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Pointing light at soft tissue: clinical applications 79

interstitial fibrosis, and better blood pressure control. the tissue has a chance, you may use LT; the effect will
[252] If these were to be transposed to small animal med- be obvious in few minutes: tissue color and motility (if
icine, the results would be considered promising but working over the intestine) will improve.
the same treatment regime would be quite challenging In a model of renal ischemia (30 minutes) and reper-
in terms of frequency. fusion injury, LT decreased tissue damage when applied
LT can be used as an adjunctive therapy for cystitis, over the kidney area shortly after reperfusion and 1 and
especially for idiopathic cases, due to the anti-inflam- 2 hours later. The protective effect included decreased
matory effect. In my experience, some neurological nitric oxide production and myeloperoxidase activity,
bladders may also benefit from transabdominal LT. In and maintenance of renal tissue glutathione, superox-
the extra-abdominal portion, urethritis is also a good ide dismutase, and catalase levels. Blood urea nitrogen
candidate for LT in cats with feline lower urinary tract and creatinine levels were also lower in the LT group.
disease (FLUTD), especially acute cases. [253] The same research group found LT could protect
For transabdominal treatments, your parameters skeletal muscle from reperfusion injury. [254] But if there
would be as follows (Table 7.8). has been severe sustained hypoxia in the intestines,
once the metabolic balance has shifted to cell death
2
• Starting dose of 4–6 J/cm for a bladder, peritonitis, for good, laser would not be such a good idea (could
or IBD (cat), but if after a couple of treatments there it increase peroxynitrites?); an intestinal ischemia-rep-
2
is no improvement, you may increase to 6–10 J/cm ; erfusion injury model in rats described such deleteri-
2
6–10 J/cm would be the initial dose for kidneys, or ous effects: the cranial mesenteric artery was occluded
treatment of pain related to pancreatitis. for 60 minutes, and LT applied before or immediately
2
• Normally 4–8 W of power are used, up to 10 W in after reperfusion, using 0.5 J/cm in CW over the
larger dogs. serosal surface of the jejunum, in a point-to-point tech-
2
• Use 1–2 W/cm . nique, with a low dose of 0.5 J/cm and very low power
2
2 [19]
density (0.035 W/cm ). The histopathology of the
Your treatment area will be focused over the projec- treated animals initially showed more advanced infarc-
tion area of that organ, but will probably include about tion and damage, although 6 h after reperfusion there
a half of the abdomen at least; for instance, consider were no differences between the treated and control
how the size and projection of the bladder can change group and the animals were not studied further in time
depending on how full it is, and you want to aim at its (could there be a difference after those initial 6 h or by
surface from different angles. The bladder projection using different irradiation parameters?). Interestingly,
area in the cat is proportionally larger than in the dog. despite the more severe local damage shown in the
treated group, LT had a protective effect against sec-
7.9.2 Laser therapy during laparotomy ondary damage to the lung. The protective effect on
lung damage in gut and limb reperfusion injury has
Really? Yes, it can be done. You don’t need to touch been reported by several studies, when LT was applied
the surface of the organs, of course, and you will use over the bronchus. [255, 256]
much less dose, power, and power density: 1–3 J/cm Other examples of the use of LT would be after cys-
2
2
with 0.5–2 W and around 0.1–0.2 W/cm . You can use totomy or intestinal suture (your oncological contrain-
LT to improve blood flow to areas or organs, but as a dications apply here too, though). Once the laparotomy
surgeon, you know reperfusion injury can be fatal and is closed, use LT to improve its healing, and con-
some organs or parts of organs with ischemic damage sider transabdominal therapy benefits, such as those
should not be reperfused, but removed. If you think described in the liver and kidney injury models.

Table 7.8 Recommended parameters for transabdominal treatments.
2
2
Dose (J/cm ) Power (W) Power density (W/cm )
Cat/small dog 4–10 3–6 1–2
Large dog 6–12 4–10 1–2

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