Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0155339 (Brown)
 12,436 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Twenty-six patients with recurrent or unremovable malignant gliomas were treated by interstitial brachytherapy with iridium-192 seeds. Stereotactic implantation of the afterloading catheters using the Brown-Roberts-Wells computed tomography (CT)-guided stereotactic system was performed in 24 patients and surgical implantation in two patients with pontine glioma. The response to therapy was measured by serial CT, magnetic resonance imaging, and clinical examination. Tumor regression was seen in 17 patients 1-3 months after implantation. Tumor progression was seen in only three patients. After interstitial brachytherapy, the most commonly observed CT finding was central low density. Median survival time was 18 months after implantation. Autopsies in five patients revealed the delayed effects of radiation injury such as typical vascular changes, microcalcification, and coagulative necrosis in the implant area and tumor recurrence at the periphery. The results suggest that brachytherapy is not curative but prolonged the median survival time by 6 months.
 ...
PMID:Preliminary results of interstitial 192Ir brachytherapy for malignant gliomas. 128 Jul 75

The Gill Thomas Locator is a stereotactic adaptor for the Brown-Roberts-Wells and Cosman-Roberts-Wells systems. It is a noninvasive device that relies on temporary fixation to the maxillary teeth. A series of 20 patients have had stereotactic biopsies with this system. A diagnostic biopsy was obtained in 19 cases. The frame was well tolerated, accurately relocatable, and allowed computed tomographic scanning and surgery to be conducted at different times.
 ...
PMID:Early experience with the Gill Thomas Locator for computed tomography-directed stereotactic biopsy of intracranial lesions. 133 49

The purpose of incorporating stereotactic methodology into neurosurgical procedures is to consistently achieve a high degree of accuracy and precision in localizing intracranial targets. Therefore, the limits of resolution for the therapeutic intervention itself are a function of the accuracy and precision inherent to the particular stereotactic frame system itself. The total clinically relevant error (application accuracy) comprises errors associated with each procedural step, including imaging, target selection, vector calculation and the mechanical errors of stereotactic frames. To evaluate these parameters, a systematic error analysis was carried out in the 4 most commonly used CT-compatible stereotactic devices: the Brown-Roberts-Wells, Cosman-Roberts-Wells, Kelly-Goerss Compass (modified Todd-Wells) and Leksell frames. Over 7,681 independent test measurements were made. The results suggest a potentially significant degree of error in application accuracy of all stereotactic instrumentation which is accentuated by imaging-associated error. These individual error values must be considered with every clinical use of stereotactic frames.
 ...
PMID:An independent application accuracy evaluation of stereotactic frame systems. 143 25

Machine vision techniques (video cameras) can be used to determine the three-dimensional position of objects. This transformation can be accomplished with standard mathematical algorithms. Initial accuracy tests of stereotactic localization with video cameras were performed using a standard Brown-Roberts-Wells (BRW) phantom simulator coupled with the BRW angiographic localizer. Localization accuracy was within 1.5 mm. Potential applications of machine vision techniques include freehand stereotactic localization of the position and orientation of surgical instruments. With sufficient computer speed these techniques can be used for continuous monitoring of the position of instruments within the cranial vault.
 ...
PMID:Stereotactic localization and guidance using a machine vision technique. 143 58

The authors describe a new method for reproducible, non-invasive fixation of a stereotaxic localizing frame. A localizing system similar to that of Brown-Roberts-Wells for MR can be fixed at the base of the facial skeleton to the upper dental arch by an orthodontic resin plate. Results of trials with CT scan, advantages and disadvantages are discussed. The new fixture could be employed in open surgery and in fractionated radiotherapy.
 ...
PMID:A new model for non-invasive, reproducible fixation of a stereotaxic frame using an orthodontic resin plate. Technical note. 145 99

Electrodes placed stereotactically in mesial temporal lobe structures may be useful for determining laterality, and extent of the epileptogenic zone in temporal lobe epilepsy. We present and compare our experience with the use of two stereotactic arcs, the Brown-Roberts-Wells (BRW) and Cosman-Roberts-Wells (CRW) for magnetic resonance imaging guided placement of multicontact electrodes in the amygdala, anterior and posterior hippocampus. Out of 101 electrodes, 28 were placed in 6 and 17 patients using the BRW and CRW arcs, respectively. The target-centered design of the CRW arc eliminated the need for trajectory calculations, used uniform 'depth' measurements, and allowed greater operative flexibility and a shortened operating time. The use of depth electrode recording allowed 14 of the 23 patients to be selected for temporal lobectomy.
 ...
PMID:MRI-guided stereotactic placement of depth electrodes in temporal lobe epilepsy. 156 99

