Detection of metastases from differentiated thyroid cancer by different imaging techniques (neck ultrasound, computed tomography and [18F]-FDG positron emission tomography) in patients with negative post-therapeutic ¹³¹I whole-body scan and detectable serum thyroglobulin levels

INTRODUCTION

DTC patients having detectable Tg and negative post-therapeutic (131)I-WBS have to be investigated by different imaging techniques to detect metastases.

PURPOSE

Comparison of neck US, CT and [18F]-FDG PET scan.

METHODS

In 49 DTC patients with biochemical disease, neck was examined by US, CT and [18F]-FDG PET. FNA was performed and Tg was determined by FNA-Tg in selected cases of suspicious lymph nodes. Thorax was examined by CT and PET. Serum Tg was measured on LT4 therapy (basal Tg) and after the stimulation with recombinant human TSH (peak Tg).

RESULTS

A thyroid remnant was seen by US, CT and PET in eight patients; recurrences were seen by US, CT and PET in six, five and five patients, respectively. Two metastatic nodes were identified by US and CT but not by PET. Lung micronodules were detected by CT in 7/49 (14.3 %) patients and by FDG PET in three of them. Basal Tg ranged from 0.5-1,725 ng/ml while peak Tg ranged from 0.5 to 2,135 ng/ml: the distribution between positive and negative patients was similar. Bone scan was negative in all cases.

CONCLUSIONS

In DTC patients with detectable Tg and negative I-131 post-therapy WBS, imaging examination revealed remnant or metastases in 43 % of cases. Remnant and recurrences were equally detected by the three techniques; US was better than [18F]-FDG PET for lymph node metastases since this latter method can give false both positive and negative results; chest examination is best made by CT versus FDG PET due to its higher spatial resolution.

Determinants of the prognosis of idiopathic pulmonary fibrosis

OBJECTIVE

Fibrotic idiopathic interstitial pneumonias are chronic and progressive lung diseases with different prognosis, with idiopathic pulmonary fibrosis (IPF) having the worst prognosis. Many patients need a surgical lung biopsy for the definite diagnosis of IPF but age and the clinical context often contraindicate this procedure. The aim of this study is to identify predictors of survival, apart from lung biopsy, in patients with definite and possible IPF.

PATIENTS AND METHODS

We studied 42 patients with HRCT pattern of definite or possible IPF, by assessing the mortality in relationship with baseline HRCT and functional findings. HRCT was assessed both as prevalent pattern (definite vs possible UIP) and as score of the different abnormalities (in particular, honeycombing (HC) and total fibrotic score). Pulmonary function was assessed as baseline FVC, TLC and DLCO values, as well as change over 6 months of follow-up. Both univariate and multivariate analyses were performed in order to detect predictors of mortality.

RESULTS

During follow-up, 10 out of 42 patients died. Mortality rate was not different according to the qualitative pattern of fibrosis at HRCT. Among the different HRCT scores, a cut-off of 15% in the HC score differentiated patients with higher mortality rate. A lower baseline FVC, and a greater decrease in pulmonary function after 6 months, were both associated with higher mortality. In a logistic analysis taking in consideration clinical, radiological and functional findings, only baseline FVC and FVC change after 6 months resulted significant predictors of mortality.

CONCLUSIONS

Functional evaluation at the baseline and during follow-up is more relevant than HC score for the prognosis of patients with definite and possible IPF.

[The ictal bradycardia syndrome: a case report and review of the literature]

Epilepsy is a rare cause of sinus node dysfunction which should be recognised. The authors report the case of a 55 year old woman with refractory epilepsy who had sinus arrest during her epileptic fits. After excluding a possible interaction by long-term Carbamazepine treatment, the diagnosis of the Ictal bradycardia syndrome was made in view of the simultaneous occurrence of severe bradycardia and epileptic activity recorded on electro-encephalography. Sudden death being more common in epilepsy, effective treatment of conductive cardiac abnormalities is essential. The refractory nature of the epileptic fits led to the implantation of a permanent pacemaker in this case.

