Mepolizumab improves sense of smell in severe chronic rhinosinusitis with nasal polyps: SYNAPSE

BACKGROUND

Loss of smell is one of the most bothersome and difficult-to-treat symptoms in patients with severe chronic rhinosinusitis with nasal polyps (CRSwNP).

METHODOLOGY

SYNAPSE was a 52-week Phase III study of 4-weekly mepolizumab (100 mg subcutaneously) plus standard of care in adults with severe bilateral CRSwNP. This post hoc analysis assessed changes from baseline to study end in loss of smell visual analogue scale (VAS) symptom score, in patients stratified by several baseline clinical characteristics. SinoNasal Outcomes Test (SNOT)-22 sense of smell/taste item and University of Pennsylvania Smell Identification Test (UPSIT) scores were also assessed.

RESULTS

SYNAPSE enrolled 407 patients (mepolizumab=206; placebo=201) with impaired sense of smell at baseline. Improvements from baseline to study end in loss of smell VAS score were greater with mepolizumab versus placebo (treatment difference: -0.37) and most notable in patients with fewer or more recent prior surgeries (treatment difference: 1 vs 2 vs >2 prior surgeries,-1.29 vs -0.23 vs -0.07.

Two-year outcomes of radiofrequency device treatment of the nasal valve for nasal airway obstruction

BACKGROUND

Temperature-controlled radiofrequency (TCRF) device treatment of nasal valve dysfunction (NVD) was superior to a sham procedure control in reducing the symptoms of nasal airway obstruction (NAO) in this randomised controlled trial (RCT).

METHODOLOGY

Two-year outcomes for 108 patients actively treated in a prospective, multicenter, patient-blinded RCT were used to determine treatment effect durability and changes in medication/nasal dilator usage. A responder was defined as ≥20% reduction in NOSE score or ≥1 reduction in severity class.

RESULTS

The mean (SD) age of patients was 48.5 (12.3) years; 66 (61.1%) women. Baseline NOSE score was 76.3. The 2-year responder rate was 90.4% and NOSE score treatment effect was -41.7; 54.7% improvement. Of 57 patients using medications/nasal dilators at baseline, 45 (78.9%) either stopped all use (33.3%) or stopped/decreased (45.6%) use in ≥1 class at 2 years. Concurrent septal deviation, septal swell body, or turbinate enlargement did not significantly affect the odds of exhibiting a NOSE score of ≤25 at 2 years.

CONCLUSIONS

TCRF device treatment of NVD resulted in significant and sustained improvements in the symptoms of NAO at 2 years, accompanied by a substantial reduction in medication/nasal dilator use.

Comparison of nasal valve dysfunction treatment outcomes for temperature-controlled radiofrequency and functional rhinoplasty surgery: a systematic review and meta-analyses

BACKGROUND

Nasal valve dysfunction (NVD) is a substantial contributor to nasal airway obstruction. Minimally-invasive temp-erature-controlled radiofrequency (TCRF) treatment of the nasal valve is available and comparison with surgical techniques is warranted.

METHODOLOGY

Databases: Medline (PubMed), Embase, Cochrane Library.

POPULATION

adults with preprocedural nasal obstruction symptom evaluation (NOSE) score ≥45. Treatment effects were derived from a random effects model and reported as weighted mean difference in NOSE score between baseline; 3, 6, and 12 months postprocedure.

RESULTS

Of 2529 initial articles, 5 studies describing TCRF treatment and 63 studies describing functional rhinoplasty were included. Pooled effect sizes for TCRF treatment and functional rhinoplasty were comparable in all analyses.

CONCLUSIONS

TCRF treatment of the internal nasal valve for NVD was associated with sustained effects comparable to functional rhinoplasty addressing the nasal valve only, rhinoplasty without concomitant turbinate treatment, and all rhinoplasty.

Mepolizumab improves sense of smell in severe chronic rhinosinusitis with nasal polyps: SYNAPSE

BACKGROUND

Loss of smell is one of the most bothersome and difficult-to-treat symptoms in patients with severe chronic rhinosinusitis with nasal polyps (CRSwNP).

METHODOLOGY

SYNAPSE was a 52-week Phase III study of 4-weekly mepolizumab (100 mg subcutaneously) plus standard of care in adults with severe bilateral CRSwNP. This post hoc analysis assessed changes from baseline to study end in loss of smell visual analogue scale (VAS) symptom score, in patients stratified by several baseline clinical characteristics. SinoNasal Outcomes Test (SNOT)-22 sense of smell/taste item and University of Pennsylvania Smell Identification Test (UPSIT) scores were also assessed.

RESULTS

SYNAPSE enrolled 407 patients (mepolizumab=206; placebo=201) with impaired sense of smell at baseline. Improvements from baseline to study end in loss of smell VAS score were greater with mepolizumab versus placebo (treatment difference: −0.37) and most notable in patients with fewer or more recent prior surgeries (treatment difference: 1 vs 2 vs more than 2 prior surgeries,−1.29 vs −0.23 vs −0.07; =3 years since last surgery, −0.89 vs 0.22). Approximately 25% of patients had baseline UPSIT scoresavailable; among those scoring =19 by study end. The SNOT-22 sense of smell/taste item score improved with mepolizumab versus placebo.

CONCLUSIONS

Mepolizumab treatment improved patients' perceived sense of smell, as measured by loss of smell VAS score and SNOT-22 sense of smell/taste item score in patients with severe refractory CRSwNP.

Comparison of nasal valve dysfunction treatment outcomes for temperature-controlled radiofrequency and functional rhinoplasty surgery: a systematic review and meta-analyses

BACKGROUND

Nasal valve dysfunction (NVD) is a substantial contributor to nasal airway obstruction. Minimally-invasive temp-erature-controlled radiofrequency (TCRF) treatment of the nasal valve is available and comparison with surgical techniques is warranted.

METHODOLOGY

Databases: Medline (PubMed), Embase, Cochrane Library.

POPULATION

adults with preprocedural nasal obstruction symptom evaluation (NOSE) score ≥45. Treatment effects were derived from a random effects model and reported as weighted mean difference in NOSE score between baseline; 3, 6, and 12 months postprocedure.

RESULTS

Of 2529 initial articles, 5 studies describing TCRF treatment and 63 studies describing functional rhinoplasty were included. Pooled effect sizes for TCRF treatment and functional rhinoplasty were comparable in all analyses.

CONCLUSIONS

TCRF treatment of the internal nasal valve for NVD was associated with sustained effects comparable to functional rhinoplasty addressing the nasal valve only, rhinoplasty without concomitant turbinate treatment, and all rhinoplasty.

Probing strongly exchange coupled magnetic behaviors in soft/hard Ni/CoFe2O4 core/shell nanoparticles

Exchange coupling in a model core-shell system is demonstrated as a step on the path to 3d exchange spring magnets. Employing a model system of Ni@CoFe2O4, high quality core-shell nanoparticles were fabricated using a simple two-step method. The microstructural quality was validated using TEM, confirming a well-defined interface between the core and the shell. A strongly temperature dependent two-phase magnetic hysteresis loop was measured, wherein an analysis of step heights indicates coupling of roughly 50% between the core and the shell. Element-specific XMCD hysteresis confirms the presence of exchange coupling, suppressing the superparamagnetism of the Ni core at room temperature, and reaching a coercivity of >6 kOe at 80 K. These results provide a pathway to the development of heterostructured metal-oxide exchange coupled nanoparticles with improved maximum energy product.

EUFOREA summit in Brussels 2023: inspiring the future of allergy & respiratory care

In March 2023, the European Forum for Research and Education in Allergy and Airways diseases (EUFOREA) organized its bi-annual Summit in Brussels with expert panel members of EUFOREA, representatives of the EUFOREA patient advisory board, and the EUFOREA board and management teams. Its aim was to define the research, educational and advocacy initiatives to be developed by EUFOREA over the next 2 years until the 10th anniversary in 2025. EUFOREA is an international non-for-profit organization forming an alliance of all stakeholders dedicated to reducing the prevalence and burden of chronic allergic and respiratory diseases via research, education, and advocacy. Based on its medical scientific core competency, EUFOREA offers an evidence-supported platform to introduce innovation and education in healthcare leading to optimal patient care, bridging the gap between latest scientific evidence and daily practice. Aligned with the mission of improving health care, the expert panels of asthma, allergic rhinitis (AR), chronic rhinosinusitis (CRS) & European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS), allergen immunotherapy (AIT) and paediatrics have proposed and elaborated a variety of activities that correspond to major unmet needs in the allergy and respiratory field. The current report provides a concise overview of the achievements, ambitions, and action plan of EUFOREA for the future, allowing all stakeholders in the allergy and respiratory field to be up-dated and inspired to join forces in Europe and beyond.

