Characteristics of Coronary Artery to Pulmonary Artery Fistula on Coronary Computed Tomography Angiography.

OBJECTIVE: The aim of the study was to evaluate the characteristics of coronary artery-to-pulmonary artery fistula (CPAF) found by coronary computed tomography (CT) angiography. METHODS: Among 10,121 cases of coronary CT angiography performed for 7 years, we found 32 cases of CPAF. We retrospectively evaluated the demographics, clinical symptoms, and anatomical characteristics such as the origin, number of origins, course, opening site of the fistula, and the presence of aneurysmal changes (defined as dilatation 1.5 times the diameter of the origin). We also categorized the fistula openings according to size compared with that of the proximal left anterior descending coronary artery. RESULTS: The patients were 14 men and 18 women with a mean (range) age of 56.5 (34-86) years. Nineteen patients had no related symptoms, and the other 13 patients had symptoms such as angina, chest discomfort, palpitations, or shoulder pain. Among these patients, 2 patients were diagnosed with coronary artery disease. The origins of CPAF were single (n = 15, 46.9%) or multiple (n = 17, 53.1%). The CPAFs arose most commonly from the conus branch of the right coronary artery (n = 20, 62.5%) and proximal left anterior descending (n = 17, 53.1%). All CPAFs coursed anteriorly to the main pulmonary artery and drained into the anterolateral aspect. Twenty-five patients (78.1%) exhibited aneurysmal changes. The openings were small in 13 (40.6%), medium in 13 (40.6%), and large in 6 (18.8%) patients. CONCLUSIONS: More than half of patients with CPAF had no related symptoms. Coronary artery-to-pulmonary artery fistula may have a single origin or multiple origins. All of the CPAFs coursed anteriorly to the main pulmonary artery and drained into the anterolateral aspect; the CPAFs identified here frequently exhibited aneurysmal changes.

Low attenuation areas in normal costal cartilages on CT: clinical implication and correlation with histology.

While normal costal cartilages are known to be homogenous in attenuation on computed tomography (CT), they frequently show internal low attenuation. This study was performed to assess CT features of the low attenuation and to correlate them with histological features. Chest CT scans of 80 patients without chest wall abnormalities in the first eight decades of age with ten consecutive patients in each decade were reviewed. Histological examinations and CT of three costal cartilage specimens, one each from three cadavers, were done. Of the 80 patients, low attenuation areas were noted in 32% of the upper seven costal cartilages and in 64 patients (80%) without significant sexual difference (P = 0.503 and 0.786, respectively). The areas appeared more frequently in the lower costal cartilages than the upper ones, and were mostly symmetrical in distribution (82%). They were usually ill defined (74%) and similar in attenuation to the chest wall muscle (94%), located centrally (100%), and at most a half of the cartilage diameter. In all three cartilage specimens, central areas were grossly distinct from surrounding areas, and were corresponded to low attenuation areas on CT. At histological exam, the central areas showed multiple foci of vascularized loose connective tissue and fat on myxoid background, generally agreeing with the previous description of cartilage canals, a kind of nutrient channel. In conclusion, normal costal cartilages can show central low attenuation areas, which are typically symmetrical in distribution and at most a half of the cartilage diameter.

Left costomediastinal recess of the pleura, the potential pleural space anterior to the heart.

OBJECTIVE: To investigate clinical implications of the left costomediastinal recess of the pleura. METHODS: The left anterior pleural anatomy was studied in 12 cadavers. Chest computed tomography (CT) scans of 68 healthy/near-healthy patients were reviewed for the recess. Twenty pleural lesions in the recess were analyzed on CT. Eight cases of left paracardiac pericardiocentesis were analyzed for pleural complications. RESULTS: Two fresh cadavers showed the recess to be wider downward, measuring 75 and 55 mm in width at the sixth intercostal space. None of the 68 healthy/near- healthy CT scans displayed the recess. Twenty recess lesions were connected to similar pleural lesions surrounding the left lung (n = 19) or showed an isolated lesion therein only partly facing the left lung (n = 1). Ipsilateral pleural effusion complicated 3 of 7, successful left paracardiac pericardiocentesis. CONCLUSION: Regardless of their contiguity with the lung, the differential diagnosis of precordial lesions should include pleural diseases in the recess. Left anterior pericardiocentesis unavoidably violates the intervening recess, sometimes causing pleural effusion.

Enterobacter cloacae Sacroiliitis with Acute Respiratory Distress Syndrome in an Adolescent.