[Usefulness of B-type natriuretic peptide (BNP) for the diagnosis of new-onset heart failure with a preserved left ventricular systolic function in longstanding hypertensive patients with acute dyspnea]

BACKGROUND

B-type natriuretic peptide (BNP) has been largely validated in the etiologic diagnosis of acute dyspnea. Nevertheless, its reliability in the setting of a preserved left ventricular systolic function (ejection fraction >50%) has not been adequately established.

OBJECTIVE

the study addressed the usefulness of BNP in the diagnosis of new-onset heart failure with a preserved systolic function in hypertensive patients hospitalized for acute dyspnea.

METHODS

59 consecutive hypertensive patients without history of heart failure and coronary disease were included. BNP was measured at presentation with the Triage system. Noninvasive estimation of left ventricular filling pressures by bedside tissue Doppler echocardiography at presentation was incorporated in the diagnostic criteria.

RESULTS

the 30 patients with heart failure were not significantly different from the 29 patients with noncardiac cause of acute dyspnea regarding age, gender, body mass index and ejection fraction. Median levels of BNP were significantly higher in heart failure (447 [245-644] versus 87 [43-139] pg/mL). By multivariate logistic regression analysis, BNP (odds ratio of 44, [3.6-531], p=0.003) provided independent and incremental diagnostic information over the clinical score of Boston criteria (2.25, [1.3-3.9], p=0.0037). A BNP value of >142 pg/mL (area under the ROC curve of 0.89, p<0.0001) was 93 sensitive and 79% specific for the diagnosis of heart failure in this setting.

CONCLUSION

BNP is a reliable biomarker of new-onset heart failure with a preserved systolic function in hypertensive patients, in particular older, hospitalized for acute dyspnea and can be safely integrated in the diagnostic strategy.

[Prognostic value of BNP for hospital mortality in elderly subjects hospitalised for acute diastolic cardiac failure]

The aim of this study was to evaluate the prognostic value of BNP in elderly patients hospitalised for acute diastolic cardiac failure. 108 consecutive subjects were included, aged at least 70 years old, hospitalised for isolated acute diastolic cardiac failure. All of them had a left ventricular ejection fraction > or = 50% and evidence of diastolic dysfunction on echocardiography performed shortly after admission. The plasma BNP concentration measured in the emergency department on admission was >100 pg/ml in all of the patients except five. It was positively correlated with age (R = 0.29, p = 0.002), with the plasma creatinine level (R = 0.37, p < 0.0001) and the plasma urea level (R = 0.41, p < 0.0001). On univariate analysis, compared to the patients who survived, the 20 patients who died before discharge were significantly older (88.6 versus 84.4 years, p = 0.01), and were more often residents of a care home (60 versus 31%. p = 0.02), had a lower systolic blood pressure on admission (127 +/- 33 versus 154 +/- 30 mm Hg), a higher plasma urea level (16.8 +/- 12 versus 8.9 +/- 5 mmol/l, p = 0.002) and a higher BNP (median = 1290 pg/ml, interquartile range: 721, 3026 pg/ml versus 430 pg/ml, interquartile range: 243, 886 pg/ml). On multivariate analysis, the only factors that remained significantly associated with mortality were the BNP levels (p = 0.005) and the systolic blood pressure (p = 0.01). The negative predictive value of a BNP level < 631 pg/ml (median) for death was 94% (95% confidence interval: 91 to 97%). We conclude that BNP does have an independent prognostic value for in-hospital death in elderly subjects with acute diastolic cardiac failure.

[Remodelling in atrial fibrillation]

