矢島 義昭¹, 宮崎 敦史¹, 枝 幸基¹, 西岡 可奈¹, 渋谷 大助¹, 大平 誠一¹, 長沼 廣²

Yoshiaki YAJIMA¹, Atsushi MIYAZAKI¹, Yoshiki EDA¹, Kana NISHIOKA¹, Daisuke SHIBUYA¹, Seiichi OOHIRA¹, Hiroshi NAGANUMA²

¹仙台市立病院消化器科, ²仙台市立病院病理科

¹Department of Gastroenterology, Sendai City Hospital, ²Department of Pathology, Sendai City Hospital

キーワード : Comet-tail artifact , Cholesterol-crystal stone , Intramural gallstone , ultrasonography

Ultrasonographic examination disclosed diffuse wall thickening and coment-tail artifact in two cases of adenomyomatosis (ADM) of the gallbladder, and laparoscopic cholecystectomy was performed. In case 1, found in a 41-year-old man, the excised gallbladder showed general thickening of the wall and multiple intramural gallstones in the dilated Rokitansky-Aschoff sinuses (RAS). These stones were mainly cholesterol-crystal stones like those described by Yunotani: square, transparent, crystalloid stones with glittering glasslike surfaces; and a smaller number of mixed stones consisting of cholesterol and pigment. Water-bath scan of the removed stones showed only the cholesterol-crystal stones to have the typical comet-tail artifact. Infrared spectrometry of one of the cholesterol-crystal stones showed cholesterol content to exceed 98% , In case 2, found in a 36-year-old man, the excised gallbladder also showed general thickening of the wall, and the dilated RAS contained numerous black intramural stones and several cholesterol-crystal stones. Water-bath scan of the gallbladder showed comet-tail artifacts like those seen in the extracorporal ultrasonogram. Water-bath scan of the removed stones showed only the cholesterol-crystal stones to produce comet-tail artifacts. These results suggest that cholesterol-crystal stones, characteristic of intramural gallstones, may be the origin of the comet-tail artifact seen in ADM of the gallbladder.