Diagnostic performance of percutaneous core needle lung biopsy under multi-CT fluoroscopic guidance for ground-glass opacity pulmonary lesions

Objective

The diagnostic performance of percutaneous core needle lung biopsy under multi-CT fluoroscopic guidance for ground-glass opacity (GGO) pulmonary lesions was evaluated.

Materials and methods

Out of 90 patients who underwent CT fluoroscopy-guided core needle biopsy of GGO lesions at our institution, the biopsy results and the final diagnoses were retrospectively compared in 67 patients with available data (one lesion per patient). Diagnostic performance was also compared according to the lesion size (≤10 mm (n = 8) versus 11-20 mm (n = 42) versus >20 mm (n = 17)), the percentage of GGO component (50-90% (n = 31) versus >90% (n = 36)), and the length of needle path (≤7 cm (n = 45) versus >7 cm (n = 22)). Finally, all 90 cases were reviewed for complications.

Results

The overall sensitivity, specificity, and accuracy were 97%, 100%, and 97%, respectively. The diagnostic sensitivity and accuracy tended to be lower in smaller lesions (≤10 mm; 86 and 88%, 11-20 mm; 97 and 98%, >20 mm; 100 and 100%, respectively, p > 0.05), and in lesions with lower percentage of GGO component (50-90%; 93 and 94%, >90%; 100 and 100%, respectively, p = 0.21), but statistical significances were not reached. The sensitivity and accuracy were not significantly affected by the length of needle path (≤7 cm; 98 and 98%, >7 cm; 95 and 96%, respectively, p = 1.00). Fourteen patients (16%) developed pneumothoraces, and 13 patients (14%) experienced mild hemoptysis, all of which resolved conservatively.

Conclusion

The diagnostic performance was satisfactory, and it was considered that the procedure was appropriate for GGO lesions regardless of lesion size, the percentage of GGO component, or the length of needle path. The procedure was also feasible without any major complications.     

Focal interstitial fibrosis manifesting as nodular ground-glass opacity: thin-section CT findings

The purpose of this study was to describe the thin-section computed tomographic (CT) features of focal interstitial fibrosis manifesting as nodular ground-glass opacity (GGO) and its changes during follow-up. The thin-section CT findings of pathologically proven focal interstitial fibrosis manifesting as nodular GGO were retrospectively evaluated in nine patients (five women and four men; mean age, 59.3 years; age range, 34–81 years). The thin-section CT findings of each lesion were analyzed for multiplicity, location, shape, margin characteristics, pleural retraction or vascular convergence, size and internal attenuation, lesion internal features and lesion changes on follow-up CT scans (mean 90 days, range 5 to 215 days). All lesions manifested as a solitary nodular GGO (100%), and seven of the nine lesions (77.8%) were located in the upper lobe. Focal interstitial fibrosis was round or oval in shape in five cases (55.6%), complex in shape in three cases (33.3%) and polygonal in one case (11.1%). Lesion margins were smooth in five patients (55.6%), irregular in three (33.3%) and spiculated in one (11.1%). Pleural retraction or vascular convergence was present in two patients (22.2%). Lesions measured 4.8 mm to 25.5 mm (mean, 11.5 mm) and had attenuations ranging from −151 to −699 HU (mean, −514.7 HU). Eight (88.9%) manifested as pure nodular GGOs and one as mixed GGO with a spiculated margin. In all patients, no lesion changes were observed in follow-up CT scans. Focal interstitial fibrosis manifesting as nodular GGO usually presents as a solitary nodule with pure GGO on thin-section CT, which does not change significantly during follow-up.     

