斉藤 泰博¹, 山田 有則¹, 吉川 大平¹, 川口 香織¹, 峯田 昌之¹, 秀毛 範至¹, 高塩 哲也¹, 吉田 弘¹, 油野 民雄¹, 鳥谷部 純行²

Yasuhiro SAITOH¹, Tomonori YAMADA¹, Daihei YOSHIKAWA¹, Kaori KAWAGUCHI¹, Masayuki MINETA¹, Noriyuki SHUKE¹, Tetsuya TAKASHIO¹, Hiroshi YOSHIDA¹, Tamio ABURANO¹, Naoyuki TORIYABE²

¹旭川医科大学放射線科, ²旭川医科大学口腔外科

¹Department of Radiology, Asahikawa Medical College, ²Department of Oral Surgery, Asahikawa Medical College

キーワード : Lymph node, Metastasis, Neck, Ultrasonography

We investigated the usefulness of ultrasonography (US) in determining the presence or absence of cervical lymph-node (LN) metastasis. One hundred sixty-nine LNs that had been diagnosed from histopathologic findings from 47 patients with cervical LN metastasis mainly from cancer of the head and neck, were examined. Size, border, and internal echo of the LNs were evaluated on US examination. LN size greater than 10 mm in shortest diameter was a more effective criterion than longest diameter or shortest/longest diameter ratio. Borders were unclear or irregular in 6% of the cases with LN metastasis, though none of the LNs without metastasis had irregular borders. We classified internal echo of LNs into six patterns: homogeneous low (HL), homogeneous high (HH), heterogeneous (HG), central high (CH), eccentric high (EH), or cystic echo (CE) patterns. The HH, HG, and CE patterns were seen mainly in matastatic LNs; the EH pattern, in nonmetastatic LNs. CH and HL patterns were produced by both metastatic and nonmetastatic LNs. While the ratio of HG, and CE patterns increased with length of the shortest diameter, the ratio of the HL pattern tended to decrease. Pathologically, the CE pattern occurred in metastatic LNs, primarily those associated with papillary carcinomas. In the US and corresponding histopathologic findings, echogenic areas in HH, HG, and CH patterns were found to be caused by coagulation necrosis, fibrosis, or keratinization. The eccentric hyperechoic area of nonmetastatic LNs was attributed to fatty tissue. US examination was useful in the diagnosis of metastatic LNs in the cervical region.