野田 弘志¹, 白浜 正文², 中尾 多香昭², 古川 次男¹, 井島 宏¹, 岡 直剛¹, 入江 康司³

Hiroshi NODA¹, Masafumi SHIRAHAMA², Takaaki NAKAO², Tsugio FURUKAWA¹, Hiroshi IJIMA¹, Naokata OKA¹, Kohji IRIE³

¹佐賀県立病院好生館外科, ²佐賀県立病院好生館内科, ³佐賀県立病院好生館病理

¹Department of Sugery, Saga Prefectural Hospital, ²Department of Internal Medicine, Saga Prefectural Hospital, ³Department of Pathology, Saga Prefectural Hospital

キーワード : Epidermoid cyst, Spleen, Ultrasound

A 48-year-old woman visited this institution because of pain in the left upper quadrant. A mass that was palpable but not tender was discovered at the left subcostal region on physical examination, and subsequent imaging studies produced four main findings. First, abdominal plain x-ray film showed a round calcified mass in left upper quadrant. Second, ultrasound examination showed a remarkably large cystic mass with a calcified rim near the lower pole of the spleen. There was layering of two fluids within the cyst: one was almost anechoic; the other was echogenic. The interface between the two fluids was disarranged and fine bright echoes were scattered throughout the cystic mass when the patient's position was changed. Third, CT scan showed a homogenous mass that had water density and measured 9 cm in diameter at the lower pole of the spleen. Calcification of the wall was also noted. Fourth, T1- and T2- weighted MR images of the abdomen showed a spherical mass with a smooth wall and homogeneously low and high intensity, respectively. The mass was diagnosed as a splenic cyst, and splenectomy was performed. Histologic exploration of the mass showed it to be an epidermoid cyst. The sonographic characteristics of this splenic epidermoid cyst are described here.