Aberrant left subclavian artery in tetralogy of Fallot.

The anatomy of the aberrant left subclavian artery in a right-sided aortic arch is different in patients with tetralogy of Fallot than in persons with a normal heart. In all eight patients with tetralogy of Fallot and aberrant left subclavian artery in this series, the left subclavian artery arose directly from the distal aortic arch. In contrast, normal persons with right aortic arch and aberrant left subclavian artery invariably have an aortic diverticulum from which the left subclavian artery and the left ductus arteriosus originate. The possible different embryologic events responsible for these two forms of aberrant left subclavian artery are discussed.

Tetralogy of Fallot with atrioventricular canal. An angiographic study.

Tetralogy of Fallot associated with atrioventricular (AV) canal is a well-recognized cardiac malformation; its surgical repair carries a high mortality, which is related partly to the complexity of the defect and partly to incomplete diagnosis. Hence an accurate preoperative diagnosis is essential. This communication describes the angiographic features observed in 17 patients with tetralogy of Fallot and AV canal with emphasis on the morphology of the right AV valve as seen during the right ventriculogram. A complete anatomic diagnosis can be consistently made from right and left ventriculograms performed in axial projections.

Accessory flaplike tissue causing ventricular outflow obstruction.

In three cases, two in children and one in a young adult, ventricular outflow obstruction was caused by a valvelike flap of accessory endocardial tissue. The angiocardiographic feature was that of a narrow radiolucent, crescent-shaped or linear filling defect corresponding to the site of obstruction. Resection of the accessory tissue was performed in each case at the time of correction of associated conditions. In one case (a woman 20 years of age) the obstructing membrane was in the outflow tract of the right ventricle, and a ventricular septal defect was associated. In each of the other two cases the outflow tract of the left ventricle was the site of obstruction. In one (a 14-month-old boy), an ostium primum type of atrial septal defect and cleft mitral valve were associated; in the remaining case (a 7-year-old boy) complete transposition and ventricular septal defect were also present. In the latter case a Mustard procedure was performed and was followed by death. Successful results were obtained in the first two patients.

Detection of emphysema with computed tomography. Correlation with pulmonary function tests and chest radiography.

We studied 60 male patients who had concurrent chest films (CXR), computed tomography scans (CT) and pulmonary function tests (PFT) to assess the sensitivity of CT and conventional films in detecting emphysema compared with PFT. We also sought to determine whether emphysema could be diagnosed by CT in patients with normal pulmonary function. Using a method similar to that proposed by Bergin, we scored the severity of emphysema depicted by CT, and using arterial deficiency and bullae as criteria, we estimated the degree of emphysema on CXR. There was a significant inverse correlation between CT scores for emphysema and percentage predicted values of DLco/VA (r = -0.650), FEV1 (r = -0.552), and FVC (r = -0.409), (P less than 0.001). A significant but smaller correlation also was noted with the CXR scores and percentage predicted: DLco/VA (r = -0.564), FEV1 (r = -0.454), and FVC (r = -0.355), (P less than 0.005). When decreased diffusion capacity and airway obstruction were used as functional criteria of emphysema, CT was as sensitive as PFT and more sensitive than CXR in detecting emphysema (96% vs. 68%). There was CT evidence of emphysema in 69% (24/35) of patients who did not have functional findings of emphysema. In 12 pathologic specimens available for review, 11 had emphysema by CT and pathologic examination; one patient had centrilobular emphysema undetected by CT. We conclude that CT is as sensitive as PFT in detecting emphysema and more sensitive than conventional radiography. CT may be more sensitive than PFT in detecting mild emphysema.(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of dual-energy digital radiography and screen-film imaging in the detection of subtle interstitial pulmonary disease.

