Enhanced Computed Tomography Imaging Research Articles

Stanford B型大動脈解離に対してステントグラフト内挿術を選択し良好な転帰をたどった2症例(Endovascular aortic repair for Stanford type B aortic dissection in two cases with good outcomes)

要旨Stanford B型大動脈解離（B型解離）へのステントグラフト内挿術（thoracic endovascular aortic repair: TEVAR）は安全，有効とされる。症例1は72歳の男性。偽腔閉塞型急性B型解離と診断し，内科治療を行ったがulcer like projection（ULP）を認めTEVARを行った。症例2は慢性偽腔開存型B型解離の50歳の男性。既存解離腔に加え，新規解離腔が出現，三腔解離を呈した。内科治療を行ったが，偽腔拡大による真腔圧迫を認めたため，第20病日にTEVARを行った。B型解離は内科治療が原則だが，近年，TEVARを選択する例が増加し，良好な結果が報告されている。また三腔解離例は稀で，本邦でのTEVAR施行例は少ない。

Intrarenal urothelial cancers confused as infiltrative renal masses: Report of 22 cases and literature review.

Distinguishing infiltrative renal masses (IRMs) from intrarenal urothelial cancers (IUCs) is critically important, but may be challenging for any radiologist or urologist. The present study aimed to summarize the clinical, imaging and pathological characteristics of IRM, which were postoperatively confirmed as IUC. The analysis was performed using the records of 22 patients who were preoperatively diagnosed with IRM but the results of percutaneous biopsies or postoperative pathological analyses led to diagnoses of urothelial cancers (UCs) from January 2011 to December 2017. The demographic data, computed tomography (CT) imaging features and pathological characteristics were evaluated. The present study also reviewed the literature concerning the IRM and IUC. The mean age of patients was 62 years and 86.4% of them were >55 years. The sex and tumor side distributions were equal. Hematuria and/or flank pain were observed in 86.4% of patients. All patients exhibited endophytic solid renal masses with unclear tumor boundaries on CT images. The kidneys of 81.8% of patients maintained their normal shape while mild alternations were observed in 18.2% of cases. A total of 81.8% of patients maintained the reniform shape and 18.2% exhibited mild contour change. Of all patients, all tumors exhibited less or equal attenuation on unenhanced CT images and they were mildlyimproved on enhanced CT. A total of 6 cases were confirmed by biopsy, when patients underwent laparoscopic nephroureterectomy instead of radical nephrectomy. The remaining 16 patients underwent laparoscopic nephrectomy but the postoperative pathological diagnoses revealed the presence of UCs. All postoperatively confirmed cancers were stages T3 and T4 (62.5 and 37.5%, respectively). UCs should be suspected in middle aged or elderly middle-elderly patients presenting renal masses with endophytic solid unclear tumor boundary on unenhanced and slightly enhanced CT images, accompanied with hematuria and/or flank pain. Preoperative biopsy is preferred for complicated cases.

Short-term efficacy of iodine-125 radioactive seed implantation therapy for hypoxic tumors

Objective To study the short-term efficacy of computed tomography (CT)-guided iodine-125(125I) radioactive seed implantation in the treatment of hypoxic tumors. Methods Twenty-two patients treated with 125I radioactive seed implantation in our department from 2014 to 2016 were divided into hypovascular tumor group (hypoxic group, n=12) and hypervascular tumor group (non-hypoxic group, n=10) based on the hemodynamics of solid tumor evaluated by color Doppler ultrasound. The enhanced CT images were loaded to the three-dimensional particle implantation planning system for preoperative planning. After 125I radioactive seed implantation, the D90 for target volume was verified to be 106-128 cGy. Treatment outcomes were evaluated according to the World Health Organization criteria at 1-3 months after surgery. Results In all the patients, the overall response rate was 82% at 3 months after surgery. There were no significant differences in response (complete response+ partial response) rates at 1, 2, or 3 months after surgery between the hypoxic group and the non-hypoxic group (P=0.840, 0.696, 0.840). Conclusions In the treatment of solid malignant tumor, 125I radioactive seed implantation can overcome the resistance of hypoxic tumor to radiotherapy in vitro and achieve satisfactory short-term efficacy. Key words: Iodine-125 radioactive seed; Hypoxic tumor; Short-term efficacy

