Histologically benign but clinically malignant neoplasms in the thorax: CT-pathological overview

The purpose of this article is to review the computed tomography (CT) and histopathological features of uncommon primary neoplasms of the thorax that can manifest clinically malignant features (multiplicity of pulmonary nodules, an invasive nature, and metastases or recurrence after surgery) with little evidence of histological malignancy.

Basal STAT3 activities are negatively correlated with tumor size in papillary thyroid carcinomas

BACKGROUNDS

Signal transducer and activators of transcription-3 (STAT3) plays a critical role in promoting survival and cell growth as well as facilitating angiogenesis and metastasis in several cancers.

AIM

This investigation focused on evaluation of STAT3 activities in human papillary thyroid cancers (PTC).

METHODS

STAT3 activities of nuclear extracts of tumor tissue were measured from 35 PTC patients using enzyme- linked immunosorbent assay-based kits.

RESULTS

STAT3 activities of PTC tissues were significantly lower than those of surrounding normal thyroid tissues [0.36 (interquartile range 0.24-0.72) vs 0.50 (0.29-1.11) arbitrary units, p<0.01]. We further analyzed the association between STAT3 activity and clinicopathologic factors in PTC tissue. Tumors with size ≥2 cm displayed significantly lower STAT3 activities than those <2 cm [0.25 (0.21-0.37) vs 0.53 (0.37-0.61) arbitrary units, p<0.01]. Notably, tumor size was inversely correlated with STAT3 activities in T1799A BRAF mutation-positive cases (Rs=-0.58, p<0.05), but not mutation-negative cases.

CONCLUSIONS

STAT3 activities of PTC measured via DNA binding are suppressed in contrast to other human cancers. Tumor size larger than 2 cm is the only clinicopathologic parameter associated with low STAT3 activity. Moreover, tumor size appears inversely correlated with STAT3 activity, specifically in T1799A BRAF mutation-positive cases.

Relationship between prolactin levels and subjective endocrine-related adverse effects in patients with schizophrenia receiving long-term treatment with amisulpride

INTRODUCTION

We have investigated the categorical prevalence of hyperprolactinemia and examined the relationship between prolactin levels and subjective endocrine-related adverse effects in schizophrenia patients treated with amisulpride during a 1-year period.

METHODS

A total of 111 patients with schizophrenia who were either started on or switched to amisulpride were assessed for prolactin levels and endocrine-related adverse effects using 6 items derived from the Liverpool University neuroleptic side-effect rating scale (LUNSERS) at baseline, 8 weeks, and 1 year.

RESULTS

10 were antipsychotic-naïve, 23 were antipsychotic free for 1 month, 54 discontinued their medication during 1 month prior to study, and 24 maintained their antipsychotics at baseline. At 1 year, hyperprolactinemia was found in 75.9% of men and 85.7% of women. Significant increases in mean prolactin levels at week 8 in both sexes were found; this was followed by a significant decrease over 1 year only in women. The proportions of both sexes with hyperprolactinemia increased from baseline to week 8 but remained unchanged at 1 year. Scores on the endocrine-related items of the LUNSERS improved significantly from baseline to week 8 in both sexes and then remained consistent during maintenance treatment. Prolactin levels were significantly higher in the group with baseline hyperprolactinemia than in the group without baseline hyperprolactinemia at all assessment points.

CONCLUSIONS

Amisulpride commonly induces hyperprolactinemia. Although the percentage of patients with hyperprolactinemia remained unchanged during maintenance treatment, serum prolactin levels significantly decreased among women. Self-reported endocrine-related side effects were not associated with prolactin elevation during amisulpride treatment.

Monitoring of cytomegalovirus-specific CD8+ T-cell response with major histocompatibility complex pentamers in kidney transplant recipients

INTRODUCTION

Cytomegalovirus (CMV) can reactivate causing serious clinical problems during immunosuppression. CMV-specific CD8(+) T cells play an important role in the control of CMV reactivation. Using pentameric major histocompatibility complex (MHC) peptide complexes, we investigated cellular immune responses to CMV among healthy individuals and kidney transplantation recipients in Korea, which is an endemic area of CMV infection.

