Andrzej Drop

Changes in cerebral hemodynamics after carotid stenting: evaluation with CT perfusion studies

PURPOSE To determine changes in cerebral perfusion parameters, based on CT perfusion imaging, in patients after unilateral transluminal angioplasty and stent placement. MATERIAL AND METHODS 74 patients with symptomatic high - grade internal carotid artery stenosis (>70%) were studied with CT perfusion imaging before and - on average - 70 hours and 172 days after carotid stent placement. There were 50 patients with unilateral carotid artery stenosis and 24 with stenosis and accompanying contralateral internal carotid artery occlusion. CT examination was performed using a multidetector helical CT scanner (Light Speed Ultra Advantage, GE Healthcare, USA). Maps showing the absolute values of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) were generated. RESULTS In a group with unilateral carotid artery stenosis perfusion deficits were present in 84% of patients, ipsilaterally to stenosis. MTT elongation was noted (6.2-6.8s) together with decreased values of CBF (40-46ml/100g/min) and slightly increased CBV (3.2ml/100g). In this group, 3 days after stenting, 30% of patients had perfusion deficits, and after 6 months only 6%. In a group with carotid artery stenosis and contralateral artery occlusion severe perfusion deficits were noted in both hemispheres and they were present in 100% of patients. 6 months after stenting hypoperfusion was observed only in 17% of patients. CONCLUSIONS Brain perfusion deficits, observed in a majority of patients with carotid artery stenosis tend to improve considerably after carotid artery stenting, in long - term follow up.

Squamous cell cancer of hypopharynx and larynx – Evaluation of metastatic nodal disease based on computed tomography perfusion studies

BACKGROUND AND PURPOSE In patients with squamous cell cancer metastatic disease in lymph nodes still remains the single most important negative predicting factor and when detected, it reduces overall 5-year survival by 50%. The aim of the study was to evaluate contrast-enhanced computed tomography (CECT) with computed tomography perfusion (CTP) examination in order to differentiate malignant from non-malignant cervical lymph nodes in patients with squamous cell cancer of hypopharynx and larynx. MATERIAL/METHODS This was a prospective three-center study. From November 2007 until March 2010 33 consecutive patients with squamous cell cancer of the hypopharynx and 27 patients with laryngeal cancer underwent computed tomography (CT) examination followed by CTP. During first part of examination 80 ml of contrast was administered, with flow rate 1 ml/s and 100 s delay; standard head and neck examination was performed. Next, perfusion images were acquired with the coverage of 8 cm and different groups of lymph nodes were evaluated - groups II, III, IV and V. Perfusion maps for basic parameters (blood flow [BF], blood volume [BV], mean transit time [MTT] and permeability surface [PS]) were reconstructed for all patients using dedicated software. The long and short axis diameters, the density of the node before and after contrast medium administration and average values of each perfusion parameter were calculated for every node separately. Results were compared with histologic analysis of resected nodes. RESULTS Out of the total number of 293 nodes evaluated on CECT and CTP it was possible to correlate 208 resected nodes with histologic findings. 125 of them were proven to be malignant and 83 were benign. Malignant nodes showed remarkably higher density and hyperperfusion, comparing to benign ones. The average density values in Hounsfield units (HU) for cervical nodes were: 91.9HU for metastatic comparing to 72.3 HU for non-metastatic, but this difference did not show statistical significance. The average value of BF in malignant nodes was 136.4 ml/100g/min, BV was 7.7 ml/100g, MTT was 4.4s and PS was 19.4 ml/100g/min. The average values for benign nodes were: BF was 80.7 ml/100g/min, BV was 4.7 ml/100g, MTT was 5.6s and PS was 12.8 ml/100g/min. Comparing to non-malignant nodes, malignant ones showed significantly higher BF, BV and PS values (p<0.05). CONCLUSIONS Although CECT findings may draw our attention, pointing at abnormal morphology of the node, CTP seems to provide additional functional information regarding its possible malignancy. CTP may be useful in differentiation between malignant and benign lymph nodes, based on evaluation of the value of BF, BV and PS.

Evaluation of tracheal stenosis: comparison between computed tomography virtual tracheobronchoscopy with multiplanar reformatting, flexible tracheofiberoscopy and intra-operative findings.

