Pulmonary high-resolution computed tomography findings in nephropathia epidemica

Purpose

To evaluate lung high-resolution computed tomography (HRCT) findings in patients with Puumala hantavirus-induced nephropathia epidemica (NE), and to determine if these findings correspond to chest radiograph findings.

Materials and methods

HRCT findings and clinical course were studied in 13 hospital-treated NE patients. Chest radiograph findings were studied in 12 of them.

Results

Twelve patients (92%) showed lung parenchymal abnormalities in HRCT, while only 8 had changes in their chest radiography. Atelectasis, pleural effusion, intralobular and interlobular septal thickening were the most common HRCT findings. Ground-glass opacification (GGO) was seen in 4 and hilar and mediastinal lymphadenopathy in 3 patients. Atelectasis and pleural effusion were also mostly seen in chest radiographs, other findings only in HRCT.

Conclusion

Almost every NE patient showed lung parenchymal abnormalities in HRCT. The most common findings of lung involvement in NE can be defined as accumulation of pleural fluid and atelectasis and intralobular and interlobular septal thickening, most profusely in the lower parts of the lung. As a novel finding, lymphadenopathy was seen in a minority, probably related to capillary leakage and overall fluid overload. Pleural effusion is not the prominent feature in other viral pneumonias, whereas intralobular and interlobular septal thickening are characteristic of other viral pulmonary infections as well. Lung parenchymal findings in HRCT can thus be taken not to be disease-specific in NE and HRCT is useful only for scientific purposes.     

Cytomegalovirus Pneumonia: High-Resolution CT Findings in Ten Non-AIDS Immunocompromised Patients

Objective

To describe the HRCT findings of cytomegalovirus (CMV) pneumonia in non-AIDS immunocompromised patients.

Materials and Methods

This retrospective study involved the ten all non-AIDS immunocompromised patients with biopsy-proven CMV pneumonia and without other pulmonary infection encountered at our Medical Center between January 1997 and May 1999. HRCT scans were retrospectively analysed by two chest radiologists and decisions regarding the findings were reached by consensus.

Results

The most frequent CT pattern was ground-glass opacity, seen in all patients, with bilateral patchy (n = 8) and diffuse (n = 2) distribution. Other findings included poorly-defined small nodules (n = 9) and consolidation (n = 7). There was no zonal predominance. The small nodules, bilateral in eight cases and unilateral in one, were all located in the centrilobular region. Consolidation (n = 7), with patchy distribution, was bilateral in five of seven patients (71%). Pleural effusion and bilateral areas of thickened interlobular septa were seen in six patients (60%).

Conclusion

CMV pneumonia in non-AIDS immunocompromised patients appears on HRCT scans as bilateral mixed areas of ground-glass opacity, poorly-defined centrilobular small nodules, and consolidation. Interlobular septal thickening and pleural effusion are frequently associated.     

Comparison of initial high resolution computed tomography features in viral pneumonia between metapneumovirus infection and severe acute respiratory syndrome

Objective

To review and compare initial high resolution computed tomography (HRCT) findings in patients with metapneumovirus pneumonia and severe acute respiratory syndrome (SARS-Coronovirus).

Materials and methods

4 cases of metapneumovirus pneumonia (mean age of 52.3 years) in an institutional outbreak (Castle Peak Hospital) in 2008 and 38 cases of SARS-coronovirus (mean age of 39.6 years) admitted to Tuen Mun hospital during an epidemic outbreak in 2003 were included. HRCT findings of the lungs for all patients were retrospectively reviewed by two independent radiologists.

Results

In the metapneumovirus group, common HRCT features were ground glass opacities (100%), consolidation (100%), parenchymal band (100%), bronchiectasis (75%). Crazy paving pattern was absent. They were predominantly subpleural and basal in location and bilateral involvement was observed in 50% of patients. In the SARS group, common HRCT features were ground glass opacities (92.1%), interlobular septal thickening (86.8%), crazy paving pattern (73.7%) and consolidation (68%). Bronchiectasis was not seen. Majority of patient demonstrated segmental or lobar in distribution and bilateral involvement was observed in 44.7% of patients. Pleural effusion and lymphadenopathy were of consistent rare features in both groups.