MATERIALS AND METHODS

Analysis of CMV-specific T cells was performed on 28 healthy individuals and 40 recipients who bore human leukocyte antigen (HLA)-A2 or -A24. CMV pp65 pentamer-binding cells incubated with various monoclonal antibodies were measured by four-color flow cytometry.

RESULTS

Detectable levels of pentamer(+) CD8(+) T cells were present in 109/139 samples (78.4%) that stained with the A*02NLV-pentamer, while 15/67 samples (22.4%) stained with the A*24QYD-pentamer (P < .01). Among patients with HLA-A2, 22/24 (91.7%) samples showing positive CMV antigenemia revealed detectable pentamer(+) CD8(+) T cells, while 87/115 (75.7%) displaying negative CMV antigenemia had detectable pentamer(+) CD8(+) T cells (P = .04). There was no significant difference in percentages of pentamer(+) CD8(+) T cells between patients who did versus who did not experience episodes of CMV infection. The subpopulation of CMV-specific CD8(+) T cells in transplantation recipients was evaluated using phenotypic markers; memory cells comprised the majority of the CMV-specific CD8(+) T-cell population.

CONCLUSION

The A*02NLV-pentamer complex was useful to monitor CMV-specific T cells. However, MHC pentamer-based techniques did not provide a clear distinction between patients who are or are not at risk for CMV infection.

Randomised clinical trial: a comparative study of 10-day sequential therapy with 7-day standard triple therapy for Helicobacter pylori infection in naïve patients

BACKGROUND

The eradication rates following standard triple therapy for Helicobacter pylori infection are declining worldwide. Recent studies have shown that sequential therapy for H. pylori infection yields high cure rates.

AIM

To compare the efficacy and tolerability of a sequential regimen as first-line treatment of H. pylori infection with a standard triple regimen.

METHODS

A total of 348 naïve H. pylori-infected patients from six hospitals in Korea were assigned randomly to standard triple or sequential therapy groups. Standard triple therapy consisted of 20 mg of rabeprazole, 1 g of amoxicillin and 500 mg of clarithromycin, twice daily for 7 days. Sequential therapy consisted of a 5-day dual therapy (20 mg of rabeprazole and 1 g of amoxicillin, twice daily) followed by a 5-day triple therapy (20 mg of rabeprazole, 500 mg of clarithromycin, and 500 mg of metronidazole, twice daily).

RESULTS

The intention-to-treat (ITT) and per-protocol (PP) eradication rates were 62.2% (95% CI 54.8-69.6%) and 76.0% (95% CI 68.5-83.5%) in the standard triple group, and 77.8% (95% CI 71.4-84.2%) and 87.9% (95% CI 82.3-93.5%) in the sequential group, respectively. The eradication rate was significantly higher in the sequential group compared with the standard triple group in both the ITT and PP populations (P = 0.002 and P = 0.013 respectively), whereas the incidence of adverse events was similar.

CONCLUSIONS

Ten-day sequential therapy is more effective and equally tolerated for eradication of H. pylori infection compared with standard triple therapy. Sequential therapy may have a role as first-line treatment for H. pylori infection.

Randomised clinical trial: a comparative study of 10-day sequential therapy with 7-day standard triple therapy for Helicobacter pylori infection in naïve patients

BACKGROUND

The eradication rates following standard triple therapy for Helicobacter pylori infection are declining worldwide. Recent studies have shown that sequential therapy for H. pylori infection yields high cure rates.

AIM

To compare the efficacy and tolerability of a sequential regimen as first-line treatment of H. pylori infection with a standard triple regimen.