Identification and characterization of focal ground-glass opacity in the lungs by high-resolution CT using thin-section multidetector helical CT: experimental study using a chest CT phantom

Purpose The aim of this study was to investigate how much the radiation dose can be reduced for the identification and characterization of focal ground-glass opacities (GGOs) by high resolution computed tomography (HRCT). Materials and methods A chest CT phantom including GGO nodules was scanned with a 40-detector CT scanner. The scanning parameters were as follows: tube voltage 120 kVp; beam collimation 32 × 1.25 mm; thickness and intervals 1.25 mm; tube current and rotation time 180, 150, 120, 90, 60, and 30 mA. 180 mA was the standard. Using a three-point scale at different currents, we visually evaluated image quality. Furthermore, we carried out observer performance tests using receiver operating characteristic (ROC) analysis to evaluate the ability to identify GGO nodules at each current. Results By visual analysis, the scores for all particulars were significantly lower on images obtained at less than 120 mA than at 180 mA (Steel’s test, P < 0.05). There was no statistically significant difference in any particulars other than artifact on images obtained at 180, 150, and 120 mA. By ROC analysis there was no statistical difference in the Az value to identify GGO nodules on images obtained at 180, 150, 120, 90, or 60 mA. However, the Az value at 30 mA was significantly lower than at 180 mA (Dunnett’s test, P < 0.01). Conclusion The minimum current necessary for the characterization of GGO nodules on HRCT was 120 mA, although their identification was possible at currents of >30 mA.     

Computer-aided diagnosis of lung cancer: definition and detection of ground-glass opacity type of nodules by high-resolution computed tomography

Purpose  The ground-glass opacity (GGO) of lung cancer is identified only subjectively on computed tomography (CT) images as no quantitative characteristic has been defined for GGOs. We sought to define GGOs quantitatively and to differentiate between GGOs and solid-type lung cancers semiautomatically with a computer-aided diagnosis (CAD). Methods and materials  High-resolution CT images of 100 pulmonary nodules (all peripheral lung cancers) were collected from our clinical records. Two radiologists traced the contours of nodules and distinguished GGOs from solid areas. The CT attenuation value of each area was measured. Differentiation between cancer types was assessed by a receiver-operating characteristic (ROC) analysis. Results  The mean CT attenuation of the GGO areas was −618.4 ± 212.2 HU, whereas that of solid areas was −68.1 ± 230.3 HU. CAD differentiated between solidand GGO-type lung cancers with a sensitivity of 86.0% and specificity of 96.5% when the threshold value was −370 HU. Four nodules of mixed GGOs were incorrectly classified as the solid type. CAD detected 96.3% of GGO areas when the threshold between GGO and solid areas was 194 HU. Conclusion  Objective definition of GGO area by CT attenuation is feasible. This method is useful for semiautomatic differentiation between GGOs and solid types of lung cancer.     

The relative frequencies of causes of widespread ground-glass opacity: A retrospective cohort

Purpose

The purpose of our study was to determine the relative frequencies of causes of widespread ground-glass opacity (GGO) in an unselected, consecutive patient population and to identify any associated imaging findings that can narrow or reorganize the differential.

Materials and methods

The study was approved by the center's IRB and is HIPPA compliant. Cases with widespread GGO in the radiology report were identified by searching the Radiology Information System. Medical records and CT scan examinations were reviewed for the causes of widespread GGO. Associations between a less dominant imaging finding and a particular diagnosis were analyzed with the chi square test. Our study group consisted of 234 examinations with 124 women and 110 men and a mean age of 53.7 years.

Results

A cause was established in 204 (87.2%) cases. Hydrostatic pulmonary edema was most common with 131 cases (56%). Interstitial lung diseases (ILD) were the next most common, most often hypersensitivity pneumonitis (HP) (n = 12, 5%) and connective tissue disease related ILD (n = 7, 3%). Infection accounted for 5% (12 cases). A few miscellaneous diseases accounted for 5 cases (2.1%). The combination of septal thickening and pleural effusions had a specificity of 0.91 for hydrostatic pulmonary edema (P < .001) while centrilobular nodules and air trapping had a specificity of 1.0 for HP. In 24 (10.2%) patients, increased opacification from expiration was incorrectly interpreted as representing widespread ground glass opacity.The relative frequency of disease dramatically changed according to the setting. In the inpatient setting, diffuse alveolar disease and diffuse infection accounted for all of the known diagnoses. Pulmonary edema accounted for 75% of the diagnoses and diffuse infection accounted for approximately 7%. In the outpatient setting, interstitial lung disease was the most common cause, accounting for 26 of 53 cases (49%).Regarding immunocompromised patients, hydrostatic pulmonary edema was still the most common cause (46%) with diffuse infection (24%) the next most likely diagnosis. For patients with bone marrow suppression, 80% of the cases were due to opportunistic viral infection.