Conclusion

Ground glass opacities, interlobular septal thickening and consolidations were consistent HRCT manifestations in both metapneumovirus infection and SARS. The presence of bronchiectasis (0% in SARS) may point towards metapneumovirus while crazy paving pattern is more suggestive of SARS.     

"Crazy-Paving" Patterns on High-Resolution CT Scans in Patients with Pulmonary Complications after Hematopoietic Stem Cell Transplantation

Objective

To describe the pulmonary complications following hematopoietic stem cell transplantation (HSCT) that can present with a "crazy-paving" pattern in high-resolution CT scans.

Materials and Methods

Retrospective review of medical records from 2,537 patients who underwent HSCT. The "crazy-paving" pattern consists of interlobular and intralobular septal thickening superimposed on an area of ground-glass attenuation on high-resolution CT scans. The CT scans were retrospectively reviewed by two radiologists, who reached final decisions by consensus.

Results

We identified 10 cases (2.02%), seven male and three female, with pulmonary complications following HSCT that presented with the "crazy-paving" pattern. Seven (70%) patients had infectious pneumonia (adenovirus, herpes simplex, influenza virus, cytomegalovirus, respiratory syncytial virus, and toxoplasmosis), and three patients presented with non-infectious complications (idiopathic pneumonia syndrome and acute pulmonary edema). The "crazy-paving" pattern was bilateral in all cases, with diffuse distribution in nine patients (90%), predominantly in the middle and inferior lung regions in seven patients (70%), and involving the anterior and posterior regions of the lungs in nine patients (90%).

Conclusion

The "crazy-paving" pattern is rare in HSCT recipients with pulmonary complications and is associated with infectious complications more commonly than non-infectious conditions.     

高分辨率CT上肺细网状影的形态分析及病理基础

目的 探讨HRCT上肺细网状影的形态学表现及病理基础.方法 搜集本院2004年8月至2007年2月107例在HRCT上有细网状影患者临床病例资料进行细网状影形态学及动态变化分析研究.搜集24例病理证实充气标本进行影像与病理的对照研究.用X~2检验进行统计学分析.结果 细网状影网间隙直径一般≤3 mm,为圆形或不规则形,网间隙内为肺实质密度.网壁光滑或粗糙,厚度约≤1 mm.107例临床患者细网状影的伴随征象有磨玻璃密度影(GGO)(68.2%,73例)、铺路石征(23.4%,25例)、小叶间隔增厚(84.1%,90例)、肺气肿(32.7%,35例)、界面征(58.9%,63例)、牵拉性支气管扩张(41.1%,44例)及蜂窝征(26.2%,28例).纤维化患者与肺炎患者在蜂窝、牵拉性支气管扩张、小叶间隔增厚、界面征及铺路石征方面差异有统计学意义(P均＜0.01).肺炎大片状GGO合并细网状影形成铺路石征;癌性淋巴管炎细网状影合并小叶间隔增厚,并见串珠样结节影;特发性肺纤维化(IPF)细网状影多镶嵌在蜂窝之间;结缔组织病(CTD)并肺间质纤维化早期以细网状影为主,蜂窝影少见,及时治疗后可完全或部分吸收;慢性支气管炎细网状影合并肺气肿.58例随访患者中26例网状影增加,22例网状影减少或消失,10例无变化.24例肺标本细网状影病理基础主要为小叶内间质纤维增生、炎性细胞及肿瘤细胞浸润、渗出液充填、煤尘沉积等.结论 细网状影是由小叶内间质增厚形成,可由炎症、间质增生、肺纤维化和肿瘤引起,有助于提示这些疾病的存在,诊断价值需结合其他CT表现及动态变化.     

Malignant Pure Pulmonary Ground-Glass Opacity Nodules: Prognostic Implications

Objective

This study was designed to evaluate follow-up results in terms of patient prognosis for malignant pulmonary nodules depicted as pure ground-glass opacity (GGO) lesion observed at high-resolution CT (HRCT).

