Currently, magnetic resonance imaging(MRI) is the only imaging modality available which is capable of acquiring intra-operative images frequently with acceptable spatial and contrast resolution. However, the incorpora...Currently, magnetic resonance imaging(MRI) is the only imaging modality available which is capable of acquiring intra-operative images frequently with acceptable spatial and contrast resolution. However, the incorporation of MRI technology into the operating room requires special anesthetic considerations. It may include various aspects such as transport, remote location anesthesia, strong electromagnetic field, use of approved items, equipment counts, possible emergencies, and surgery in awake patients. The patient safety may be compromised by health-related, equipment-related, and procedure-related risks. Direct patient observation may be compromised by acoustic noise, darkened environment, obstructed line of sight, and distractions along with difficult access to the patient for airway management. Most often, the patient's head will be 180° away from the anesthesiologist during the procedure. Several monitors exist that are designed for conditional use in a MR environment. The general design criterion in these monitors is to eliminate conductors that carry electrical signals for monitoring physiologic parameters of the patient. General anesthesia requires an extended anesthetic circuit for ventilation maintenance and drug administration because the patient is located farther from the anesthesia machine than in traditional operating room settings. Dead space creates a time delay before the volatile anesthetic and drugs are administered and when expected effects can be observed. Therefore, the attending anaesthesiologists must understand the above aspects for safe conduct of neurosurgical procedures by minimizing MRI associated accidents while assuring optimal patient vigilance.展开更多
The goal in brain tumor surgery is to remove the maxi-mum achievable amount of the tumor, preventing damage to "eloquent" brain regions as the amount of brain tumor resection is one of the prognostic factors...The goal in brain tumor surgery is to remove the maxi-mum achievable amount of the tumor, preventing damage to "eloquent" brain regions as the amount of brain tumor resection is one of the prognostic factors for time to tumor progression and median survival. To achieve this goal, a variety of technical advances have been in-troduced, including an operating microscope in the late 1950 s, computer-assisted devices for surgical navigation and more recently, intraoperative imaging to incorporate and correct for brain shift during the resection of the lesion. However, surgically induced contrast enhancement along the rim of the resection cavity hampers interpretation of these intraoperatively acquired magnetic resonance images. To overcome this uncertainty, perfusion techniques [dynamic contrast enhanced magnetic resonance imaging(DCE-MRI), dynamic susceptibility contrast magnetic resonance imaging(DSC-MRI)] have been introduced that can differentiate residual tumor from surgically induced changes at the rim of the resec-tion cavity and thus overcome this remaining uncer-tainty of intraoperative MRI in high grade brain tumor resection.展开更多
Background Intraoperative ultrasound (IOUS) has been procedures. In this study, we aimed to evaluate the potential the resection of small, deep-seated, or ill-defined lesions. ncreasingly used as a guiding tool duri...Background Intraoperative ultrasound (IOUS) has been procedures. In this study, we aimed to evaluate the potential the resection of small, deep-seated, or ill-defined lesions. ncreasingly used as a guiding tool during neurosurgical application of intraoperative ultrasound assisted surgery in Methods Eighty-six consecutive patients with small, deep-seated, or ill-defined intracerebral lesions were studied prospectively. An improved intraoperative imaging technique and surgical setup were practiced during the surgery. IOUS was performed in three orthogonal imaging planes (horizontal, coronal and sagittal). Results Histopathological diagnoses of these 86 cases included cavernomas, metastases, hemangioblastomas, gliomas, and radiation necrosis. Forty-seven of the 86 lesions (54.7%) were small and deep-seated, 34/86 (39.5%) were ill-defined, and 5/86 (5.8%) were small, deep-seated, and ill-defined. Sonograms in the horizontal plane were obtained in all 86 cases. Sonograms in the sagittal plane and in the coronal plane were obtained only in 52 cases and in 46 cases, respectively, due to technical limitation. In 13 cases, sonograms in all three orthogonal planes were available. All lesions were successfully identified and localized by IOUS. Total resection was performed in 67 lesions (77.9%) and partial resection was performed in 19 lesions (22.1%). Conclusions We propose IOUS to be performed in three orthogonal planes when surgery is planned for small, deep-seated, or ill-defined brain lesions. By applying this simple, improved technique, surgeons can perform resection of these lesions precisely.展开更多