EPOS/EUFOREA update on indication and evaluation of Biologics in Chronic Rhinosinusitis with Nasal Polyps 2023

Severe chronic rhinosinusitis with nasal polyps (CRSwNP) is a debilitating disease with a significant impact on the quality of life (QoL). It is typically characterized by a type 2 inflammatory reaction and by comorbidities such as asthma, allergies and NSAID-Exacerbated Respiratory Disease (N-ERD). Here, the European Forum for Research and Education in Allergy and Airway diseases discusses practical guidelines for patients on biologic treatment. Criteria for the selection of patients who would benefit from biologics were updated. Guidelines are proposed concerning the monitoring of the drug effects that provide recognition of responders to the therapy and, subsequently, the decision about continuation, switching or discontinuation of a biologic. Furthermore, gaps in the current knowledge and unmet needs were discussed.

The EUFOREA pocket guide for chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is known to affect around 5 % of the total population, with major impact on the quality of life of those severely affected (1). Despite a substantial burden on individuals, society and health economies, CRS often remains underdiagnosed, under-estimated and under-treated (2). International guidelines like the European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS) (3) and the International Consensus statement on Allergy and Rhinology: Rhinosinusitis 2021 (ICAR) (4) offer physicians insight into the recommended treatment options for CRS, with an overview of effective strategies and guidance of diagnosis and care throughout the disease journey of CRS.

Evaluating treatment response to mepolizumab in patients with severe CRSwNP

BACKGROUND

The SYNAPSE study (NCT03085797) demonstrated that mepolizumab decreased nasal polyp (NP) size and nasal obstruction in patients with chronic rhinosinusitis with NP (CRSwNP).

METHODS

SYNAPSE, a randomized, double-blind study, included patients with recurrent, refractory, severe CRSwNP, eligible for repeated surgery despite receiving standard of care (SoC). Patients received 4-weekly mepolizumab 100 mg or placebo subcutaneously plus SoC for 52 weeks. This post hoc analysis further characterized treatment responses and association with patient characteristics. The proportion of patients meeting any and each of five response criteria indicating improvement in disease-specific quality of life, NP size, nasal obstruction, loss of smell, and overall symptoms at Weeks 24 and 52, were assessed in subgroups: 1) no surgery; 2) neither surgery nor systemic corticosteroids (SCS).

RESULTS

Of 407 patients in the intention-to-treat population, 381 and 343 patients had no sinus surgery by Weeks 24 and 52, respectively. More mepolizumab- versus placebo-treated patients without surgery by Weeks 24 and 52 met each response criteria. Of the mepolizumab-treated patients without surgery by Week 24, 109 (55%) responded across ≥ 3 criteria, increasing to 126 (67%) by Week 52. Similar response trends were seen for patients with neither surgery nor SCS by Weeks 24 and 52. At either timepoint, there were no major differences in baseline characteristics between mepolizumab-treated full- (5/5 categories) and non-responders (0/5 categories).

CONCLUSIONS

Most patients who completed SYNAPSE required neither surgery nor SCS use and in addition achieved a progressive and sustained clinical response to mepolizumab underscoring the therapeutic benefits of mepolizumab in severe CRSwNP.

Prasugrel-based de-escalation vs. conventional therapy after percutaneous coronary intervention in ACS patients according to the renal function

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): A consortium of six companies in Korea (Daiichi Sankyo, Boston Scientific, Terumo, Biotronik, Qualitech Korea, and Dio).

Background

Patients with coronary artery disease and impaired renal function are at higher risk for both bleeding and ischemic adverse events after percutaneous coronary intervention (PCI).

Purpose

We assessed the efficacy and safety of a prasugrel based de-escalation strategy in patients with impaired renal function.

Methods

We conducted a post-hoc analysis of the HOST-REDUCE-POLYTECH-ACS study. Patients with available estimated glomerular filtration rate (eGFR) (n=2,311) were categorized into three groups. (high eGFR: ≥90 mL/min; intermediate eGFR: ≥60 and <90 mL/min; low eGFR: <60 mL/min). The endpoints were bleeding outcomes (Bleeding Academic Research Consortium type 2, or higher), ischemic outcomes (cardiovascular death, myocardial infarction, stent thrombosis, repeat revascularization, and ischemic stroke), and net adverse clinical events (all cause death, BARC 2 or greater bleeding, MI, stent thrombosis, repeat revascularization, and ischemic stroke) at 1 year follow-up. The hazard ratio (HR) and 95% Confidence interval (CI) were calculated from the multivariate Cox proportional hazard regression analysis. Covariates that were considered clinically meaningful were included. The probability risk ratio was obtained by dividing ischemic hazard function from the bleeding hazard function.

Results

With respect to net adverse clinical events, prasugrel de-escalation was beneficial regardless of baseline renal function (p for interaction = 0.508). The relative reduction in bleeding risk from prasugrel de-escalation was higher in the low eGFR group compared with that from both the intermediate and high eGFR groups (relative reduction: 64% [HR 0.36, 95% CI 0.15–0.83] vs. 50% [HR 0.50, 95% CI 0.28-0.90] and 52% [HR 0.48, 95% CI 0.21-1.13] for low, intermediate, and high eGFR groups, p for interaction=0.646). Ischemic risk from prasgurel de-escalation was not significant in all eGFR groups ([HR 1.18, 95% CI 0.47-2.98], [HR 0.95, 95% CI 0.53-1.69], and [HR 0.61, 95% CI 0.26-1.39)], respectively, p for interaction=0.119). The probability risk ratio was highest in low eGFR group (1.06 vs. 1.26 vs. 1.36, for high, intermediate, and low eGFR groups, respectively, p for trend<0.001), suggesting higher relative bleeding risk above ischemic risk. Within those randomized to the de-escalation strategy, the mean probability risk ratio was not significantly different according to renal function (0.89, vs. 0.84 vs. 0.80 respectively, p for trend = 0.053), which was in contrast to those randomized to the conventional strategy where the mean probability risk ratio increased significantly as renal function decreased (1.24 vs. 1.67 vs. 1.94 respectively, p for trend<0.001).

Conclusion

The beneficial effect of prasugrel-based de-escalation strategy was consistent regardless of the baseline renal function, which was mostly driven by a reduction in bleeding risk which was greatest in those with low eGFR.

[Analysis of current status and influencing factors of inflammatory factors among electrical workers in Hainan province]

Objective: To analyze the level and influence factors of inflammatory factors among electrical workers in Hainan Province. Methods: A total of 509 electrical workers were selected as the research subjects with random cluster sampling in September 2020. Basic information was collected by questionnaire, the serum IL-6, IL-8 and TNF-α levels of the subjects were detected by Luminex.Mann-Whitney U test and Kruskal-wallis H test were used for univariate analysis. Ordinal logistic regression analysis was used for potential influencing factors of the level of inflammatory factors. Results: The median concentrations of IL-6, IL-8 and TNF-α in serum were 2.78, 9.77 and 8.18 pg/ml. Compared with women, male was a risk factor for the increase of IL-6 levels (OR=1.80, 95%CI: 1.08~3.00, P=0.024) . Compared with 51-60 years old, 21-31 years old (OR=0.27, 95%CI: 0.18~0.42, P<0.001) , 31-41 years old (OR=0.27, 95%CI: 0.17~0.43, P<0.001) and 41-51 years old (OR=0.64, 95%CI: 0.41~0.99, P=0.043) were protective factors for the increase of IL-8 level. Compared with day shift workers, shift work was a risk factor for the increase of IL-8 level (OR=1.73, 95%CI: 1.21~2.48, P=0.003) . Compared with women, male was a risk factor for the increase of TNF-α levels (OR=2.87, 95%CI: 1.70~4.86, P<0.001) . Compared with workers who exposed to 7 or more occupational hazard factors, exposed to 1~3 (OR=0.53, 95%CI: 0.30~0.92, P=0.024) occupational hazard factors were protective factors for the increase of TNF-α levels. Conclusion: The level of inflammatory factors was related to sex, age, work system and occupational environment, which can provide basic data for follow-up research on occupational population.