Materials and Methods

Surgical removal for malignant GGO nodules was accomplished in 58 patients (26 men, 32 women; mean age, 57 years; age range, 29-78 years). Patient prognoses were assessed by patient clinical status and the presence of changes in nodule size determined after a follow-up HRCT examination. Differences in patient prognoses were compared for nodule number, size, surgical method, change in size before surgical removal, and histopathological diagnosis by use of Fisher''s exact test and Pearson''s chi-squared test.

Results

Of the 58 patients, 40 patients (69%) were confirmed to have a bronchioloalveolar carcinoma (BAC) and 18 patients (31%) were confirmed to have an adenocarcinoma with a predominant BAC component. Irrespective of nodule size, number, treatment method, change in size before surgical removal and histopathological diagnosis, neither local recurrence nor a metastasis occurred in any of these patients as determined at a follow-up period of 24 months (range; 12-65 months). Of 14 patients with multiple GGO nodules, all of the nodules were resected without recurrence in six patients. In the remaining eight patients, the remaining nodules showed no change in size in seven cases and a decrease in size in one case as determined after a follow-up CT examination.

Conclusion

Prognoses in patients with pure GGO malignant pulmonary nodules are excellent, and not significantly different in terms of nodule number, size, surgical method, presence of size change before surgical removal and histopathological diagnosis.     

Paracoccidioidomycosis: High-resolution computed tomography-pathologic correlation

Objective

The purpose of this study was to describe the high-resolution computed tomography (HRCT) features of pulmonary paracoccidioidomycosis and to correlate them with pathologic findings.

Methods

The study included 23 adult patients with pulmonary paracoccidioidomycosis. All patients had undergone HRCT, and the images were retrospectively analyzed by two chest radiologists, who reached decisions by consensus. An experienced lung pathologist reviewed all pathological specimens. The HRCT findings were correlated with histopathologic data.

Results

The predominant HRCT findings included areas of ground-glass opacities, nodules, interlobular septal thickening, airspace consolidation, cavitation, and fibrosis. The main pathological features consisted of alveolar and interlobular septal inflammatory infiltration, granulomas, alveolar exudate, cavitation secondary to necrosis, and fibrosis.

Conclusion

Paracoccidioidomycosis can present different tomography patterns, which can involve both the interstitium and the airspace. These abnormalities can be pathologically correlated with inflammatory infiltration, granulomatous reaction, and fibrosis.     

Comparative study of clinical, pathological and HRCT findings of primary alveolar proteinosis and silicoproteinosis

Objective

To compare the clinical, high-resolution computed tomography (HRCT) and pathological findings of primary alveolar proteinosis (PAP) and silicoproteinosis.

Material and methods

The study included 15 patients with PAP (6 women, 9 men, mean age 31 years) and 13 with silicoproteinosis (13 men, mean age 29.5 years). PAP was diagnosed by lung biopsy in 13 and bronchoalveolar lavage in two patients and silicoproteinosis by bronchoalveolar lavage in 10 and autopsy in three cases. HRCT images were reviewed by two chest radiologists with consensus for the presence, extent and distribution of ground-glass opacities, septal thickening, consolidation and nodules. Radiological–pathological correlation was performed by one radiologist and one chest pathologist.

Results

Seven (46%) patients with PAP were asymptomatic; the remainder presented slowly progressive dyspnea and dry cough. All silicoproteinosis patients had dry cough and rapidly progressive dyspnea. The most common HRCT finding on PAP was the crazy-paving pattern (93%). All cases had areas of geographic sparing in the affected lung. The most common finding in silicoproteinosis (92%) was dependent consolidation with calcification in 83%. Centrilobular nodules were common (85%). On pathology, both diseases demonstrated intra-alveolar accumulation of PAS material, thickening of interlobular septae and alveolar walls and no evidence of fibrosis. A few silica particles were seen in silicoproteinosis.

Conclusion

Despite the pathological similarities, PAP and silicoproteinosis have distinct clinical and imaging features and prognosis. Bilateral crazy-paving pattern with areas of geographic sparing is characteristic for PAP. Silicoproteinosis presents with bilateral dependent consolidation often with areas of calcification. The crazy-paving pattern is not seen in silicoproteinosis.     

