Preoperative Localization of Cystic Lesions in the Knee Using Ultrasound-Guided Injection of Indigo Carmine

Purpose. To evaluate the feasibility and effectiveness of preoperative localization of cystic lesions in the knee using ultrasound-guided indigo carmine injection. Method. Twenty-three cysts in the knee in 23 patients (M:F = 15:8, mean age, 42 years) were localized preoperatively by ultrasound-guided indigo carmine injection. These included 12 meniscal cysts, 7 popliteal cysts, and 4 ganglion cysts. To stain the lesions, 0.2-3 mL of indigo carmine was injected into the cyst using a 22-gauge spinal needle. After localization, the patient was immediately transferred to the operating room and surgery was performed. Intraoperative findings and arthroscopic images were reviewed. Result. All 23 cysts were stained successfully. Twenty cases were confirmed during arthroscopy and 3 cases were confirmed during excisional surgery. There was no significant bleeding/hematoma or anaphylactic reaction. Four patients felt pain during aspiration before indigo carmine injection. The lesions were stained blue and could be clearly identified by the surgeon and were removed arthroscopically or by open surgery. Conclusion. Preoperative localization of cystic lesions in the knee joint region using ultrasoundguided indigo carmine injection is a feasible technique and can be easily and safely be performed. (C) 2010 Wiley Periodicals, Inc. J Clin Ultrasound 38:305-308, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.20682