Aspirin vs. Clopidogrel as a Chronic maintenance monotherapy after PCI in patients with high ischemic risk and high bleeding risk: Subgroup analysis of the HOST-EXAM trial

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

on behalf of the HOST-EXAM investigators

Background

The HOST-EXAM randomized clinical trial recently performed a comparison of clopidogrel monotherapy vs. aspirin monotherapy in patients requiring indefinite antiplatelet monotherapy after percutaneous coronary intervention (PCI). This study randomized 5,438 patients who maintained dual antiplatelet therapy without clinical events for 6–18 months after PCI with drug-eluting stents (DES) to receive a monotherapy agent of clopidogrel 75 mg once daily or aspirin 100 mg once daily for 24 months. During the 24-month follow-up, the primary outcome (a composite of all-cause death, non-fatal myocardial infarction, stroke, readmission due to acute coronary syndrome, and Bleeding Academic Research Consortium (BARC) bleeding type 3 or greater) rate was significantly lower in the clopidogrel group (hazard ratio [HR] 0.73 [95% CI 0.59–0.90]; p = 0.0035). However, it is uncertain whether the beneficial effect of clopidogrel will be consistent in patients with high ischemic risk or those with high bleeding risk.

Methods

This is a post-hoc analysis of the HOST-EXAM trial. A high ischemic risk was defined as those who had at least 1 of the following procedural features: 3 vessels treated, ≥3 stents implanted, ≥3 lesions treated, bifurcation PCI, total stent length &gt;60 mm, or left main PCI. Patients with high bleeding risk were defined according to the Academic Research Consortium for High Bleeding Risk (ARC-HBR) criteria. The co-primary outcome were thrombotic endpoints (a composite of cardiac death, non-fatal myocardial infarction, ischemic stroke, readmission due to acute coronary syndrome, and definite or probable stent thrombosis) and bleeding endpoints (BARC type ≥2 bleeding events) at 24-month follow-up.

Results

 Among the total population, 22.1% had high ischemic risk and 21.4% had high bleeding risk. Complex PCI was not associated with a higher risk of thrombotic endpoints, nor bleeding endpoints. For patients with a high bleeding risk, these patients had a higher risk of both thrombotic endpoints (HR 1.545, 95% CI 0.141-2.092, p = 0.005) and bleeding endpoints (HR 3.418, 95% CI 2.413-4.840, p &lt; 0.001). The primary results focusing on the interaction between high ischemic risk, high bleeding and the antiplatelet regimen will be presented.

Conclusion

The current post-hoc analysis of the HOST-EXAM trial will evaluate the efficacy of clopidogrel monotherapy vs. aspirin monotherapy during the chronic maintenance period after PCI, in patients with high ischemic risk or those with high bleeding risk.

A novel index reflecting both anatomical and physiologic parameters in coronary artery disease, the FFR adjusted SYNTAX score (FaSs)

Background

Various physiology-based indices have been proposed to predict adverse clinical events in patients with coronary artery disease (CAD), such as the sum of three vessel-fractional flow reserve (3v-FFR), and the functional SYNTAX score (fSS). However, these values could not fully reflect the anatomical factors, which remains as a barrier for clinical application of these indices.

Purpose

To propose a novel index which can reflect both anatomical and physiologic features in CAD patients, and evaluate the additional predictive value for cardiovascular adverse events compared to previous indices.

Methods

For an index which can reflect both anatomical and physiologic features, we proposed the FFR adjusted SYNTAX score (FaSs). The FaSs is calculated by adding the product of the SYNTAX score and `1-FFR', for all three major coronary arteries. Among the 1136 patients who enrolled at 3V FFR-FRIENDS study, we investigated 866 patients, after excluding those who had missing variables. The 3v-FFR, fSS and FaSs were calculated, derived from the baseline FFR and SYNTAX score. Patients were divided into two groups according to the median value of each index. The primary endpoint was major adverse cardiac events (MACE, a composite of cardiac death, myocardial infarction and ischemia-driven revascularization) at 2 years follow-up.

Results

Among the total population, MACE occurred in 35 (4.04%) patients. Using the median value in a multivariable COX regression model, only FaSs was associated with an increased risk of MACE, (Hazard Ratio [HR] 5.256, 95% confidence interval [CI] 2.014–13.720), while 3v-FFR (HR 1.383, 95% CI 0.685–2.790) and fSS (HR 1.640, 95% CI 0.830–3.243) were not significantly associated with a higher risk of MACE. This was also observed in the Kaplan Meier survival curve analysis (log-rank p value: p&lt;0.001 for FaSs, 0.153 for 3v-FFR, and 0.061 for fSS; Figure 1) The sensitivity and specificity of the FaSs was 85.7% and 51.6%, which was higher compared to the 3v-FFR (62.9% and 49.3%, respectively) and fSS (57.1% and 58.5%, respectively). When these indices were combined with clinical risk factors (age, sex, hypertension, diabetes, hyperlipidemia, chronic renal failure, LVEF&lt;40%), FaSs was superior compared with 3v-FFR and fSS assessed in regards of the predictive accuracy for MACE (Figure 2).

Conclusion

The FaSs, which is a novel index calculated by a formula using the SYNTAX score and FFR, showed a superior predictive value for MACE compared to previous indices. Our results confirm the importance of considering both anatomical and physiologic parameters in evaluating the patient's risk for cardiovascular adverse outcomes.

Funding Acknowledgement

Type of funding sources: None.

Dupilumab reduces systemic corticosteroid use and sinonasal surgery rate in CRSwNP

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a type 2 inflammatory disease with a high symptom burden and poor quality of life. Treatment options include recurrent surgeries and/or frequent systemic corticosteroids (SCS). Dupilumab, a fully human monoclonal antibody, blocks the shared receptor component for interleukin-4 and interleukin-13, key drivers of type 2-mediated inflammation. We report results of pooled analyses from 2 randomised, double-blind, placebo-controlled phase 3 studies (SINUS 24 [NCT02912468]; SINUS-52 [NCT02898454]) to evaluate dupilumab effect versus placebo in adults with CRSwNP with/without SCS use and sinonasal surgery.

METHODOLOGY

SINUS-24 patients were randomised 1:1 to subcutaneous dupilumab 300 mg (n=143) or placebo (n=133) every 2 weeks (q2w) for 24 weeks. SINUS-52 patients were randomised 1:1:1 to 52 weeks of subcutaneous dupilumab 300 mg q2w (n=150), 24 weeks q2w followed by 28 weeks of dupilumab 300 mg every 4 weeks (n=145) or 52 weeks of placebo q2w (n=153).

RESULTS

Dupilumab reduced the number of patients undergoing sinonasal surgery (82.6%), the need for in-study SCS use (73.9%), and SCS courses (75.3%). Significant improvements were observed with dupilumab vs placebo regardless of prior sinonasal surgery or SCS use in nasal polyp, nasal congestion, Lund-MacKay, and Sinonasal Outcome Test (22-items) scores, and the University of Pennsylvania Smell Identification Test.

CONCLUSIONS

Dupilumab demonstrated significant improvements in disease signs and symptoms and reduced the need for sino-nasal surgery and SCS use versus placebo in patients with severe CRSwNP, regardless of SCS use in the previous 2 years, or prior sinonasal surgery.