Can acute interstitial pneumonia be differentiated from bronchiolitis obliterans organizing pneumonia by high-resolution CT?

PURPOSE: In the early stages, clinical and chest radiographic findings of acute interstitial pneumonia (AIP) are often similar to those of bronchiolitis obliterans organizing pneumonia (BOOP). However, patients with AIP have a poor prognosis, while those with BOOP can achieve a complete recovery after corticosteroid therapy. The objective of this study was to identify differences in high-resolution CT (HRCT) findings between the two diseases. METHODS: The study included 27 patients with AIP and 14 with BOOP who were histologically diagnosed [open-lung biopsy (n=7), autopsy (n=17), transbronchial lung biopsy (n=17)]. The frequency and distribution of various HRCT findings for each disease were retrospectively evaluated. RESULTS: Traction bronchiectasis, interlobular septal thickening, and intralobular reticular opacities were significantly more prevalent in AIP (92.6%, 85.2%, and 59.3%, respectively) than in BOOP (42.9%, 35.7%, and 14.3%, respectively) (p<0.01). Parenchymal nodules and peripheral distribution were more prevalent in BOOP (28.6% and 57.1%, respectively) than in AIP (7.4% and 14.8%, respectively) (p<0.01). Areas with ground-glass attenuation, air-space consolidation, and architectural distortion were common in both AIP and BOOP. CONCLUSION: For a differential diagnosis of AIP and BOOP, special attention should be given to the following HRCT findings: traction bronchiectasis, interlobular septal thickening, intralobular reticular opacities, parenchymal nodules, pleural effusion, and peripheral zone predominance.     

Asbestosis: high-resolution CT-pathologic correlation

High-resolution computed tomography (HRCT) was performed in seven inflated and fixed postmortem lungs from seven asbestos-exposed patients with pathologically proved asbestosis. The parenchymal abnormalities seen at in vitro HRCT included thickened intralobular lines (n = 7), thickened interlobular lines (n = 7), pleural-based opacities (n = 7), parenchymal fibrous bands (n = 5), subpleural curvilinear shadows (n = 4), ground-glass appearance (n = 4), traction bronchiectasis (n = 4), and honeycombing (n = 2). The thickened intralobular lines were shown histologically to be due to peribronchiolar fibrosis. Thickened interlobular lines were due mainly to interlobular fibrotic thickening in four lungs and edema in three. The peribronchiolar fibrosis was most severe in the subpleural lung regions, creating curvilinear line shadows and pleural-based areas of opacity. Some subpleural fibrosis extended proximally along the bronchovascular sheath to create bandlike lesions. Areas of ground-glass appearance on HRCT scans were shown to be the result of mild alveolar wall and interlobular septal thickening due to fibrosis or edema. Postmortem HRCT findings were similar to premortem HRCT findings and correlated well with the pathologic findings of asbestosis.     

Lung parenchymal changes in patients with ankylosing spondylitis

AIM: To assess lung parenchymal changes in ankylosing spondylitis (AS) using high resolution computed tomography (HRCT). METHODS: We included 78 AS patients whose average age was 33.87 (18-56) years with a ratio of 53 males to 25 females who were followed up for 3.88 (1-22) years on average. neumonia and tuberculosis were excluded. In a detailed examination of lung HRCT findings, we investigated the presence of parenchymal micronodules,parenchymal bands, subpleural bands, interlobular and intralobular septal thickening, irregularity of interfaces,ground glass opacity, consolidation, mosaic pattern,bronchial wall thickening, bronchial dilatation, tracheal dilatation, pleural thickening, emphysema, thoracic cage asymmetry, honeycomb appearance, structural distortion, apical fibrosis and other additional findings.RESULTS: In detailed HRCT evaluations, lung parenchymal changes were found in 46 (59%) of all patients. We found parenchymal bands in 21 (27%) cases, interlobular septal thickening in 9 (12%), emphysema in 9 (12%), apical fibrosis in 8 (10%), ground-glass opacities in 7 (9%), parenchymal micronodules in 5 (6%), irregularity in interfaces in 3 (4%), bronchial dilatation in 3 (4%), mosaic pattern in 2 (3%), pleural thickening in 2 (3%), consolidation in 1 (1%), bronchial wall thick ening in 1 (1%) and a subpleural band in 1 (1%) case. Furthermore, we detected subsegmental atelectasis in 2 patients and a cavitary lesion in 1 patient. CONCLUSION: Our study had the highest number of AS cases of all previous studies in evaluating lung paren chymal changes. The rate of lung parenchymal changes was slightly lower than that reported in recent literature.     