An ROC study is described which compares the performance of three types of images--conventional screen-film, single-energy digital and dual energy bone cancelled (soft tissue) digital--in detecting subtle interstitial pulmonary disease. Marginally detectable nodular and reticulonodular patterns (12 different patterns of each) were superimposed over the lungs of a frozen human chest phantom to simulate the clinical situation. The digital images were formatted on film at full size (ie, 35 cm X 43 cm). A total of 156 images (52 of each type, of which 28 were normal and 24 had simulated pathology) were used in the study and read by five experienced chest radiologists. Using a paired t-test, the areas under the individual ROC curves were compared for three combinations of images--single-energy digital and conventional, soft tissue digital and conventional, and soft tissue and single-energy digital. No statistically significant difference was observed between the conventional and single-energy digital images. The readers performed better with both conventional and single-energy digital images than with the soft tissue digital images at statistically significant levels (P = 0.05 for conventional vs. soft tissue digital and P = 0.02 for single-energy digital vs. soft tissue digital). The results suggest that there is no advantage in employing dual-energy soft tissue images to assist in diagnosing interstitial disease in the clinical setting. They also suggest that spatial resolution requirements are less demanding in digital chest systems that obtain scatter-free images than in digital systems utilizing conventional scatter control techniques.

Overriding atrioventricular valves. An angiographic-anatomical correlate.

An analysis of 6 patients with overriding atrioventricular valve was performed in order to correlate the anatomic and angiographic features of this malformation. The atrial arrangement was usual (situs solitus) in each patient. The ventricular chambers were normally related in 4 and the mirror image of normal in 2. The atrioventricular connexion was concordant in parallel fashion in 4, discordant in 1 and double inlet left ventricle in 1 heart. In 2 of 4 hearts with concordant atrioventricular connexion, the right atrioventricular valve (tricuspid) overrode the septum and connected partially to the left ventricle. In 2, the left atrioventricular valve (mitral) overrode the septum and partially connected with the right ventricle. One heart with discordant atrioventricular connexion had its right atrioventricular valve (mitral) overriding the septum. The remaining heart with double inlet left ventricle had an overriding left atrioventricular valve. Each overriding atrioventricular valve had its "septal" leaflet (the one committed to the contralateral ventricle) divided into 2 segments by a large cleft. Ventricular septal defects at different locations were present in all cases. The ventriculoarterial connexion was double outlet right ventricle in 5 patients and was discordant in 1. Malalignment of the atrial and ventricular septa was present to some degree in all cases. This was well depicted on ventriculograms in four chamber view in those with an overriding tricuspid valve. It was not detected in those with an overriding mitral valve. The displaced leaflets of the overriding and/or stradding valve had a vertical motion on cineangiograms similar to those observed in atrioventricular septal defects. Abnormal morphology and motion of the septal leaflet of the overriding atrioventricular valve and malalignment of the atrial and ventricular septal structures were the most important angiographic findings in this series.

Persistent truncus arteriosis associated with interruption of the aortic arch.

Five patients with a combination of truncus arteriosus and interruption of the aortic arch are reported. The combination of those defects significantly increases the surgical risk. This rare cardiac malformation can only be diagnosed radiographically. An aberrant right subclavian artery is present in 25% of patients. It is helpful in suspecting the diagnosis from plain films of the chest. The diagnosis can be made from a ventriculogram, but usually a truncogram is necessary to define the anatomy of the aortic arch.

Angiographic appearance of post-operative aortic valvar stenosis. Angiographic and haemodynamic correlation.

The classic angiographic appearance of a stenotic aortic valve is that of "dooming". Adequate relief of the obstruction can be obtained with an aortic valvotomy. It should be stressed, however, that even in the absence of an haemodynamically significant gradient, "dooming" of the aortic valve persists over many years and is explained by the presence of an anatomically bicuspid valve.

Percutaneous needle biopsy of lung nodules following failed bronchoscopic biopsy.

