Jeong Min Ko

Benign tumors of the tracheobronchial tree: CT-pathologic correlation.

OBJECTIVE The purpose of this essay is to illustrate the CT findings of variable benign tumors of the tracheobronchial tree and to correlate the CT and pathologic findings in 17 patients. CONCLUSION The tracheal tumors were eccentric, well-defined, polypoid masses in all cases. The endobronchial tumors were masses confined within the bronchus in all cases, and atelectasis or pneumonia of the distal parenchyma was frequently associated. Of the six hamartomas, one was a fatty mass, and two were nodules with calcification. The others were soft-tissue-density nodules. The lipomas manifested as fat density on CT scans in both cases. The other benign tumors were low-attenuating, soft-tissue-density masses without characteristic findings on CT scans.

Pulmonary Changes of Pleural TB: Up-to-Date CT Imaging

BACKGROUND The objective of this study was to evaluate pulmonary abnormalities of pleural TB by CT scanning and to determine CT scan findings for the development of the paradoxical response (PR). METHODS CT scans were performed for 349 patients with pleural TB (between 2008 and 2013). We excluded 34 patients with coexisting pulmonary disease (n 5 13) or a totally collapsed lung (n 5 21). We analyzed CT scans focusing on pulmonary abnormalities such as the presence of consolidation, cavitation, interlobular septal thickening, and micronodules and their distribution. In addition, we recorded the development of PR during follow-up and statistically analyzed differences in clinical and CT scan findings between patients with and without PR. RESULTS A total of 270 of 315 patients (86%) had pulmonary abnormalities. Common CT scan findings were micronodules (n 5 209 [77%]), interlobular septal thickening (n 5 202 [75%]),and consolidation (n 5 120 [44%]). Cavitation was seen in 49 patients (18%). Among 209 with micronodules, the nodules were in the subpleural region (n 5 146 [70%]), peribronchovascular interstitium (n 5 113 [54%]), and centrilobular region (n 5 64 [31%]). PR occurred in 81 patients(26%), and patients with PR tended to be young, male, and without underlying disease ( P , .05 by t test, Pearson x 2 test). Subpleural micronodules were more common in patients with PR than in those without PR (Pearson x 2 , P 5 .025). CONCLUSIONS Pulmonary abnormalities are very common in pleural TB. Th e most common CT scan findings were micronodules in the subpleural and peribronchovascular interstitium and interlobular septal thickening, suggesting the lymphatic spread of TB. In addition, PR is not rare in patients with pleural TB, especially in young, previously healthy, male patients who show subpleural nodules on initial CT scans.

Complications of pneumoconiosis: Radiologic overview

A wide spectrum of pulmonary complications occurs in patients with pneumoconiosis. Those complications include chronic obstructive pulmonary disease, hemoptysis, pneumothorax, pleural disease, tuberculosis, autoimmune disease, anthracofibrosis, chronic interstitial pneumonia, and malignancy. Generally, imaging workup starts with plain chest radiography. However, sometimes, plain radiography has limited role in the diagnosis of pulmonary complications of pneumoconiosis because of overlapping pneumoconiotic infiltration. Computed tomography (CT), ultrasonography (US), and magnetic resonance imaging (MRI) are potentially helpful for the detection of pulmonary complications in patients with pneumoconiosis. CT, with its excellent contrast resolution, is more sensitive and specific method than plain radiograph in the evaluation of pulmonary abnormalities. CT is useful in detecting lung parenchymal abnormalities caused by infection, anthracofibrosis, and chronic interstitial pneumonia. Also, CT is valuable in distinguishing localized pneumothorax from bullae and aiding the identification of multiloculated effusions. US can be used in detection of complicated pleural effusions and guidance of the thoracentesis procedure. MRI is useful for differentiating between progressive massive fibrosis and lung cancer. Radiologists need to be familiar with the radiologic and clinical manifestations of, as well as diagnostic approaches to, complications associated with pneumoconiosis. Knowledge of the various imaging features of pulmonary complications of pneumoconiosis can enhance early diagnosis and improve the chance to cure.