Bronchiolitis Obliterans after Allogenic Bone Marrow Transplantation: HRCT Findings

Objective

To evaluate the high resolution computed tomography (HRCT) findings of bronchiolitis obliterans (BO) after bone marrow transplantation (BMT).

Materials and Methods

During the past three years, 11 patients were diagnosed as having BO after BMT when they developed irreversible air flow obstruction, with an FEV₁ value of less than 80% of the baseline value, without any clinical evidence of infection. All 11 patients underwent HRCT, of whom eight also underwent follow-up HRCT. The HRCT images were assessed retrospectively for the presence of decreased lung attenuation, segmental or subsegmental bronchial dilatation, diminution of peripheral vascularity, centrilobular nodules, and branching linear structure on the inspiratory images. The lobar distribution of the decreased lung attenuation and bronchial dilatation was also examined. The presence of air trapping was investigated on the expiratory images. The interval changes of the HRCT findings were evaluated in those patients who had follow-up images.

Results

Abnormal HRCT findings were present in all cases; the most common abnormalities were decreased lung attenuation (n=11), subsegmental bronchial dilatation (n=6), diminution of peripheral vascularity (n=6), centrilobular nodules or branching linear structure (n=3), and segmental bronchial dilatation (n=3). Expiratory air trapping was noted in all patients. The decreased lung attenuation and bronchial dilatations were more frequent or extensive in the lower lobes. Interval changes were found in all patients with follow-up HRCT: increased extent of decreased lung attenuation (n=7); newly developed or progressed bronchial dilatation (n=4); and increased lung volume (n=3).

Conclusion

HRCT scans are abnormal in patients with BO, with the most commonly observed finding being areas of decreased lung attenuation. While the HRCT findings are not specific, it is believed that their common features can assist in the diagnosis of BO in BMT recipients.     

Usual Interstitial Pneumonia and Non-Specific Interstitial Pneumonia: Serial Thin-Section CT Findings Correlated with Pulmonary Function

Objective

We wanted to demonstrate and compare the serial high-resolution CTs (HRCT) and the pulmonary function test (PFT) findings of the usual interstitial pneumonia (UIP) and the non-specific interstitial pneumonia (NSIP).

Materials and Methods

The serial HRCT scans and the PFT results were retrospectively analysed and compared for 35 patients having UIP without significant honeycombing (UIP-w/o hc, < 5% of honeycombing at CT), 35 patients having UIP with honeycombing (UIP-w/i hc, ≥ 5% of honeycombing), and 25 patients with NSIP. The mortality rates were also compared. Follow-up CT scans were available in 75 patients (29 UIP-w/o hc patients, 22 UIP-w/i hc patients and 24 NSIP patients) and the follow-up periods ranged from 150 to 2,370 days. The initial and follow-up PFT data were available for 71 patients.

Results

On the initial CT, significant differences were present between the UIP-w/i hc patients and both the UIP-w/o hc patients and the NSIP patients in the overall extent, ground-glass opacity (GGO) away from the reticulation, reticulation and honeycombing (all p < 0.05). Improvement was noticed in five (17%) of 29 UIP-w/o hc patients, none of 22 UIP-w/i hc patients, and 9 (37%) of 24 NSIP patients; deterioration was noted in six (21%) UIP-w/o hc patients, two (9%) UIP-w/i hc patients and three (13%) NSIP patients (p = 0.044 between UIP-w/o and UIP-w/i hc; p = 0.637 between UIP-w/o hc and NSIP; p = 0.007 between UIP-w/i hc and NSIP). The serial changes of the pulmonary function in the NSIP patients were different from those noted for the UIP-w/i hc and UIP-w/o hc patients (p = 0.440 between UIP-w/o and UIP-w/i hc; p = 0.022 between UIP-w/o hc and NSIP; p = 0.003 between UIP-w/i hc and NSIP). Five (14%) of the 35 patients with UIP-w/o hc, 16 (46%) of the 35 patients with UIP-w/i hc and three (12%) of the 25 patients with NSIP died (p = 0.002, comparison for the three groups).