Preoperative CT texture analysis of gastric cancer: correlations with postoperative TNM staging

To explore the role of computed tomography (CT) texture analysis in predicting pathologic stage of gastric cancers. Preoperative enhanced CT images of 153 patients (112 men, 41 women) with gastric cancers were reviewed retrospectively. Regions of interest (ROIs) were manually drawn along the margin of the lesion on the section where it appeared largest on the arterial and venous CT images, which yielded texture parameters, including mean, maximum frequency, mode, skewness, kurtosis, and entropy. Correlations between texture parameters and pathological stage were analysed with Spearman's correlation test. The diagnostic performance of CT texture parameters in differentiating different stages was evaluated using receiver operating characteristic (ROC) analysis. Maximum frequency in the arterial phase and mean, maximum frequency, mode in the venous phase correlated positively with T stage, N stage, and overall stage (all p<0.05) of gastric cancer. Entropy in the venous phase also correlated positively with N stage (p=0.009) and overall stage (p=0.032). Skewness in the arterial phase had the highest area under the ROC curve (AUC) of 0.822 in identifying early from advanced gastric cancers. Multivariate analysis identified four parameters, including maximum frequency, skewness, entropy in the venous phase, and differentiation degree from biopsy, for predicting lymph node metastasis of gastric cancer. The multivariate model could distinguish gastric cancers with and without lymph node metastasis with an AUC of 0.892. Multiple CT texture parameters, especially those in the venous phase, correlated well with pathological stage and hold great potential in predicting lymph node metastasis of gastric cancers.

CT scan contrast enhancement using singular value decomposition and adaptive gamma correction

We propose in this paper a new enhancement algorithm dedicated to dark computed tomography (CT) scan based on discrete wavelet transform with singular value decomposition (DWT–SVD) followed by adaptive gamma correction (AGC). Discrete wavelet transform (DWT) is considered to decompose the input dark CT image in four sub-bands. Singular value decomposition (SVD) is used in order to compute the corresponding singular value matrix of low–low (LL) sub-band image. The enhanced LL sub-band is determined by scaling the singular value matrix of original LL sub-band by an adequate correction factor, followed by inverse SVD. For a further contrast improvement, the new enhanced LL sub-band image is processed using an AGC algorithm. Finally, the obtained LL sub-band image undergoes inverse DWT together with the unprocessed sub-bands to generate the final enhanced image. This proposed method has the advantage of being fully automatic and could be applied for dark input images with either low or moderate contrast. Different dark CT images are considered to compare the performance of our proposed method to three other enhancement techniques using both objective and subjective assessments. Simulation results show that our proposed algorithm consistently produces good contrast enhancement, with best brightness and edges details conservation and with minimum added distortions to the enhanced CT images.

Morphometric analyses of small accessory liver lobes using radiological imaging

AimTo investigate the prevalence and morphometric characteristics of small accessory liver lobes using computed tomography (CT) and magnetic resonance (MR) images. Material and methodsThe study population comprised 3269 patients (1671 men and 1598 women; mean age, 67.1 ± 15.2 years) who had undergone abdominal CT examination. Small accessory liver lobes were identified after verification of their continuity with the liver parenchyma on CT images. Their imaging characteristics were analyzed and presented. ResultsThirty-five small accessory liver lobes in 33 patients (1.01%; 25 men and 8 women, 71.0 ± 11.7 years) were identified. Thirty-one patients (93.9%) had solitary lesions most frequently identified on liver segment 6 (80.0%) with the mean size 9.6 ± 4.8 mm. These showed iso (62.9%), hyper (28.6%), or hypoattenuation (8.6%) on unenhanced CT. Enhanced CT images were available for 29 lesions. Enhancement of 12 lesions (41.4%) was similar to that of the liver parenchyma, whereas 17 lesions (58.6%) showed poor enhancement. MR images were available for 10 lesions, which showed hyperintensity (50.0%) on T2-weighted images and poor enhancement (50.0%). The characteristics of other lesions were similar to those of the liver parenchyma. During observation (mean, 77.0 months; n = 29), 19 lesions remained the same size (65.5%), 5 new lesions increased size (17.2%), and 5 showed reduced size (17.2%). ConclusionSmall accessory liver lobes, commonly located on segment 6, were frequently observed and did not necessarily show the same findings as the liver parenchyma. Time-dependent morphological changes were observed in approximately one-third of the lesions.

