Unusual imaging appearances of pancreatic serous cystadenoma: correlation with surgery and pathologic analysis

Background We describe imaging and pathologic features of serous cystadenoma of the pancreas on multislice helical computed tomography CT (MS-CT) and surgical resection. Methods Radiologic and pathologic features were analyzed in five patients. All patients underwent MS-CT and digital subtraction angiography (DSA), and four patients underwent magnetic resonance (MR) imaging. Preoperatively, three cases showed radiologic evidence of mainly solid appearance on MS-CT, and the suspected diagnoses were solid pancreatic tumors (patients 1–3). The other two cases showed radiologic evidence of macrocystic tumor of the pancreas, and the suspected diagnoses were mucinous cystic tumors (cases 4 and 5). All patients underwent surgery, and the diagnosis of serous cystadenoma was confirmed on pathologic examination. Results In three cases that showed a solid appearance on MS-CT, a microcystic appearance was identified on microscopic examination, and the tumors were found to be hypervascular lesions on multiphasic contrast-enhanced CT and DSA. In cases 1 and 2, the lesions showed high intensity with internal septation on T2-weighted MR images. In two cases, the tumors were classified as a macrocystic variant of serous cystadenoma, and no mural nodules, papillary projections, or calcifications were seen in the tumors. Conclusion Imaging appearance of serous cystadenoma on MS-CT is various and sometimes indistinguishable from that of solid tumor or mucinous cystic tumors of the pancreas. Imaging findings of hypervascularity and a well-marginated high-intensity lesion with internal septation on T2-weighted MR imaging may be crucial to identify serous cystadenoma that contains no visible cystic compartments on MS-CT.     

Macrocystic serous cystadenoma of the pancreas: case report

We report a case of macrocystic serous cystadenoma of the pancreas. The lesion consisted of a large main cyst and several small cysts, and each cyst showed high intensity on T1-weighted and very high intensity on T2-weighted magnetic resonance images. High-intensity cyst contents may be a characteristic, if not a specific, finding of macrocystic serous cystadenoma of the pancreas. Received: 24 April 2000/Accepted: 31 May 2000     

Ileal obstruction caused by idiopathic sclerosing encapsulating peritonitis

A 26-year-old woman presented with epigastric pain, vomiting, and a palpable mass in the right lower abdomen. Ultrasonography showed a high echogenic mass associated with a small amount of ascites in the right lower abdomen. Computed tomography demonstrated entrapped ileal loops within a thin-walled fibrous capsule. A thin fibrous sac encasing the terminal ileum was detected on laparotomy and confirmed as idiopathic sclerosing encapsulating peritonitis. RID="ID="<e5>Correspondence to:</e5> M. Y. Kim Received: 25 August 1997/Accepted: 24 September 1997     

Diagnosis of chronic ectopic gestation by hysterosalpingography

Pelvic ultrasound and human chorionic gonadotropin assays are currently the standard methodology to detect tubal pregnancy. We report a case of infertility investigated by hysterosalpingography in which a clinically unsuspected chronic tubal pregnancy was identified with the predisposing factor of bilateral salpingitis isthmica nodosa. The radiographic findings of this very rare cause of tubal filling defect are shown. RID="ID="<e5>Correspondence to:</e5> N. S. Curry Received: 8 July 1997/Accepted: 20 August 1997     

胰腺囊性肿瘤及肿瘤样病变CT诊断及鉴别

目的 探讨胰腺不同性质囊性病变的CT表现特点。方法 回顾性分析、横向对比32例胰腺常见不同性质囊性病变CT特点。所有病例均经CT平扫,23例于平扫后行增强扫描。所有病例经手术病理或随访证实。结果 胰腺浆液性囊腺瘤5例,粘液性囊腺瘤3例,囊腺癌3例,1例胰腺导管内乳头状粘液性肿瘤,2例胰腺真性囊肿,18例假性囊肿。结论 真性或假性囊肿结合病史,诊断不难;而浆液或粘液囊腺瘤与囊腺癌容易相互误诊,应仔细分析其CT表现特点。     

Small hepatic nodules in cirrhosis: ultrasonographic, CT, and MR imaging findings