Conclusion

On CT, NSIP and UIP-w/o hc patients have similar patterns of parenchymal abnormalities and a similar likelihood of change in the extent of disease on follow-up. Patients with UIP-w/i hc have distinctive features and a worst prognosis.     

Comparison of Usual Interstitial Pneumonia and Nonspecific Interstitial Pneumonia: Quantification of Disease Severity and Discrimination between Two Diseases on HRCT Using a Texture-Based Automated System

Objective

To evaluate the usefulness of an automated system for quantification and discrimination of usual interstitial pneumonia (UIP) and nonspecific interstitial pneumonia (NSIP).

Materials and Methods

An automated system to quantify six regional high-resolution CT (HRCT) patterns: normal, NL; ground-glass opacity, GGO; reticular opacity, RO; honeycombing, HC; emphysema, EMPH; and consolidation, CONS, was developed using texture and shape features. Fifty-four patients with pathologically proven UIP (n = 26) and pathologically proven NSIP (n = 28) were included as part of this study. Inter-observer agreement in measuring the extent of each HRCT pattern between the system and two thoracic radiologists were assessed in 26 randomly selected subsets using an interclass correlation coefficient (ICC). A linear regression analysis was used to assess the contribution of each disease pattern to the pulmonary function test parameters. The discriminating capacity of the system between UIP and NSIP was evaluated using a binomial logistic regression.

Results

The overall ICC showed acceptable agreement among the system and the two radiologists (r = 0.895 for the abnormal lung volume fraction, 0.706 for the fibrosis fraction, 0.895 for NL, 0.625 for GGO, 0.626 for RO, 0.893 for HC, 0.800 for EMPH, and 0.430 for CONS). The volumes of NL, GGO, RO, and EMPH contribute to forced expiratory volume during one second (FEV₁) (r = 0.72, β values, 0.84, 0.34, 0.34 and 0.24, respectively) and forced vital capacity (FVC) (r = 0.76, β values, 0.82, 0.28, 0.21 and 0.34, respectively). For diffusing capacity (DL_co), the volumes of NL and HC were independent contributors in opposite directions (r = 0.65, β values, 0.64, -0.21, respectively). The automated system can help discriminate between UIP and NSIP with an accuracy of 82%.

Conclusion

The automated quantification system of regional HRCT patterns can be useful in the assessment of disease severity and may provide reliable agreement with the radiologists'' results. In addition, this system may be useful in differentiating between UIP and NSIP.     

成人肺炎支原体肺炎的CT表现

目的 认识成人肺炎支原体肺炎的CT及高分辨率CT（HRCT）表现。方法 16例经血清学检查证实的成人肺炎支原体肺炎,平均年龄41岁。回顾分析了所有病例的胸部常规CT及HRCT。结果 最常见的CT表现为磨玻璃样影12例,其中9例呈斑片状小叶分布;8例表现为气腔实变;9例可见“树芽征”;其他表现有小叶间隔增厚3例,支气管血管束增粗1例管。15例同时出现2种以上CT表现。结论 成人肺炎支原体肺炎的CT表现具有一定的特征性,有利于与细菌的肺炎区别。     

Subtle Pleural Metastasis without Large Effusion in Lung Cancer Patients: Preoperative Detection on CT

Objective

We wanted to describe the retrospective CT features of subtle pleural metastasis without large effusion that would suggest inoperable lung cancer.

Materials and Methods

We enrolled 14 patients who had open thoracotomy attempted for lung cancer, but they were proven to be inoperable due to pleural metastasis. Our study also included 20 control patients who were proven as having no pleural metastasis. We retrospectively evaluated the nodularity and thickening of the pleura and the associated pleural effusion on the preoperative chest CT scans. We reviewed the histologic cancer types, the size, shape and location of the lung cancer and the associated mediastinal lymphadenopathy.