Texture analysis of CT imaging for assessment of esophageal squamous cancer aggressiveness.

To explore the role of texture analysis of computed tomography (CT) images in preoperative assessment of esophageal squamous cell carcinoma (ESCC) aggressiveness. Seventy-three patients with pathologically confirmed ESCC underwent unenhanced and contrast enhanced CT imaging preoperatively. Texture analysis was performed on unenhanced and contrast enhanced CT images, respectively. Six CT texture parameters were obtained. One-way analysis of variance or independent-samples t-test (normality), independent-samples Kruskal-Wallis test or Mann-Whitney U test (non-normality), binary Logistic regression analysis (multivariable), Spearman correlation test, receiver operating characteristic (ROC) curve analysis and intraclass correlation coefficient (ICC) were used for statistical analyses. Kurtosis was an independent predictor for T stages (T1-2 vs. T3-4) as well as overall stages (I-II vs. III-IV) based on unenhanced CT images, while entropy was an independent predictor for T stages (T1-2 vs. T3-4), lymph node metastasis (N- vs. N+) and overall stages (I/II vs. III/IV). Skew and kurtosis based on unenhanced CT images showed significant differences among N stages (N0, N1, N2 and N3) as well as 90th percentile based on contrast enhanced CT images. In correlation with T stage of ESCC, kurtosis and entropy significantly correlated with T stage both on unenhanced and contrast enhanced CT images. Reversely, entropy and 90th percentile based on contrast enhanced CT images showed significant correlations with N stage (r: 0.526, 0.265; both P<0.05), as well as overall stage (r: 0.562, 0.315; both P<0.05). For identifying ESCC with different T stages (T1-2 vs. T3-4), lymph node metastasis (N- vs. N+) and overall stages (I/II vs. III/IV), entropy based on contrast enhanced CT images, showed good performance with area under ROC curve area under curve (AUC) of 0.637, 0.815 and 0.778, respectively. Texture analysis of CT images held great potential in differentiating different T, N and overall stages of ESCC preoperatively, while failed to assess the differentiation degrees.

Prophylactic accessory renal artery coil embolization for prevention of type II endoleak following endovascular aneurysm repair: a case report

BackgroundPrior reports indicate that intentional coverage of the accessory renal arteries (ARAs) with a diameter larger than 3 mm during endovascular aneurysm repair (EVAR) increases risk of additional treatment for type II endoleak. Here, we report a case of prophylactic coil embolization for a 4 mm ARA originating from an abdominal aortic aneurysm.Case presentationA 76-year-old woman was admitted to our hospital after noticing an abdominal pulsatile mass. Computed tomography (CT) imaging revealed an abdominal aortic aneurysm (AAA) with a maximum diameter of 53 mm. Preoperative CT scan showed a right ARA, 4 mm in diameter, which was considered likely to lead to type II endoleak following EVAR. ARA coil embolization was performed at the time of EVAR. We observed no endoleaks and no infarct of the inferior pole of the right kidney on completion angiography. The postoperative course was uneventful, and the patient was discharged 7 days later. Postoperative eGFR (58.4 ml/min) was not significantly different from preoperative level (56.7 ml/min). After EVAR, blood pressure was under control, and no additional anti-hypertensive medicines were required. Postoperative enhanced CT image showed that the distal portion of the ARA was well perfused without type II endoleak from ARA.ConclusionsProphylactic coil embolization for a large ARA originating from an abdominal aortic aneurysm appears to be safe and effective in preventing type II endoleak following EVAR.