Purpose: The purpose of this study was to assess the imaging findings of pathologically-proved small hepatic nodules 2 cm in size or smaller detected with ultrasonography in cirrhotic patients with suspected hepatocellular carcinoma (HCC). Materials and Methods: We evaluated sonographically detected 32 small hepatic nodules which were pathologically confirmed in 23 consecutive cirrhotic patients who were suspected of having HCC. Twenty-six lesions were confirmed with ultrasonographically-guided aspiration needle-core biopsy, and six with definitive surgery. Ultrasonographic examination records were retrospectively reviewed. CT, and MR images obtained with various imaging techniques were retrospectively reviewed by two radiologists in a blind fashion. Results: The 32 hepatic nodules were comprised of seven focal fatty changes, two large regenerative nodules, three low-grade dysplastic nodules, five high-grade dysplastic nodules, and fifteen HCCs. Ultrasonography showed various echogenicity for the hepatic nodules. The signal-intensity characteristics with T1-weighted spin-echo, in-phase gradient-recalled-echo, and dynamic MR imagings may be useful in distinguishing HCC from nonHCC nodules. Conclusions: Nearly half of small hepatic nodules detected with ultrasonography were nonHCC nodules. Ultrasonographic findings may not be reliable in characterizing small hepatic nodules in cirrhosis. CT and MR imaging obtained with the various techniques are still insensitive to these hepatic nodules. RID="ID="<e5>Correspondence to:</e5> M. Kanematsu Received: 25 August 1997/Revision accepted: 19 November 1997     

Balloon catheter sphincteroplasty and biliary stone expulsion into the duodenum in patients with an indwelling T tube

Background: To present an alternate approach for treating residual biliary stones in patients with indwelling T tube that uses the immature tract created by the T tube to carry out both sphincteroplasty and expulsion of the calculi with the same angioplasty balloon catheter. Methods: This technique was performed in five patients. Access to the bile duct was through an 8-Fr T tube. First a guidewire was inserted and advanced beyond the obstructing stone to the duodenal lumen. The T tube was removed over the guidewire, and a balloon catheter was introduced. Sphincteroplasty was carried out. Then the balloon was deflated and retracted to a position proximal to the stone. It was then reinflated and used to push the stone, expelling it into the duodenum. Results: In all cases, all biliary stones were expelled without pain, in a single session, and with no immediate complications. All patients showed rapid clinical and analytic improvement. During clinical and echographic follow-up of 2–22 months (mean = 12.4 months), there were no complications or relapses. Conclusions: Our limited experience indicates that sphincteroplasty and expulsion of biliary stones with angioplasty balloon catheters through the T tube immature tract is a simple, safe, low-cost technique that gives good results. RID="ID="<e5>Correspondence to:</e5> J. Muchart Received: 8 September 1997/Accepted: 22 October 1997     

Serous and mucinous cystadenoma/cystadenocarcinoma of the pancreas

Twenty cases of cystic pancreatic neoplasms were examined over a 10-year period by the Department of Radiology, University Hospital, Lund, Sweden. Four patients had serous cystadenoma, seven had mucinous cystadenoma, and seven had mucinous cystadenocarcinoma. One patient had a mucin-producing ductal carcinoma, and one patient had a benign mucus cyst. The various types of tumor are illustrated, and the difficulty in differentiating the subtypes is stressed. Received: 12 July 1999/Accepted: 11 August 1999     

Abdominal tuberculous lymphadenopathy: MR imaging findings

Background: The purpose of this study was to evaluate the utility of magnetic resonance imaging (MRI) as a diagnostic tool in abdominal tuberculous lymphadenopathy. Methods: MRI studies of 11 patients with histologically proven abdominal tuberculous lymphadenopathy were reviewed with regard to anatomic distribution, size, shape, degree, and pattern of enhancement and relation of the lesions to adjacent structures. Results: The most common site of involvement was the periportal area (n= 6), followed by the peripancreatic (n= 5), mesenteric (n= 1), and paraaortic (n= 1) areas. Eight patients were readily diagnosed as having tuberculous lymphadenopathy on abdominal computed tomography. Three patients had a heterogeneously enhancing masslike lesion adjacent to the pancreas and were initially diagnosed as having cystic tumor of the pancreas. On MRI, 11 lesions showed T1 iso- or hypointensity and central T2 hyperintensity. Two lesions showed T1 iso- or hypointensity and central T2 hypointensity. The lesions with different T2 signal intensities showed different patterns of enhancement on contrast-enhanced dynamic studies. The relations between the enlarged lymph nodes and adjacent bile ducts or vascular structrues were well depicted on MRI. Conclusion: MRI was useful in differentiating enlarged lymph nodes abutting the pancreas initially diagnosed as cystic neoplasms on abdominal computed tomography. RID=" ID=" <E5>Correspondence to:</E5> M.-J. Kim Received: 9 May 2000/Accepted: 14 June 2000     

