Survey of American and Canadian general surgeons' perceptions of margin status and practice patterns for breast conserving surgery.

Although breast conservation surgery (BCS) is commonly performed, several aspects of the procedure remain controversial. We undertook a cross-sectional survey to compare Canadian (CDN) and American (AM) general surgeons' reported BCS practice patterns to better understand the cross-border differences in early-stage breast cancer surgery care. A modified Dillman Method survey was mailed to 1,447 AM and 1,443 CDN surgeons.

Practice patterns and perceptions of margin status for breast conserving surgery for breast carcinoma: National Survey of Canadian General Surgeons.

Background: We surveyed Canadian General Surgeons to examine decision-making in early stage breast cancer.

Methods: A modified Dillman Method was used for this mail survey of 1443 surgeons. Practice patterns and factors that influence management choices for: preoperative assessment, definition of margin status, surgical techniques and recommendations for re-excision were assessed.

Effects of the vascular disrupting agent ZD6126 on interstitial fluid pressure and cell survival in tumors.

Interstitial fluid pressure (IFP) is elevated in tumors due to abnormal vasculature, lack of lymphatic drainage, and alterations in the tumor interstitium. ZD6126 is a tubulin-binding agent that selectively disrupts tumor vasculature resulting in tumor necrosis. This study examined the effect of ZD6126 on tumor IFP and the response of tumors with different IFP levels to ZD6126.

Endoscopic Doppler optical coherence tomography in the human GI tract: initial experience.

Background: Expanding the current endoscopic optical coherence tomography (OCT) system with Doppler capability may augment this novel high-resolution cross-sectional imaging technique with functional blood flow information. The aim of this feasibility study was to assess the clinical feasibility of an endoscopic Doppler OCT (EDOCT) system in the human GI tract.

Methods: During routine endoscopy, 22 patients were imaged by using a prototype EDOCT system, which provided color-Doppler and velocity-variance images of mucosal and submucosal blood flow at one frame per second, simultaneously with high-spatial-resolution (10-25 mum) images of tissue microstructure.

Micromachined array tip for multifocus fiber-based optical coherence tomography.

High-resolution optical coherence tomography demands a large detector bandwidth and a high numerical aperture for real-time imaging, which is difficult to achieve over a large imaging depth. To resolve these conflicting requirements we propose a novel multifocus fiber-based optical coherence tomography system with a micromachined array tip. We demonstrate the fabrication of a prototype four-channel tip that maintains a 9-14-microm spot diameter with more than 500 microm of imaging depth.

In vivo Doppler optical coherence tomography of mucocutaneous telangiectases in hereditary hemorrhagic telangiectasia.

Background: Hereditary hemorrhagic telangiectasia is characterized by mucocutaneous telangiectases and visceral arteriovenous malformations. Knowledge is limited concerning the development hemodynamics of mucocutaneous telangiectases. Doppler optical coherence tomography can demonstrate microvascular blood flow at flow rates as low as 20 microm/second, which is up to approximately 100 times more sensitive than Doppler US.

High speed, wide velocity dynamic range Doppler optical coherence tomography (Part III): in vivo endoscopic imaging of blood flow in the rat and human gastrointestinal tracts.

We previously described a fiber based Doppler optical coherence tomography system [1] capable of imaging embryo cardiac blood flow at 4~16 frames per second with wide velocity dynamic range [2]. Coupling this system to a linear scanning fiber optical catheter design that minimizes friction and vibrations, we report here the initial results of in vivo endoscopic Doppler optical coherence tomography (EDOCT) imaging in normal rat and human esophagus. Microvascular flow in blood vessels less than 100 microm diameter was detected using a combination of color-Doppler and velocity variance imaging modes, during clinical endoscopy using a mobile EDOCT system.

High speed, wide velocity dynamic range Doppler optical coherence tomography (Part II): Imaging in vivo cardiac dynamics of Xenopus laevis.

We previously reported a Doppler optical coherence tomography (DOCT) system design [1] for high-speed imaging with wide velocity dynamic range (up to 28.5 dB when acquiring 8 frames per second), operating at 1.3 m with a coherence length of 13.

High speed, wide velocity dynamic range Doppler optical coherence tomography (Part I): System design, signal processing, and performance.

Improvements in real-time Doppler optical coherence tomography (DOCT), acquiring up to 32 frames per second at 250 x 512 pixels per image, are reported using signal processing techniques commonly employed in Doppler ultrasound imaging. The ability to measure a wide range of flow velocities, ranging from less than 20 microm/s to more than 10 cm/s, is demonstrated using an 1.3 microm DOCT system with flow phantoms in steady and pulsatile flow conditions.