Endoscopic tattooing of the colon. An experimental study.

Methods of "tattooing" the colon endoscopically were evaluated in a series of studies on dogs. Injections were performed through a sigmoidoscope using a 25-gauge sclerotherapy needle. The first phase showed excellent staining with methylene blue; however, after 24 hours the stain had completely diffused and was no longer visible. In the second phase, eight agents were evaluated for durability at the site of injection. Only indocyanine green and india ink remained visible on the serosal surface of the bowel after 48 hours. While indocyanine green showed no adverse tissue reaction, india ink caused a significant inflammatory infiltrate with microhemorrhage and thrombosis. The final phase confirmed the staining qualities of indocyanine green. The dye persisted for seven days, and no adverse reactions were noted, either macro- or microscopically. Based on our findings, indocyanine green is an excellent agent for use in tattooing the colon to facilitate intraoperative localization of small colonic lesions. Clinical trials to evaluate the efficacy and safety of this agent in humans are warranted.

The advantages of the 30-cm flexible sigmoidoscope over the 60-cm flexible sigmoidoscope.

To determine the optimal length of the flexible fiberoptic sigmoidoscope we performed a randomized, blinded comparison study of the standard 60-cm instrument with a prototype 30-cm instrument with identical design features. Ninety-six male patients referred for symptom evaluation underwent examination with both instruments in random order by different examiners; positive examinations were followed by colonoscopy or surgery. Performance of the 30-cm sigmoidoscope compared with the 60-cm instrument revealed that the former was significantly more likely to yield a complete examination (74 vs. 32 examinations, p less than 0.002), took less time to perform (6.4 vs. 9.8 min, p less than 0.0001), and was more acceptable to patients and physicians. The 30-cm instrument was not significantly less effective than the 60-cm instrument in detecting polyps (21 vs. 25), adenocarcinoma (six for each), and inflammatory lesions. For these reasons, we conclude that the 30-cm flexible sigmoidoscope has a role in the evaluation of colorectal complaints.

Unusual causes of spontaneous pneumoperitoneum.

Spontaneous pneumoperitoneum may pose a diagnostic dilemma, especially when evaluating a patient who has no or minimal abdominal or constitutional findings accompanying its presence. The free intraperitoneal air may be the result of a perforation of a hollow viscus in such instances. Under these circumstances, the air is most often from another source. The more common sites of origin are intrathoracic sites, air in the wall of the intestinal tract and the genital organs in women. Diagnostic and therapeutic procedures in or adjacent to the abdomen may result in an iatrogenic pneumoperitoneum. In each instance when the findings of an acute abdominal catastrophe are lacking, the circumstances present before the discovery of the pneumoperitoneum should give a clue to the appropriate diagnosis. When a reasonable nonsurgical cause can be discerned, continued observation may be sufficient, thus avoiding an unnecessary laparotomy.