橋本 千樹

BACKGROUND/AIMS: Endoscopic ultrasonography (EUS) is considered the most useful diagnostic modality for regional staging; however, it is still difficult to diagnose lymph node metastasis by EUS images only. In this study, we report the usefulness of contrast-enhanced EUS (CE-EUS) in the evaluation of benign lymph nodes (BLN) or malignant lymph nodes (MLN) based on blood flow patterns. SUBJECTS AND METHODS: In the retrospective study, CE-EUS was performed in 46 patients in whom EUS revealed lymph node in the mediastinum or abdominal cavity. The subjects consisted of 22 patients with BLN and 24 patients with MLN. The lesions were examined by EUS, and the maximal and minimal diameters of lymph nodes were measured. Thereafter, the shape and internal echoes were investigated, and the findings were morphologically classified based on Catalano's report. Enhancement effects and the diagnostic capability of CE-EUS were evaluated. In the prospective study, BLNs were differentiated from MLN using the enhancement patterns on CE-EUS based on the results of the retrospective study, and the diagnostic capability was evaluated. RESULTS: In the retrospective study, there were no significant differences in the maximal diameter and maximal/minimal diameter ratio between MLN and BLN. The morphology was classified into four types. Based on the morphological classification, the sensitivity, specificity, and accuracy rate were 88.2%, 77.3%, and 82.1%, respectively. On CE-EUS, the enhancement pattern was classified into three types. The BLN lesions showed uniform enhancement (19/22). In all patients with MLN, a defect of enhancement was observed (24/24). The sensitivity, specificity, and accuracy rate of CE-EUS were 100%, 86.4%, and 92.3%, respectively. In the prospective study, the sensitivity, specificity, and accuracy rate of CE-EUS were 100%, 81.8%, and 92.0%, respectively. CONCLUSIONS: CE-EUS is useful for differentiating BLN from MLN.

粘液産生性膵管内乳頭腫瘍(IPMT)の存在診断と性状診断,確定診断における体外式超音波検査の役割について述べた.存在診断においては主膵管の拡張と膵管分枝の嚢胞状拡張がキー所見となるが最新の超音波機種を用いればこれは問題がない.性状診断としては,乳頭状隆起(壁在結節)の診断が良悪性の鑑別診断にとっては不可欠であるが,これには超音波内視鏡(EUS)と造影エコー法(CDUS)がよい.われわれは高さが3mm以上の場合には腫瘍性病変,6mm以上では悪性病変として対処している.また悪性病変では深達度診断が必要となり,特に微小浸潤例では膵管内超音波(IDUS)が最も診断能が高い.したがって診断体系からすると,Bモード法,EUS,CEUS,IDUSが診断の要といえよう(著者抄録)

AIM: To estimate the detectability of anomalous connection in pancreatobiliary disease (ACPBD) cases, measuring gallbladder wall blood flow (GWBF). METHODS: In the retrospective study, we enrolled 42 subjects with gallbladder wall thickening. GWBF velocity was determined as an average value of the peak velocity of color signals on the gallbladder wall, three times in each case. Based on the findings on endoscopic ultrasonography (EUS) or endoscopic retrograde cholangiopancreatography (ERCP), the 42 subjects were divided into 11 cases with ACPBD and 31 cases without ACPBD. In the prospective study, the subjects were 92 cases with gallbladder wall thickening. Using the cut-off level of the flow velocity obtained in the retrospective study, the usefulness of measuring GWBF velocity in diagnosing ACPBD was evaluated. RESULTS: In the retrospective study, imaging of GWBF was obtained in 40 of the 42 subjects. The mean GWBF velocity of the ACPBD cases was 29.4+/-3.9 cm/s (mean+/-SD), which was significantly different (P<0.0001; 95% CI 5.48-13.2) from that of the without ACPBD cases (20.1+/-5.9 cm/s). Based on this result, we prepared a receiver operating characteristic curve, and the cut-off level appropriate for diagnosing ACPBD was estimated to be 25 cm/s. In the prospective study, GWBF was detected in 86 of the 92 subjects. Based on the EUS or ERCP findings, the 92 subjects were divided into 15 cases with ACPBD and 77 cases without ACPBD. When a cut-off level of 25 cm/s was employed, ACPBD could be diagnosed with a sensitivity of 87.0% (13/15) and a specificity of 87.3% (62/71). CONCLUSION: Measurement of GWBF velocity, which is less invasive and provides objective values, is very useful for diagnosing ACPBD prior to the development of malignant tumors in cases with gallbladder wall thickening.