It is well known that atrial fibrillation (AF) tends to become permanent with time as illustrated by the fact that it becomes more difficult to maintain sinus rhythm when AF has been present for a long time. Atrial remodelling plays a part in this process and has been studied in experimental models. Atrial remodelling is defined as all the phenomena occurring during AF contributing to its maintenance. The persistence of AF induced by stimulation in the animal depends on the duration and the repetition of the atrial stimulation and it would appear that "AF induces AF". The tendency for AF to persist is associated with a shortening of the effective atrial refractory period with loss of its adaptation to the heart rate. The determining factor of both electrical and structural remodelling is the rapidity of the atrial rhythm of the AF itself. These phenomena lead to a type L calcium cellular overload as shown by its prevention or attenuation by the administration of verapamil, a calcium antagonist. Electrical remodelling is accompanied by a structural remodelling in the experimental model of persistent AF over several weeks. Samples from the two atria examined by electronic microscopy show mitochondrial changes, an accumulation of glycogen, a deficit in myofibrils, a redistribution of the nuclear chromatim and a reduction of sarcoplasmic reticulum with changes in protein structure. This structural remodelling is a reaction of adaptation similar to that observed in hibernating myocardium during ischaemia and aims to prolong cellular viability by decreasing atrial contractility. Another aspect of structural remodelling is the activation of fibroblasts with formation of fibrosis with resulting heterogeneity of the conduction tissue. There is also an increase in converting enzyme and angiotensin II concentrations. Irbesartan, an angiotensin II antagonist, reduced fibroblast growth. This has clinical applications as shown by the reduction in the recurrences of AF after cardioversion when given in association with amiodarone. Persistent AF leads to left atrial dilatation with abnormal atrial contractility. Further studies are necessary to determine the effect of atrial remodelling which might also act on the foci responsible for inducing the AF. Better understanding of atrial remodelling will contribute to the use of new pharmacological agents to prevent AF.

Manifestations et risques cardiovasculaires des dysthyroïdies infracliniques

PURPOSE

To clarify the importance of cardiovascular symptoms and risks in subclinical dysthyroidism in order to define the best way of treatment and follow-up.

CURRENT KNOWLEDGE AND KEY POINTS

Subclinical dysthyroidism is defined by abnormal circulating TSH values in face and normal free thyroid hormones levels, in asymptomatic individuals. If the cardiovascular effects of overt hyperthyroidism are well documented, the relation between subclinical dysthyroidism and the heart is not well established. Subclinical hyperthyroidism may be caused by the same thyroid disorders that results in overt hyperthyroidism, but the most common cause is excessive dosage in levothyroxine. The most frequent cardias complication of subclinical hyperthyroidism is atrial fibrillation. Recently minimal alterations of myocardial function have also been described. In most patients, one tries to return to euthyroidism in order to prevent cardiovascular complications. Subclinical hypothyroidism is 3 to 10 times more frequent, especially in women after 60 years. Subtle modifications of cardiac function and lipid metabolism and an increased risk of atherosclerosis have been described in this condition. There is still debate about the decision to treat or not to treat these patients.

FUTURE PROSPECTS AND PROJECTS

Until now, treatment of subclinical dysthyroidism is mainly based upon experiences and convictions to physicians. Prospective studies are necessary to assess the true benefits and risks of either early treatment or therapeutic abstention with regular clinical and biological follow up. In such studies, patients should be separated according to age and the nature (endogenous or exogenous) of dysthyroidism.

Right atrial sensing for VDD pacing through a persistent left superior vena cava

This report describes a pacing lead insertion through a persistent left superior vena cava in the VDD pacing mode, with a large retrograde lead course allowing the optimal positioning of the sensing electrodes in the right atrium.

Hypothalamo-pituitary-adrenal axis in acute myocardial infarction treated by percutaneous transluminal coronary angioplasty: effect of time of presentation

Acute myocardial infarction (AMI) is associated with a stimulation of cortisol which lasts 24 hours in patients treated by thrombolysis. Percutaneous transluminal coronary angioplasty (PTCA) is an alternative treatment for AMI which reduces the length of myocardial ischemia. Our objective was the determination of the amplitude and duration of cortisol and other hormones of the hypothalamo-pituitary-adrenal (HPA) axis release in patients undergoing PTCA. These responses were also analyzed in relation with the time of onset of AMI. The effect of coronarography with or without angioplasty in patients without AMI was also studied. Plasma ACTH, cortisol, corticotropin-releasing hormone and arginine vasopressin levels were determined during the first 48 hours in 20 patients with first AMI, treated by PTCA and in 10 patients without AMI undergoing coronarography (and angioplasty in five of them). A strong stimulation of the HPA axis was observed in AMI patients, but the duration of cortisol secretion was significantly reduced (less than 8 hours) as compared with previous studies in patients treated with thrombolysis. A clear-cut ACTH-cortisol dissociation was also observed after the third hour. ACTH and cortisol stimulation was higher in patients admitted between 04:00 h and 16:00 h than in patients admitted between 16:00 h and 04:00 h In patients without AMI, coronarography induced a moderate, but significant short-lasting ACTH and cortisol stimulation. In conclusion, our data suggest that the degree of stimulation of the HPA axis may depend upon the type of treatment and the circadian rhythm of this axis.