Hematogeneous Pulmonary Metastasis

The purpose of this study was to develop an experimental model of pulmonary metastases using VX-2 tumor, and to describe sequential radiologic and pathologic findings with special attention to the interstitial changes around the metastatic nodules. Through ear veins of 25 rabbits, VX-2 tumor cell suspension was injected with 0.8-mm scalp needles. Chest radiographs were taken every other day after tumor injection. The rabbits were sacrificed at scheduled times from 3 to 30 days after tumor injection. The inflated and fixed lungs were examined with visual inspection, low-kV radiography, high resolution CT (HRCT), microradiography of the sliced lung and with histopathologic studies. Hematogeneous pulmonary metastases occurred in 24 of 25 rabbits. In addition to the metastatic nodules, perinodular and peribronchovascular infiltrations were seen on low-kV radiography, HRCT, microradiography and histologic studies.

Primary Angiosarcoma of the Spleen

The CT and MR findings in 2 patients with surgically proven splenic angiosarcoma are presented. Two distinctive radiologic and pathologic patterns were observed: total tumor replacement of the spleen with preservation of normal contour or multiple nodular masses in the spleen. The various findings on CT and MR imaging reflected the hemorrhagic nature of the lesions with increased iron content. MR imaging appeared to be superior to CT in demonstrating these features. In the case of focal lesions, radiologic differentiation from lymphoma or metastasis was impossible.

Switching bipolar hepatic radiofrequency ablation using internally cooled wet electrodes: comparison with consecutive monopolar and switching monopolar modes

OBJECTIVE

To evaluate whether switching bipolar radiofrequency ablation (SB-RFA) using three internally cooled wet (ICW) electrodes can induce coagulations >5 cm in porcine livers with better efficiency than consecutive monopolar (CM) or switching monopolar (SM) modes.

METHODS

A total of 60 coagulations were made in 15 in vivo porcine livers using three 17-gauge ICW electrodes and a multichannel radiofrequency (RF) generator. RF energy (approximately 200 W) was applied in CM mode (Group A, n = 20) for 24 min, SM mode for 12 min (Group B, n = 20) or switching bipolar (SB) mode for 12 min (Group C, n = 20) in in vivo porcine livers. Thereafter, the delivered RFA energy, as well as the shape and dimension of coagulations were compared among the groups.

RESULTS

Spherical- or oval-shaped ablations were created in 30% (6/20), 85% (17/20) and 90% (18/20) of coagulations in the CM, SM and SB groups, respectively (p = 0.003). SB-RFA created ablations >5 cm in minimum diameter (Dmin) in 65% (13/20) of porcine livers, whereas SM- or CM-RFA created ablations >5 cm in only 25% (5/20) and 20% (4/20) of porcine livers, respectively (p = 0.03). The mean Dmin of coagulations was significantly larger in Group C than in Groups A and B (5.1 ± 0.9, 3.9 ± 1.2 and 4.4 ± 1.0 cm, respectively, p = 0.002) at a lower delivered RF energy level (76.8 ± 14.3, 120.9 ± 24.5 and 114.2 ± 18.3 kJ, respectively, p < 0.001).

CONCLUSION

SB-RFA using three ICW electrodes can create coagulations >5 cm in diameter with better efficiency than do SM- or CM-RFA.

ADVANCES IN KNOWLEDGE

SB-RFA can create large, regular ablation zones with better time-energy efficiency than do CM- or SM-RFA.

Dual-source, dual-energy multidetector CT for the evaluation of pancreatic tumours

OBJECTIVE

To investigate the potential diagnostic value of dual-energy CT (DECT) with virtual non-enhanced (VNE) and iodine-only images, and to determine the optimal mixed ratio of blended images for evaluation of pancreatic diseases.

METHODS

Multiphasic DECT was performed in 44 patients with focal pancreatic disease. DECT was used during the pancreatic and hepatic venous phases, and a peak kilovoltage of 120 kVp was used for both non-contrast phases. For qualitative analysis of the CT images, two radiologists assessed three image sets (VNE, iodine-only and blended images) in order to determine the acceptability of VNE in replacing true non-enhanced (TNE) images, the added value of iodine-only images and the preferred blending ratio. For quantitative analyses, the CT numbers and image noise of the pancreatic parenchyma, lesions, aorta and psoas muscle were measured. The contrast-to-noise ratio of the lesion was calculated on the pancreatic phase images. The effective radiation dose for DECT and TNE images was calculated. Statistical comparisons were made using the Friedman test, the Wilcoxon test, the paired t-test and repeated measures of analysis of variation with Bonferroni correction for multiple comparisons.

RESULTS

The level of acceptance of the VNE images in replacing TNE images was 90.9%. Regarding the iodine-only images, 50% of the cases were found to have an added value. The linear-blended images with a weighting factor of 0.5 were preferred.

CONCLUSIONS

DECT was able to provide high-quality VNE images that could replace TNE images and iodine-only images showing an added value. Blended images with a weighting factor of 0.5 were preferred by the reviewers.

Enhancement patterns of hepatocellular carcinomas on multiphasicmultidetector row CT: comparison with pathological differentiation

OBJECTIVE

The objective of this study was to determine the incidence of typical and atypical enhancement patterns of hepatocellular carcinomas (HCCs) on multiphasic multidetector row CT (MDCT) and to correlate the enhancement patterns and morphological image findings of HCC with the degree of tumour differentiation.

METHODS

MDCT images of 217 patients with 243 surgically proven HCCs were evaluated through consensus reading by two radiologists. Our MDCT protocol was composed of precontrast, arterial, portal and delayed phases. The reviewers analysed the CT images for degree of attenuation; relative timing of washout; presence of dysmorphic intratumoral vessels, aneurysms and necrosis; tumour size; tumour margin; presence of pseudocapsule; intratumoral heterogeneity; and determined enhancement pattern. The imaging features were correlated with tumour differentiation using Fisher's exact test or the χ(2) test.

RESULTS

Among 243 HCCs, 137 (56.4%) showed the typical enhancement pattern of HCC, which is arterial enhancement and washout on portal or equilibrium phase images. In the arterial phase, 190 of 243 (78.2%) HCCs showed hypervascularity, with approximately three quarters of poorly differentiated (PD) (34 of 45, 75.6%) and moderately differentiated (MD) HCCs (92 of 123, 74.8%) showing washout during the portal or delayed phases, vs only 50% of well-differentiated (WD) HCCs (11 of 22; p<0.048). The presence of intratumoral vessels and aneurysms, tumour necrosis, attenuation of precontrast, the relative timing of washout, intratumoral attenuation heterogeneity, tumour margin and tumour size were correlated with the pathological differentiation of HCCs (p<0.05).

CONCLUSION

A typical enhancement of HCCs on MDCT was not unusual (43.6%) and WD and PD HCCs account for most of the atypical enhancement patterns. Early washout favoured MD and PD HCCs rather than WD HCCs, whereas in our study the presence of intratumoral aneurysm was a highly specific finding for PD HCC.

Multiple-electrode radiofrequency ablations using Octopus® electrodes in an in vivo porcine liver model

OBJECTIVES

The objective of this study was to determine the in vivo efficacy of radiofrequency ablation (RFA) in porcine liver using Octopus® electrodes for creating a large coagulation compared with RFA using clustered electrodes.

METHODS

A total of 39 coagulations were created using a 200-W generator and clustered electrodes or Octopus electrodes during laparotomy in 19 pigs. Radiofrequency was applied to the livers using four protocols: (1) Group A-1, monopolar mode using a clustered electrode (n=11); (2) Group A-2, monopolar mode using an Octopus electrode (n=11); (3) Group B-1, consecutive monopolar mode using three, clustered electrodes (n=8); and (4) Group B-2, switching monopolar mode using two Octopus electrodes (n=9). The energy efficiency, shape, diameters (D) and volume (V) of the coagulation volume were compared in each of the two groups.

RESULTS

The mean maximum D and V of the coagulations in Group A-2 (4.7 cm and 33.1 cm(3), respectively) were significantly larger than those in Group A-1 (4.1 cm and 20.3 cm(3), respectively) (p<0.05). Furthermore, the mean minimum D, maximum D and V of the coagulations in Group B-2 were significantly larger than those in Group B-1, i.e. 5.3 vs 4.0 cm, 6.6 vs 4.9 cm and 66.9 vs 30.2 cm(3), respectively (p<0.05). The energy efficiencies were also significantly higher in Groups A-2 and B-2 than in Groups A-1 and B-1 (p<0.05).