METHODS

A total of 348 naïve H. pylori-infected patients from six hospitals in Korea were assigned randomly to standard triple or sequential therapy groups. Standard triple therapy consisted of 20 mg of rabeprazole, 1 g of amoxicillin and 500 mg of clarithromycin, twice daily for 7 days. Sequential therapy consisted of a 5-day dual therapy (20 mg of rabeprazole and 1 g of amoxicillin, twice daily) followed by a 5-day triple therapy (20 mg of rabeprazole, 500 mg of clarithromycin, and 500 mg of metronidazole, twice daily).

RESULTS

The intention-to-treat (ITT) and per-protocol (PP) eradication rates were 62.2% (95% CI 54.8-69.6%) and 76.0% (95% CI 68.5-83.5%) in the standard triple group, and 77.8% (95% CI 71.4-84.2%) and 87.9% (95% CI 82.3-93.5%) in the sequential group, respectively. The eradication rate was significantly higher in the sequential group compared with the standard triple group in both the ITT and PP populations (P = 0.002 and P = 0.013 respectively), whereas the incidence of adverse events was similar.

CONCLUSIONS

Ten-day sequential therapy is more effective and equally tolerated for eradication of H. pylori infection compared with standard triple therapy. Sequential therapy may have a role as first-line treatment for H. pylori infection.

Prognostic factors for idiopathic pulmonary fibrosis: clinical, physiologic, pathologic, and molecular aspects

BACKGROUND

Previous studies identified clinical and physiologic factors of idiopathic pulmonary fibrosis (IPF) that are related to an increased risk of mortality. But there are few studies about histologic and molecular approach.

OBJECTIVE

We investigated whether the C-reactive protein (CRP), fibroblastic foci, phosphorylated Smad2/3 (p-Smad2/3), tumor growth factor-beta (TGF-beta), TGF-beta receptor II (TbetaRII), and the polymorphism of the TGF-beta1 codon 10 are associated with the progression of IPF patients.

DESIGN

Eighty-six IPF patients who underwent surgical lung biopsies were examined. For each patient, clinical and physiologic parameters were investigated, and we performed immunohistochemical staining for p-Smad2/3 and TbetaRII, and genotyping of the TGF-beta1 codon 10 polymorphism.

RESULTS

Age at diagnosis, gender, symptom duration, and smoking status did not show a significant association. However, the amount of smoking (p = 0.002), severe reduction in the percentages of predicted forced vital capacity (p = 0.013) and diffusion lung capacity of carbon monoxide (p = 0.023), CRP (p = 0.009) at diagnosis, and fibroblastic foci (p = 0.026) were associated with a poor prognosis. Cellularity, fibrosis, expression level of p-Smad2/3 and TbetaRII, and genotype of the TGF-beta1 codon 10 polymorphism did not have a statistically significant association with the prognosis.

CONCLUSION

This study confirmed the amount of smoking, abrupt decrease in follow-up pulmonary function parameters, fibroblastic foci, and increased levels of CRP concentration at diagnosis were significantly associated with poor survival. Larger studies are required to confirm all prognostic factors including CRP.

Strain classification of Mycobacterium tuberculosis: congruence between large sequence polymorphisms and spoligotypes

Spoligotyping is used in molecular epidemiological studies, and signature patterns have identified strain families. However, homoplasy occurs in the markers used for spoligotyping, which could lead to identical spoligotypes in phylogenetically unrelated strains. We determined the accuracy of strain classification based on spoligotyping using the six large sequence and single nucleotide polymorphisms-defined lineages as a gold standard. Of 919 Mycobacterium tuberculosis isolates, 870 (95%) were classified into a spoligotype family. Strains from a particular spoligotype family belonged to the same lineage. We did not find convergence to the same spoligotype. Spoligotype families appear to be sub-lineages within the main lineages.