Results

Subtle pleural nodularity or focal thickening was noted in seven patients (50%) having pleural metastasis and also in three patients (15%) of control group who were without pleural metastasis. More than one of the pleural changes such as subtle pleural nodularity, focal thickening or effusion was identified in eight (57%) patients having pleural metastasis and also in three patients (15%) of the control group, and these findings were significantly less frequent in the control group patients than for the patients with pleural metastasis (p = 0.02). The histologic types of primary lung cancer in patients with pleural metastasis revealed as adenocarcinoma in 10 patients (71%) and squamous cell carcinoma in four patients (29%). The location, size and shape of the primary lung cancer and the associated mediastinal lymphadenopathy showed no significant correlation with pleural metastasis.

Conclusion

If any subtle pleural nodularity or thickening is found on preoperative chest CT scans of patients with lung cancer, the possibility of pleural metastasis should be considered.     

Cystic Lung Disease: a Comparison of Cystic Size, as Seen on Expiratory and Inspiratory HRCT Scans

Objective

To determine the effects of respiration on the size of lung cysts by comparing inspiratory and expiratory high-resolution CT (HRCT) scans.

Materials and Methods

The authors evaluated the size of cystic lesions, as seen on paired inspiratory and expiratory HRCT scans, in 54 patients with Langerhans cell histiocytosis (n = 3), pulmonary lymphangiomyomatosis (n = 4), confluent centrilobular emphysema (n = 9), paraseptal emphysema and bullae (n = 16), cystic bronchiectasis (n = 13), and honeycombing (n = 9). Using paired inspiratory and expiratory HRCT scans obtained at the corresponding anatomic level, a total of 270 cystic lesions were selected simultaneously on the basis of five lesions per lung disease. Changes in lung cyst size observed during respiration were assessed by two radiologists. In a limited number of cases (n = 11), pathologic specimens were obtained by open lung biopsy or lobectomy.

Results

All cystic lesions in patients with Langerhans cell histiocytosis, lymphangiomyomatosis, cystic bronchiectasis, honeycombing, and confluent centrilobular emphysema became smaller on expiration, but in two cases of paraseptal emphysema and bullae there was no change.

Conclusion

In cases in which expiratory CT scans indicate that cysts have become smaller, cystic lesions may communicate with the airways. To determine whether, for cysts and cystic lesions, this connection does in fact exist, paired inspiratory and expiratory HRCT scans are necessary.     

Chronic interstitial pneumonia in young patients undergoing lung transplantation or autopsy: clinico-radiologic-pathologic observations from a single institution

Purpose

To retrospectively evaluate high-resolution computed tomography (HRCT) findings and clinical diagnoses of chronic interstitial pneumonia (IP) with a poor prognosis in young patients (≤50 years).

Materials and methods

HRCT images of 8 men and 7 women (mean age 34.8 years) obtained before lung transplantation or autopsy were reviewed. After reviewing whole lung specimens and pathologic diagnoses, all patients were clinically diagnosed according to the 2010 idiopathic pulmonary fibrosis/usual interstitial pneumonia (IPF/UIP) consensus statement.

Results

HRCT images revealed intralobular reticular opacity, air cysts, ground glass opacity, traction bronchiectasis, and interlobular septal thickening. Intralobular reticular opacity was the most extensive finding. Abnormal findings existed predominantly in both the peripheral and lower lung zones in only 1 patient. Classifications of HRCT patterns were “UIP” (n = 2), “inconsistent with UIP” (n = 11), and “indeterminate UIP” (n = 2). Multidisciplinary diagnoses were “IPF/UIP” (n = 1), “possible IPF/UIP” (n = 1), “IP with connective tissue disease” (n = 7), “fibrotic nonspecific IP” (n = 1), and “unclassified IP” (n = 5).

Conclusion

The most extensive HRCT finding was intralobular reticular opacity. Most HRCT images differed from typical IPF/UIP, and IPF/UIP was uncommon in young patients with chronic IP with a poor prognosis.