Clinicoradiologic Evidence of Pulmonary Lymphatic Spread in Adult Patients With Tuberculosis

OBJECTIVE The purpose of this study is to evaluate the prevalence and clinicoradiologic characteristics of pulmonary tuberculosis with lymphatic involvement. MATERIALS AND METHODS A total of 126 adults with active tuberculosis who underwent CT were enrolled. A retrospective investigation of CT images focused on the presence of perilymphatic micronodules, as well as other CT features of active tuberculosis. We selected two groups of patients with micronodules according to distribution (perilymphatic vs centrilobular). We compared clinical and CT findings between the two groups. RESULTS Fifteen patients were excluded because of coexisting pulmonary disease. Among 111 patients, the prevalence of perilymphatic micronodules, galaxy or cluster signs, and interlobular septal thickening was 64 (58%), 18 (16%), and 30 (27%), respectively. Of 106 patients with micronodules, 37 and 40 were classified into the perilymphatic and centrilobular groups, respectively. Compared with the centrilobular group, the perilymphatic group had statistically significantly lower frequencies of positive acid-fast bacilli smears (32% vs 70%), consolidation (70% vs 98%), and cavitation (30% vs 60%). However, frequencies of interlobular septal thickening (41% vs 18%), galaxy or cluster signs (30% vs 0%), and pleural effusion (43% vs 20%) were statistically significantly higher in the perilymphatic group. CONCLUSION CT findings representing pulmonary perilymphatic involvement are relatively common in adults with tuberculosis. These findings may represent lymphatic spread of tuberculosis and provide an explanation for the unusual CT features of pulmonary tuberculosis mimicking sarcoidosis and the low detection of Mycobacterium tuberculosis in patients with micronodules.

Bronchiectasis in active tuberculosis

Background Bronchiectasis in tuberculosis (TB) is usually considered chronic traction bronchiectasis associated with healed scars. However, bronchiectasis can occasionally be seen in active TB. Purpose To evaluate prevalence, appearance, and changes of bronchiectasis associated with active TB on computed tomography (CT). Material and Methods A total of 391 patients with active TB who had undergone CT scans at the time of diagnosis were included in the study. Active TB was diagnosed when the sputum or the sample obtained by bronchoalveolar lavage tested positive using an acid-fast bacillus (AFB) smear test, polymerase chain reaction (PCR) test, or an AFB culture. The CT scans were reviewed focusing on bronchiectasis within consolidations or nodules. Cases with bronchiectasis beyond the consolidation or nodules were excluded from the study to exclude pre-existing traction bronchiectasis. The prevalence and appearance (cylindrical, varicose, cystic, and presence of focal erosion) of bronchiectasis and its time-dependent changes were analyzed. In addition, the presence of the feeding bronchus sign was checked. Here, the feeding bronchus sign was defined as a CT finding where the cavity communicates with the dilated airway. Results In 100 (25%) of the 391 patients, bronchiectasis was present within consolidations or nodules on CT. The shape of the bronchiectasis was cylindrical in all patients and focal erosions were revealed in 75 patients (75%). Nine patients had both cylindrical and varicose forms of the bronchiectasis. The feeding bronchus sign was observed in 42 patients (42%). Follow-up CT was performed on 19 of 100 patients. The bronchiectasis had progressed in 11 patients (58%), improved in four patients (21%), remained unchanged in one patient (5%), and could not be determined in the remaining three patients (16%). In nine patients, CT images prior to diagnosis were available, and in all these cases, bronchiectasis was newly developed. Conclusion Bronchiectasis can be seen within active inflammation in one-fourth of active TB on CT. In association with active inflammation, bronchiectasis is mostly cylindrical with focal erosions, occasionally accompanied by the feeding bronchus sign.

Dynamic CT and MRA findings of a case of portopulmonary venous anastomosis (PPVA) in a patient with portal hypertension: a case report and review of the literature

Portopulmonary venous anastomosis (PPVA), which has been rarely reported in conventional CT and MR studies, is an unusual collateral pathway in patients with portal hypertension. It has clinical implications related to right-to-left shunt that are different from the clinical implications related to other more usual portosystemic shunts in portal hypertensive patients. Here, we report the dynamic CT and MRA findings of a case of PPVA in a patient with portal hypertension, directly demonstrating the shunt flow from the paraesophageal varix to the left atrium via the right inferior pulmonary vein.

