Atypical pulmonary metastases: spectrum of radiologic findings.

Typical radiologic findings of a pulmonary metastasis include multiple round variable-sized nodules and diffuse thickening of interstitium. In daily practice, however, atypical radiologic features of metastases are often encountered that make distinction of metastases from other nonmalignant pulmonary diseases difficult. A detailed knowledge of the atypical radiologic features of a pulmonary metastasis with a good understanding of the histopathologic background is essential for correct diagnosis. Squamous cell carcinoma is regarded as the most common cell type of a cavitating metastasis, but metastatic nodules from adenocarcinomas and sarcomas also cavitate occasionally. Calcification can occur in a metastatic sarcoma or adenocarcinoma, which makes differentiation from a benign granuloma or hamartoma difficult. Peritumoral hemorrhage results in areas of nodular attenuation surrounded by a halo of ground-glass opacity. Pneumothorax commonly occurs in metastases from an osteosarcoma. Air-space consolidation is often seen in cases of metastases from gastrointestinal tract malignancies. Even though tumor emboli in pulmonary arteries can be seen at computed tomography, diagnosis is difficult because they are located in small or medium arteries. A common radiologic appearance of an endobronchial metastasis is an atelectasis. In cases of an endobronchial or a solitary pulmonary metastasis, differentiation between bronchogenic carcinoma and metastasis is difficult. Dilated vascular structures within the mass can be seen in metastatic sarcomas. A sterilized metastasis after chemotherapy is radiologically indistinguishable from a residual viable tumor. Benign tumors such as uterine leiomyomas and giant cell tumors of the bone rarely metastasize to the lung.     

原发性肺非何杰金淋巴瘤的影像诊断

目的：研究原发性肺淋巴瘤的影像诊断，方法：7例均经病理和临床证实的原发性肺非何杰金淋巴瘤，均作X线胸片、腹部B超检查，其中5例作胸部CT。结果：6例单发和1例多发性结节(两肺各一灶)或肿块，病变分布无肺叶偏向，病灶密度较低而不均。6个病灶边缘毛糙不规则，1个病灶边缘光整，另一个病灶边缘部分光整，其中2个病灶边缘分叶，2个病灶见长短毛刺。1个病灶见空洞。作胸部CT的5例均见空气支气管征。其中1例伴纵隔淋巴结肿大，5例合并肺叶或肺段的肺不张或部分肺不张，3例侵犯胸壁伴少量胸水。结论：原发性肺淋巴瘤的影像表现多样，非特异性，常见有空气支气管征的边缘毛糙的结节或肿块。本病应与肺癌、隐源性机化性肺炎鉴别，最后定性诊断需病理检验证实。     

Congenital unilateral pulmonary vein atresia: radiologic findings in three adult patients

OBJECTIVE: The purpose of our study is to describe the radiologic findings of adult patients presenting with congenital unilateral pulmonary vein atresia. CONCLUSION: Chest radiography in affected patients typically reveals a small hemithorax and ipsilateral pulmonary artery as well as ipsilateral septal thickening. CT shows, in addition, ground-glass attenuation, the absence of a pulmonary vein connection to the left atrium, and abundant mediastinal venous collateral vessels. MR imaging is helpful in further characterizing the vascular abnormalities. Angiography may help to confirm the diagnosis.     

Colorectal hemangioma: radiologic findings

The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.     

Lyme arthritis: radiologic findings

Lyme disease is a newly recognized, multi-system disorder that may be associated with chronic arthritis. Of 25 patients with severe arthritic manifestations the most frequent radiographic finding was knee joint effusion. Intra-articular edema was often accompanied by a continuum of soft-tissue changes involving the infrapatellar fat pad, periarticular soft tissues, and the entheses, which were sometimes thickened, calcified, or ossified. Later in the illness, the joints of some patients showed typical changes of an inflammatory arthritis, including juxta-articular osteoporosis, cartilage loss, and cortical or marginal bone erosions. Less commonly, other patients demonstrated changes more characteristic of degenerative arthritis, including cartilage loss, subarticular sclerosis, and osteophytosis. Joint involvement of Lyme disease has similarities to juvenile arthritis and Reiter syndrome, but can usually be distinguished clinically and serologically from these entities.     

Spectrum of pulmonary aspergillosis: histologic, clinical, and radiologic findings.