The authors present a simple software written in Turbo Pascal which allows placement of multiple parallel sources for interstitial brachytherapy using the Brown-Roberts-Wells CT stereotactic system. The user can choose any direction in space, independently from the CT plane, and any number of linear sources arranged on one or more hypothetical cylinders of variable radius. The sources can be rotated on the cylinder in order to avoid critical structures. This small program runs on any IBM compatible computer.
 ...
PMID:A software tool to assist placement of multiple parallel brachytherapy sources using the Brown-Roberts-Wells stereotactic system. 156 1

In the operative resection of brain tumors, defining and locating edges of deep-seated tumors or those with indistinct color and consistency can be difficult. This report presents a simple yet precise, alternative method, using the basic Brown-Roberts-Wells or Cosman-Roberts-Wells stereotactic frame, for placement of visual markers to aid in tumor resections. The method can also be extended to the Leksell system. Using routine computed tomographic scanning or magnetic resonance imaging after stereotactic frame application, multiple points along tumor edges were used as target points. In the operating room, standard techniques were used for the skin incision, removal of the bone flap, and opening the dura. At each target point, after opening the dura and using stereotactic coordinates and equipment, a microbiopsy forceps was used to place "micropatties" (each with a string tail) or small catheters with pledgets or catheter tips located at tumor edges. After removing the arc, the tumor resection was accomplished in a conventional nonstereotactic manner by simply following string tails or catheters to the tumor. Gross tumor edges were determined from positions of actual patties or catheter tips. These simple but accurate techniques offer the possibility of tumor resections under stereotactic guidance with equipment readily available to most neurosurgeons. The fidelity of marker placement is also maintained in relation to tumor edges despite shifts in the tumor and/or brain as cystic areas are drained or large amounts of the tumor are resected.
 ...
PMID:Brain tumor resection aided with markers placed using stereotaxis guided by magnetic resonance imaging and computed tomography. 164 77

Experience with a consecutive series of 125 computerized tomographic (CT) image guided stereotaxic neurosurgical procedures, performed using the Brown-Roberts-Wells (BRW) system is described. Operative objectives included tissue sampling for diagnostic purposes, intra-operative localization of craniotomy flaps and intracerebral lesions, cyst and abscess aspiration and lesion to modulate tremor. A neuropathological diagnosis was possible in 96% of the biopsies, and lesions were precisely localized in all patients undergoing microsurgical stereotaxic craniotomy. Two patients (2.2%) undergoing stereotaxic biopsy died as a result of the procedure and one patient's hemiparesis was permanently worsened (0.8%). In only one of three patients undergoing stereotaxic thalamotomy was tremor abolished. This report confirms that CT image guided stereotaxic neurosurgery is safe, accurate and versatile. There is, however, a moderate incidence (7.2%) of lesser complications that can occur with this type of surgery. These complications, which are emphasized in this paper, are related to both the site of surgery and the neuropathology.
 ...
PMID:CT-guided stereotactic neurosurgery using the Brown-Roberts-Wells system: experience with 125 procedures. 175 73

Initial experience with the Brown-Roberts-Wells (BRW) computed tomographic (CT)-guided stereotactic system is reported. Forty-two procedures were performed over a 22-month period on 21 female and 20 male patients (one patient had a repeat procedure). Their ages ranged from 11 years to 89 years. These included 21 stereotactic biopsy procedures, 2 stereotactic implantations of third ventricular catheters through the foramen of Monro for intraventricular opiate insertion in terminal cancer patients, 2 stereotactic aspirations for brain abscess, 10 stereotactic aspirations of intracerebral haematomas, 3 stereotactic aspirations of cystic brain tumours, 1 stereotactic placement of a fourth ventricle-peritoneal shunt and lastly 3 stereotactic craniotomies. Successful targeting was achieved in all cases. There was one operation-related complication which resulted in uncontrollable intracerebral haemorrhage and ultimately led to the patient's demise.
 ...
PMID:CT-directed BRW stereotactic neurosurgery: local experience with 42 cases. 178 71


1 2 3 4 5 6 7 8 9 10 Next >>