The advantage of 3D conformal treatment of lumbar spine metastases in comparison to traditional PA or AP-PA techniques: restoring an intermediate niche of therapeutic sophistication.

Background: To evaluate the effect of the 3D radiation field design on normal tissues compared with commonly used appositional fields in patients with lumbar spine metastases.

Methods And Materials: Ten comparative treatment plans for radiation of lumbar spine metastases were compared for posterior and anterior- posterior fields with 3D plans.

Results: The PTV coverage in all comparative plans was similar.

AP-PA field orientation followed by IMRT reduces lung exposure in comparison to conventional 3D conformal and sole IMRT in centrally located lung tumors.

Little attention has been paid to the fact that intensity modulated radiation therapy (IMRT) techniques do not easily enable treatment with opposed beams. Three treatment plans (3 D conformal, IMRT, and combined (anterior-posterior-posterio-anterior (AP-PA) + IMRT) of 7 patients with centrally-located lung cancer were compared for exposure of lung, spinal cord and esophagus. Combined IMRT and AP-PA techniques offer better lung tissue sparing compared to plans predicated solely on IMRT for centrally-located lung tumors.

Multiscale 3D shape representation and segmentation with applications to hippocampal/caudate extraction from brain MRI.

Extracting structure of interest from medical images is an important yet tedious work. Due to the image quality, the shape knowledge is widely used for assisting and constraining the segmentation process. In many previous works, shape knowledge was incorporated by first constructing a shape space from training cases, and then constraining the segmentation process to be within the learned shape space.

Improved treatment of the breast and supraclavicular fossa based on a simple geometrical principle.

In breast cancer, nodal irradiation has become routine, but adds time and creates concerns for field overlap if the "match" is not accurate. We developed a technique to address these issues by using only one isocenter for both areas. Tangents are designed at simulation.

Tracking accuracy of a real-time fiducial tracking system for patient positioning and monitoring in radiation therapy.

Purpose: In radiation therapy there is a need to accurately know the location of the target in real time. A novel radioactive tracking technology has been developed to answer this need. The technology consists of a radioactive implanted fiducial marker designed to minimize migration and a linac mounted tracking device.

Radiosurgical treatment planning of AVM following embolization with Onyx: possible dosage error in treatment planning can be averted.

Treatment of arteriovenous malformations (AVM) of the brain is challenging due to the size and location of the nidus-proper and its proximity to the cerebrovascular circulation. Recent advances in catheter techniques and new embolization materials such as Onyx (a liquid agent that is less adhesive and slowly polymerizing) have increased the probability of achieving obliteration. When planning radiosurgical cases following such embolization, however, one must be cognizant of the distortions introduced by this novel substance on imaging studies.

Limited advantages of intensity-modulated radiotherapy over 3D conformal radiation therapy in the adjuvant management of gastric cancer.

Purpose: Although chemoradiotherapy was considered the standard adjuvant treatment for gastric cancer, a recent Phase III trial (Medical Research Council Adjuvant Gastric Infusional Chemotherapy [MAGIC]) did not include radiotherapy in the randomization scheme because it was considered expendable. Given radiotherapy's potential, efforts needed to be made to optimize its use for treating gastric cancer. We assessed whether intensity-modulated radiotherapy (IMRT) could improve upon our published results in patients treated with three-dimensional (3D) conformal therapy.

Successful use of high dose rate brachytherapy for non-malignant bronchial obstruction.

High dose rate (HDR) endobronchial brachytherapy is a palliative treatment for symptomatic airway obstruction by malignant tumours. We report a novel use of HDR brachytherapy for treating non-malignant bronchial obstruction. The patient had a metal stent placed in a reconstructed airway after a bronchial tear to ensure patency.

Clinical significance of variability of ventricular late potentials detected before discharge in patients after myocardial infarction.

Background: Signal-averaged electrocardiography (SAECG) in patients after myocardial infarction (MI) is widely used to identify patients at risk for ventricular tachycardia (VT) and sudden cardiac death (SCD). It is believed that ventricular late potentials when detected after day 5 after MI are relatively stable and carry the most significant relation to subsequent arrhythmic events. This study sought to determine if ventricular late potentials in patients after MI exhibit variability when recordings were made 10 to 12 hours apart on day 7 and to assess the clinical significance of this variability.

An unusual case of multiple right atrial thrombi in a patient with a dual-chamber pacemaker--a case report.

The authors present an unusual case of multiple large atrial thrombi attached to permanent pacemaker leads identified by transesophageal echocardiography. Pathogenesis, clinical implications, and therapeutic options of pacemaker thrombi are discussed.

A review of erythromycin-induced malignant tachyarrhythmia--torsade de pointes. A case report.

The term torsade de pointes refers to a ventricular tachycardia characterized by QRS complexes of changing amplitude that appears to twist around the isoelectric line and occurs at rates of 200-250/minute. Most cases of torsade de pointes are iatrogenically induced by drugs or electrolyte abnormalities. The most important feature is QT interval prolongation.

Double Orifice Mitral and Tricuspid Valves.

Atrioventricular valve duplication is a rare congenital cardiac anomaly. The anomaly is usually recognized as an incidental finding at autopsy, open heart surgery, or two-dimensional echocardiography. In this article we present the transthoracic and transesophageal presentation of a case of mitral and a case of tricuspid valve duplication.

Comparison of ST-segment/heart rate slope analysis with standard ST-segment measurement criteria to outcome of exercise thallium-201 imaging.

We compared standard ST-segment analysis and ST/HR slope analysis of exercise ECG studies with reference to outcome of exercise thallium-201 studies in 341 patients. Sensitivity was significantly better using ST/HR slope compared with standard ST analysis. Specificity was not significantly different.

A case report of complete heart block caused by non-Hodgkin's lymphoma: the diagnostic role of transesophageal echocardiography.

We present a very rare case of complete atrioventricular block caused by malignant lymphoma diagnosed before death by transesophageal echocardiography. We believe that early detection of metastatic cardiac involvement of tumor is important for proper diagnostic and therapeutic interventions.

Radionuclide simultaneous dual-isotope stress myocardial perfusion study using the "three window technique".

Several methods are available for performing radionuclide stress myocardial perfusion studies. All of these methods require two separate acquisition and processing iterations, which is time-consuming and inconvenient for the patient. The authors introduce a new method using the "three window technique" that they developed to perform simultaneous dual-isotope imaging for stress myocardial perfusion studies.

Intention, perceived control, and weight loss: an application of the theory of planned behavior.

Success at attempted weight reduction among college women was predicted on the basis of a theory of planned behavior. At the beginning of a 6-week period, participants expressed their attitudes, subjective norms, perceived control, and intentions with respect to losing weight. In addition, the extent to which they had made detailed weight reduction plans was assessed, as were a number of general attitudes and personality factors.