The relation between CT findings and sputum microbiology studies in active pulmonary tuberculosis

PURPOSE To evaluate whether CT findings suggesting active pulmonary tuberculosis correlate with sputum microbiological studies, and to determine whether CT could predict infectivity. MATERIALS AND METHODS Total 108 patients with active pulmonary tuberculosis were enrolled. We reviewed CT findings and sputum microbiological studies. Then, we analyzed the statistical difference in CT findings between the positive and negative groups of each sputum microbiological study (AFB smear, PCR, and culture). Also, we divided the patients into five groups according to sputum AFB smear grade and analyzed linear trends of CT findings between the five groups. RESULTS Both frequencies and extents of centrilobular micronodules (63% vs 38%, p=0.011 for frequency; 1.6 ± 1.6 vs 0.6 ± 1.1, p=0.001 for extent), tree-in-bud opacities (63% vs 33%, p=0.002; 1.6 ± 1.6 vs 0.5 ± 0.9, p<0.001, respectively), consolidation (98% vs 81%, p=0.003; 2.7 ± 1.5 vs 1.3 ± 1.1, p<0.001, respectively), and cavitation (86% vs 33%, p<0.001; 1.5 ± 1.2 vs 0.4 ± 0.7, p<0.001, respectively), were significantly increased in the sputum AFB-positive group than in the negative group. These four CT findings were increase in frequency and extent in the sputum PCR-positive group with or without statistical significance. They did not show significant differences between the sputum culture-positive and negative groups. As the AFB smear grade increased, frequencies and extents of centrilobular micronodules, tree-in-bud, consolidation, and cavitation also increased. CONCLUSION CT features representing active tuberculosis-centrilobular nodules, tree-in-bud, consolidation, and, cavitation-strongly correlate with the positivity and grading of AFB smear.

CT-guided core biopsy of malignant lung lesions: how many needle passes are needed?

The study aims to determine the number of needle pass in the CT‐guided core needle biopsy (CNB) in making a diagnosis of pulmonary malignancy.

Depth of Pleural Effusion in Thoracentesis: Comparison of Lateral, Posterolateral and Posterior Approaches in the Supine Position

Background In patients who have difficulty sitting, thoracentesis is attempted in a supine position via lateral approach. Recently, a new table has been designed for supine thoracentesis. This table has gaps that allow access to the posterolateral and posterior hemithorax. Objectives To compare important safety-related parameters between lateral, posterolateral, and posterior approaches in supine thoracentesis. Materials and Methods First, two cadavers were placed supine on a table featuring gaps allowing access to the posterolateral and posterior hemithorax. Water was administered with sonographic measurement of the depth of pleural effusion (DPE) at the mid-axillary and posterior axillary line. Second, CT images were analyzed in 25 consecutive patients (32 free-shifting, moderate-to-large effusions; mean, 668 (146 - 2020 mL). DPE, craniocaudal distance that effusion can be visualized (CCD), and presence of passive atelectasis at each of the lateral, posterolateral, and posterior routes was assessed. Results In each cadaver, DPE in the posterolateral route was greater than that in the lateral route (P = 0.002, P < 0.001). The amount of pleural fluid enough to spread DPE to higher than 1 cm at the posterior axillary line was less than half the amount at the mid-axillary line (500 mL vs. 1,100 mL; 800 mL vs. 1700 mL). CT showed that the DPEs and CCDs of posterolateral and posterior routes were greater than those of the lateral route (P < 0.001). In thirteen effusions (40.6%), DPE was greater than 1 cm in both posterolateral and posterior routes but less than 1 cm in the lateral route. Frequencies of passive atelectasis in posterolateral and posterior routes (81.3% and 90.6%) were higher (P < 0.001) than that in the lateral route (28.1%). Conclusion Safety-related parameters of posterolateral and posterior approaches in supine thoracentesis are far better than that of the conventional lateral approach.

Main Pulmonary Artery Dilatation in Patients with Anthracofibrosis

This study assessed main pulmonary artery diameter of patients with anthracofibrosis. Patients with anthracofibrosis and CT scans were evaluated after exclusion of patients with co-existing disease. We measured the diameter of the main pulmonary artery (PAD) and ascending aorta (AD) and calculated the pulmonary artery to aorta ratio (APR). The upper reference limit for comparison of PAD was 29 mm. Cut-off values for PAD and APR indicating pulmonary hypertension were 33 mm and 1. We correlated the CT parameters with echocardiographic results. Total 51 patients were included in the analysis. The mean PAD, AD, and APR were 33 mm, 38 mm, and 0.87 respectively. The PAD was larger than the upper reference limit, 29 mm (P<0.001). The PAD was >33 mm in 30 (65%) and the APR was >1 in 9 patients (18%). Of 21 patients with echocardiography, 11 (52%) were found to have pulmonary hypertension. There was no statistical difference in the diagnosis of pulmonary hypertension between echocardiography and CT (P=1.000). In conclusion, main pulmonary artery is dilated in patients with anthracofibrosis more than in the healthy population. Graphical Abstract