoperative assessment of pedicle screw position, immediate intraoperative correction of misplaced screws then eliminated any revision surgery for our patients.

Call for uniform neuropsychological assessment after aneurysmal subarachnoid hemorrhage: Swiss recommendations.

BACKGROUND: In a high proportion of patients with favorable outcome after aneurysmal subarachnoid hemorrhage (aSAH), neuropsychological deficits, depression, anxiety, and fatigue are responsible for the inability to return to their regular premorbid life and pursue their professional careers. These problems often remain unrecognized, as no recommendations concerning a standardized comprehensive assessment have yet found entry into clinical routines. METHODS: To establish a nationwide standard concerning a comprehensive assessment after aSAH, representatives of all neuropsychological and neurosurgical departments of those eight Swiss centers treating acute aSAH have agreed on a common protocol. In addition, a battery of questionnaires and neuropsychological tests was selected, optimally suited to the deficits found most prevalent in aSAH patients that was available in different languages and standardized. RESULTS: We propose a baseline inpatient neuropsychological screening using the Montreal Cognitive Assessment (MoCA) between days 14 and 28 after aSAH. In an outpatient setting at 3 and 12 months after bleeding, we recommend a neuropsychological examination, testing all relevant domains including attention, speed of information processing, executive functions, verbal and visual learning/memory, language, visuo-perceptual abilities, and premorbid intelligence. In addition, a detailed assessment capturing anxiety, depression, fatigue, symptoms of frontal lobe affection, and quality of life should be performed. CONCLUSIONS: This standardized neuropsychological assessment will lead to a more comprehensive assessment of the patient, facilitate the detection and subsequent treatment of previously unrecognized but relevant impairments, and help to determine the incidence, characteristics, modifiable risk factors, and the clinical course of these impairments after aSAH.