Conclusion

Widespread GGO is most commonly a manifestation of hydrostatic pulmonary edema. Outpatients will most often have HP or connective tissue disease related ILD. Associated findings are helpful for the diagnosis of hydrostatic pulmonary edema and HP.     

CT fluoroscopy-guided vs. multislice CT biopsy mode-guided lung biopsies: accuracy, complications and radiation dose

Background

The aim of this retrospective study was to compare the diagnostic accuracy, the frequency of complications, the duration of the interventions and the radiation doses of CT fluoroscopy (CTF) guided biopsies of lung lesions with those of multislice CT (MS-CT) biopsy mode-guided biopsies.

Methods

Data and images from 124 consecutive patients undergoing CTF-guided lung biopsy (group A) and 132 MS-CT-biopsy mode-guided lung biopsy (group B) were reviewed. CTF-guided biopsies were performed on a Siemens Emotion 6 CT scanner with intermittent or continuous CT-fluoroscopy, MS-CT biopsy mode-guided biopsies were performed on a Siemens Emotion 16 CT scanner. All biopsies were performed with a coaxial needle technique.

Results

The two groups (A vs. B) did not differ significantly regarding sensitivity (95.5% vs. 95.9%), specificity (96.7% vs. 95.5%), negative predictive value (87.9% vs. 84%) or positive predictive value (98.8% vs. 98.9%). Pneumothorax was observed in 30.0% and 32.5% of the patients, respectively. Chest tube placement was necessary in 4% (group A) and 13% (group B) of the patients. The duration of the intervention was significantly longer in group A (median 37 min vs. 32 min, p = 0.04). The mean CT dose index (CTDI) was 422 in group A and 36.3 in group B (p < 0.001).

Conclusion

Compared to CTF-guided biopsies, chest biopsies using the MS-CT biopsy mode show dramatically lower CTDI levels. Although the diagnostic yield of the procedures do not differ significantly, biopsies using the MS-CT-biopsy mode have a three-fold higher rate of chest tube placement.     

Focal area of ground-glass opacity and ground-glass opacity predominance on thin-section CT: discrimination between neoplastic and non-neoplastic lesions

AIM: To reveal differences in thin-section computed tomography (CT) findings between lung neoplastic lesions and non-neoplastic lesions, which showed a focal area of ground-glass opacity or ground-glass opacity predominance. MATERIALS AND METHODS: A total of 82 focal areas of ground-glass opacity and ground-glass opacity predominance, consisting of 38 neoplastic and 44 non-neoplastic lesions, were assessed retrospectively regarding their thin-section CT findings. RESULTS: The frequency of wholly well-defined margin (p=0.001), spiculation (p=0.019), pleural indentation (p=0.016), air bronchograms (p=0.027), air-containing space (p=0.004) was significantly higher in neoplastic lesions than in non-neoplastic lesions. Thirty-four of 38 (89%) neoplastic lesions were well-defined in more than 50% of the circumference, of which nine had an air-containing space other than air bronchogram, whereas only one non-neoplastic lesion had these features. CONCLUSION: A focal area of ground-glass opacity or ground-glass opacity predominance with a well-defined margin and air-containing space is more likely to be a neoplasm.     

CT-guided cutting needle lung biopsy using modified coaxial technique: factors effecting risk of complications

Purpose

We present our 7-year experience with coaxial computed tomography (CT)-guided cutting needle lung biopsy and evaluate the factors affecting risk of complications.