[Mitral insufficiency related to a spasm of the left anterior descending artery. A case report]

We report the case of a female patient of 76 years old admitted to our hospital for a pre-operative assessment of a symptomatic mitral regurgitation (MR) whose transthoracic echocardiography revealed only a trivial regurgitation. The occurrence during hospital stay of an acute pulmonary edema contemporary to the occurrence of a huge MR permitted to suspect the diagnosis of a paroxystic ischemic MR. Angiographic and hemodynamic evaluation revealed only a non-significant atheromateous plaque located in the distal LAD. The infusion of Methylergometrine triggered a severe spasm at the site of that plaque, associated with a huge MR visualized by TTE with restricted movements of both leaflets, responsible for an acute pulmonary edema occurring on the table of the catheterization laboratory. Recovery was quickly obtained after intravenous injection of Nitroglycerin, which removed the spasm and valvular regurgitation. The diagnosis of paroxystic ischemic mitral regurgitation was confirmed and a treatment based on high dosage of calcium-blocker was decided. After a follow-up of more than one year, the patient remains asymptomatic and the regurgitation has never occurred.

[Cardioversion by external electric shock for atrial fibrillation: does patient age affect immediate results?]

The restoration of sinus rhythm by external electric shock in patients with persistent atrial fibrillation is a well established treatment. However, in current practice this treatment is generally indicated less in the elderly subject although this attitude is not factual. The objective of this work was to evaluate the immediate results of cardioversion by external electric shock, comparing the success rates in four age groups: under 60 years, between 60 and 69 years, between 70 and 79 years, and over 80 years. This study was performed on 182 consecutive patients aged from 25 to 89 years: 35 patients aged less than 60 years, 52 patients aged from 60 to 69 years, 65 patients aged from 70 to 79 years, and 30 patients aged 80 years or over. The success rates were 91.4% before 60 years, 90.4% between 60 and 69 years, 90.8% between 70 and 79 years, and 83.3% after 80 years. There was no significant difference between the success rates in the four age groups (p = 0.68). Among the other factors analysed, only the duration of atrial fibrillation and the body mass index significantly influenced the results of external electric shock in this series. This work suggests that age does not significantly influence the immediate results of external electric shock. According to these data it does not appear justified to contra-indicate cardioversion by external electric shock on the sole criterion of age.

[CT virtual angioscopy in the study of thoracic aortic dissection]

PURPOSE

Virtual endoscopy is a technique in which helical-CT and MR data sets are processed by a special software creating a three-dimensional viewing of the inner surface of hollow viscera that simulates the endoscopic view. We report our 2.5-year experience with virtual intraluminal endoscopy (VIE) in the study of the thoracic aorta in patients with aortic dissection and in patients with normal aorta.

MATERIAL AND METHODS

From December 1997 to June 2000, CT angiography (CTA) data sets of the thoracic aorta obtained in a series of 43 patients were retrospectively evaluated. Our series included 23 patients with clinical or radiological suspicion of aortic dissection and 20 patients in whom the study of the thoracic aorta was carried out as a necessary completion of an abdominal aortic disease. CTA data sets were processed with a dedicated software (Navigator); the view point and view direction could be set arbitrarily in the vessel, obtaining an intraluminal endoscopic view of the inner surface of the vessel. Multiple views were obtained and visualised consecutively through a cine-loop technique. The entire thoracic aorta was studied.

RESULTS

VIE enabled correct visualisation of the intimal flap in all cases of aortic dissection (=23) and of its origin at the level of the ascending aorta in 16 cases (Stanford A) and in the descending aorta in the remaining 7 patients (Stanford B). In the control group (=20) no signs of intimal flap were identified with the VIE. In all patients with aortic dissection false and true lumen were entirely visualised. VIE allowed the understanding of the relation between false lumen and supraaortic vessels that originated from the true lumen in all cases and were found to be dissected in 6 patients. In 16 cases the dissection included thoracic and abdominal aorta. In some cases the endoscopic view was altered by artifacts related to the selected threshold levels and represented by pierced surface and floating shape artifacts. A correlation with axial and multiplanar (MPR) images allowed the correct interpretation of such artifacts.