Regulatory CD4(-)CD8(-) double negative T cells

Peripheral αβTCR(+)CD3(+)CD4(-)CD8(-) NK1.1/CD56(-) double-negative (DN) Treg cells are a relatively rare subset of regulatory cells found in both humans and mice, typically comprising less than 5% of the total peripheral T-cell pool. Numerous studies have shown that DN Tregs can inhibit CD4(+) and CD8(+) T-cell responses in vitro and in vivo using a variety of model systems [Zhang et al., Nature Medicine 6:782, 2000; Young et al., Blood 100:3408, 2002; Ford et al., Experimental Medicine 196:261, 2002; Young et al., Journal of Immunology 171:134, 2003; Ford et al., European Journal of Immunology 37:2234, 2007; Zhang et al., Blood 109:4071, 2007; Fischer et al., Blood 105:2828, 2005]. This chapter describes published methods for the phenotypic identification of DN Tregs, their isolation from secondary lymphoid organs of mice or human peripheral blood, activation and expansion, and assays for their ability to suppress T-cell proliferation, induce apoptosis, and promote tolerance to allografts in vivo.

The effect of cytomegalovirus antigenemia titer on the efficacy of preemptive therapy for the prevention of cytomegalovirus disease after kidney transplantation

There is some controversy regarding the exact cytomegalovirus (CMV) antigenemia titer that should be used as a guideline for preemptive anti-CMV therapy. We performed 634 consecutive kidney transplantations between January 2000 and June 2007. Preemptive therapy employed intravenous gancyclovir treatment when the CMV antigenemia titer was >or=50/4x10(5) leukocytes after kidney transplantation. The 634 recipients were allocated into 2 groups according to the peak CMV antegenemia: group A, CMV antigenemia titer<50/4x10(5) (n=550); and group B, >or=50/40x10(5) (n=84). Among the 634 recipients, 264 were positive for CMV antigenemia, and 61 developed symptomatic CMV infections. The incidence of symptomatic CMV infections in group B was significantly higher than in group A. Two cases in both groups developed tissue-proven CMV disease: group A CMV colitis and CMV nephritis, and group B, 2 cases of CMV colitis. Graft and patient survival rates in groups A and B at 5 years posttransplantation were not different. The authors concluded that a CMV antigenemia titer of >or=50/4x10(5) leukocytes can be considered an appropriate guideline for preemptive anti-CMV therapy.

Patients with unresectable hepatocellular carcinoma beyond Milan criteria: should we perform transarterial chemoembolization or liver transplantation?

Patients with unresectable, beyond Milan criteria, hepatocellular carcinoma (HCC) invariably undergo palliative transarterial chemoembolization (TACE). The aim of this study was to compare the outcomes of conventional TACE versus liver transplantation (LT) in unresectable (beyond Milan criteria) HCC. Twelve patients underwent LT and 86 TACE for unresectable, beyond Milan criteria HCC. The inclusion criteria were a single tumor<or=6.5 cm or <or=5 tumors and all tumors<or=5 cm based on initial radiologic findings. We excluded patients with double primary cancers, age>60 years, vascular invasion, or extrahepatic spread. Survival rates were calculated using the Kaplan-Meier method. Multivariate analysis showed that TACE was a prognostic factor for survival (hazard ratio, 16.66, P=.000). The LT group showed significantly better survival than the TACE cohort. Two cases (16.7%) in the LT group recurred at a median time of 13.5 months. Survival rates at 1, 3, and 5 years were 100%, 88.9%, and 76.2% in the LT group, and 85.6%, 45.6%, and 21.4% in the TACE group, respectively. Patients with unresectable, beyond Milan criteria HCC should be given the option to receive LDLT, because LT offers a significantly better likelihood of survival than TACE.