Aspergillosis is a serious pathologic condition caused by Aspergillus organisms and is frequently seen in immunocompromised patients. At computed tomography (CT), saprophytic aspergillosis (aspergilloma) is characterized by a mass with soft-tissue attenuation within a lung cavity. The mass is typically separated from the cavity wall by an airspace ("air crescent" sign) and is often associated with thickening of the wall and adjacent pleura. CT findings in allergic bronchopulmonary aspergillosis consist primarily of mucoid impaction and bronchiectasis involving predominantly the segmental and subsegmental bronchi of the upper lobes. Aspergillus necrotizing bronchitis may manifest as an endobronchial mass, obstructive pneumonitis or collapse, or a hilar mass. Bronchiolitis is characterized by centrilobular nodules and branching linear or nodular areas of increased attenuation ("tree-in-bud" pattern). Obstructing bronchopulmonary aspergillosis mimics allergic bronchopulmonary aspergillosis at CT and manifests as bilateral bronchial and bronchiolar dilatation, large mucoid impactions, and diffuse lower lobe consolidation caused by postobstructive atelectasis. Characteristic CT findings in angioinvasive aspergillosis consist of nodules surrounded by a halo of ground-glass attenuation ("halo sign") or pleura-based, wedge-shaped areas of consolidation. Although imaging findings in pulmonary aspergillosis may be nonspecific, in the appropriate clinical setting, familiarity with the CT findings may suggest or even help establish the diagnosis.     

Bronchopulmonary sequestration: radiologic findings

Bronchopulmonary sequestration (BPS) is a nonfunctioning bronchopulmonary tissue that is separate from the tracheobronchial tree and receives arterial blood from the systemic circulation. BPS has a wide spectrum of imaging findings. Surgery is generally indicated for the treatment of BPS. It is important to demonstrate the arterial supply and venous drainage of the sequestered segment preoperatively. Today, with the help of noninvasive imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI), preoperative diagnosis of BPS can be made easily, so, invasive techniques such as angiography are not required frequently. In this report, radiological findings of BPS were retrospectively reviewed.     

Semiinvasive pulmonary aspergillosis in chronic obstructive pulmonary disease: radiologic and pathologic findings in nine patients

OBJECTIVE: The purpose of this study is to assess the radiographic, thin-section CT, and histologic findings of semiinvasive aspergillosis in patients with chronic obstructive pulmonary disease (COPD). MATERIALS AND METHODS: The study included nine patients with COPD seen at the Hospital de Sant Pau during a 3-year period who had histopathologically proven aspergillosis with tissue invasion. Chest radiography and thin-section (2-mm collimation) CT of the chest were available in all cases. RESULTS: Nine patients had semiinvasive aspergillosis proven at autopsy (n = 7) or by thoracoscopically guided lung biopsy (n = 2). The radiologic findings consisted of parenchymal consolidation (n = 6) and nodules larger than 1 cm in diameter (n = 3). Parenchymal consolidation involved the upper lobes in five patients and was bilateral in four. Cavitation was present in two of the patients with consolidation and in two of the patients with nodular opacities. Adjacent pleural thickening was revealed by CT in four patients. Histologically, the areas of consolidation represented active inflammation and intraalveolar hemorrhage containing Aspergillus organisms. In the three patients with multiple cavitated nodules, a variable degree of central necrosis was observed. The inflammatory infiltrate extended into the surrounding lung parenchyma, and adjacent areas of hemorrhage were also seen. Aspergillus colonies were identified within the lung tissue. CONCLUSION: Upper lobe consolidation or multiple nodules in patients with COPD should raise the possibility of semiinvasive aspergillosis.     

Traumatic adrenal hemorrhage: radiologic findings

Four patients with traumatic hemorrhage in the right adrenal gland were examined with computed tomography (CT) and ultrasound (US) (initial US studies in three patients; follow-up study at least 1 month after the trauma in all patients). CT showed an enlarged inhomogeneous gland of normal to increased attenuation. This finding was associated with stranding of the periadrenal fat and stranding of the subcutaneous fat of the right flank, which corresponded to the site of trauma. US showed an enlarged, hyperechoic mass with a bright central echo that became cystic on follow-up examinations. Magnetic resonance imaging, performed in one patient, showed an enlarged gland that was isointense with liver on T1-weighted images and had increased signal intensity on T2-weighted images. Stranding of the periadrenal and subcutaneous fat of the right flank was present on T2-weighted images and appeared as streaky areas of increased signal intensity.     