胰腺囊性肿瘤的多层螺旋CT表现与病理对照

目的：探讨胰腺囊性肿瘤的多层螺旋CT（MSCT）表现和诊断价值。方法：回顾性分析21例经手术病理确诊的胰腺囊性肿瘤MSCT表现，其中浆液性囊腺瘤5例，黏液性囊腺肿瘤10例，导管内乳头状黏液瘤3例，实性假乳头状瘤3例。男5例，女16例，年龄14—78岁，平均52岁。使用4层和16层螺旋CT，平扫21例，同时增强20例。结果：①浆液性囊腺瘤多表现为多房囊性肿块，囊壁及分隔厚薄均匀，无壁结节。②黏液性囊腺肿瘤表现为多房或单房、边界清楚、无壁结节或壁结节小；而黏液性囊腺癌浸润周围组织、边界不清、壁结节较大。③导管内乳头状黏液瘤为多房或葡萄串样囊性肿块，与扩张的胰管相通。④实性假乳头状瘤边界清，可有较厚包膜，囊性成分与实性成分构成比例不一，实性部分逐步强化。结论：MSCT可以展示胰腺囊性肿瘤的病理特征，对诊断与鉴别诊断有较高的价值。     

Synchronous mucinous tumors of the ovary and the appendix associated with pseudomyxoma peritonei: CT findings

Background: To present the computed tomographic (CT) findings of synchronous mucinous tumors of the ovary and the appendix associated with pseudomyxoma peritonei (PMP). Methods: Imaging studies, mainly abdominal CT scans, of three women aged 49–75 years were reviewed. Attention was directed to the ovarian masses, peritoneal seeding, and the presence of an appendiceal mucocele. Results: The ovarian tumors and the appendiceal mucocele were clearly demonstrated in two cases, and they were part of the extensive PMP in the third patient. Ascites was found in all cases, with internal septation in one. Associated scalloping of the liver margins and hypodense peritoneal implants, with extensive bowel involvement, were seen in another one. Pathologically, there was one case of right ovarian mucinous cystadenoma and villous adenoma of the appendix, one case of right ovarian and appendiceal mucinous cystadenocarcinoma, and one case of bilateral metastatic ovarian implants of appendiceal mucinous cystadenocarcinoma. PMP was found in all. In the case with benign tumors of the ovary and the appendix, the PMP was classified as a benign mucinous spillage. This patient returned 33 months after surgery with PMP, in which epithelial cells were found. Conclusions: Radiologists should be familiar with the clinical occurrence of synchronous mucinous tumors of the ovary and the appendix associated with PMP and with the typical CT findings of the latter two entities. Alternatively, when the imaging findings suggest ovarian cystic tumor with PMP, the radiologist should be alerted to the probability of a clinically unsuspected appendiceal mucocele and should search for it. Received: 10 August 1999/Accepted: 22 September 1999     