Risk factors for posttransplant lymphoproliferative disorder in pediatric liver transplant recipients with cytomegalovirus antigenemia

Epstein-Barr virus (EBV) infections, associated with posttransplant lymphoproliferative disorder (PTLD) are known to develop in cytomegalovirus (CMV)-infected transplant recipients due to the indirect effects of CMV. This study evaluated risk factors for PTLD among pediatric liver transplant recipients with CMV infections. We reviewed the medical records of 119 patients<or=18 years old who underwent liver transplantation between September 1996 and April 2009. Sixty-six subjects (55.5%) displayed CMV antigenemia during the study period; 15 (12.6%) developed PTLD. Of these, 10 developed PTLD after CMV antigenemia. The other patients (n=5) were excluded due to negative CMV antigenemia. The incidence of PTLD influenced by CMV infection was not significantly different from the incidence of PTLD without underlying CMV (P=.258). There were no differences in age, gender, antiviral prophylaxis, type of liver transplantation, or acute rejection episodes in the incidence of between patients with versus without PTLD. EBV but not CMV high-risk groups were a predictor for the development of PTLD (P=.035). CMV syndrome, tissue-invasive CMV disease, and CMV peak titer were not associated with an increased risk of PTLD. The primary risk factor for PTLD was EBV high-risk patients (donor positive/recipient negative). CMV disease was not associated with PTLD in pediatric liver transplant recipients with CMV infections.

Stereotactic body radiation therapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver cancer in adults and it is frequently associated with cirrhosis. Surgical resection or orthotopic liver transplantation can be curative but only 30-40% of patients may benefit from curative radical treatment. Stereotactic body radiation therapy (SBRT) has emerged as a promising non-invasive therapy for patients with unresectable HCC and it may potentially serve as a bridging therapy for patients awaiting transplantation. There are a limited number of clinical trials examining the use of SBRT in patients with HCC and very good local tumor control and acceptable toxicities have been reported. This article provides an overview on the use of SBRT in the management of HCC.

Differences among sublineages of the East-Asian lineage of Mycobacterium tuberculosis in genotypic clustering

SETTING

The East-Asian lineage of Mycobacterium tuberculosis is composed of five sublineages, and includes the strains from the Beijing spoligotype family. In some studies these strains were highly pathogenic, although other studies did not support this finding.

OBJECTIVE

To determine if the sublineages of the East-Asian lineage of M. tuberculosis differ in their capacity to cause secondary cases, as assessed by genotypic clustering of isolates.

DESIGN

In a population-based study of 545 patients with M. tuberculosis from the East-Asian lineage in San Francisco, we used DNA-based fingerprinting to identify genotypic clustering, which was compared among the different sublineages defined by large sequence polymorphism.

RESULTS

Strains from sublineage 207 had the highest frequency of genotypic clustering. In the multivariate analysis, only patients born in the United States were associated with clustering.

CONCLUSIONS

We found evidence in a univariate analysis that the different East-Asian sublineages of M. tuberculosis have different frequencies of genotypic clustering. The effect size for this difference was unchanged in multivariate analysis, although loss of observations due to missing data resulted in a non-significant P value. It is tantalizing to hypothesize that the different East-Asian sublineages may differ in their capacity to cause secondary cases.

Complete response to radiation therapy of orbital metastasis from hepatocellular carcinoma

The incidence of hepatocellular carcinoma (HCC) is increasing in the United States, and 50%-75% of patients with HCC will develop metastatic disease. Orbital metastases from HCC are extremely rare. We report the case of a 52-year-old male with known metastatic HCC, who presented with severe proptosis and diplopia. An orbital mass was identified on magnetic resonance imaging (MRI) and confirmed to have hypermetabolic activity on positron emission tomography/computed tomography. He received a palliative course of external beam radiation therapy to the right orbit. Intensity modulated radiation therapy (IMRT) was used to allow sparing of critical normal tissues in close proximity to the tumor. One month after completion of IMRT to 58 Gray in 30 fractions delivered over 6 wk, the patient had a complete clinical, radiologic (MRI) and symptomatic response. The patient continues to have local control in the orbit 1.7 years after therapy completion. All critical normal structures were kept below the tolerance dose using IMRT, and no toxicities were observed.

