Seong Tai Hahn

Gallbladder wall thickening: MR imaging and pathologic correlation with emphasis on layered pattern.

The aim of this study was to correlate MR findings of gallbladder wall thickening with pathologic findings on the basis of the layered pattern and to evaluate the diagnostic value of MR imaging in gallbladder disease. We retrospectively evaluated the source images of HASTE sequences for MR cholangiography in 144 patients with gallbladder wall thickening. The layered pattern of thickened wall was classified into four patterns. Type 1 shows two layers with a thin hypointense inner layer and thick hyperintense outer layer. Type 2 has two layers of ill-defined margin. Type 3 shows multiple hyperintense cystic spaces in the wall. Type 4 shows diffuse nodular thickening without layering. MR findings of a layered pattern of thickened gallbladder were well correlated with histopathology. Chronic cholecystitis matched to type 1, acute cholecystitis corresponded to type 2, adenomyomatosis showed type 3, and the gallbladder carcinomas showed type 4. All four layered patterns were associated with PPV of 73% or greater, sensitivity of 92% or greater and specificity of 95% or greater. Our results indicate that MR findings of gallbladder wall thickening are characteristic in each entity and correlate well with pathologic findings. The classification of the layered pattern may be valuable for interpreting thickened gallbladder wall.

Characteristic MR findings of cervical pregnancy

The aim of this study was to define the characteristic MR findings of cervical pregnancy. Twelve patients with cervical pregnancy underwent MRI because of difficulty in the diagnosis by ultrasonography, human chorionic gonadotropin assessment, and other clinical evaluations. The assessment of MRI included size and location of the lesion, margin, MR signal intensity, rim of low‐signal intensity, enhancement pattern, appearance of enhancing solid component, parametrial change, endometrial change, pelvic fluid collection, and ovarian change. All cases showed ill‐marginated mass with very heterogeneous signal intensity on T2‐weighted images, irregular internal high‐signal intensities on T1‐weighted images, a partial or circumferential rim of low‐signal intensity, dense irregular peripheral enhancement and enhancing papillary solid components with accompanying tubular signal voids, and variably increased parametrial vascularities. This heterogeneous hemorrhagic mass with densely enhancing papillary solid components may be the typical MR finding for cervical pregnancy. J. Magn. Reson. Imaging 2001;13:918–922.

Intraarterial Lidocaine Administration for Relief of Pain Resulting from Transarterial Chemoembolization of Hepatocellular Carcinoma: Its Effectiveness and Optimal Timing of Administration

AbstractPurpose: Patients undergoing transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) commonly have significant post-procedural abdominal pain necessitating narcotic administration. It is known that intraarterial administration of lidocaine is effective in controlling the pain during the procedure. However, optimum timing of the lidocaine administration is not precisely known. The purpose of this study was to assess the efficacy of intraarterial lidocaine administration for control of pain resulting from TACE and to evaluate the optimal timing of administration. Methods: In a prospective trial, 113 consecutive patients with HCC who underwent TACE were classified into three groups: those who received a lidocaine bolus intraarterially immediately prior to TACE (group A, n = 30), those who received lidocaine immediately after TACE (group B, n = 46), and those who did not received lidocaine (group C, n = 37). Incidence and degree of post-procedural pain was assessed using a subjective method (visual analogue scales scored from 0 to 10) and an objective method (amount of post-procedural analgesics). Results: The incidence of post-procedural pain in group A (16.7%) was significantly lower than that of group B (38.3%; p = 0.005). The mean pain score was 3.0 in group A and 4.8 and 3.1 in groups B and C, respectively. The mean dose of analgesic used after the procedure in group A (25.0 mg) was significantly lower than those in group B (52.9 mg) and group C (41.0 mg; p = 0.002). Conclusions: Pre-TACE intraarterial administration of lidocaine is much more effective than post-TACE administration in reducing the incidence and the severity of post-procedural pain. Furthermore, in order to reduce the incidence of post-procedural pain and dose of post-procedural analgesics, we recommend routine pre-TACE administration of lidocaine because post-procedural pain might developed even in patients who did not feel any pain during the TACE.

Bronchiolitis obliterans after allogenic bone marrow transplantation: HRCT findings.

Objective To evaluate the high resolution computed tomography (HRCT) findings of bronchiolitis obliterans (BO) after bone marrow transplantation (BMT). Materials and Methods During the past three years, 11 patients were diagnosed as having BO after BMT when they developed irreversible air flow obstruction, with an FEV1 value of less than 80% of the baseline value, without any clinical evidence of infection. All 11 patients underwent HRCT, of whom eight also underwent follow-up HRCT. The HRCT images were assessed retrospectively for the presence of decreased lung attenuation, segmental or subsegmental bronchial dilatation, diminution of peripheral vascularity, centrilobular nodules, and branching linear structure on the inspiratory images. The lobar distribution of the decreased lung attenuation and bronchial dilatation was also examined. The presence of air trapping was investigated on the expiratory images. The interval changes of the HRCT findings were evaluated in those patients who had follow-up images. Results Abnormal HRCT findings were present in all cases; the most common abnormalities were decreased lung attenuation (n=11), subsegmental bronchial dilatation (n=6), diminution of peripheral vascularity (n=6), centrilobular nodules or branching linear structure (n=3), and segmental bronchial dilatation (n=3). Expiratory air trapping was noted in all patients. The decreased lung attenuation and bronchial dilatations were more frequent or extensive in the lower lobes. Interval changes were found in all patients with follow-up HRCT: increased extent of decreased lung attenuation (n=7); newly developed or progressed bronchial dilatation (n=4); and increased lung volume (n=3). Conclusion HRCT scans are abnormal in patients with BO, with the most commonly observed finding being areas of decreased lung attenuation. While the HRCT findings are not specific, it is believed that their common features can assist in the diagnosis of BO in BMT recipients.