Myoepithelial carcinoma of the salivary gland: pathologic and CT imaging characteristics (report of 10 cases and literature review)

To summarize the pathologic and computed tomography (CT) imaging characteristics of myoepithelial carcinoma in the salivary gland. Ten patients with myoepithelial carcinoma of the salivary gland underwent enhanced CT scanning, and the pathologic and CT imaging features were evaluated, including the pathologic type, size, margin morphology, and enhancement pattern of the lesions. Myoepithelial carcinoma had a multinodular or lobulated outline. The cut surfaces were gray-brown with no or incomplete capsules, and visible bleeding was observed in some cases. The pathologic cell type of the tumor was spindle-shaped, clear, plasmacytoid, or epithelioid cells or a mixture of cell types. Nonenhanced CT imaging showed an irregular lobulated or multinodular lesion with ill-defined margins and inhomogeneous attenuation and punctate calcification in a minority of the lesions. The enhanced CT imaging results revealed moderate and intense inhomogeneous enhancement, including cystic and slit-like regions with no enhancement, intense nodular enhancement, and small tortuous vessels in the arterial phase. The pathologic features and CT imaging findings of myoepithelial carcinoma were characteristic, and familiarity with these imaging findings might aid in the diagnosis of this entity.

Imaging findings of adrenal primitive neuroectodermal tumors: a series of seven cases.

To explore the imaging features of adrenal primitive neuroectodermal tumors (PNETs). This retrospective study included seven patients with surgically and pathologically confirmed adrenal PNETs. Among them, six underwent computed tomography (CT)scans, and one underwent magnetic resonance imaging. The imaging findings, including size, shape, margin, hemorrhage, calcification, cystic degeneration, regional lymph nodes involvement, tumor thrombus formation and enhancement pattern, were retrospectively analyzed. Among the seven adrenal PNET patients, six were male, and one was female. The median age was 26years (range 2-56years). The disease generally presented with either insidious symptoms (n=4) or non-specific symptoms, including right flank pain (n=1) and left upper abdominal discomfort (n=2). On the pre-enhanced CT images, the tumor usually appeared as a well-defined, rounded or oval, heterogeneous mass without calcification. Certain tissue characteristics, such as cystic degeneration (n=5), capsule (n=4) and hemorrhage (n=2), were observed. Regional lymph node involvement was observed in three cases, and renal vein thrombus was observed in one case. All cases showed mild heterogeneous enhancement of the tumor on the enhanced CT images. An adrenal PNET commonly presents as a relatively large, well-defined, heterogeneous mass with cystic degeneration, necrosis and a characteristic mild contrast-enhancement pattern on multiphase enhanced images. PNET should be considered when the diagnosis of common tumors is not favored by signs on images. This study was approved by the medical ethics committee of Xiangya Hospital, Central South University. The approval number is 201512538.

In situ synthesis of graphene oxide/gold nanorods theranostic hybrids for efficient tumor computed tomography imaging and photothermal therapy

Graphene oxide/gold nanorod (GO/GNR) nanohybrids were synthesized with a GO- and gold-seed-mediated in situ growth method at room temperature by mixing polystyrene sulfonate (PSS) functionalized GO, secondary growth solution, and gold seeds. Compared with ex situ preparation methods of GO/GNRs or graphene (G)/GNRs, the in situ synthesis of GO/GNRs addressed the issue of the aggregation of the GNRs before their attachment onto the GO. The method is straightforward and environment-friendly. The GO/GNRs showed a remarkable photothermal effect in vitro. The temperature of the GO/GNR nanohybrids increased from 25 to 49.9 °C at a concentration of 50 μg/mL after irradiation with an 808-nm laser (0.4 W/cm2) for 6 min. Additionally, the GO/GNRs exhibited good optical and morphological stability and photothermal properties after six cycles of laser irradiation. Upon injection of the GO/GNRs into xenograft tumors, excellent computed tomography (CT) imaging properties and photothermal effect were obtained. The preclinical CT agent iohexol was combined with the GO/GNRs and further enhanced CT imaging. Therefore, the GO/GNR nanohybrids have great potential for precise CT-image-guided tumor photothermal treatment.