CONCLUSIONS

According to our experience, virtual endoscopy represents a useful tool in the evaluation of the dissection of the thoracic aorta, allowing a better definition of anatomical details. A correlation with axial images and multiplanar views remains compulsory for a better understanding of VIE findings, which is nevertheless significantly influenced by the operator's experience.

Functional significance of the decreased attenuation sign on expiratory CT in pulmonary sarcoidosis : report of four cases

We describe four patients with proven sarcoidosis and minor pulmonary involvement according to high-resolution CT (HRCT) findings in whom the recently described sign of decreased attenuation on expiratory HRCT scan appeared associated with the reduction of the single-breath diffusing capacity of the lung for carbon monoxide (DLCO) and the DLCO adjusted for alveolar volume. These alterations were, in part, reversible under steroid treatment. Major indexes of airway obstruction (FEV(1)/vital capacity ratio and FEV(1)) were normal, while the maximum expiratory flow at 25% above the residual volume of FVC was reduced. These observations suggest that an expiratory HRCT mosaic pattern and diffusion impairment may be early findings in pulmonary sarcoidosis and may be useful for its detection and follow-up.

[Validation of quantitative parameters of paraprosthetic mitral valve regurgitation of the zone of convergence by transthoracic echocardiography]

The study of the convergence zone by echocardiography is a validated method of quantification of native valve mitral regurgitation. However, there is little data concerning its applications to paraprosthetic mitral regurgitation. The aim of this study was to evaluate the method in this indication. Thirty consecutive patients (21 mechanical and 9 bioprostheses) with paraprosthetic mitral regurgitation quantified by transoesophageal echocardiography were included: 4 mild, 13 moderate and 13 severe. The regurgitant volume RV) and the regurgitant surface area (RSA) were calculated by the following formulae: RV = 2 pi.r2.Va.t.alpha/180 and RSA = RV/VTI (r: mid systolic radius of the convergence zone, Va: aliasing velocity, t: regurgitation time, alpha/180: the angular correction due to parietal stress, VTI: velocity time integral of the regurgitant flow). The feasibility of the calculation of the RV and RSA was 93 and 63% respectively. There was a statistically significant correlation between the RV and transoesophageal echocardiography (r: 0.85, p < 0.001), between RSA and transoesophageal echocardiography (r: 0.67, p < 0.05) and between RV and RSA (r: 0.95, p < 0.001). When severe paraprosthetic regurgitation was defined by a RV greater than 60 ml and RSA greater than 40 mm2, the concordance between RV, RSA and transoesophageal echocardiography was 75% and 74% respectively. Therefore, the study of the convergence zone provides an accurate evaluation of paraprosthetic mitral regurgitation by transthoracic echocardiography.

[Tolerance and efficacy of carvedilol prescription in patients with mild to moderated chronic heart failure]

The current treatment for heart failure, i.e., carvedilol administration, has brought about a significant reduction in cardiovascular morbidity and mortality. The European Cardiology Association task-force has recently recalled that the treatment for heart failure should be considered differently according to the regions within Europe. However, most studies have involved North American or Australasian subjects. The results of these studies have shown that carvedilol improves the symptomatic status of patients with mild to moderate chronic heart failure, but their extrapolation to the situation in Europe is questionable. In the present study, the authors have reported on the use of this beta-blocker over a 6-month period in 48 European subjects (an older patient population, and more frequently given digitalis treatment) with mild to moderate stage II and III chronic heart failure (mean NYHA functional stage = 2.75 +/- 0.2; mean left ventricular ejection fraction = 32.4 +/- 3.4). Six patients (12.5%) were obliged to withdraw from the study due to adverse reactions to carvedilol, i.e., 2 subjects during the test-dose (4.2%) and 4 others who were subsequently unable to withstand the progressive stepping up of drug dosage (8.3%). In the remaining 42 patients, the mean NYHA scores dropped significantly from 2.75 +/- 0.2 to 1.8 +/- 0.1 (p < 0.05) at the end of the study period, indicating an increase in symptomatic improvement with a favorable hemodynamic tolerance profile, even in cases of combined therapy with digitalis. This study confirms the positive action of carvedilol on functional symptomatology in southern European patients presenting with mild to moderate chronic heart failure. However, it should be emphasized that this beta-blocker should only be administered under strict and specialized medical surveillance as its effect of significantly slowing down the heart rate could also result in cardiac insufficiency.