Material and method

Between June 2000 and March 2007, we performed 225 CT-guided coaxial lung biopsies in 213 consecutive patients (161 men, 52 women). Lesion size, lesion depth, lesion location, needle-pleural angle, presence of pleural effusion, patient's position, and complications secondary to biopsy procedure (pneumothorax and bleeding) were noted. Pneumothorax was graded as mild, moderate, and severe. Bleeding complications were graded as mild, moderate, and severe.

Results

Two hundred twenty-five biopsy procedures were performed in 213 patients. The mean diameter of the lung lesion was 41.3 ± 20.1 mm. The mean distance from the peripheral margin of the lesion to the pleura was 17.3 ± 19.2 mm. After 225 procedures, there were 42 mild (18.6%), 13 moderate (5.7%), and 4 severe (1.7%) pneumothoraxes. Small hemoptysis occurred in 27 patients (12%), and mild parenchymal hemorrhage occurred in 2 patients (0.8%). The overall complication rate was 39.1%. Although, a statistically significant correlation was found between female sex, presence of emphysema, lesion depth, and pneumothorax, none of these factors had a predictive value for pneumothorax. Although, statistically significant correlations were found between female sex, lesion size, and bleeding, only lesion size had a predictive value for bleeding.

Conclusion

The most frequent and important complications of this procedure are pneumothorax and bleeding. But any factor is the predictor of pneumothorax and lesion depth is a poor predictor of bleeding complication.     

肺部纯磨玻璃结节的CT研究进展

由于医学成像技术的迅速发展,CT得到了广泛普及应用。随着肺结节检出率的提高,人们对肺小结节尤其是磨玻璃结节也有了进一步的认识。相比实性结节,磨玻璃结节虽然生长缓慢,但它的恶性率却高于实性肺结节,诊断难度大,尤其是持续存在的纯磨玻璃结节,由于缺乏特异征象,其诊断难度更高,且与早期肺癌相关性较大,故对纯磨玻璃结节的CT研究具有重要的临床价值。就纯磨玻璃结节的定义、病理特征及CT研究进展进行综述。     

CT characteristics of resolving ground-glass opacities in a lung cancer screening programme

Purpose

This study aimed at evaluating the computed tomography (CT) characteristics of resolving localized ground-glass opacities (GGOs) in a screening programme for lung cancer.

Material and methods

280 patients at high-risk for lung cancer (221 men, 59 women; mean age, 58.6 years), divided into four groups (lung cancer history (n = 83), head and neck cancer history (n = 63), symptomatic (n = 88) and asymptomatic (n = 46) cigarette smokers), were included in a prospective trial with annual low-dose CT for lung cancer screening. We retrospectively reviewed all localized GGOs, analyzed the CT characteristics on initial CT scans and changes during follow-up (median 29.1 months). Variables associated with resolution of GGOs were tested using chi-square or Mann-Whitney tests.

Results

A total of 75 GGOs were detected in 37 patients; 54.7% were present at baseline and 45.3% appeared on annual CT. During follow-up, 56.2% persisted and 43.8% disappeared. The resolving localized GGOs were significantly more often lobular GGOs (p = 0.006), polygonal in shape (p = 0.02), mixed (p = 0.003) and larger (p < 0.0001) than non-resolving localized GGOs.

Conclusion

Localized GGOs are frequent and many disappeared on follow-up. CT characteristics of resolving GGOs show significant differences compared to persistent ones. This study emphasizes the importance of short-term CT follow-up in subjects with localized GGOs.     

Quantitative CT analysis of pulmonary pure ground-glass nodule predicts histological invasiveness

