Rowe EA, Mathews KG, Linder KE, Tate LP. The effect of photodynamic therapy on cisterna chyli patency in rats.
Vet Surg 2014;
43:642-9. [PMID:
24909350 DOI:
10.1111/j.1532-950x.2014.12222.x]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 04/01/2014] [Indexed: 11/29/2022]
Abstract
OBJECTIVE
To radiographically and histologically evaluate the effects of photodynamic therapy on the cisterna chyli in rats.
STUDY DESIGN
Experimental study.
ANIMALS
Adult male Sprague-Dawley rats (n = 60).
METHODS
Cecal lymph nodes were injected with the photodynamic compound verteporfin. A 690 nm, 500 mW diode laser was then directed at the area of the cisterna chyli for either 0, 1.5, or 3 minutes. Cisterna chyli patency was evaluated using lymphography, and histologic changes were evaluated on postoperative Days 1, 3, 5, 7, and 14.
RESULTS
Histologically, minimal to marked injury to the cisternal and/or pericisternal tissues was present in all treated rats at all time periods. Radiographically, 8/20 cisternae were occluded in the 1.5-minute treatment group (including 1/4 on Day 1, 2/4 on Day 3, 3/4 on Day 5, 0/4 on Day 7, and 2/4 on Day 14), and 9/20 cisternae were occluded in the 3-minute treatment group (including 0/4 on Day 1, 1/4 on Day 3, 3/4 on Day 5, 3/4 on Day 7, and 2/4 on Day 14). There was minimal to no histologic evidence of tissue injury in control rats. All control cisternae were radiographically open.
CONCLUSIONS
Further investigations into the timing of laser application and light dose, or alternative photodynamic agents are required to limit injury to adjacent tissues and to improve the effectiveness of cisternal photoablation.
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