CONCLUSION

The Octopus electrodes were more efficient for creating a large ablation zone than clustered electrodes, and the efficacy of RFA with Octopus electrodes can be amplified in the switching monopolar mode.

Radiofrequency ablation in pig lungs: in vivo comparison of internally cooled, perfusion and multitined expandable electrodes

The purpose of this study was to compare the amounts of in vivo coagulation obtained by radiofrequency (RF) ablation in porcine lung, using three types of electrodes. 15 in vivo ablation procedures were performed in the lungs of five pigs using three kinds of currently available RF devices under CT guidance. After placing an electrode in the lung, three ablation zones were created at each of three different regimens: Group A: RF ablation with an internally cooled electrode; Group B: RF ablation with a perfusion electrode, with instillation of 0.9% NaCl solution at a rate of 1.5 ml min(-1); Group C: RF ablation with a multitined expandable electrode. According to the manufacturer's recommendations, RF application times were 12 min in group A and 20 min in group B. In group C, RF energy was delivered for 7 min after a mean temperature of 110 degrees C was reached at 5 cm deployment. 36 min after the procedures, contrast-enhanced CT scans were obtained to evaluate the volume of zone of coagulation, and lungs were harvested for gross measurements. After macroscopic and histopathological analyses of 5 mm-thick lung sections, diameters, volumes and variation coefficients of regions of central coagulation were assessed. During RF ablation, the perfusion electrode allowed a larger energy delivery than the internally cooled or the multitined expandable electrodes, i.e. 33.6+/-4.7 kJ in group A, 40.0+/-8.2 kJ in group B and 23.5+/-6.1 kJ in group C (p<0.05). On gross observation, the cut surface of the gross specimen containing RF-induced coagulation showed that the ablated tissue appeared to be a central, firm, dark-brown area surrounded by an irregular outer margin (approximately 3-10 mm thick) of bright red tissue. In vivo studies showed that RF ablation using the perfusion electrode achieved larger coagulation volume than RF ablation using the other electrodes (p<0.05): 7.2+/-4.1 cm3 in group A; 16.9+/-5.5 cm3 in group B; 7.5+/-3.3 cm3 in group C. The corresponding variation coefficients were 0.55, 0.31, and 0.45, respectively. Our study shows that RF ablation using a perfusion electrode achieves a larger coagulation volume with an irregular margin than RF ablation using internally cooled or multitined expandable electrodes in the porcine lung.

CT colonography in a Korean population with a high residue diet: Comparison between wet and dry preparations

AIM

To compare wet and dry preparation methods for computed tomography colonography (CTC) in terms of preparation quality, interpretation time, and diagnostic performance for polyp detection in a population with a high residue diet.

MATERIALS AND METHODS

Eighty-six patients were divided into two groups. Group 1 (n=24) received a wet preparation of 4l polyethylene glycol (PEG) solution, and group 2 (n=62) received a dry preparation of phosphor-soda. Abnormal findings, including polyps, and the time required to interpret the CTC images in both groups were documented by a radiologist. CTC findings were compared to those of colonoscopy as a reference standard. Two radiologists evaluated the quality of CTC with regard to residual fluid, faeces, and colonic distension using a four-point scale in consensus. Statistical differences for residual fluid, faeces, distensibility on CTC, and interpretation time between the two groups were analysed. The diagnostic performance of CTC in both groups was also compared.

RESULTS

One-hundred and ninety polyps in 70 patients were identified using colonoscopy. Regarding the quality of images produced the wet preparation was significantly better than the dry preparation (p<0.05). The average interpretation time was significantly shorter for the wet group (11.7 min) than the dry group (16.4 min) (p<0.05). For per-patient analysis, the positive predictive value (PPV) was significantly better for the wet (100%) than the dry group (79.6%; p=0.025). Sensitivities and PPV for >or=10 mm polyps were comparable between two groups (p>0.05).

CONCLUSION

In a population with a high-residue diet, CTC with wet preparation can be interpreted in a time-efficient manner and is comparable with CTC with dry preparation.

Abdominal cavernous Iymphangiomas: CT findings

Two adult patients with histopathologically proved cavernous lymphangiomas and one adult patient with lymphangiomas of strongly presumed cavernous type by cytologic and computed tomographic findings are reported. On computed tomograms, multiple, aggregated, small, and tiny cysts without a solid portion, along the lymphatic channels are characteristic computed tomographic findings for cavernous lymphangiomas.

An ex-vivo experimental study on optimization of bipolar radiofrequency liver ablation using perfusion-cooled electrodes

PURPOSE

To determine optimal parameters for bipolar radiofrequency ablation (RFA) using perfusion-cooled electrodes to create a large ablation volume in ex vivo bovine liver.

MATERIAL AND METHODS

Three sets of RF experiments were performed using a 200-Watt generator and two 15-gauge perfusion-cooled or internally cooled electrodes in ex vivo bovine livers. In the first set of experiments, to find the ideal inter-electrode distance for creating large coagulation necrosis, 30 ablation lesions were created by bipolar RFAs at inter-electrode spacings of 3 cm, 4 cm, and 5 cm. In the second set of experiments, to explore the ideal duration of RF application, bipolar RFAs were performed for 10 min and 20 min. In the first and second experiments, 10 lesions were made for each condition with infusion of 6% hypertonic saline (HS) at 2 ml/min. In the third set of experiments, 10 ablation lesions were created by bipolar RFAs using internally cooled electrodes without HS infusion. The mean volume of those ablation lesions was then compared to that of the lesions created by bipolar RFA using perfusion-cooled electrodes in the second experiments. Tissue impedance, dimension, and shape of the ablated areas were compared in each condition.

RESULTS

In the first set of experiments, bipolar RFA created a homogeneous oval or spherical-shaped ablation area between the electrodes at 3-5 cm spacing, but showed a more spherical-shaped lesion at 3 cm inter-electrode spacing than at 4 cm and 5 cm spacing. In the second set of experiments, RF energy delivered for 20 min created a larger dimension of coagulation necrosis than energy delivered for 10 min: 107.6 +/- 34 cm3 versus 59.5 +/- 27 cm3 (P<0.05). In addition, the mean volume of ablation regions obtained with bipolar RFA using the internally cooled electrode was 47.5+/- 17 cm3, which was significantly less than that with bipolar RFA using perfusion-cooled electrodes (P <0.05).

CONCLUSION

Bipolar RFA using perfusion-cooled electrodes achieves homogeneous areas of coagulation necrosis between two electrodes, preferably at 3 or 4 cm inter-electrode distance for 20 min, and is better in creating large coagulation necrosis than bipolar RFA using internally cooled electrodes.

Small gastrointestinal stromal tumours with focal areas of low attenuation on CT: pathological correlation

AIM

To describe the pathology of focal areas of low attenuation in small gastrointestinal stromal tumours on contrast-enhanced computed tomography (CT), and to investigate the association of these areas as predictors of malignant potential.

MATERIALS AND METHODS

Contrast-enhanced helical CT images were obtained of 39 small (up to 5 cm) gastrointestinal stromal tumours. Focal areas of low attenuation were retrospectively evaluated and correlated with histopathological findings. The relation between the mitotic rate of and the presence of focal areas of low attenuation in the tumours was analyzed using Fisher's exact test.

RESULTS

Of the 39 small gastrointestinal stromal tumours, 15 contained focal areas of low attenuation on CT. These were found to be due to solid tumour (n=5), haemorrhage (n=3), haemorrhage with necrosis (n=2), cystic degeneration (n=2), fluid in ulcer (n=2), and fibrous septum (n=1); they were not found to be associated with a high mitotic rate (p=0.45).

CONCLUSION

Focal areas of low attenuation on CT in small gastrointestinal stromal tumours represent varying pathological conditions and do not predict malignant potential.

Calcified Klatskin tumor mimicking intrahepatic stone: case report

Calcification is a relatively uncommon manifestation of malignant liver neoplasm. Calcifications in peripheral cholangiocarcinomas but not in Klatskin tumor have been reported. We present a rare case of Klatskin tumor that had dystrophic calcification mimicking a intrahepatic stone in a 65-year-old man.