Virtual CT intravascular endoscopy of the aorta: pierced surface and floating shape thresholding artifacts

Two types of artifacts may appear in virtual computed tomographic endoscopic views of the aorta rendered at different threshold levels: pierced surface and floating shape artifacts. A positive correlation was found between mean attenuation of the aorta and the threshold levels at which these artifacts appeared. The correlation was statistically significant (0.71 < or = r < or = 0.86) for floating shape. An artifact-free threshold range can be predicted on the basis of aortic enhancement.

[Study of bullous fibrosis of the upper lobes in ankylosing spondylitis with high-resolution computerized tomography]

The fibrobullous disease of the upper lobes is an uncommon extraspinal complication of ankylosing spondylitis. We report the conventional radiographic and High Resolution Computed Tomographic (HRCT) findings in the fibrobullous disease of the upper lobes in ankylosing spondylitis. From 1988 to 1994, four patients affected with ankylosing spondylitis, with radiographic involvement of the upper lobes, came to our observation. All patients underwent a chest X-ray exam and the previous chest X-rays carried out 2-25 years earlier were reviewed. Within 15 days, HRCT was performed, during inspiratory apnea. In all cases, repeated bronchoscopies were available, showing bronchial inflammation, together with cytologic tests and bronchial fluid cultures, which revealed no development of mycobacterium tuberculosis. The most frequent CT findings were pleural thickening, fibrotic consolidation and thickening of interlobular septa. Bullae, nodules and ground-glass areas were less frequent findings. The standard chest X-ray exam demonstrated, with the same sensitivity as HRCT, pleural thickening, bullae, nodules and volume loss in the involved lung. However, interlobular septa thickening was depicted only in one case, while bronchiectases and ground-glass areas were not recognized at all. Three temporally distinct patterns of apical involvement (infiltrative, interstitial and fibrobullous) were identified. In conclusion, HRCT was more sensitive and more specific than chest X-rays in the study of the fibrobullous disease of the upper lobes in ankylosing spondylitis.

[Diagnostic imaging of intestinal invaginations in the adult. Report of 9 cases]

Adult intestinal intussusception affects the distal portions of the small bowel and the colon in 90% of cases. As a rule, its nature is neoplastic, its clinical presentation aspecific and its diagnosis is frequently an occasional finding during routine imaging examinations. We report on 9 adult patients with intestinal intussusception. All patients were examined with more than one of the following imaging modalities: radiologic study of the small bowel, barium enema, ultrasonography (US), and Computed Tomography (CT). The first diagnostic suspicion of intussusception was correctly made at US in 5 patients and at CT in 4 patients. At surgery, intussusception sites were the following: jejunum in one case, ileum in two cases, ileocolon in two cases and colon in four cases. CT correctly detected lesion site in all the patients who underwent it as the first diagnostic step, while US missed lesion site in one case. Pathology diagnosed a hamartomatous jejunal polyp, a lymphomatous ileal polyp, a lymphomatous polyp of the ileocecal valve, four cecocolonic adenocarcinomas and a left colic lipoma. Lesion nature was suspected at US in one case of ileal lymphoma, while CT suggested the presence of lipoma in one case of ileoileal intussusception. Our experience shows that intussusception can be diagnosed not only with conventional radiologic modalities, but also with US and CT, which are useful to depict both the lesion and its site and extent.