Bioresponsive and fluorescent hyaluronic acid-iodixanol nanogels for targeted X-ray computed tomography imaging and chemotherapy of breast tumors

Nanotheranostics is a rapidly growing field combining disease diagnosis and therapy, which ultimately may add in the development of ‘personalized medicine’. Here, we designed and developed bioresponsive and fluorescent hyaluronic acid-iodixanol nanogels (HAI-NGs) for targeted X-ray computed tomography (CT) imaging and chemotherapy of MCF-7 human breast tumors. HAI-NGs were obtained with a small size of ca. 90nm, bright green fluoresence and high serum stability from hyaluronic acid-cystamine-tetrazole and reductively degradable polyiodixanol-methacrylate via nanoprecipitation and a photo-click crosslinking reaction. Notably, paclitaxel (PTX)-loaded HAI-NGs showed a fast glutathione-responsive drug release. Confocal microscopy displayed efficient uptake of HAI-NGs by CD44 overexpressing MCF-7 cells via a receptor-mediated mechanism. MTT assays revealed that HAI-NGs were nontoxic to MCF-7 cells even at a high concentration of 1mg/mL whereas PTX-loaded HAI-NGs exhibited strong inhibition of MCF-7 cells. The in vivo pharmcokinetics, near-infrared imaging and biodistribution studies revealed that HAI-NGs significantly prolonged the blood circulation time and enhanced tumor accumulation of PTX. Interestingly, significantly enhanced CT imaging was observed for MCF-7 breast tumors in nude mice via either intratumoral or intravenous injection of HAI-NGs as compared to iodixanol. HAI-NGs fluoresence was distributed thoughout the whole tumor indicating deep tumor penetration. PTX-loaded HAI-NGs showed effective suppression of tumor growth with little systemic toxicity. HAI-NGs appear as a “smart” theranostic nanoplatform for the treatment of CD44 positive tumors.

Percutaneous Microwave Ablation Liver Partition and Portal Vein Embolization for Rapid Liver Regeneration: A Minimally Invasive First Step of ALPPS for Hepatocellular Carcinoma.

Percutaneous Microwave Ablation Liver Partition and Portal Vein Embolization for Rapid Liver Regeneration: A Minimally Invasive First Step of ALPPS for Hepatocellular Carcinoma.

Enhanced CT imaging of human laryngeal squamous carcinoma and indirect CT lymphography imaging using PEGylated PAMAM G5·NH2-entrapped gold nanoparticles as contrast agent

Abstract We report the utilization of dendrimer-entrapped gold nanoparticles (Au DENPs) modified by polyethylene glycol (PEG) with good biocompatibility for enhanced computed tomography (CT) imaging of human laryngeal squamous carcinoma and indirect CT lymphography imaging in New Zealand rabbits. In this work, PEG-modified amine-terminated poly(amidoamine) dendrimers of generation 5 (G5·NH2) were used as templates to synthesize Au DENPs, followed by acetylation of the remaining dendrimer terminal amines to generate PEGylated Au DENPs. The formed PEGylated Au DENPs was used for both enhanced CT imaging of human laryngeal squamous carcinoma cells (Hep-2 cells) and the xenograft tumor mode, and indirect CT lymphography imaging in New Zealand rabbits. In vitro cytotoxicity assay, flow cytometry analysis, and cell morphology observation revealed that the formed PEGylated Au DENPs were non-cytotoxic at a Au concentration up to 400 μM for 24 h and indicated their good biocompatibility. Transmission electron microscopy data confirmed that the PEGylated Au DENPs was uptaken dominantly by the lysosomes of the cells. The PEGylated Au DENPs enabled not only enhance CT imaging of a xenograft tumor model in nude mice after intravenous injection of the particles, but also effective indirect CT lymphography imaging in rabbits. These findings suggest that the designed PEGylated Au DENPs can be used as a potentially effective contrast agent for CT imaging of various biological systems and different kinds of carcinoma, especially lymphatic mapping and human laryngeal squamous carcinoma.

Size-Dependent Biodistribution of lodinated Oil Nanoemulsions Observed by Dual-Modal Imaging in Rats.