     

Herpes-Simplex-Virus 1 pneumonia in the immunocompromised host: high-resolution CT patterns in correlation to outcome and follow-up

Objective

To identify the high-resolution CT (HRCT) patterns of Herpes-Simplex-Virus 1 (HSV) pneumonia in immunocompromised patients and correlate findings to outcome and radiographic follow-up until death or complete resolution of findings.

Patients and methods

HRCT data-sets and plain radiographic follow-ups were reviewed in 25 immunocompromised patients with confirmation of new onset HSV-1 pneumonia. Pattern and distribution of abnormalities was assessed by two chest radiologists and findings evaluated regarding outcome and dynamics.

Results

The most frequent CT abnormalities included ground-glass attenuation (n = 18; 72%) in a bilateral, symmetric and random distribution, air-space consolidations (n = 13; 52%) in a bilateral, asymmetric and peribronchial allocation and interlobular septal thickening (n = 6; 24%).When classified by leading HRCT pattern, patients subdivided into distinct groups with either dominant ground-glass attenuation or air-space consolidation. Six patients died after a median 8 days of diagnosis; the median interval until complete radiographic remission of pathology was 20 days. Pre-dominance of air-space consolidations was associated with significant delay of improvement (p = 0.023); however, patient outcome was comparable in both subgroups (p = 0.9).

Conclusion

Diagnosis of HSV pneumonia is challenging and requires familiarity with two distinct HRCT patterns: predominance of ground-glass opacities or air-space consolidations. Whilst the two forms are not linked to patient outcome they demonstrate a variable dynamic at follow-up.     

Serial evaluation of high-resolution CT findings in patients with pneumonia in novel swine-origin influenza A (H1N1) virus infection

Objectives

The purpose of our study was to review the changes in the serial high-resolution CT (HRCT) findings from patients with novel swine-origin influenza A (H1N1) virus (S-OIV) infection.

Methods

HRCT findings of 70 patients with presumed or laboratory-confirmed novel S-OIV infection were reviewed. The pattern (consolidation, ground glass, fibrosis and air trapping), distribution and extent of abnormality of the lesions on the HRCT were evaluated at different time points. To assess changes that occurred over time, the CT scans in 56 patients were examined in sequence.

Results

The most common CT findings in patients with S-OIV infection are ground-glass opacities with or without consolidation at the first week. The abnormalities peaked at the second week and resolved after that time, which resulted in substantial reduced residual disease at 4 weeks or later. The development of fibrosis was noted in the first week and peaked at the third week of illness (34.7%), then decreased slowly after that time. The mean time of air trapping being noted after the onset of symptoms was 55.5±20.6 days. Comparing the findings of initial CT, most results (96.4%) of follow-up chest CT findings showed improvement (p<0.01).

Conclusion

The abnormalities of ground-glass opacities and/or consolidation on initial CT scans tended to resolve to fibrosis, which then resolved completely or displayed substantially reduced residual disease. HRCT may show more changes in disease progression and play an important role in the evaluation of severe S-OIV.A novel swine-origin influenza A (H1N1) virus (S-OIV) was first reported in Mexico and became rampant globally later on in spring 2009 [1]. The World Health Organization declared the first Phase 6 global influenza pandemic of the century on 11 June 2009 [2]. During peak periods of influenza in autumn to winter of that year, a proportion of patients developed severe acute respiratory distress syndrome (ARDS), and some died of the disease. Serial chest radiography has been the main technique in the initial investigation of patients with suspected H1N1. However, multislice CT (MSCT) scanning is more sensitive than chest radiography, providing more detailed radiological features. Previous studies have reported that the predominant CT findings of disease were unilateral or bilateral multifocal peribronchovascular and/or subpleural ground-glass opacities (GGOs) with or without consolidation [1,3]. Little is known, however, about sequential MSCT findings during the subsequent course of pneumonia with H1N1. The purpose of this study was to evaluate the radiological changes on serial thin-section chest CT scans in patients with H1N1 during the acute and convalescent periods of the illness.