Experimental canine model for sentinel lymph node biopsy in the vulva using technetium and patent blue dye

PURPOSE: This paper aims to study and define the experimental model of sentinel lymph node biopsy of the vulva in bitches. METHODS: 0.2 ml of 99mTc phytate was injected intradermally, using a fine gauge insulin needle in the anterior commissure of the vulva. Thirty minutes after 99mTc injection, the inguinal mapping was performed using a gamma probe. After this, 0.5 ml of blue dye (bleu patente V Guerbet 2.5%) was injected in the same place. After 15 minutes, a 3 cm long inguinal incision was made at point maximum uptake followed by careful dissection, guided by visualization of a bluish afferent lymphatic system that points to the sentinel lymph node (SLN). RESULTS: It was observed that 88% of SLN were identified. It wasn´t found a significant difference among the presence or not of sentinel lymph node in the sides, which is an indication of a good consistency. It was observed a high (88%) and significant (χ2=12.89 and p=0.0003) intercession between both methods (blue dye and radiation). CONCLUSION: The experimental model adopted is feasible, becoming advantageous in applying the association of Patent blue and 99mTc.