Sizes of nanoscale contrast agents play an important role in targeting specific organs and distribution in organisms. lodinated oil nanoemulsions with uniform size distribution and containing indocyanine green (ICG) fluorescent dye (25 nm, 60 nm, 100 nm) were synthesized by stirring, combined with ultrasonic emulsification technique. Rats were intravenously injected with the iodinated oil nanoemulsions with different sizes, used as contrast agents, and investigated with enhanced computed tomography (CT) and fluorescence imaging. Through experiments, the distribution and metabolism of the contrast agents in rat's bodies were studied, and their influence on enhanced CT imaging of different organs was compared. The results demonstrated that target accumulating organs for the iodinated oil nanoemulsions were liver and spleen, with obvious dosage-dependence. Large sized nanoemulsion preferred to accumulate into spleen, and liver, and the phagocytosis was getting weaker with the decrease of the nanoemulsion size. The CT imaging of the inferior vena cava was rapidly enhanced and reached the highest point after administration of the nanoemulsion. The nanoemulsion gradually gathered and metabolized in the spleen and liver, resulting in rapidly decreased CT imaging, with weak rebound, of the inferior vena cava.

CT findings of adrenal schwannoma

To analyse the computed tomography (CT) imaging features of patients with adrenal schwannoma. Eight cases of adrenal schwannoma confirmed by histopathology were included in this study. All eight patients had undergone multiphase CT examinations. The features of the adrenal schwannoma in the CT images were analysed retrospectively in detail, including size, shape, margin, radiodensity, calcification, and enhancement pattern. There were six male and two female patients, with a median age of 44.5 years (range, 25-52 years). Two patients complained of right flank pain, and two with left upper abdominal discomfort, while the remaining patients were diagnosed by routine ultrasound examinations. On unenhanced CT images, all cases of adrenal schwannoma were well circumscribed, rounded or oval, heterogeneous masses with cystic components, with two cases exhibiting calcification, and three cases with septa. On enhanced CT images, all cases displayed mild heterogeneous enhancement of the tumour during the arterial phase, and progressive enhancement during the portal venous phase and equilibrium phase. Adrenal schwannoma commonly presents as a well-defined unilateral mass with cystic degeneration, septa, and a characteristic progressive contrast-enhancement pattern on multiphase enhanced scans.

Abstract WP365: Role of Enhanced CT Findings in Endoscopic Surgery for Intracerebral Hematoma

Objective: In our institute, endoscopic aspiration of hematoma is often performed for acute treatment of intracerebral hematoma (ICH). In some cases, hemostasis is technically difficult to perform during endoscopy, and post-operative hemorrhage may occur. We examined the association between perioperative complications associated with endoscopic surgery for acute ICH, and radiological findings on enhanced computed tomography (CT). Methods: Subjects were 471 patients diagnosed with hypertensive ICH who had been admitted and treated in our institute within 72 hours from onset, between 2012 and 2015. Enhanced CT imaging was performed at admission, and radiological enhancement signs (RES) were defined as CT angiography spot signs in the arterial phase, or contrast extravasation in the parallel phase. RES-positive subjects were grouped and compared with an equal number of RES-negative subjects, and the association between perioperative complications and RES was analyzed. Results: The RES-positive group included 39 subjects; endoscopic surgery was performed in 16 of the 39 subjects. Postoperative hemorrhage occurred in 6 of the 16 subjects. No hemorrhagic complications were found in the RES-negative group. Follow-up CT after 24 hours showed hematoma expansion in 20 of 26 subjects in the RES-positive group and in only 1 of the 39 subjects of the RES-negative group. Statistical analyses showed that the RES-positive group had a significantly shorter duration between the onset of ICH and CT scan and significantly larger hematoma volume, compared with the RES-negative group. Multivariate analysis identified the presence of RES as a significant risk factor of postoperative hemorrhage or hematoma expansion on follow-up CT. Conclusion: CT angiography spot signs or contrast extravasation positive signs were observed with a shorter duration between ICH onset and CT scan, and larger hematomas. These signs may be an important predictive factor for hematoma expansion, as well as a significant risk factor of postoperative hemorrhage after endoscopic surgery for ICH.

Size-Tuning Ionization To Optimize Gold Nanoparticles for Simultaneous Enhanced CT Imaging and Radiotherapy.

