Safety and Feasibility Study of Methylene Blue Photodynamic Therapy to Sterilize Deep Tissue Abscess Cavities

Inclusion Criteria: * Adults 18 years or older * If female, patient must have negative pregnancy test * All patients with clinical symptoms (ex: fever, chills, pain, tachycardia, hypotension), laboratory (leukocytosis) and radiologic findings (thick walled, rim-enhancing collection with gas bubbles or air-fluid levels) compatible with an abscess that requires image-guided percutaneous drainage * Abscess cavity diameters will be less than or equal to 8 cm. However, abscess can be complex or loculated * Approval by the primary care team to pursue PDT and discuss enrollment with the patient Exclusion Criteria: * Pregnancy * Lactation * Allergy to contrast media, narcotics, sedatives, atropine or eggs * Necrotic tissue that requires surgical debridement * Severely compromised cardiopulmonary function or hemodynamic instability * Thrombocytopenia (\<50,000/mm3) * Uncorrectable coagulopathy * Poor kidney function (serum creatinine \>3mg/dl) * Lack of a safe pathway to the abscess or fluid collection * Unable or unwilling to understand or to provide informed consent * Unable or unwilling to undergo study procedures * Patient unable to cooperate with, or to be positioned for the procedure * Unable to comply with necessary follow up * Abscesses greater than 8 cm in diameter, multiple separate abscesses in different locations, and abscesses not amenable to safe percutaneous image-guided drainage. * Patient is currently taking serotonergic psychiatric medication