Hepatic bipolar radiofrequency ablation using perfused-cooled electrodes: a comparative study in theex vivobovine liver

The purpose of this paper was to demonstrate the efficacy of the dual probe bipolar radiofrequency (RF) system with the perfused-cooled electrodes inducing coagulation necrosis in the ex vivo bovine liver. The perfused-cooled electrode that allows simultaneous internal cooling and interstitial hypertonic saline perfusion has been developed for RF ablation (RFA). RF was applied to excised bovine liver in a bipolar mode at 150 W using a 200 W generator with two perfused-cooled electrodes for 10 min. After placing the electrodes at 3 cm spacing in the explanted liver, 45 ablation zones were created with three different regimens: Group A, using both intraelectrode cooling and interstitial perfusion; group B, using only the intraelectrode cooling; and group C, using only interstitial perfusion. In groups A and C, RFA was performed with the infusion of 6% hypertonic saline at the rate of 2 ml min(-1). During RFA, we measured the tissue temperature at the midpoint between the two electrodes. The dimensions of the ablation zones and the changes in impedance, currents and liver temperature during RFA were compared in these three groups. The mean tissue impedance during RFA in group A (56.7+/-21.7 Omega) and group C (56.9+/-20.6 Omega) was significantly lower than group B (112+/-19.7 Omega) (p<0.001). The mean current was higher in group A (1765+/-128 mA) than groups B (760+/-321 mA) and C (1298+/-349 mA) (p<0.05). In addition, the shortest vertical diameter of coagulation necrosis was greater in groups A (4.9+/-0.5 cm) and C (4.6+/-0.7 cm) than in group B (3.5+/-0.4 cm) (p<0.05). The temperature at the mid-point between the two probes was higher in group A than other groups: 99 degrees C in group A, 88.9 degrees C in group B, and 94.3 degrees C in group C (p>0.05). The ratios of the diameter of the long-axis to the diameter of the vertical-axis of groups A, B and C were 1.1+/-0.1, 1.2+/-0.1, and 1.1+/-0.2, respectively (p<0.05). Bipolar RFA using intraelectrode cooling and the interstitial saline perfusion simultaneously produced ablation zones significantly larger than the area produced by only one measure.

Real-time compound ultrasonography: pictorial review of technology and the preliminary experience in clinical application of the abdomen

The purposes of this essay are to illustrate the technology overview and theoretical benefits of real-time compound ultrasonography (US) and to present our preliminary clinical experience in the evaluation of normal and diseased abdomens. The application of compounding principles to real-time US and its recent reintroduction into mainstream commercial systems have offered new opportunities for its clinical application to the routine examination of the abdomen. In our early preliminary experience, this technique effectively suppressed many of the US artifacts, better depicted the margin or boundary of the lesion, and increased contrast resolution or lesion conspicuity. Therefore, we believe that real-time compound US is a promising technique that may enhance the diagnostic confidence of the examination in the evaluation of normal and diseased abdomens.

Afferent loop obstruction after gastric cancer surgery: helical CT findings

BACKGROUND

We reviewed the computed tomographic (CT) findings of afferent loop obstruction and assessed the value of helical CT in determining the underlying cause.

METHODS

Helical CT scans of 18 patients (12 men and six women; age range = 35-67, mean age = 50 years) with afferent loop obstruction were reviewed. All patients had gastric cancer. Ten patients had undergone radical subtotal gastrectomy with Billroth II gastrojejunostomy, and eight had undergone total gastrectomy with Roux-en-Y esophagojejunostomy. CT images were analyzed retrospectively, and the presumed cause of obstruction on CT was compared with surgical findings (n = 8) and clinical courses (n = 10).

RESULTS

Local recurrence (n = 15), peritoneal seeding (n = 1), internal hernia (n = 1), and adhesion (n = 1) were the presumed causes of obstruction on CT. In all eight patients who underwent a second operation, the cause of afferent loop obstruction was correctly suggested on CT (local recurrence in six patients and adhesion and internal hernia in one patient). In 10 patients who were not re-explored, the clinical findings or biopsy indicated recurrent tumor as suggested on CT.

CONCLUSION

Recurrent tumors and other potential causes of afferent loop obstruction can be correctly predicted with CT in most cases.

Helical CT of postoperative patients with gastric carcinoma: value in evaluating surgical complications and tumor recurrence

BACKGROUND

We assessed computed tomographic (CT) features of postoperative complications and recurrent tumors in gastric cancer patients who underwent radical surgery.

METHODS

We performed a retrospective study of 397 patients who had undergone radical surgery for the treatment of gastric carcinoma and underwent postoperative CT in our institution over a 2-year period. Patients were assigned to one of two groups: group A consisted of 47 patients who underwent CT for complications in the early postoperative period, and group B consisted of 355 patients who underwent CT for evidence of tumor recurrence during the follow-up period. We classified recurrent tumors into four categories: local recurrence, lymph node metastasis, peritoneal seeding, and remote metastasis.

RESULTS

In group A, localized fluid collections or abscesses in the surgical bed were found in 38 patients (81%) and usually involved the left subphrenic area (74%) or the superior recess of the lesser sac (47%). In group B, recurrent tumors were found in 196 patients (55%). Among these, lymph node metastasis was the most common pattern (52%), followed by peritoneal seeding (44%), local recurrence (40%), and remote metastasis (37%).

CONCLUSION

CT after radical surgery for the treatment of gastric carcinoma frequently shows postoperative complications or tumor recurrence. Familiarity with the common postoperative complications and patterns of the tumor recurrence is a prerequisite to accurate interpretation of CT findings in these patients.

Contrast-enhanced dynamic ultrasonography of the liver: optimization of hepatic arterial phase in normal volunteers

BACKGROUND

To optimize hepatic arterial phase timing in contrast-enhanced dynamic ultrasonography (US) of the liver.

METHODS

Dynamic US was performed by using a microbubble-specific mode in 22 healthy volunteers after bolus injection of SH U 508A. Images were analyzed to determine whether hepatic arterial and portal venous phases could be temporally discriminated. Delay times to contrast enhancement at the hepatic artery (A(ini)) and portal vein (P(ini)) and the delay time until the signals between both vessels became inseparable (A(end)) were determined.

RESULTS

The hepatic arterial and portal venous phases could be temporally discriminated in all subjects. A(ini), P(ini), and A(end) (mean +/- standard deviation) were 11.0 +/- 2.0, 14.8 +/- 3.6, and 22.6 +/- 5.1 s, respectively.

CONCLUSION

In hepatic contrast-enhanced dynamic US, hepatic arterial phase scanning should be commenced earlier than 11 s and terminated after 23 s postinjection.

Abdominal amyloidosis: spectrum of radiological findings

Amyloidosis is a disease characterized by the deposition of fibrillar protein amyloid of beta-structure in organs or tissues. It is usually classified as either a primary disease or secondary to a co-existent condition, such as rheumatoid arthritis, tuberculosis, or neoplasm (particularly multiple myeloma or renal cell carcinoma). Amyloid protein deposition can be seen in a variety of organs though it occurs with higher frequency in the gastrointestinal tract, kidney, and heart. Amyloidosis can have a wide spectrum of manifestations in nearly every abdominal organ. Some of these, for example, multiple cystic submucosal masses of the stomach, amyloidosis of the gallbladder, and dirty soft tissue infiltration of the subcutaneous fat, have not yet been covered in the radiological literature. The combination of various imaging techniques and the identification of characteristic computed tomography (CT) hepatic features may help in the differentiation of amyloidosis from other infiltrative diseases; however, confirmative diagnosis can usually only be achieved by tissue biopsy.

Subphrenic bronchogenic cyst mimicking a juxtahepatic solid lesion

Most bronchogenic cysts occur in the mediastinum. However, they may be found near any organ derived from the embryonic foregut, even in the extrathoracic region. We report a case of subphrenic bronchogenic cyst that was initially confused with a solid lesion because of its unusual location and atypical appearance on ultrasonography, computed tomography, and magnetic resonance imaging.

Focal eosinophilic infiltration in the liver: radiologic findings and clinical course

BACKGROUND

We investigated the radiologic findings and clinical course of focal eosinophilic infiltration in the liver.