BACKGROUND: The differentiation of benign from malignant intraductal papillary mucinous tumors (IPMT) is often difficult even by various examination methods. We evaluated the qualitative and quantitative diagnostic ability of contrast-enhanced transabdominal ultrasonography (CE-US), mainly in differentiating benign from malignant tumors in patients with IPMT. PATIENTS AND METHODS: There were 21 patients with IPMT who underwent CE-US and endoscopic ultrasonography (EUS). Surgery was performed in all 21 patients. Pathological findings were 4 with carcinoma and 17 with adenoma. CE-US was performed using a contrast agent (Levovist; Tanabe, Osaka, Japan) consisting of galactose microbubbles and a small (0.1%) admixture of palmitic acid, and the following items were evaluated by the following procedure. (1) Two reviewers with experienced sonographic and endosonographic ability evaluated CE-US images before and after contrast enhancement and classified the enhancement effects into three grades. In addition, the presence or absence of enhancement effects by CE-US was compared with that of mural nodules visualized by EUS. (2) In all 21 patients, changes in intensity after contrast enhancement were quantitatively measured using an HDI Lab. HDI Lab was provided by ATL (Philips; Bothell, WA) and these software tools rapidly quantify image characteristics within multiple ROI (regions of interest) and make comparisons between several areas or images. In both the early and late phases, the post-enhancement intensity, difference between pre- and post-enhancement intensity, and the percentage change ((post-enhancement value-pre-enhancement value)/pre-enhancement value) were compared between malignant and benign lesions, and the ability of CE-US to differentiate between benign and malignant lesions was evaluated in comparison with the ability of EUS to diagnose the degree of malignancy. RESULTS: (1) In both the early and the late phases, both reviewers observed enhancement effects in all 21 patients. And both reviewers observed mural nodules by EUS in all 21 patients. (2) In all 21 patients who underwent resection of IPMT, the intensity increased in both the early and late phases. When the patients with carcinoma were compared with those with adenoma, the post-enhancement intensity was significantly higher, and the difference between pre- and post-enhancement intensity and the percentage change in the early phase and the late phase was significantly more marked in the carcinoma group (p= 0.019, p= 0.002, p= 0.015, p= 0.012, and p= 0.039, respectively). CONCLUSIONS: CE-US was useful for qualitatively diagnosing tumor lesions in patients with IPMT. Moreover, quantitative changes in intensity can be a parameter for the differential diagnosis of benign and malignant tumors.

31歳男.黒色便,貧血を認め,内視鏡検査で十二指腸乳頭部に腫瘍を認め,紹介入院となる.低緊張性十二指腸造影所見で十二指腸乳頭部に一致して約2cm大の隆起性病変を認めた.超音波内視鏡所見でも十二指腸乳頭部に一致して長径18mm大の腫瘍を認め,その大部分は粘膜下に存在した.腹部造影CT所見でも十二指腸乳頭部に径10mm大の造影効果に乏しい腫瘍を認めた.以上の検査所見より,十二指腸乳頭部カルチノイドで,胆膵管への伸展(-),リンパ節転移(-),遠隔転移(-)と診断し,膵頭十二指腸第二部切除を施行した.病理組織所見では病変部はspindle cell,carcinoid-like cell,ganglion-like cellが混在していた.いずれも異型は認めなかった.免疫組織染色では,ganglion-like cellはS100陽性,carcinoid-like cellはChromogranin A,シナプトフィジンが陽性であった.以上より,十二指腸gangliocytic paragangliomaと診断した

BACKGROUND AND AIM: It is common knowledge that endoscopic ultrasonography (EUS) can accurately diagnose pancreatic diseases. Echoendoscopes for EUS are roughly classified into two categories, the mechanical radial scanning echoendoscope (MR-ES) and the electronic linear array echoendoscope, both of which have their merits and demerits. In 2000, a newly designed echoendoscope, the electronic radial scanning echoendoscope (ER-ES), appeared. The aim of the present study was to compare B-mode image quality between the ER-ES and the MR-ES in pancreatic diseases. METHODS: Patients with pancreatic diseases (30 cystic diseases and 22 solid diseases) underwent EUS with both ER-ES and MR-ES. The B-mode images obtained using both echoendoscopes were graded using a scoring system and statistically analyzed. The assessed point for cystic lesions was the existence of mechanical-noise-like ring-like artifacts derived using multiple reflections ('ring-down'), grating robe and so on, and that for solid lesions was the scale of penetration. The authors compared maneuverability, endurance and endoscopic images between the two types of echoendoscopes. RESULTS: The ER-ES had a significantly higher score than the MR-ES (P < 0.05) in the analysis of both cystic and solid diseases. There was no apparent difference as to maneuverability, endurance and endoscopic images. CONCLUSION: Ultrasound images acquired by ER-ES appear better compared with those acquired by MR-ES.