TNFR2-deficient memory CD8 T cells provide superior protection against tumor cell growth

TNF receptor-2 (TNFR2) plays a critical role in promoting the activation and survival of naive T cells during the primary response. Interestingly, anti-CD3 plus IL-2 activated TNFR2(-/-) CD8 T cells are highly resistant to activation-induced cell death (AICD), which correlates with high expression levels of prosurvival molecules such as Bcl-2, survivin, and CD127 (IL-7Ralpha). We determined whether the resistance of activated TNFR2(-/-) CD8 T cells to AICD contributes to more effective protection against tumor cell growth. We found that during a primary tumor challenge, despite initial inferiority in controlling tumor cell growth, TNFR2(-/-) mice were able to more effectively control tumor burden over time compared with wild-type (WT) mice. Furthermore, vaccination of TNFR2(-/-) mice with recombinant Listeria monocytogenes that express OVA confers better protection against the growth of OVA-expressing E.G7 tumor cells relative to similarly vaccinated WT mice. The enhanced protection against tumor cell growth was not due to more effective activation of OVA-specific memory CD8 T cells in vaccinated TNFR2(-/-) mice. In vitro studies indicate that optimally activated OVA-specific TNFR2(-/-) CD8 T cells proliferated to the same extent and possess similar cytotoxicity against E.G7 tumor cells as WT CD8 T cells. However, relative to WT cells, activated OVA-specific TNFR2(-/-) CD8 T cells were highly resistant to AICD. Thus, the enhanced protection against E.G7 in TNFR2(-/-) mice is likely due to the recruitment and activation of OVA-specific memory TNFR2(-/-) CD8 T cells and their prolonged survival at the tumor site.

Yttrium-90 microsphere induced gastrointestinal tract ulceration

Background

Radiomicrosphere therapy (RT) utilizing yttrium-90 (⁹⁰Y) microspheres has been shown to be an effective regional treatment for primary and secondary hepatic malignancies. We sought to determine a large academic institution's experience regarding the extent and frequency of gastrointestinal complications.

Methods

Between 2004 and 2007, 27 patients underwent RT for primary or secondary hepatic malignancies. Charts were subsequently reviewed to determine the incidence and severity of GI ulceration.

Results

Three patients presented with gastrointestinal bleeding and underwent upper endoscopy. Review of the pretreatment angiograms showed normal vascular anatomy in one patient, sclerosed hepatic vasculature in a patient who had undergone prior chemoembolization in a second, and an aberrant left hepatic artery in a third. None had undergone prophylactic gastroduodenal artery embolization. Endoscopic findings included erythema, mucosal erosions, and large gastric ulcers. Microspheres were visible on endoscopic biopsy. In two patients, gastric ulcers were persistent at the time of repeat endoscopy 1–4 months later despite proton pump inhibitor therapy. One elderly patient who refused surgical intervention died from recurrent hemorrhage.

Conclusion

Gastrointestinal ulceration is a known yet rarely reported complication of ⁹⁰Y microsphere embolization with potentially life-threatening consequences. Once diagnosed, refractory ulcers should be considered for aggressive surgical management.

Sinonasal organized hematoma: CT and MR imaging findings

BACKGROUND AND PURPOSE

Sinonasal organized hematoma (OH) is an uncommon, nonneoplastic benign condition that can be locally aggressive. The purpose of this work was to characterize the CT and MR imaging findings of sinonasal OH.

MATERIALS AND METHODS

CT (n = 11) and MR (n = 10) images of 12 patients (9 men and 3 women; mean age, 41 years; range, 12-76 years) with pathologically proved sinonasal OH were retrospectively reviewed. Particular attention was put on the location, shape, size, extent, internal architecture, and enhancement pattern of the lesion and associated sinus wall change.