METHODS

We retrospectively reviewed computed tomographic (CT) and sonographic scans in 20 patients (18 male, two female; mean age, 50 years) with pathologically or clinically proven focal eosinophilic infiltration in the liver by two experienced radiologists in our institute from August 1995 to June 1999. We also correlated radiologic findings with peripheral eosinophil count. Radiologic and clinical findings during the follow-up (range, 2-49 months; mean, 19.5 months) also were analyzed.

RESULTS

Clinical symptoms and signs included abdominal pain (n = 4), easy fatigability (n = 3), weight loss (n = 1), and peripheral eosinophilia (n = 19). Twelve patients were asymptomatic. On sonographic examinations, all lesions were seen as focal, low echoic nodules. On CT, the lesions appeared isoattenuated or low attenuated in the arterial phase and low attenuated in the portal phase, except one case that showed high attenuation in the arterial phase. The margins of most lesions appeared poorly defined. Lesions were single (n = 9) and multiple: two to five (n = 6), six to 10 (n = 3), and more than 10 (n = 2). Each lesion was smaller than 2 cm; only one was 4 cm in diameter. The distribution of the lesion was subcapsular in 14 patients and central in five. Diffuse dissemination was observed in one. Eosinophil-associated abnormality was not present in other abdominal organ in all cases. The peripheral eosinophil count correlated closely with the number but not with the size of lesions. Sixteen patients who had follow-up images showed complete (n = 14) or partial regression of the lesions with a decrease in size (n = 1) or number (n = 1) after 2-22 months (mean, 6.4 months).

CONCLUSION

Focal eosinophilic infiltration in the liver had somewhat characteristic radiologic findings on sonography and CT. In the correct clinical context of peripheral eosinophilia and self-limited course, these radiologic findings may be helpful in differentiating this condition from other focal hepatic lesions.

Biliary obstruction in metastatic disease: thin-section helical CT findings

BACKGROUND

We describe the thin-section helical computed tomographic (CT) findings of biliary obstruction caused by metastasis.

METHODS

Thin-section helical CT (5 mm slice thickness, 1:1 pitch, portal phase) and direct cholangiography in 50 consecutive patients with biliary obstruction caused by metastases were reviewed retrospectively by three radiologists. The primary sites were the stomach ( n = 36), colon ( n = 12), jejunum ( n = 1), and uterus ( n = 1). The level of biliary obstruction was analyzed with the Bismuth classification, and the CT findings of biliary obstruction were classified into six types: small (<2 cm) periductal masses, large (>/=2 cm) periductal masses, extrinsic compression by a metastatic liver mass, high-attenuation intraductal mass, intrapancreatic mass, and no demonstrable lesion.

RESULTS

The level of biliary obstruction was the hilum in 18 patients (36%), the proximal common duct in 20 (40%), the distal common duct in five (10%), and the periampullary area in seven (14%). Of 18 hilar obstructions, tumor involvement of the secondary confluence of intrahepatic bile ducts was seen in 10 (right in six, left in one, and bilateral in three). Periductal masses were seen in 68% (small in 18, large in 16). In one patient (2%), a large metastatic mass of the liver resulted in extrinsic compression and biliary obstruction. Lesions mimicking primary biliary or pancreatic tumor were seen in four, respectively. In seven, we found no obstructing lesion on CT.

CONCLUSION

Biliary obstruction in patients with known primary malignancies can show atypical patterns mimicking primary pancreatobiliary malignancies on thin-section helical CT.

Acute hepatic vein occlusion: spiral CT findings in an experimental study

BACKGROUND

We investigated spiral computed tomographic (CT) findings and underlying hemodynamic alterations in acute hepatic vein occlusion.

METHODS

In nine dogs, immediately after balloon occlusion of the right ( n = 4) or left ( n = 5) hepatic vein through the transjugular or transfemoral route, we performed single-level dynamic CT with intravenous administration of contrast medium. We created time attenuation curves of individual hepatic segments showing attenuation differences. To investigate underlying hemodynamic alterations, hepatic arteriograms were obtained in two dogs.

RESULTS

In all cases, there were three compartments with different time attenuation curves: normal, occluded, and adjacent. The normal compartment, which comprised segments far from the occluded hepatic compartment, showed the normal pattern of hepatic enhancement. The occluded compartment, which was the drainage territory of the occluded hepatic vein, showed high attenuation in the early arterial phase and low attenuation in the portal phase. The adjacent compartment, which shared the same portal vein with the occluded compartment and was drained by the patent hepatic vein adjacent to the occluded one, showed strong contrast enhancement in the late arterial and early portal phase. Spiral CT and hepatic arteriography demonstrated the arterioportal shunt and reversed portal venous flow in the occluded compartment, which drained into the adjacent compartment.

CONCLUSION

Acute hepatic vein occlusion on spiral CT appears as mild, early arterial, high attenuation and portal low attenuation of the occluded compartment and strong enhancement in the late arterial and early portal phases of the adjacent compartment due to arterioportal shunt and reversed portal flow.

Gastric mucosa-associated lymphoid tissue lymphoma: spectrum of findings at double-contrast gastrointestinal examination with pathologic correlation

Mucosa-associated lymphoid tissue (MALT) is found in the surface epithelium of the stomach. MALT lymphoma is extranodal lymphoma originating from MALT. In the stomach, a strong association with Helicobacter pylori infection has been demonstrated. Low-grade gastric MALT lymphoma has been reported to have variable features at upper gastrointestinal (UGI) examination. Twenty-two patients with low-grade MALT lymphoma had ulcers (n = 11), fold thickening (n = 7), mucosal nodularity (n = 7), masses (n = 6), or prominent areae gastricae (n = 4) at UGI examination. Six patients with high-grade MALT lymphoma had masses (n = 4), fold thickening (n = 3), ulcers (n = 1), or mucosal nodularity (n = 1) at UGI examination. These findings were similar to those in gastric carcinoma or gastritis. Differentiation of low-grade MALT lymphoma from gastritis or gastric carcinoma was more difficult than differentiation of high-grade MALT lymphoma. Lesions of MALT lymphoma associated with H pylori gastritis were diffuse or multiple in 65% of cases; however, lesions of MALT lymphoma without proved H pylori gastritis were focal or solitary in 80% of cases. Therefore, multiplicity of lesions in MALT lymphoma was closely associated with H pylori infection.

Poly(A) binding protein II in Xenopus laevis is expressed in developing brain and pancreas

We have isolated Xenopus homolog of poly(A) binding protein II (XPABPII) and examined its expression during early embryogenesis and embryonic gut development. XpabpII encodes a nuclear protein of 296 amino acids that contains an alpha-helical coiled-coil domain and a ribonucleoprotein-type RNA binding domain. XpabpII is expressed both maternally and zygotically. In gastrula and neurula embryos, XpabpII is expressed mainly in ectoderm, neural and epidermal. From tailbud through to tadpole stages, the neural tissue specific expression of XpabpII gradually becomes confined to the specific vesicle regions of developing brain, being detected in the eye, olfactory pit, telencephalon and mesencephalon, but being excluded from the diencephalon region. Intriguingly, XpabpII transcripts are observed in differentiating gut endoderm. XpabpII first becomes visible in the anterior part of a stage 35 embryonic gut in which prospective liver, stomach and pancreas are located. During further development, uniform expression in anterior gut gradually becomes restricted to the pancreas rudiment. At the seventh day of development, when the gut has formed a complex coiled structure in which each organ contains clearly differentiated cell type, XpabpII is detectable exclusively in the pancreas. Taken together, we suggest that XpabpII plays a specific role in the polyadenylation process of genes involved in brain and pancreas development.

Comparison of contrast-enhanced fundamental imaging, second-harmonic imaging, and pulse-inversion harmonic imaging

RATIONALE AND OBJECTIVES

To investigate the feasibility of recent contrast-specific ultrasound techniques in depicting vascular flow and the effects of changing the output power of the transducer and insonation mode on contrast enhancement, the authors performed an experimental study with a flow phantom.