Enterobacter cloacae has emerged as an important nosocomial pathogen, but is rarely a cause of sacroiliitis. Herein, we present the first reported case of Enterobacter cloacae sacroiliitis associated with sepsis and acute respiratory distress syndrome (ARDS). A previously healthy 14-year-old boy presented with low-grade fever and pain in the left side of the hip that was aggravated by walking. Pelvic computed tomography (CT) showed normal findings, and the patient received supportive care for transient synovitis with no antibiotics. However, there was no clinical improvement. On the third day of hospitalization, magnetic resonance imaging of the hip revealed findings compatible with sacroiliitis, for which vancomycin and ceftriaxone were administered. The patient suddenly developed high fever with dyspnea. Chest radiography and CT findings and a PaO2/FiO2 ratio <200 mmHg were suggestive of ARDS; the patient subsequently received ventilatory support and low-dose methylprednisolone infusions. Within one week, defervescence occurred, and the patient was able to breathe on his own. Following the timely recognition of, and therapeutic challenge to, ARDS, and after 6 weeks of parenteral antimicrobial therapy, the patient was discharged in good health with no complications.

Near fatal desquamative interstitial pneumonia with bilateral recurrent tension pneumothorax.

Desquamative interstitial pneumonia (DIP) is an uncommon form of interstitial lung disease demonstrating good response to corticosteroid therapy and favorable prognosis. In rare cases, patients with DIP fail to respond to corticosteroid therapy, and may progress to end-stage fibrotic lung disease with respiratory failure. For such patients, well defined treatment regimen does not exist until now. We report a rare case of near fatal DIP with recurrent bilateral tension pneumothorax despite of corticosteroid maintenance therapy. Clinical and radiological findings improved with surgical intervention in addition to combination therapy with prednisolone and clarithromycin. The patient has remained in an improved state and has been receiving prednisolone and clarithromycin for 9 months.

Left ventricular pseudoaneurysm after valve replacement.

We present a case of left ventricular pseudoaneurysm, which is a very rare and fatal complication of cardiac procedures such as mitral valve replacement. A 55-year-old woman presented to the Department of Thoracic and Cardiovascular Surgery at Hanyang University Seoul Hospital with chest pain. Ten years prior, the patient had undergone double valve replacement due to aortic regurgitation and mitral steno-insufficiency. Surgical repair was successfully performed using a prosthetic pericardial patch via a left lateral thoracotomy.

Primary Sternal Osteomyelitis Caused by Actinomyces israelii.

Primary sternal osteomyelitis is a rare disease. Common infectious organisms causing primary sternal osteomyelitis include Staphylococcus aureus and Pseudomonas aeruginosa. Actinomyces species are common saprophytes of the oral cavity, but there have been few reports in the literature of primary sternal osteomyelitis caused by Actinomyces species. We describe a case of primary sternal osteomyelitis caused by Actinomyces israelii without pulmonary involvement.

Effects of radiation therapy on the lung: radiologic appearances and differential diagnosis.

Radiation-induced lung disease (RILD) due to radiation therapy is common. Radiologic manifestations are usually confined to the lung tissue within the radiation port and are dependent on the interval after completion of treatment. In the acute phase, RILD typically manifests as ground-glass opacity or attenuation or as consolidation; in the late phase, it typically manifests as traction bronchiectasis, volume loss, and scarring. However, the use of oblique beam angles and the development of newer irradiation techniques such as three-dimensional conformal radiation therapy can result in an unusual distribution of these findings. Awareness of the atypical manifestations of RILD can be useful in preventing confusion with infection, recurrent malignancy, lymphangitic carcinomatosis, and radiation-induced tumors. In addition, knowledge of radiologic findings that are outside the expected pattern for RILD can be useful in diagnosis of infection or recurrent malignancy. Such findings include the late appearance or enlargement of a pleural effusion; development of consolidation, a mass, or cavitation; and occlusion of bronchi within an area of radiation-induced fibrosis. A comprehensive understanding of the full spectrum of these manifestations is important to facilitate diagnosis and management in cancer patients treated with radiation therapy.

Telangiectatic pulmonary arteriovenous malformation.

Telangiectatic pulmonary arteriovenous malformation is defined as a pulmonary arteriovenous malformation involving every segmental artery of at least one lobe of the lung. The authors report a case of telangiectatic pulmonary arteriovenous malformation in the left lower lobe of the lung.

Omental mesothelial cyst herniated to the thorax through the esophageal hiatus: a case report.

Both mesothelial cyst in the omentum and omental herniation through the esophageal hiatus without abdominal visceral involvement are rare. We report a case of omental mesothelial cyst herniated to the thorax through the esophageal hiatus.

Pulmonary tuberculosis: another disease showing clusters of small nodules.