The aim of the study was to evaluate and compare various helical CT display modes [virtual endoscopy (VE)] and multiplanar reformations (MPR), conventional flexible tracheobronchoscopy (FT) and intra-operative (IO) findings in patients with tracheal stenosis and to analyze the advantage of MPR and VE in diagnosis and treatment planning and in postoperative follow-up. Thirty-seven patients with tracheal stenosis underwent standard neck and chest CT followed by MPR and VE. Results were correlated with the results of FT and IO findings. Thirty-three of the 37 stenoses were correctly graded and measured adequately using VE. Complete correlation among CT, fiberoptic tracheoscopy, and surgery of stenosis grading, stenosis length and length of planned resection segment of the trachea was noted between 33 of 37 patients with tracheal stenosis. Correlation between VE and IO was noted in 35 of 37 patients and between FT and VE was noted in 33 of 37 patients with tracheal stenosis. The sensitivity of VE was 94–97%, specificity was 100% with comparison to IO findings. The sensitivity and accuracy of MPR was 86–89% and specificity was 100% with comparison to FT findings. The results of the study indicate that VE is an excellent, consistent, and objective technique. VE with MPR is very useful in diagnostic evaluation and treatment planning in patients with tracheal stenosis.

External and middle ear diseases: radiological diagnosis based on clinical signs and symptoms

ObjectivePathology of the external and middle ear is the most frequent reason to prescribe antibiotics and perform surgery in children and young adults. In the majority of cases imaging studies are not performed; the need for imaging comes when complications are suspected or when treatment is not effective. This paper discusses indications for temporal bone imaging studies and presents the most frequent pathological conditions, together with differential diagnosis, clinical symptoms and methods of treatment.Methods and ResultsThis pictorial review describes major external and middle ear diseases, with special regard to clinical findings and appropriate reporting.ConclusionsApprehension of the complete clinical picture, together with imaging clues, narrows differential diagnosis and helps avoid mistakes. Evaluation of temporal bone pathologies requires close cooperation between the clinician and radiologist.

Role of 18F-FDG PET/CT in the diagnosis of inflammatory and infectious vascular disease

This review article discusses the utility of 18F-FDG PET/CT in diagnosis and management of vascular disease. We stress usefulness of this method in large vessel inflammation and infection. In our work we based on the literature analysis and clinical cases diagnosed in our institution by use of 18F-FDG PET/CT. The literature exploration was focusing on vascular inflammation and infections and 18-FDG PET. The search was performed on PubMed database and cross referencing. We present the practical review with several images of vascular diseases like: Takayasu arteritis, giant cell arteritis, vascular graft infections, abdominal aortic aneurysm infections and cases of aortitis and periaortitis. From this work inflammation associated with atheromatic process and vulnerable atherosclerotic plaque we excluded. 18F-FGD PET/CT is a sensitive metabolic, reliable, non-invasive imaging modality suitable for diagnosis and follow-up of inflammation and infections in vascular system.

Logistic regression model for identification of right ventricular dysfunction in patients with acute pulmonary embolism by means of computed tomography

PURPOSE Diagnosis of right ventricular dysfunction in patients with acute pulmonary embolism (PE) is known to be associated with increased risk of mortality. The aim of the study was to calculate a logistic regression model for reliable identification of right ventricular dysfunction (RVD) in patients diagnosed with computed tomography pulmonary angiography. MATERIAL AND METHODS Ninety-seven consecutive patients with acute pulmonary embolism were divided into groups with and without RVD basing upon echocardiographic measurement of pulmonary artery systolic pressure (PASP). PE severity was graded with the pulmonary obstruction score. CT measurements of heart chambers and mediastinal vessels were performed; position of interventricular septum and presence of contrast reflux into the inferior vena cava were also recorded. The logistic regression model was prepared by means of stepwise logistic regression. RESULTS Among the used parameters, the final model consisted of pulmonary obstruction score, short axis diameter of right ventricle and diameter of inferior vena cava. The calculated model is characterized by 79% sensitivity and 81% specificity, and its performance was significantly better than single CT-based measurements. CONCLUSION Logistic regression model identifies RVD significantly better, than single CT-based measurements.