Preliminary experience using high intensity focused ultrasound for treating liver metastasis from colon and stomach cancer

Purpose: To determine the efficacy and safety from our preliminary results of using high intensity focused ultrasound (HIFU) to treat liver metastasis from colon and stomach cancer. Materials and methods: Ten patients with liver metastasis from colon cancer and three from stomach cancer underwent HIFU under general anesthesia. HIFU was performed using an extracorporeal, ultrasound-guided focused system. Complications during the study, extent of coagulative necrosis at two-week follow up, and evidence of tumor on further follow up were analyzed. Patients were divided into four categories: (I) complete ablation with no evidence of recurrence on follow up; (II) apparent complete ablation of target mass with new foci of disease in the target organ or distant malignancy and no local tumor progression; (III) local tumor progression after apparent complete ablation; (IV) partial ablation. Results: Mean follow-up period was 22 weeks in the colon cancer group and 58 weeks in the stomach cancer group. The sum of total lesion size was between 1.8 cm and 21.4 cm (mean: 8.4 cm ± 6.7 cm) for the colon cancer group and between 1.7 and 16.3 cm (mean: 8.8 cm ± 7.3 cm) for the stomach cancer group. In the colon cancer group, one patient was categorized as category I, one as category II, three as category III, and the remaining five as category IV. The stomach cancer group showed two patients as category I, and one as category II. Conclusion: For treating liver metastasis from colon and stomach cancer HIFU seems safe but its efficacy is questionable. Further research is warranted.

Teratoma with Malignant Transformation in the Anterior Mediastinum: A Case Report

Malignant transformation of teratoma in the anterior mediastinum is rare; the mass usually has a long history and is seen in older patients. We report a case of teratoma with malignant transformation in the anterior mediastinum, complicated by rupture. CT revealed a lobulated, inhomogeneous cystic mass with a fat component and wall calcifications. The lateral wall was disrupted and consolidation in the adjacent left upper lobe was noted, suggesting rupture. A heterogeneously enhanced solid portion, obliterating the fat plane between the mass and the great vessels was present in the medial aspect of the mass, and pathologic examination demonstrated the presence of adenocarcinoma.

Recurrence after Percutaneous Ethanol Ablation of Simple Hepatic, Renal, and Splenic Cysts: Is It True Recurrence Requiring an Additional Treatment?

Background: Recurrence after percutaneous ethanol ablation (PEA) of benign hepatic and renal cysts has been common, resulting in re-treatment or additional surgery. However, in recent years, a few cases of spontaneous regression of recurrent cysts following PEA have been experienced, which led to the design of this study to evaluate cyst recurrence after PEA and the necessity of additional treatment. Purpose: To evaluate whether the initial recurrence after PEA of benign hepatic, renal, and splenic cysts is true recurrence, and to decide whether additional treatment is needed. Material and Methods: Thirty-nine benign cysts (21 hepatic, 17 renal, and one splenic) were treated with PEA. PEA was performed with injection of 13–900 ml (40–50% of the volume of aspirated fluid) of absolute ethanol into the cysts. For cysts larger than 100 ml, two or more PEAs were given in one session. Ultrasonography was then performed during a period of 12 months with 1–2-month intervals. Results: Two months after PEA, eight cysts (20.5%) regressed completely; another 31 cysts recurred with decreased size. After 6 months, 10 of the recurrent cysts had regressed spontaneously. Another four recurrent cysts regressed after 8 months, and three regressed after 12 months. Hence, 25 out of 39 (64.1%) cysts regressed within 12 months after PEA. The mean regression time of the 25 recurrent cysts was 6.3 months. All recurrent cysts, including the 14 that were lost to complete follow-up, showed gradual decrease overtime. There were no major complications associated with PEA. Conclusion: Initial relapse of a cyst following PEA does not signify true recurrence, but transient, reactive, or inflammatory fluid collections which eventually disappear within several months, and thus does not necessitate additional treatment.

Breast MRI findings after modified radical mastectomy and transverse rectus abdominis myocutaneous flap in patients with breast cancer

To evaluate the MRI findings in breast cancer patients who had undergone a modified radical mastectomy (MRM) and a transverse rectus abdominis myocutaneous (TRAM) flap.

Comparison of complications between transjugular and axillosubclavian approach for placement of tunneled, central venous catheters in patients with hematological malignancy: a prospective study

This study was designed to compare the incidence of mechanical, thrombotic and infective complications in transjugular (IJV) and axillosubclavian (SCV) central venous catheters (CVC) in patients with hematological malignancy. In a prospective observational trial, 131 consecutive patients were classified into two groups: Group A included those with IJV catheter insertions under sonography guidance (n=61) and group B included those with SCV insertions under venography guidance (n=70). After catheter placement, patients were prospectively acquired and recorded to obtain the following data: success rates, total catheter days, and complication episodes per 100 catheter days. All procedures were technically successful. Total catheter days were 7800 (group A) versus 8391(group B). Mechanical complications were observed in three cases from group A and 11 from group B, with an incidence rate of 0.04 per 100 catheter days versus 0.13 (P=0.043), respectively. Two symptomatic thrombotic complications were observed in group B. The number of infective complications was not significantly different between the two groups (P=0.312). There was no difference in infective complication incidence between the two groups. To minimize catheter-related mechanical and thrombotic complications, however, the IJV approach is superior to the SCV approach.

Renal artery embolization controls intractable pain in a patient with polycystic kidney disease

A 65-year-old man with adult polycystic kidney disease (APKD) and chronic renal failure suffered from intractable abdominal pain and distension for 2 weeks. Meperidine infusion did not alleviate his pain. However, pain and abdominal distension were successfully controlled by embolization of both renal arteries.