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Successful closure of gastrocolic fistula using preoperative localization with charcoal nanoparticles tattooing.

A 53-year-old man presented with chronic diarrhea, upper abdominal pain, and weight loss. Diarrhea occurred 10 times per day. Laboratory tests revealed a leukocyte count of 13.1*109/L, hemoglobin count of 105.0 g/L, and albumin count of 31.0 g/L. Fiber gastroscopy and upper gastrointestinal contrast both showed a fistula between the stomach and descending colon (Figure 1). Because of duodenal ulcer, he underwent two major gastrointestinal reconstruction surgeries 5 years ago. Therefore, severe ankylenteron was suspected. Preoperative localization was performed using charcoal nanoparticles tattooing. One week before surgery, charcoal nanoparticle (Carbon Nanoparticles Suspension Injection, Lummy) was injected 0.5 cm distal to the anastomosis through an endoscope using a 26 G needle (Olympus injector nm200U-0423, Olympus) (Figure 2). The injection dose was 0.5 mL (5 mg). During the surgery, we found that ankylenteron was serious exceedingly. The bowel marked with the charcoal nanoparticle could be easily located (Figure 3). After locating the staining point, the gastrocolic fistula could be quickly located, and the surgery was completed within 1 h. During a subsequent follow-up, his condition has markedly improved. The patient received written informed consent. In recent years, preoperative localization technology (such as metal clip, indocyanine green, methylene blue, and India ink) has been gradually used in various surgical procedures (1). However, metal clips are usually small and may be difficult to palpate. In addition, because of the peristalsis of the intestine, the metal clip may fall off and cause the failure of localization during surgery. India ink cannot be retained for long periods and may become invisible. Further, India ink and several nano dyeing agents may cause inflammation, allergic reactions, and other adverse events (2).