METHODS

While changing the mechanical index and the sound insonation mode (continuous and intermittent), images were obtained with three contrast-enhanced ultrasound techniques: fundamental, second-harmonic, and pulse-inversion harmonic imaging (PIHI) after a bolus injection of microbubble contrast agent. The images were compared on a time-intensity curve.

RESULTS

In assessing fixed flow (10 cm/s), PIHI showed the best depiction of flow signal. In intermittent scanning, increases in the mechanical index caused stronger flow signals and longer enhancement duration in all techniques. However, continuous scanning revealed poor depiction of flow signal regardless of the technique or changes in the mechanical index because of significant bubble destruction.

CONCLUSIONS

Microbubble-enhanced PIHI with intermittent scanning at a high mechanical index can depict vascular flow highly effectively without shortening the duration of enhancement.

A novel Xenopus acetyltransferase with a dynamic expression in early development

We have isolated a novel acetyltransferase from Xenopus laevis, named Xat-1. Xat-1 cDNA encodes a predicted protein of 846 amino acids that contains tetratricopeptide repeat (TPR) domains mediating protein-protein interactions and a bipartite nuclear localization signal (NLS). Its apparent molecular mass of 98.8 kDa was determined by SDS-PAGE analysis of Xat-1 recombinant protein in vitro translated in rabbit reticulocyte lysate. Xat-1 is homologous to N-terminal acetyltransferase 1 (NAT1), a gene that was originally discovered in yeast. Furthermore, it has many orthologs from human, mouse, Drosophila, C. elegans, and even Arabidopsis, thereby suggesting that these constitute a novel acetyltransferase family whose functions have been not examined. Xat-1 transcripts are expressed at relatively constant levels throughout early embryonic stages. They also exhibit dynamic expression pattern in brain, somites, branchial arches, pronephros, and otic vesicles.

An evolution in the management of sinonasal inverting papilloma

OBJECTIVE

We reviewed the 15-year experience of our institution (Medical College of Wisconsin, Milwaukee, WI) in managing sinonasal inverting papilloma, examining trends in diagnosis and treatment.

STUDY DESIGN

Retrospective.

METHODS

Thirty-seven patients with inverting papilloma were treated from 1986 to 1999. Demographic data, clinical presentations, pathological findings, surgical approaches and procedures, and recurrence rates were collected retrospectively. Each lesion was categorized into one of four groups based on computed tomography scans and endoscopic findings. This categorization was developed to compare various surgical approaches for tumors in each group.

RESULTS

Thirty-one patients had complete information for inclusion in our study. Nineteen patients were treated endoscopically with an average follow-up of 50 months. Eight patients were in group I, five were in group II, six were in group III, and no patients were in group IV. The recurrence rate for the endoscopic group was 10%. Twelve patients underwent lateral rhinotomy or sublabial degloving approach with an average follow-up of 58 months. Five patients were in group I, three patients were in group II, 1 patient was in group III, and three patients were in group IV. The recurrence rate for the external group was 8%. Difference in recurrence rates (P =.85) was not observed between the endoscopic and external approach groups. Regardless of approach, patients who had primary resection had a recurrence of 0%, whereas those with secondary resection had a recurrence of 17% (P =.10).

CONCLUSIONS

Technological advancements have led to a trend of detecting sinonasal inverting papilloma before extension beyond the sinonasal region. Difference in recurrence rates was not observed between the endoscopic and the external approach groups. Recurrence rates are lower for primary resection versus secondary resection, regardless of surgical approach.

Hepatic hemangiomas with arterioportal shunt: findings at two-phase CT

PURPOSE

To determine the prevalence of arterioportal shunt associated with hepatic hemangiomas, describe the two-phase spiral computed tomographic (CT) findings, and correlate the presence of arterioportal shunt with the size and rapidity of enhancement of hemangiomas.

MATERIALS AND METHODS

The study group consisted of 109 hepatic hemangiomas in 69 patients who underwent two-phase spiral CT during 1 year. CT scans were obtained during the hepatic arterial (30-second delay) and portal venous (65-second delay) phases after injection of 120 mL of contrast material (3 mL/sec). Arterioportal shunts were diagnosed when hepatic arterial phase CT scans showed a wedge-shaped or irregularly shaped homogeneous enhancement in the liver parenchyma adjacent to the tumor and when portal venous phase CT scans showed isoattenuation or slight hyperattenuation, compared with normal liver in that area, and when there was no demonstrable cause of these attenuation differences. The presence of arterioportal shunt in hemangioma was correlated with the size of the tumor and the rapidity of intratumoral enhancement.

RESULTS

Arterioportal shunt was found in 28 (25.7%) of 109 hemangiomas. There was no statistically significant relationship between lesion size and presence of the arterioportal shunt (P =.653). Arterioportal shunt was more frequently found in hemangiomas with rapid enhancement (P <.01).

CONCLUSION

Arterioportal shunts are not uncommonly seen in hepatic hemangiomas at two-phase spiral CT. Hemangiomas with arterioportal shunts tend to show rapid enhancement.

Streptococcus milleri: an organism for head and neck infections and abscess

BACKGROUND

Streptococcus milleri, a commensal organism, has the potential to cause significant morbidity. There is a paucity of published data regarding this organism in the head and neck.

OBJECTIVES

To identify and assess the presentation, treatment, and outcomes of pediatric patients affected by this pathogen.

STUDY DESIGN

Review of the Department of Pathology database at Children's Hospital of Wisconsin, Milwaukee, between 1997 and 1999 identified 26 patients with cultures positive for S milleri group (SMG) bacteria. Retrospective chart analysis examined the demographic data, site of origin of infection, additional organisms cultured, symptoms, treatments, and complications.

RESULTS

Sixteen patients had SMG infections involving the head and neck region. Sites of origin included the paranasal sinuses, dental, facial soft tissues, deep neck spaces, peritonsillar region, and a tracheostomy site. The paranasal sinuses were the most common site in 37% (6/16). Streptococcus milleri was the only isolate in 69% (11) of the infections. Significant local extension occurred in 56% (9/16) of the patients and included the orbit, skull base, cranium, and deep neck spaces. All patients had surgical drainage and 15 also received intravenous antibiotic treatment. One complication of osteomyelitis of the frontal bone occurred with resolution after surgical debridement and intravenous antibiotic treatment.

CONCLUSIONS

Streptococcus milleri can be an aggressive pathogen in the head and neck with a propensity for abscess formation and local extension of the infection in a pediatric population. Surgical drainage with antibiotics is generally successful in management of the condition. However, emerging penicillin resistance and the ability for local extension require suspicion of incomplete treatment if clinical symptoms persist.

Three-dimensional spiral CT cholangiography with minimum intensity projection in patients with suspected obstructive biliary disease: comparison with percutaneous transhepatic cholangiography

BACKGROUND

To evaluate the diagnostic potential of spiral computed tomographic (CT) cholangiography with minimum intensity projection (minIP) in the diagnosis of patients with suspected biliary obstruction.

METHODS

Nine consecutive patients with obstructive biliary disease were enrolled in this study. Spiral CT data (3-mm slice thickness, pitch 1-2:1) obtained 65 s after the start of contrast medium injection (150 mL Ultravist 370, 3 mL/s) were reconstructed at 1-mm intervals. Three-dimensional (3D) CT cholangiography with minIP (3D CTC) was generated with a Siemens software package. The quality of 3D CTC in its ability to demonstrate the anatomic detail, the level of obstruction, and the presence or absence of isolated hepatic segments was evaluated using percutaneous transhepatic cholangiography as a gold standard.

RESULTS

In all patients, 3D CTC demonstrated dilated intrahepatic ducts up to tertiary branches. 3D CTC correctly diagnosed the level of biliary obstruction and demonstrated isolated segments in all patients. In determining the cause of biliary obstruction, one patient with hilar cholangiocarcinoma was misdiagnosed as having biliary invasion by hepatocellular carcinoma.

CONCLUSION

3D CTC with minIP can determine the level and cause of biliary obstruction. 3D CTC can be obtained from regular thin-section helical CT data and may be a strong competitor against diagnostic magnetic resonance cholangiography because of its superior resolution and information on adjacent soft tissues and the duct itself.