文摘Currently, magnetic resonance imaging(MRI) is the only imaging modality available which is capable of acquiring intra-operative images frequently with acceptable spatial and contrast resolution. However, the incorporation of MRI technology into the operating room requires special anesthetic considerations. It may include various aspects such as transport, remote location anesthesia, strong electromagnetic field, use of approved items, equipment counts, possible emergencies, and surgery in awake patients. The patient safety may be compromised by health-related, equipment-related, and procedure-related risks. Direct patient observation may be compromised by acoustic noise, darkened environment, obstructed line of sight, and distractions along with difficult access to the patient for airway management. Most often, the patient's head will be 180° away from the anesthesiologist during the procedure. Several monitors exist that are designed for conditional use in a MR environment. The general design criterion in these monitors is to eliminate conductors that carry electrical signals for monitoring physiologic parameters of the patient. General anesthesia requires an extended anesthetic circuit for ventilation maintenance and drug administration because the patient is located farther from the anesthesia machine than in traditional operating room settings. Dead space creates a time delay before the volatile anesthetic and drugs are administered and when expected effects can be observed. Therefore, the attending anaesthesiologists must understand the above aspects for safe conduct of neurosurgical procedures by minimizing MRI associated accidents while assuring optimal patient vigilance.
文摘The goal in brain tumor surgery is to remove the maxi-mum achievable amount of the tumor, preventing damage to "eloquent" brain regions as the amount of brain tumor resection is one of the prognostic factors for time to tumor progression and median survival. To achieve this goal, a variety of technical advances have been in-troduced, including an operating microscope in the late 1950 s, computer-assisted devices for surgical navigation and more recently, intraoperative imaging to incorporate and correct for brain shift during the resection of the lesion. However, surgically induced contrast enhancement along the rim of the resection cavity hampers interpretation of these intraoperatively acquired magnetic resonance images. To overcome this uncertainty, perfusion techniques [dynamic contrast enhanced magnetic resonance imaging(DCE-MRI), dynamic susceptibility contrast magnetic resonance imaging(DSC-MRI)] have been introduced that can differentiate residual tumor from surgically induced changes at the rim of the resec-tion cavity and thus overcome this remaining uncer-tainty of intraoperative MRI in high grade brain tumor resection.
文摘Background Intraoperative ultrasound (IOUS) has been procedures. In this study, we aimed to evaluate the potential the resection of small, deep-seated, or ill-defined lesions. ncreasingly used as a guiding tool during neurosurgical application of intraoperative ultrasound assisted surgery in Methods Eighty-six consecutive patients with small, deep-seated, or ill-defined intracerebral lesions were studied prospectively. An improved intraoperative imaging technique and surgical setup were practiced during the surgery. IOUS was performed in three orthogonal imaging planes (horizontal, coronal and sagittal). Results Histopathological diagnoses of these 86 cases included cavernomas, metastases, hemangioblastomas, gliomas, and radiation necrosis. Forty-seven of the 86 lesions (54.7%) were small and deep-seated, 34/86 (39.5%) were ill-defined, and 5/86 (5.8%) were small, deep-seated, and ill-defined. Sonograms in the horizontal plane were obtained in all 86 cases. Sonograms in the sagittal plane and in the coronal plane were obtained only in 52 cases and in 46 cases, respectively, due to technical limitation. In 13 cases, sonograms in all three orthogonal planes were available. All lesions were successfully identified and localized by IOUS. Total resection was performed in 67 lesions (77.9%) and partial resection was performed in 19 lesions (22.1%). Conclusions We propose IOUS to be performed in three orthogonal planes when surgery is planned for small, deep-seated, or ill-defined brain lesions. By applying this simple, improved technique, surgeons can perform resection of these lesions precisely.