ObjectiveTo assess whether quantitative computed tomography (CT) can help predict histological invasiveness of pulmonary adenocarcinoma appearing as pure ground glass nodules (pGGNs).MethodsA total of 110 pulmonary pGGNs were retrospectively evaluated, and pathologically classified as pre-invasive lesions, minimally invasive adenocarcinoma (MIA) and invasive pulmonary adenocarcinoma (IPA). Maximum nodule diameters, largest cross-sectional areas, volumes, mean CT values, weights, and CT attenuation values at the 0th,2th,5th, 25th, 50th,75th, 95th, 98th and100th percentiles on histogram, as well as 2th to 98th, 5th to 95th, 25th to 75th,and 0th to 100thslopes, respectively, were compared among the three groups.ResultsOf the 110 pGGNs, 50, 28, and 32 were pre-invasive lesions, MIA, and IPA, respectively. Maximum nodule diameters, largest cross-sectional areas, andmass weights were significantly larger in the IPA group than in pre-invasive lesions. The 95th, 98th, 100th percentiles, and 2th to 98th, 25th to 75th, and 0th to 100thslopes were significantly different between pre-invasive lesions and MIA or IPA. Logistic regression analysis showed that the maximum nodule diameter (OR = 1.21, 95%CI: 1.071–1.366, p < 0.01) and 100th percentile on histogram (OR = 1.02, 95%CI: 1.009–1.032, p < 0.001) independently predicted histological invasiveness.ConclusionsQuantitative analysis of CT imaging can predict histological invasiveness of pGGNs, especiallythe maximum nodule diameter and 100th percentile on CT number histogram; this can instruct the long-term follow-up and selective surgical management.     

CT定位经皮肺穿刺活检术对周围型肺占位病变诊断的临床应用

目的 探讨CT定位经皮肺穿刺活检术用于肺周围型占位病变诊断的意义。方法 采用美国Cook公司的PREMED716、18、19、20G软组织活检针或不带针芯的细针，长度分别为8、10、12、16cm，外径分别为0．7、0．8、0．9mm，多数选用0．8mm，在PICKER IQXTRACT机导向下穿刺65例肺周围型占位病变。结果 65例经皮肺穿刺活检，经病理检查证实62例，其中原发性恶性肿瘤56例，结核3例，炎性假瘤2例，转移性癌1例，3例未能得到明确诊断，组织学诊断率为95．4％，术后4例并发少量气胸，2例出现血丝痰，均未作特殊处理。结论 CT定位经皮肺穿刺活检是比较安全、准确率很高的诊断手段，且在经济上也是可行的技术，可在有条件的单位广泛应用。     

Percutaneous needle aspiration biopsy (PCNAB) of lung lesions: 5 years results with focusing on repeat PCNAB

Purpose

To evaluate 5 years results of percutaneous needle aspiration biopsy (PCNAB) for lung lesions and usefulness of the reaspiration or rebiopsy of lung lesions (repeat PCNAB).

Materials and methods

Six hundred and fifteen cases of PCNAB (591 initial PCNAB and 24 repeat PCNAB) performed under the CT or fluoroscopy guidance in 591 patients was enrolled. The procedure was done using an automated biopsy gun with a 20-G needle (519 cases) or a 20-G aspiration needle (96 cases). The pathologic results, type and rate of complications in the initial and repeat PCNAB were evaluated. The pathologic agreement rate between the initial and repeat PCNAB, and reasons of the repeat PCNAB were also evaluated.

Results

Of the 615 PCNAB cases, 345 cases yielded tumors and 270 cases yielded non-tumorous lesions. Of the tumorous lesions, 307 cases were primary lung malignancies, 34 cases were metastases, and 4 were benign tumors. The repeat PCNAB rate was 4.1% (24/591). There was no statistically significant difference between automated gun biopsy and needle aspiration as a biopsy tool for calling repeat PCNAB (p = 0.4034). The causes for a repeat PCNAB were inconclusive (n = 14) and unexpected pathologic results (n = 10). Of the 14 pathologically inconclusive cases on initial PCNAB, 9 cases revealed malignancy after the repeat PCNAB. Of the 10 cases with unexpected pathologic results on initial PCNAB, 3 cases yielded different pathologic results on repeat PCNAB from initial PCNAB. The cumulative complication rate of PCNAB was 11.4% (70/615).

Conclusion

PCNAB was useful for the diagnosis of pulmonary lesions. Repeat PCNAB might be helpful for the exact diagnosis of lung lesions where initial PCNAB yields inconclusive or unexpected pathologic results.     