Though transthoracic needle biopsy (TNAB) is a well established method for obtaining pathologic diagnosis in lung masses, very often the procedure is only performed after a previous negative bronchoscopic biopsy (BB) attempt. In this study we analyzed the results of TNAB in 129 consecutive patients where one or more inconclusive BB had been performed. TNAB was diagnostic in 115 of 129 lesions (89%) and the yield was not significantly affected by size, cell type or tumour location. In 97 patients who underwent thoracotomy, cytologic specimens obtained by TNAB accurately reflected histologic tumour type in all cases. A false negative rate for malignancy on TNAB was 5%. Awaiting inconclusive BB results caused an average delay of three in-hospital days before TNAB. In those patients in whom a biopsy is warranted, TNAB is most useful as an initial diagnostic procedure in masses that are peripheral and in pleural based tumours, in mediastinal adenopathy associated with a lung mass and instead of a repeat, previously failed bronchoscopy.

Doming of the pulmonary valve after valvotomy.

Doming of the pulmonary valve is considered an important angiographic sign for valvar stenosis. But, this sign cannot be used with similar specificity following valvotomy because at the time of surgery a bicuspid valve is created. Pre- and postoperative hemodynamic data and right ventriculograms are reviewed in 22 patients with simple pulmonary valvar stenosis. There was no correlation between the transvalvar gradient and appearance of the pulmonary valve after surgery.

Noninvasive localization of the aortic arch in infants with tracheoesophageal fistula: an experimental study.

For surgical treatment of patients with tracheoesophageal fistulas the localization of the aortic arch is great practical importance. Aortography and CT scanning have been advocated as the radiographic techniques of choice. The location of the aortic arch can be diagnosed on a chest x-ray by the deviation of the trachea alone. A barium swallow is not required. The optimal radiographic technique for this purpose was investigated in phantom studies and tested in animals and newborns. It is proposed that in addition to the standard chest x-ray a high kvp film with hardened beam (1 mm copper -- 1 mm aluminum) be added in order to demonstrate the tracheal deviation. The additional x-ray exposure to the infant is negligible; and the technique is simple, reliable, and noninvasive.

Coarctation of the abdominal aorta.

Coarctation of the abdominal aorta is an uncommon process but an important cause of systemic hypertension. Angiography is the investigation of choice to establish a diagnosis and document the extent of involvement. However, angiography does not provide an etiological diagnosis; and it may not be possible to distinguish an acquired coarctation from a congenital process. Three patients with coarctation of the abdominal aorta are presented.

Nonsurgical removal of intravascular foreign bodies.

With increasing use of indwelling venous catheters, embolization of intravascular catheter fragments has become a well-known complication. Because of the high risk and serious complications, embolized fragments should be retrieved whenever possible. Four cases of successful nonsurgical percutaneous catheter retrieval (two adults and two children) are described using a wire loop and a hook-shaped catheter technique. The method described allow a safe and rapid retrieval and should always precede surgical exploration.

Acquired diseases of aberrant subclavian arteries.

The anatomic, clinical, and radiologic findings of aberrant subclavian arteries (ASAs) are well known. Acquired diseases such as aneurysms, dissections, or stenosis can complicate these anomalies. We propose that these complications are a result of atherosclerosis caused by abnormal turbulence around the ASA. Comparisons of computed tomographic and angiographic measurements of subclavian arteries in adults with and without arch anomalies and angiographic measurements of ASAs in children show that ASAs dilate in older patients. We describe six patients with acquired diseases of ASAs or the aorta adjacent to the ASA. Aneurysms, aortic dissections, and stenosis were each found in two patients. Problems in the radiologic diagnosis and clinical management of these diseases are emphasized. Radiologists should be cognizant of the significance of ASAs in patients with aortic aneurysms and dissections.

Preoperative evaluation of bronchiectasis by computed tomography.

A patient with known lingular bronchiectasis is presented for whom CT was used as the sole preoperative radiographic method to exclude disease in the remainder of the bronchial tree. The patient has remained symptom free for 12 months following lingulectomy. The potential of CT to obviate the need for bronchography in the preoperative staging of bronchiectasis is discussed.