http://repub.eur.nl/res/aut/12183/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/9982/ 2002-01-01T00:00:00Z BACKGROUND: Balloon injury (BI) of the rat carotid artery (CCA) is widely used to study intimal hyperplasia (IH) and decrease in lumen diameter (LD), but CCA's small diameter impedes the evaluation of endovascular therapies. Therefore, we validated BI in the aorta (AA) and iliac artery (CIA) to compare it with CCA. METHODS: Rats underwent BI or a sham procedure (control). Light microscopic evaluation was performed either directly or at 1, 2, 3, 4 and 16 weeks follow-up. The area of IH and the change in LD (LD at 16 weeks minus LD post BI) were compared. RESULTS: In the BI-groups the area of IH increased to 0.14 +/- 0.08 mm2 (CCA), 0.14 +/- 0.03 mm2 (CIA) and 0.12 +/- 0.04 mm2 (AA) at 16 weeks (NS). The LD decreased with 0.49 +/- 0.07 mm (CCA), compared to 0.22 +/- 0.07 mm (CIA) and 0.07 +/- 0.10 mm (AA) at 16 weeks (p < 0.05). The constrictive vascular remodelling (CVR = wall circumference loss combined with a decrease in LD) was -0.17 +/- 0.05 mm in CIA but absent in CCA and AA. No IH, no decrease in LD and no CVR was seen in the control groups. CONCLUSIONS: BI resulted in: (1.) a decrease in LD in CCA due to IH, (2.) a decrease in LD in CIA due to IH and CVR, (3.) no change in LD in AA, (4.) Comparable IH development in all arteries, (5.) CCA has no vasa vasorum compared to CIA and AA, (6.) The CIA model combines good access for 2 F endovascular catheters with a decrease in LD due to IH and CVR after BI. http://repub.eur.nl/res/pub/20058/ 1999-11-03T00:00:00Z The Wellman Laboratories of Photomedicine at the Massachusetts General Hospital in Boston is an internationally known institute for the development and application of laser in medicinco Besides fundamental research which investigates the interaction of light with cells and molecules, a great deal of studies arc performed towards clinical application to treat human diseases. For this reason, all known medical specialties are involved in research programmes examining the use of laser for their purposes: from ophtalmologists, using photodynamic therapy to treat choroidal neovascularization, oncologists to photochemically target and remove breast cancer cells from bone marrow, urologist to detect bladder cancer with fluorescence, gastroenterologists to treat Barret's oesophagus to dermatologists removing latloes and treating multiple skin diseases with the laser. The application of laser to treat vascular diseases was started decades ago, but more recently the concept of photodynamic therapy was introduced by the research group of Dr. LaMuraglia to prevent restenosis. As a research fellow in surgery I joined this group in 1994 and our research goal was to better understand how photodynamic therapy affects the vascular wall. The results from these investigations are presented in tllis thesis. The first part gives an outline of the problem of restenosis, the concept of photodynamic therapy and aims of the study. The following chapters describe how photodynamic therapy interacts with biological factors that regulate the vascular healing process. Finally, considerations for possible clinical use are discussed.