Logistic advantages of four-section helical CT in the abdomen and pelvis

Background: Multisection helical computed tomography (CT) has the potential for providing data sets with better section profiles, more anatomic coverage, and shorter breath-holding periods. Our purpose was to quantitate these advantages in a clinical setting when imaging the abdomen and pelvis. Methods: CT parameters including collimation, timing, z-axis coverage, and milliamperes were gathered retrospectively for the image set of both single-section (GE CT/i with 0.8-s rotation) and four-section (GE QX/i Lightspeed with 0.8-s rotation) helical CT scanners. Data were recorded for the abdomen and pelvis CT (n= 30 each), dual-phase liver CT including the pelvis (n= 15 each), and dual-phase pancreas CT (n= 15 each). Results: The abdominal and pelvic CT averaged 128.4 ± 5.4 s for single-section scanners (70-s delay, two breath-holds of 21.1 and 17.7 s with a 19.5-s interscan delay) and 92.2 ± 2.2 s for the four-section scanner (70-s delay and a 22.2-s breath-hold; p < 0.0001). For the dual liver and pelvis CT, single-section scanners averaged 119.9 ± 7.5 s (30-s delay, 15.8-s arterial phase, 20.0-s interscan delay, 21.2-s venous phase, 19.5-s interscan delay, and 14.2 s for the remaining abdomen and pelvis), whereas the four-section scanner averaged 86.8 ± 2.5 s (30-s delay, 6.7-s arterial phase, 27.9-s interscan delay, and 21.8-s venous phase including the pelvis; p < 0.0001). For the dual pancreas CT, single-section scanners averaged 86.7 ± 2.5 s (20-s delay, 28.3-s arterial phase, 17.8-s interscan delay, 21.7-s venous phase), whereas the four-section scanner averaged 78.0 ± 2.9 s (20-s delay, 9.7-s arterial phase, 30.7-s interscan delay, 13.0-s venous phase; p < 0.0001). Conclusion: CT scanners having four-section technology can reduce overall data acquisition times by 10–30% and total milliamperes by 50–60% depending on the protocol with thinner slice profiles. RID=" ID=" <E5>Correspondence to:</E5> R. C. Nelson Received: 8 December 1999/Revision accepted: 22 March 2000     

胰腺浆液性微囊性囊腺瘤1例报道并文献复习

目的探讨胰腺浆液性微囊性囊腺瘤的临床病理学特征及诊断、鉴别诊断要点。方法对1例胰腺浆液性微囊性囊腺瘤进行临床病理分析及免疫组化研究。结果胰腺浆液性微囊性囊腺瘤临床上可以表现为消瘦、乏力而体格检查阴性；镜下肿瘤由大小不等的囊腔组成，囊壁内衬单层立方上皮，胞质清亮，核小而圆、居中，核分裂象极少见，细胞无异型性，囊腔之间可见粗大的纤维结缔组织分隔。免疫组化瘤细胞keratin和EMA( )，S-100、vjmentir、actin、CGA、Syn、CEA、desmin和Ⅷ因子(-)。结论胰腺浆液性微囊性囊腺瘤是一种罕见肿瘤，其诊断和鉴别诊断主要依靠病理组织学和免疫组化，部分肿瘤的良恶性很难确定，需进行随访。     

Sonographic diagnosis of congenital tuberculosis: an experience with four cases

Abdominal sonography of four infants with pyrexia and hepatomegaly demonstrated multiple hypoechoeic hepatic and splenic foci, guided biopsies of which showed caseating granulomas with acid-fast bacilli. Evidence of tuberculosis in maternal endometrium and its exclusion in the contacts further confirmed a diagnosis of congenital tuberculosis. Clinical suspicion supplemented by careful sonography facilitated early detection and antemortem diagnosis of this potentially fatal disease. RID=" ID=" <E5>Correspondence to:</E5> S. B. Grover, E-81, Kalkaji, New Delhi 110019, India Received: 8 March 2000/Accepted: 19 April 2000     

Fan-shaped hepatic parenchymal damage after ethanol injection therapy for hepatocellular carcinoma: MRI appearances