低剂量技术降低CT引导下经皮肺切割活检吸收剂量的临床研究

目的 探讨临床应用低剂量技术降低CT引导下经皮肺穿刺自动切割活检(ACNB)辐射剂量的可行性。方法 412例ACNB中146例(A组)采用传统方法引导,266例(B组)采用低剂量技术引导,按图像颗粒均匀性、解剖结构细节、界面清晰度和有无伪影等评定图像质量,比较2组穿刺活检准确率、操作时间及辐射剂量,并探讨CT引导中降低辐射剂量的方法。结果 B组图像解剖结构细节分辨率降低,但不影响穿刺成功率。A、B组穿刺准确率分别为95.9%、95.1%,操作时间为(16±2.2)、(15.9±2.0)min,组间差异均无统计学意义。A、B组有效剂量为(1.74±0.7)及(0.59±0.14)mSv,B组有效剂量降低66%,差异有统计学意义(t=19.3415,P(0.05)。结论 CT引导下经皮肺穿刺活检是诊断和鉴别肺部病变的重要方法,低剂量扫描、缩小扫描范围及减少扫描次数能显著降低受检者X线辐射剂量,但不影响诊断效果。     

CT引导肺穿刺活检诊断周围型肺鳞癌的价值

目的:探讨应用CT引导肺穿刺活检术诊断周围型肺鳞癌的价值。方法:对CT引导肺部病变穿刺活检术的31例病例进行回顾性分析。结果:本组病例中,周围型肺鳞癌CT表现为病灶周边强化伴其内不同程度坏死27例,空洞型病灶4例。CT引导肺部病变穿刺活检病理诊断鳞癌16例,中分化鳞癌14例,发现癌变鳞状上皮1例。结论:研究表明应用CT引导肺穿刺活检术对周围型肺鳞癌病例有重要的诊断价值。     

CT fluoroscopy guided transpleural cutting needle biopsy of small (≤2.5 cm) subpleural pulmonary nodules

Purpose

Small subpleural pulmonary lesions are difficult to biopsy. While the direct, short needle path has been reported to have a lower rate of pneumothorax, the indirect path provides a higher diagnostic yield. Therefore, we tried to optimize the needle pathway and minimize the iatrogenic pneumothorax risk by evaluating a CT fluoroscopy guided direct approach to biopsy subpleural lesions.

Material and methods

Between 01/2005 and 01/2007, CT fluoroscopy guided core biopsies were performed in 24 patients. Using our technique, the tip of the guide needle remains outside the visceral pleura (17 G coaxial guide needle, 18 G Biopsy-gun, 15 or 22 mm needle path). The position of the lesion relative to the needle tip can be optimized using CT fluoroscopy by adjusting the breathing position of the patient. The Biopty gun is fired with the needle tip still outside the pleural space. Cytological smears are analyzed by a cytopathologist on-site, and biopsies are repeated as indicated with the coaxial needle still outside the pleura.

Results

Median nodule size was 1.6 cm (0.7-2.3 cm). A definitive diagnosis was obtained in 22 patients by histology and/or cytology. In one patient, only necrotic material could be obtained. In another patient, the intervention had to be aborted as the dyspnoic patient could not follow breathing instructions. An asymptomatic pneumothorax was present in seven patients; chest tube placement was not required.

Conclusion

The presented biopsy approach has a high diagnostic yield and is especially advantageous for biopsies of small subpleural lesions in the lower lobes.     

CT-guided transthoracic cutting needle biopsy of intrathoracic lesions: comparison between coaxial and single needle technique

Purpose

To evaluate the complication rates and diagnostic accuracy of two different CT-guided transthoracic cutting needle biopsy techniques: coaxial method and single needle method.

Methods

This study involved 198 consecutive subjects with 198 intrathoracic lesions. The first 98 consecutive subjects received a single needle cutting technique and the next 100 consecutive subjects received a coaxial technique. Both groups were compared in relation the diagnostic accuracy and complication rates.