Laparoscopic sonography in screening metastases from gastrointestinal cancer: comparative accuracy with traditional procedures

The wide use of operative and diagnostic laparoscopy has led to a greater use of the laparoscopic ultrasound (LUS) as a complementary procedure. A preliminary study was performed to evaluate the efficacy of LUS using a linear array laparoscopic probe characterized by double frequency, mechanical flexibility, and availability of Doppler analysis. LUS was performed in 36 patients with gastrointestinal neoplasms and compared with preoperative sonography, computed tomography, and with laparoscopy alone. LUS identified liver metastases with a sensitivity of 100% versus 60% for preoperative diagnostic means and laparoscopy. Nodal metastases were identified with a sensitivity of 96.1% and a specificity of 66.6%. Therapeutic planning was modified as result of LUS in 8 of 35 cases (22.9%). In patients with abdominal malignancy, LUS improves staging (cancer spread, nodal metastases, liver metastases), modifying therapeutic decisions. LUS represents a complementary, indispensable diagnostic method during laparoscopic surgery.

CT evaluation of chronic thromboembolic pulmonary hypertension

Eight patients with chronic thromboembolic pulmonary hypertension (CTPH) that had been demonstrated by perfusion lung scan, pulmonary arteriography, and right heart catheterization had their pulmonary circulation evaluated by CT. Eight subjects without lung pathology were also studied for comparison. High resolution CT from apex to base with 1 cm thick sections after intravenous injection of contrast medium was performed in each individual. Emboli lodged in main pulmonary arteries on arteriography were regularly shown by CT, whereas those in segmental or smaller arteries were not detected. Diameters of the main pulmonary arteries measured on CT correlated with systolic pulmonary artery pressure (p < 0.001). The ratio between diameters of segmental arteries and the corresponding bronchi (A/B ratio) on CT was > 1 in 72 of 144 examined pulmonary segments (18 segments for each patient) in patients with CTPH. The ratio was > 1 in only 10 of 144 examined segments in normal control subjects. Dilatation of bronchial arteries was present in four of eight patients with CTPH. The parenchymal density in patients with CTPH was significantly higher in the axial than in the middle or peripheral lung compartments. In conclusion, CT may help with the diagnosis of CTPH by detecting thrombi of main arteries and by showing characteristic findings; moreover, it is accurate in estimating pulmonary arterial pressure secondary to thromboembolic obstruction.

[Calcaneal fractures: CT aspects]

Calcaneal fractures account for 33.3% of foot fractures and 1.5% of all fractures. They were divided by Warrick and Brenner into two main groups according to whether they modify the astragalocalcaneal joint or not. Given the anatomical complexity of the foot, conventional X-rays are not always able to correctly visualize the articular facets and therefore provide insufficient information as to the characteristics of the fracture line, the position of bone fragments, and the involvement of capsulo-ligamentous structures. The authors report their personal experience with CT in the study of 12 patients with monolateral calcaneal fractures previously diagnosed on conventional X-rays. High-resolution CT (HRCT) was employed with 3-mm contiguous sections on the axial and the coronal planes. CT was used to study the normal anatomy of the foot and to evaluate 3 patients with calcaneal fracture without impaction of the posterior facet; 9 patients with impaction into the calcaneal body were also examined with CT. In the first 3 cases, an oblique fracture line was observed crossing from craniolateral to mediocaudal and thus dividing the calcaneus into 2 large fragments: sustentaculum tali and posterior facet of the talar joint. In the extant 9 cases the impaction of the posterior facet was indicated by an interruption in lateral and/or medial calcaneal walls. In 2/9 cases bone fragments were seen in the tarsal sinus, in 4/9 the sustentacular fragment was displaced, in 2 the cuboid bone was impacted into the anterior process of the calcaneus and, finally, in 7/9 cases a lateral/medial dislocation of the calcaneal tuberosity was observed. On the basis of these results, CT proved to be of greater value than conventional X-rays in the imaging of calcaneal fractures and to have a fundamental role every time an accurate evaluation of the region is needed to plan treatment.

[Up-to-date computed tomographic findings on the para- and perirenal spaces under normal and pathologic conditions]

The anatomy of the peri- and pararenal spaces was critically reviewed, supported by high-definition CT images. In the past, CT did not allow the visualization of such structures as the perirenal septa. Nowadays, on the contrary, such anatomical structures can be demonstrated, which allows their involvement to be monitored in pathologic conditions. The perirenal septa appear thus to prevent fluid collections from spreading, while they seem to be the preferential pathways for the diffusion of malignant lesions.