Computed tomography (CT) contrast and radiosensitization usually increase with particle sizes of gold nanoparticles (AuNPs), but there is a huge challenge to improve both by adjusting sizes under the requirements of in vivo application. Here, we report that AuNPs have great size-dependent enhancements on CT imaging as well as radiotherapy (RT) in the size range of 3-50 nm. It is demonstrated that AuNPs with a size of ∼13 nm could simultaneously possess superior CT contrast ability and significant radioactive disruption. The Monte Carlo method is further used to evaluate this phenomenon and indicates that the inhomogeneity of gold atom distributions caused by sizes may influence secondary ionization in whole X-ray interactions. In vivo studies further indicate that this optimally sized AuNP improves real-time CT imaging and radiotherapeutic inhibition of tumors in living mice by effective accumulation at tumors with prolonged in vivo circulation times compared to clinically used small-molecule agents. These results suggest that ∼13 nm AuNPs may serve as multifunctional adjuvants for clinical X-ray theranostic application.

Incremental value of contrast enhanced computed tomography on diagnostic accuracy in evaluation of small pulmonary ground glass nodules.

To evaluate the information gain by the application of both non-contrast and contrast enhanced computed tomography (CT) with extended mediastinal display window settings in the evaluation of pure ground glass nodules (pGGNs) and or mixed ground glass nodules (mGGNs) in the context of pre-invasive or early stage lung adenocarcinoma. One hundred and fifty patients with ground glass nodules (GGNs) and mGGNs, with contrast enhanced CT scans within 2 weeks of thoracic surgery were included in the study. Quantitative evaluation of all nodules was performed in a conventional mediastinal window (CMW) and an extended mediastinal window (EMW) both on non-contrast images and contrast-enhanced images. Contrast-enhanced images with CMW demonstrated amplification of solid portion in 23 (43%), 41 (77%) with EMW out of 53 minimally invasive adenocarcinoma (MIA) nodules, and in 34 of 37 (91%) of invasive adenocarcinoma (IAC) nodules. Using the increase in size of solid portion of the nodule measured on the enhanced CT images with EMW, area under the receiver operating characteristic (ROC) curve of 0.872 and 0.899 was utilized for differentiating between the pre-invasive nodules and MIA and between MIA and IAC nodules, respectively. Statistically significant differences existed between the pre-invasive and the MIA groups, and MIA and the IAC groups in smaller nodules (P<0.01). Comparative quantitative analysis of the pre and post contrast images can help differentiate between atypical adenomatous hyperplasia (AAH), adenocarcinoma in situ (AIS), MIAs, and IACs. Extension of the CT mediastinal window setting improves the evaluation of small GGNs, and can augment the diagnostic accuracy when evaluating small pGGNs and mGGNs.

Primary Pulmonary Synovial Sarcoma in a Tertiary Referral Center: Clinical Characteristics, CT, and 18F-FDG PET Findings, With Pathologic Correlations.

The purpose of this study was to describe the patient characteristics, computed tomography (CT) and F-fluorodeoxyglucose positron emission tomography (FDG PET) findings, and clinical outcomes of primary pulmonary synovial sarcoma (PPSS), together with their pathologic correlations. The medical records of 14 patients with pathologically proven PPSS in a tertiary hospital from January 1997 to December 2014 were retrospectively reviewed. The CT findings were evaluated. The maximum standardized uptake value (maxSUV) of the tumors was obtained, and clinical outcomes with respect to tumor recurrence and mortality were assessed by Kaplan-Meier analysis. The median tumor size was 10.2 cm and the most common anatomic location was the lung followed by the pleura/chest wall and mediastinum. Most of the tumors appeared as single lesions and had circumscribed margins. All the cases showed heterogeneous enhancement with necrotic or cystic portions, and intratumoral vessels were frequently seen. Half of the tumors had intratumoral calcifications, and tumor rupture, pleural/chest wall extension, and pleural effusion occurred frequently. However, lymph node enlargement was rare. The median maxSUV of the tumors was 4.35. Patient outcomes with respect to tumor recurrence (n = 8, 57.1%) and death (n = 3, 21.4%) were poor despite their young age, and the mean follow-up period was 28.5 months.In conclusion, PPSS usually occurs in young adults, generally in the lung, presents as a large, circumscribed mass, and tumor rupture or extension of the pleura/chest wall may occur. The tumors often contain calcifications and vessels; they may exhibit triple attenuation on enhanced CT images, and clinical outcomes are poor.