Unilateral absence of the pulmonary veins: an unusual diagnosis with characteristic imaging findings

BackgroundCongenital unilateral absence of the pulmonary vein (UCAPV) is a rare entity with characteristic clinical and imaging findings. Despite its congenital nature, the radiographic findings and symptoms of UCAPV may not be recognized at birth and patients may present in childhood or early adulthood with findings that may mimic other diagnoses.MethodsThe evolution of imaging findings in UCAPV is presented through two cases, one of which demonstrates the progression of findings over several years. The embryologic basis of this entity is reviewed and the clinical presentation and characteristic imaging findings including radiographs, nuclear scintigraphy, computed tomography, magnetic resonance imaging and cardiac catheterization are demonstrated.ResultsCharacteristically, normal at birth, radiographs demonstrate the gradual development of a small lung and ipsilateral pulmonary artery over time. In addition to unilateral absence of the pulmonary veins on CT or MRI, a mediastinal “soft tissue mass” reflecting the development of mediastinal collaterals is a common finding and should be recognized as secondary to the absent ipsilateral pulmonary veins rather than as a primary process causing occlusion of the pulmonary veins. Scintigraphy will show absent perfusion to the affected lung.ConclusionAwareness of the distinctive imaging findings in this unusual condition is critical to avoid misdiagnosis and to prevent the consequences of UCAPV which include pulmonary hypertension and extensive venous collaterals with or without hemoptysis, both of which may prevent definitive repair.     

Myelolipoma: radiologic findings in seven patients

Myelolipomas are rare, non-functioning, benign tumors which occur both in the adrenal gland and in various extra-adrenal locations, particularly presacrally. We report the computed tomographic (CT) and ultrasonographic (US) findings in seven patients with pathologically proven myelolipomas. Magnetic resonance (MR) imaging was also obtained in one. Our series includes one patient with bilateral myelolipomas, one with a presacral myelolipoma, and one with a calcified myelolipoma. Radiographic findings can suggest the diagnosis. A characteristic mass is lucent on plain films, is echogenic on US, shows fat attenuation on CT, is avascular at angiography, and has a signal intensity similar to that of fat on T1-weighted MR images. However, the absence of fat can render imaging findings nonspecific. Percutaneous needle biopsy is a simple, safe, effective way to establish the diagnosis when imaging features are not typical.     

Infantile-onset multisystem inflammatory disease: radiologic findings

Infantile-onset multisystem inflammatory disease (IOMID) is a newly recognized disease that is similar to systemic-onset juvenile rheumatoid arthritis (JRA). The clinical symptoms of IOMID include rash, fever, lymphadenopathy, chronic meningitis, uveitis, and a distinct arthropathic condition. Skeletal involvement is surprisingly constant. The long bones become short, bowed, and widened. The metaphyses flare and simulate rickets. Grotesque epiphyses appear fragmented early in the course of the disease but are gradually incorporated into the widened shafts. We observed these and other radiologic findings in the four cases described in the present study. The findings are distinctive and allow for a specific diagnosis.     

Cloacal exstrophy: radiologic findings in 13 patients

Cloacal exstrophy is a complex, multisystem malformation that has not received much attention in the radiologic literature. The clinical histories and imaging studies of 13 cases of cloacal exstrophy proved surgically or at autopsy were reviewed. Radiologic observations were based on skeletal plain films (13), contrast-enhanced examinations of the genitourinary system (12), abdominopelvic sonograms (nine), gastrointestinal studies (seven), CT scans of the pelvis and CNS (seven), MR images of the pelvis and CNS (six), renal nuclear medicine scans (three), myelography (three), and three-dimensional scans of the pelvis (two). Genitourinary and gastrointestinal abnormalities identified in our 13 patients included bladder malformations (13), hindgut anomalies (13), undescended testes (five), malrotation (five), duplicated müllerian structures (four), and renal ectopia (four). Skeletal abnormalities included symphysis pubis diastasis (13), posterior element dysraphism (12), vertebral segmentation anomalies (12), clubfeet (six), and hip dislocations (five). CNS anomalies included meningocele (nine) and Chiari malformation (one). Immediate surgical closure of the defect with maximal bowel preservation and diverting colostomy offers optimal chances for survival. Appropriate preoperative gastrointestinal and genitourinary evaluation is essential.