Head and neck cancer: Value of perfusion CT in depicting primary tumor spread

Summary Background The aim of this study was to assess head and neck squamous cell cancer and surrounding tissue in computed tomography contrast enhanced and perfusion studies, and to examine the role of perfusion imaging in depiction of tissue infiltration. Material/Methods We prospectively evaluated 43 primary malignant head and neck tumors, using standard CT followed by perfusion. Blood flow, blood volume, mean transit time, and permeability values were obtained using regions of interest (ROIs) over lesions and surrounding tissue. Results were compared with histological analysis of resected tissue. Sensitivity, specificity, accuracy, positive and negative predictive values were calculated for both methods. Results We found significant differences between infiltrated and non-infiltrated tissue, especially with regard to muscles. In case of bone and salivary gland infiltration, change in perfusion parameters did not allow proper diagnosis. Conclusions CTP shows promise in depicting malignant infiltration. The combined use of CECT plus CTP results in correct staging of the majority of head and neck tumors.

Papillary fibroelastoma as an accidental finding in a multislice computed tomography scan of coronary arteries

Papillary fibroelastomas represent less than 10% of all primary cardiac tumours. They are usually incidental autopsy or surgical findings, or detected during echocardiography or catheterization. The case of a 58-year-old man with typical exertional chest pain hospitalized for an elective multislice computed tomography (MSCT) scan of the coronary arteries is described. The MSCT scan showed a pathological, mobile lesion within the aorta lumen only, not obstructing the ostia of the coronary arteries, and was confirmed by echocardiography. The typical features of the tumour in the MSCT scan and on echocardiography were the basis for the diagnosis of papillary fibroelastomas in the patient. Surgical excision was proposed, but the patient declined.

Supernumerary renal vessels: analysis of frequency and configuration in 996 computed tomography studies.

BACKGROUND Number, course and division pattern of renal vessels is highly variable. Variant renal vasculature is of high interest in nephrectomy for the renal transplantations, both in deceased and living donors. The purpose of the study was to analyse the frequency of supernumerary renal vessels in a large cohort of patients undergoing the multiphase abdominopelvic computed tomography (CT), as well as analyse the possible patterns of coexisting supernumerary arteries in veins. MATERIALS AND METHODS A retrospective analysis of abdominopelvic CT studies within 1 year period was performed. In each study, number of renal arteries and veins was recorded. Course of left renal vein was classified into normal, retro- or periaortic. For statistical analysis of normal distribution data, t-Student test was used. Chi-square test was used for frequency of variant vessel distribution. Pearson correlation coefficient was used for the analysis of coexistence of supernumerary vessels. RESULTS 996 patients were included in the analysis, male to female ratio: 481:515 (48%:52%). Mean age was 57.9 ± 14.7 years. Single renal arteries were observed in 73% of cases, while single renal veins in 95%. Circumaortic or retroaortic courses of left renal veins were observed in 10% of cases. Number of renal vessels has been compared in patients with and without supernumerary vessels. In patients with supernumerary left renal artery, significantly more right renal vessels were observed. In patients with supernumerary right renal vein, mean number of all remaining vessels was significantly higher. CONCLUSIONS Supernumerary renal vessels are a frequent finding in abdominal CT studies. Finding a supernumerary vessel should increase awareness of possible other supernumerary renal vessels.

Anatomical variations of the coeliac trunk in the homogeneous Polish population

BACKGROUND The abdominal vessels show a number of abnormalities and pathologies knowledge of which is important during open as well as laparoscopic surgeries. One of the most common vessels which pattern has many variations is the coeliac trunk. The present study was undertaken on homogeneous population to assess morphology of the coeliac trunk and to evaluate the possible variability of its branches. MATERIALS AND METHODS Standard abdominal multidetector computed tomography examinations were performed on a total of 1569 patients diagnosed by 2 radiologists independently; in case of doubts common assessment was performed. RESULTS The coeliac trunk followed the classic pattern in 92.7% of the cases (1455/1569 of patients). The gastrosplenic trunk was detected in 4.1% of cases (64/1569); the hepatosplenic trunk in 2.2% of cases (34/1569); the coeliac-mesenteric trunk was observed in 0.5% of cases (8/1569); the hepatogastric trunk in 0.2% of cases (4/1569); the splenomesenteric trunk was detected in 0.1% of cases (2/1569). In the next 0.1% the coeliac trunk was absent. The hepatosplenomesenteric and the coeliac-colic trunk were not observed in the study population. CONCLUSIONS Vascular anatomical abnormality is usually asymptomatic hovewer, its preoperative knowledge is helpful to reduce complications like vascular bleeding when dissecting the hapato-pancreatic region. The coeliac trunk and its branches can be fast and easy evaluated in computed tomography exams performed due to various symptoms from abdominal cavity.