OBJECTIVE: Pulmonary sarcoidosis was recently reported to show the "sarcoid galaxy" sign, indicating large pulmonary nodules composed of coalescent small nodules. The purpose of this study was to review cases of pulmonary tuberculosis showing CT features indistinguishable from the sarcoid galaxy sign. CONCLUSION: Large nodules arising from the coalescence of small nodules may be seen in active tuberculosis and in sarcoidosis. The CT finding was termed "clusters of small nodules" instead of the "sarcoid galaxy sign" in this article. A single cluster of small nodules, clusters of small nodules in the superior segment of the lower lobe, or clusters of small nodules not associated with lymphadenopathy or associated with tree-in-bud lesions would favor the diagnosis of active pulmonary tuberculosis rather than pulmonary sarcoidosis.

Tuberculous pleural effusion: new pulmonary lesions during treatment.

PURPOSE: To evaluate patients who have a paradoxical response (development of new opacities) to treatment for tuberculous pleural effusion not related to acquired immunodeficiency syndrome. MATERIALS AND METHODS: In 16 patients, follow-up chest radiographs (n = 16) and initial (n = 2) and follow-up (n = 9) computed tomographic (CT) scans of the chest were retrospectively reviewed by two radiologists. Patient records (n = 16) and results of percutaneous needle aspiration and/or biopsy (n = 6) were reviewed by one radiologist. RESULTS: Eighteen episodes of new lesion development were identified on radiographs in 16 patients. Each episode showed single (nine of 18 episodes, 50%) or multiple (nine of 18 episodes, 50%) nodules, most of which were in the peripheral lung (16 of 18 episodes, 89%) ipsilateral to the side of previous effusion (17 of 18 episodes, 94%). On CT scans, all lesions were peripheral pulmonary nodules, not round atelectasis. Needle aspiration and/or biopsy of the lesions showed findings consistent with tuberculosis in all six patients. Lesions usually evolved within 3 months after the start of medication (13 of 18 episodes) and finally disappeared (15 episodes) or left residual opacities (three episodes) 3-18 months later, with continuation of medication. CONCLUSION: New lung lesions that develop during medication for tuberculous pleural effusion should be considered a transient worsening that ultimately improves with continuation of medication.

Does contrast enhancement on CT suggest tumor response for chemotherapy in small cell carcinoma of the lung?

PURPOSE: The purpose of this article is to assess the correlation between contrast enhancement on CT and the tumor reduction ratio in small cell carcinoma of the lung after first-line chemotherapy. MATERIALS AND METHODS: Twenty-eight patients with small cell carcinoma of lung underwent preenhancement and postenhancement CT scans before and after first-line chemotherapy, followed by second-line chemotherapy in 7 patients who had relapsed. The authors retrospectively analyzed the correlation between the tumor reduction ratio and the CT numbers of contrast enhancement in each case by multiple regression analysis using SPSS. RESULTS: The mean tumor-reduction ratio was 58.2 +/- 43.2% after first-line chemotherapy, and the mean CT enhancement was 33.2 +/- 11.0 Hounsfield units (HU). The correlation coefficient between the tumor reduction ratio and the CT numbers of contrast enhancement was 0.57 (r = 0.32), and p value was < 0.002. After chemotherapy, more than 90% tumor reduction was seen in 11 patients. They revealed an average 41.9 +/- 7.6 HU tumor enhancement. Less than 50% tumor reduction was seen in 10 patients. They revealed an average 26.2 +/- 7.9 HU tumor enhancement. If these criteria of 30 HU contrast enhancement and 80% tumor reduction ratio were applied as a guide for chemotherapy response, the sensitivity, specificity, positive predictive value, and negative predictive value would be calculated as 85.7%, 84.6%, 85.7%, and 84.6%, respectively. CONCLUSION: In small cell carcinoma of the lung, it is statistically proven that the more enhanced tumor on CT, the better response to chemotherapy. Tumor enhancement of 30 HU is a suggestive guide for chemotherapy response in patients with small cell carcinoma.

Low-dose spiral CT: application to surface-rendered three-dimensional imaging of central airways.

PURPOSE: The purpose of this work was to assess the utility of low-dose spiral CT for three-dimensional imaging of the central airways. METHOD: Spiral CT was performed in 15 patients using two tube currents (50 and 240 mA), producing 30 CT data sets. Surface-rendered virtual bronchoscopy (VB) and shaded surface display (SSD) images were assessed by three radiologists for image quality. The radiologists were also asked to compare 15 matched pairs each of 50 and 240 mA VB and SSD images, blindly select the 240 mA image, and record differences in diagnostic quality between the matched images. RESULTS: No significant difference in image quality was noted with 50 or 240 mA. Only 51.1% of 240 mA SSD and 51.1% of 240 mA VB images were correctly identified. Differences in diagnostic quality, noted in 84.4% of SSD and 33% of VB image pairs, were not ascribed to image noise. CONCLUSION: Image quality of surface-rendered three-dimensional images of the central airways is preserved using a lower tube current.