Background: T1- and T2-weighted magnetic resonance (MR) images frequently show fan-shaped areas of hypo- or hyperintensity in the hepatic parenchyma adjacent to a treated hepatocellular carcinoma after percutaneous ethanol injection (PEI) therapy. These areas correspond to abnormal contrast enhancement on serial dynamic MR images. The purpose of the present study was to describe the location, appearance, and frequency of these abnormalities because it is important to understand these entities for the correct assessment of therapeutic efficacy. Methods: MR imaging including a multisection dynamic study was performed in 20 consecutive patients with hepatocellular carcinoma treated with PEI therapy. We retrospectively evaluated the presence of fan-shaped hypointensities adjacent to treated tumors in the liver parenchyma on T1-weighted images and hyperintensities on T2-weighted images and corresponding fan-shaped contrast enhancement on both arterial-dominant and delayed-phase dynamic MR images. We review the location, appearance, and frequency of these findings, and we discuss the possible causes on the basis of pathologic examinations. Results: Seven (35%) of the 20 patients showed fan-shaped hyperintense areas adjacent to the treated tumors on T2-weighted images. These areas showed isointensity in five patients and hypointensity in two patients on T1-weighted images. Of these seven patients, one (14%) underwent the MR imaging within 1 month after the completion of PEI therapy, and six (86%) had it 2–9 months after the completion of PEI therapy (mean = 6 months). In all seven patients, fan-shaped hyperperfusion abnormalities corresponding to these areas of hyperintensity on T2-weighted images were seen on both arterial-dominant and delayed-phase dynamic MR images. Pathologically, the coagulative necrosis of the hepatocytes with sinusoidal dilatation and the restoration by the development of fibrous tissue were seen in these fan-shaped areas. Conclusion: The fan-shaped areas of abnormal intensity on T1- and T2-weighted images and contrast enhancement on dynamic MR images seem to be attributable to pathologic changes in the normal liver parenchyma induced by the toxic reaction of ethanol. Awareness of the occurrence of such abnormalities in the peripheral liver parenchyma adjacent to the treated tumor is important for the correct assessment of therapeutic efficacy. RID="ID="<e5>Correspondence to:</e5> T. Fujita Received: 24 June 1997/Accepted after revision: 22 October 1997     

Renal angiomyolipoma: evolutional changes of its internal structure on CT

Background: We evaluated interval changes of the internal structure of renal angiomyolipomas in relation to the doubling time on computed tomography (CT). Methods: A retrospective review of 42 renal angiomyolipomas in 10 patients who had been followed up for more than 5 months with CT was performed. The doubling time of each tumor was estimated. We classified the internal structures of the tumors into five types, based on the fat component percentage. We compared changes between initial and follow-up CT, and the relationship with the doubling time was evaluated. Results: The fat component increased more than the soft tissue component in 15 tumors (36%). The soft tissue component increased more than the fat component in only one tumor, in which an intratumoral hemorrhage occurred during the follow-up period. Twenty-six tumors (62%) showed no change. Most tumors with relatively long doubling times did not show a change in their internal structures. Conclusion: The growth of renal angiomyolipoma is due mainly to an increase in its fat component. An increase in the soft tissue component suggests the development of an intratumoral hemorrhage. RID=" ID=" <E5>Correspondence to:</E5> S. Yamamoto Received: 4 February 2000/Accepted: 8 March 2000     

Computed tomography during arterial portography under temporary balloon occlusion of the hepatic artery: evaluation of pseudolesions caused by arterio-portal venous shunts

Background: Computed tomography during arterial portography (CTAP) under temporary balloon occlusion of the hepatic artery (BOHA-CTAP) was introduced to evaluate pseudolesions caused by portal venous impairments such as arterioportal shunt and tumor thrombus. Methods: BOHA-CTAP was performed in seven patients with hepatocellular carcinoma and correlated with clinical outcomes. For patients with wedge-shaped defects suggestive of pseudolesions, BOHA-CTAP was obtained by a 5-F balloon occlusion catheter into the proper hepatic artery through the second 5-F introducer inserted into the common femoral artery a few centimeters below the first 5-F sheath for CTAP. Results: Eight pseudolesions were determined clinically on follow-up CT, ultrasonography, or magnetic resonance imagings. On BOHA-CTAP, five of the eight pseudolesions were eliminated, and two were diminished in comparision with conventional CTAP. One wedge-shaped defect due to tumor thrombus in the portal vein did not show any change. Conclusion: BOHA-CTAP can reduce pseudolesions caused by portal venous impairments and enable the demarcation of the true tumors. RID=" ID=" <E5>Correspondence to:</E5> J. Koizumi Received: 3 August 1999/Revision accepted: 8 March 2000     