RESULTS

The lesions were seen as an expansile (n = 9) or nonexpansile (n = 3) mass, ranging in size from 2.2 to 6.0 cm (mean, 4.2 cm), primarily involving the maxillary sinus (n = 11) or nasal cavity (n = 1) unilaterally. The ipsilateral nasal cavity was also involved in 9 of 11 maxillary sinus lesions. Smooth sinus wall erosion other than the medial maxillary sinus wall was noted in 8 lesions. The internal architecture was best displayed on T2-weighted MR images on which all of the lesions were seen as a mixture of marked heterogeneous hypointensity and isointensity, surrounded by a hypointense peripheral rim, reflecting histologic heterogeneity of the lesion composed of hemorrhage, fibrosis, and neovascularization. Marked irregular nodular, papillary, or frondlike enhancement at the areas of neovascularization was also a typical finding seen in all of the lesions.

CONCLUSION

An expansile soft tissue mass, smooth sinus wall erosion, marked heterogeneous signal intensity with a hypointense peripheral rim on T2-weighted MR images, and marked irregular nodular, papillary, or frondlike enhancement are characteristic CT and MR imaging findings of sinonasal OH.

Temporal bone CT findings in Cornelia de Lange syndrome

BACKGROUND AND PURPOSE

Cornelia de Lange syndrome is a rare developmental malformation syndrome with a high prevalence of hearing impairment. The purposes of this study were to describe the characteristic temporal bone CT findings in patients with Cornelia de Lange syndrome and to correlate audiometric data with radiologic findings in these patients.

MATERIALS AND METHODS

Ten children (6 girls and 4 boys; mean age, 42.0 months) who were clinically diagnosed with Cornelia de Lange syndrome (classic, n = 5; mild form, n = 5) were enrolled. Temporal bone CT was prospectively performed, and 32 aspects of each temporal bone CT were analyzed, 21 by direct measurement and 11 by visual inspection. Twenty age-matched children (n = 20 ears) with normal temporal bone CT scans served as a control group. Audiologic tests were also performed on all patients.

RESULTS

Characteristic temporal bone CT findings of Cornelia de Lange syndrome were external auditory canal stenosis, soft-tissue opacification of the hypoplastic tympanomastoid cavity, dysmorphic ossicle, hypoplastic cochlea, and dysplastic vestibule, all of which were more prevalent in patients with the classic form of the disease than in those with the mild form. Children who had more severe structural abnormalities on temporal bone CT had worse hearing levels compared with those without structural abnormalities.

CONCLUSION

Temporal bone CT scans in Cornelia de Lange syndrome could document combined structural abnormalities of the external, middle, and inner ear, which were one of the characteristic clinical manifestations; CT abnormalities were well correlated with the audiometric data.

Thrombus volume comparison between patients with and without hyperattenuated artery sign on CT

BACKGROUND AND PURPOSE

Although the hyperattenuated middle cerebral artery sign is known to be related to acute infarction, the volume of clot associated with it is not known. We investigated whether the presence or absence of hyperattenuated artery sign (HAS) on noncontrast CT (NCCT) can predict the thrombus volume.

MATERIALS AND METHODS

We enrolled 90 consecutive patients with acute infarction who underwent both 5- and 1.25-mm NCCT and CT angiography (CTA). HAS was determined on 5-mm NCCT retrospectively. According to the location of thrombi, the patients were classified into ICA (ICA terminus/ICA and others), M1 (M1/both M1 and M2), and M2 (M2) groups. Thrombus volumes were measured by 1.25-mm NCCT and were compared between patients with and without HAS.

RESULTS

Occlusion of major arteries was seen on CTA in 78 patients. HAS was found in 46 patients (59.0%). The mean thrombus volume was significantly larger in patients with HAS than in those without except for the M2 group (ICA group: [n = 14], 188.7 +/- 122.5 mm(3) versus 39.4 +/- 12.1 mm(3) [P = .022]; M1 group: [n = 42], 128.1 +/- 119.2 versus 56.8 +/- 32.5 [P = .005]; M2 group: [n = 22], 34.7 +/- 32.2 versus 20.0 +/- 20.0 [P = .18]). Thrombus volumes determined by receiver operating characteristic curve analysis were 52.36 mm(3) in the ICA group (sensitivity, 90.9%; specificity, 100%) and 53.96 mm(3) in the M1 group (sensitivity, 88.0%; specificity, 58.8%).