Results

No significant difference was found between the two groups concerning patient characteristics, lesions and procedure variables. There was a borderline statistical difference in the incidence of pneumothorax at within 24-h post biopsy between patients in the single needle group (5%) and the coaxial group (13%) (P = 0.053). Little difference was found in the pneumothorax rate at immediately post biopsy between the two groups, which was 28% in the single needle group and 31% in the coaxial group. There was no significant difference in the hemoptysis rate between the two groups, which was 9.2% in the single needle group and 11% in the coaxial group. Both techniques yielded an overall diagnostic accuracy of 98% for malignant lesions with similar sensitivity (single needle: 96.9% vs. coaxial: 96.4%) and specificity (single needle: 100% vs. coaxial: 100%).

Conclusion

There is little difference in the pneumothorax rates and bleeding complications between patients who either received a single needle or a coaxial transthoracic cutting biopsy. Both techniques produce an overall diagnostic accuracy of 98% for malignant lesions.     

CT引导下经皮肺穿刺活检对周围型肺部病变的诊断价值

目的探讨CT引导下经皮肺穿刺活检对周围型肺部病变的诊断价值及其安全性。方法对58例周围型肺部病变的患者,在CT引导下行经皮肺穿刺活检。结果 58例患者中穿刺标本经组织病理学检查确诊病例48例,确诊率为82.8%,其中恶性肿瘤32例,良性病变16例。术后出现有症状并发症7例,其中咯血2例,气胸4例,高热伴脓胸1例,总发生率为12.1%。结论 CT引导下经皮肺穿刺活检定位准确,成功率高,安全可靠,在周围型肺部病变诊断中具有较高的应用价值。     

Predictive CT findings of malignancy in ground-glass nodules on thin-section chest CT: the effects on radiologist performance

Our purpose was to identify thin-section chest computed tomography (CT) findings of malignancy other than the presence of a solid portion within ground-glass nodules (GGNs) and to evaluate whether the radiologists’ performance in determining malignancy can be enhanced with this information. The predictive CT findings of malignancy extracted from the CT findings of 80 GGNs (47 malignant, 33 benign) were a size of >8 mm [odds ratio (OR), 10.930; P = 0.045] and a lobulated border (OR, 13.769; P = 0.016) for pure GGNs and a lobulated border (OR, 10.200; P = 0.024) for mixed GGNs. Four chest radiologists and five radiology residents participated in the observer performance study with CT of 130 GGNs (67 malignant, 63 benign). Receiver-operating characteristic (ROC) analysis was used to compare radiologists’ performances before and after providing these predictive findings. For pure GGNs, mean areas under the curve (A_z) of all readers without and with CT predictive information were significantly different (0.621 ± 0.052 and 0.766 ± 0.055, P < 0.05). For mixed GGNs, the A_z values achieved without and with predictive information were not significantly different (0.727 ± 0.064 and 0.764 ± 0.056, P > 0.05). Information about lesion size and morphological characteristics can enhance radiologists’ performance in determining malignancy of pure GGNs.     

CT imaging in acute pulmonary embolism: diagnostic strategies

Computed tomography pulmonary angiography (CTA) has increasingly become accepted as a widely available, safe, cost-effective, and accurate method for a quick and comprehensive diagnosis of acute pulmonary embolism (PE). Pulmonary catheter angiography is still considered the gold standard and final imaging method in many diagnostic algorithms. However, spiral CTA has become established as the first imaging test in clinical routine due to its high negative predictive value for clinically relevant PE. Despite the direct visualization of clot material, depiction of cardiac and pulmonary function in combination with the quantification of pulmonary obstruction helps to grade the severity of PE for further risk stratification and to monitor the effect of thrombolytic therapy. Because PE and deep venous thrombosis are two different aspects of the same disease, additional indirect CT venography may be a valuable addition to the initial diagnostic algorithm—if this was positive for PE—and demonstration of the extent and localization of deep venous thrombosis has an impact on clinical management. Additional and alternate diagnoses add to the usefulness of this method. Using advanced multislice spiral CT technology, some practitioners have advocated CTA as the sole imaging tool for routine clinical assessment in suspected acute PE. This will simplify standards of practice in the near future.