Neoplasms containing normal hepatic vessels: imaging features

Background: We investigated the incidence and imaging features of hepatic neoplasms containing normal hepatic vessels. Methods: Among 3183 patients with various hepatic neoplasms, we found nine patients with normal hepatic vessels traversing hepatic neoplasms. The presence of mass effect on the vessel traversing hepatic neoplasms was evaluated. Other suggestive findings of neoplasms such as altered hepatic contour, portal vein thrombosis, mass effect on extratumoral vessel, and bile duct dilatation were analyzed. Results: Thirteen hepatic vessels (nine hepatic veins and four portal veins) extended through hepatic neoplasms in nine patients. Undisturbed hepatic vessels within the neoplasms were found in five patients with either primary or metastatic hepatic neoplasm. In one patient with undisturbed hepatic vessels within the neoplasm, there were no associated abnormal findings such as biliary dilatation, change of hepatic contour, or any changes involving the vessels external to neoplasms. Conclusion: Although rare, various primary and secondary hepatic neoplasms can have normal hepatic vessels passing through them without mass effect. However, correct diagnosis in most neoplasms would be possible with careful examination of associated findings. RID=" ID=" <E5>Correspondence to:</E5> J. K. Han Received: 2 February 2000/Accepted: 5 April 2000     

Catheter dislodgement of percutaneous transhepatic biliary drainage: identification of role of puncture sites and catheter sheath

Background: To identify the appropriate puncture points in the bile duct to avoid catheter dislodgement. Methods: Percutaneous transhepatic biliary drainage catheters (n = 300) were placed in 242 patients. The frequency of dislodgement (complete dislodgement or bending of the catheter) was prospectively investigated. The puncture site of the bile duct was classified on the ultrasonographic findings as follows: Main-B3, main branch of the lateral inferior segment; peripheral-B3, peripheral branch of the lateral inferior segment; B2, lateral superior segment; left hepatic duct, proximal portion of the left hepatic duct; B8, anterior superior segment; B5, anterior inferior segment; B5 + 8, main bile duct of the anterior segment; B6, bile duct of posterior inferior segment; and right hepatic duct, proximal portion of the right hepatic duct. Results: When a catheter without an outer sheath was used, catheter dislodgement in peripheral-B3 (2/11, 18%) was more common than in main-B3 (0/32, 0%; p < 0.05). In B5, catheter dislodgement (6/12, 50%) was more frequent than in B8 (3/20, 15%; p < 0.05) and in B6 (0/14, 0%; p < 0.005). When a catheter with an outer sheath was used, catheter dislodgement (2/207, 1%) was rare. Conclusion: Drainage from B5 and peripheral-B3 is associated with a high risk of dislodgement of the catheter. A catheter with an outer sheath was useful to prevent catheter dislodgement. RID=" ID=" <E5>Correspondence to:</E5> K. Tamada Received: 8 February 2000/Accepted: 8 March 2000     

Late-phase enhancement of the upstream portion of pancreatic adenocarcinoma on dual-phase helical CT

Background: Late-phase enhancement of pancreatic parenchyma upstream (tail side) of pancreatic adenocarcinoma is found frequently on dual-phase helical computed tomography (CT). We measured the frequency of late-phase enhancement of the upstream portion of pancreatic adenocarcinoma and normal pancreatic parenchyma using dual-phase helical CT. Methods: Twenty-one patients with pancreatic adenocarcinoma and nontumorous pancreas upstream of tumors were compared with 100 control patients without pancreatic disease. Early and late scans started at 25 and 75 s, respectively, after intravenous injection of contrast material. The attenuation values of normal and nontumorous pancreas upstream of tumors were assessed in three phases: precontrast, early, and late enhanced. Enhancement ratio (ER) was calculated as ER = (late phase − precontrast)/(early phase − precontrast). Results: Late-phase enhancements (ER > 1.0) were seen in 86% of upstream pancreas and 10% of normal pancreas. The mean ER of upstream pancreas was significantly higher than that of normal pancreas (p < 0.01). Conclusion: Late-phase enhancement of the pancreas upstream of the tumor is frequently observed in patients with pancreatic adenocarcinoma. Late-phase enhancement and histology showed a correlation for chronic obstructing pancreatitis in five patients. Received: 30 October 2000/Revision accepted: 7 February 2001