CONCLUSION

Thrombus volumes were significantly larger in patients with HAS than in those without in ICA and M1 occlusions. The detection of HAS may provide an idea concerning rapid and dichotomized estimation of thrombus volume, which may be helpful for treatment decisions in potential candidates for thrombolysis.

Rhabdoid meningioma: clinical features and MR imaging findings in 15 patients

BACKGROUND AND PURPOSE

Rhabdoid meningioma (RM) is a recently described variant of malignant meningioma, with radiologic features currently not well characterized in the medical literature. The purpose of this study was to describe and characterize clinical features and imaging findings associated with RM.

MATERIALS AND METHODS

CT (n = 8) and MR (n = 15) images of 15 patients (4 men and 11 women; mean age, 52 years; range, 22-75 years) with 16 pathologically proved RMs along with associated clinical records were retrospectively reviewed. All of the patients underwent surgical resection and had additional radiation therapy except for 1 patient. After surgery, the patients had follow-up brain MR imaging to evaluate for tumor recurrence.

RESULTS

Nine lesions (56%) were located in the cerebral convexity, and 4 lesions (25%) were located in the parasagittal areas. The tumors were isointense (n = 15) to gray matter on T1-weighted images, whereas they were hyperintense (n = 14) on T2-weighted images. On gadolinium-enhanced T1-weighted images, homogeneous enhancement was seen in 10 lesions, and heterogeneous enhancement was seen in 6 lesions that had cysts. Cystic components were noted in 6 lesions (38%). Severe peritumoral edema was seen in 12 lesions (75%). Nine lesions (56%) had hyperostosis, and 5 of them also had bone destruction. Among the 8 cases with initial CT scans, only 1 had amorphous calcifications (13%). There was only 1 recurrence of RM found during the follow-up period after surgical resection.

CONCLUSION

RMs tend to have prominent peritumoral edema, cystic components, and bone involvement.

MR imaging of metronidazole-induced encephalopathy: lesion distribution and diffusion-weighted imaging findings

BACKGROUND AND PURPOSE

MR imaging features of metronidazole-induced encephalopathy (MIE) have not been fully established. This study was undertaken to determine the topographic distributions and diffusion-weighted imaging (DWI) findings of MIE.

MATERIALS AND METHODS

We retrospectively evaluated the initial MR images (n = 7), including DWI (n = 5), and follow-up MR images (n = 4) after drug discontinuation in 7 patents with clinically diagnosed MIE. The topographic distributions of lesions were evaluated on MR images, and DWI signal intensities and apparent diffusion coefficient (ADC) values of the lesions were assessed.

RESULTS

MR images demonstrated bilateral symmetric T2 hyperintense lesions in the cerebellar dentate nucleus (n = 7), midbrain (n = 7), dorsal pons (n = 6), medulla (n = 4), corpus callosum (n = 4), and cerebral white matter (n = 1). Brain stem lesions involved the following: tectum (n = 5), tegmentum (n = 4), red nucleus (n = 3) of the midbrain, vestibular nucleus (n = 6), and a focal tegmental lesion involving the superior olivary nucleus (n = 6) and abducens nucleus (n = 4) of the pons and vestibular nucleus (n = 4) and inferior olivary nucleus (n = 1) of the medulla. DWI (n = 5) showed isointensity or hyperintensity of lesions, and the decreased ADC value was found only in the corpus callosum lesions (n = 2). All detected lesions were completely reversible at follow-up except for the single corpus callosum lesion with an initial low ADC value.

CONCLUSION

Brain lesions were typically located at the cerebellar dentate nucleus, midbrain, dorsal pons, medulla, and splenium of the corpus callosum. According to DWI, most of the lesions in MIE probably corresponded to areas of vasogenic edema, whereas only some of them, located in the corpus callosum, corresponded to cytotoxic edema.