PubMed Health⌕ Search

Biomedical subjects

B Ghaye

Publications and source records attributed to B Ghaye.

At least 19 recordsLinked to original sources
PubMed2001

Evaluation of CT time-density curves of lower-limb veins.

UNLABELLED: Szapiro D, Ghaye B, Willems V, et al. Evaluation of CT time-density curves of lower-limb veins. Invest Radiol 2001;36:164-169. RATIONALE AND OBJECTIVES: To evaluate time-density curves of the lower-limb veins for optimization of CT venography. METHODS: Fifty patients referred for chest CT were randomized into five equal groups. Five anatomic levels (abdomen, pelvis, proximal thigh, knee, and midcalf) were evaluated by a dynamic acquisition during 7 minutes. Computed tomography attenuation values of the veins, arteries, and adjacent muscles were measured for each level and plotted into curves versus time. Venous enhancement was also assessed qualitatively. RESULTS: Mean peak enhancement values of the inferior vena cava and the iliac, femoral, popliteal, anterior tibial, posterior tibial, and peroneal veins were, respectively, 112 +/- 16, 103 +/- 17, 93 +/- 23, 98 +/- 30, 112 +/- 28, 137 +/- 28, and 124 +/- 29 Hounsfield units. These were reached at 93 +/- 9.5, 129 +/- 15, 135 +/- 20, 147 +/- 57, 124 +/- 32, 123 +/- 17, and 123 +/- 18 seconds. Homogeneous opacification was obtained after 210 seconds. An optimal time window for CT venography was obtained between 210 and 240 seconds for the calf level and between 180 and 300 seconds for above-knee veins. CONCLUSIONS: For sequential CT venography, a caudocranial acquisition of the lower-limb veins, starting at 210 seconds, should allow optimal clot detection.

Adult↗
PubMed2001

Peripheral pulmonary arteries: how far in the lung does multi-detector row spiral CT allow analysis?

PURPOSE: To analyze the influence of multi-detector row spiral computed tomography (CT) on identification of peripheral pulmonary arteries. MATERIALS AND METHODS: Peripheral pulmonary arteries were analyzed on optimally opacified contrast material-enhanced spiral CT angiograms in 30 patients devoid of pleuroparenchymal disease who underwent scanning with multi-detector row CT (collimation, 4 x 1 mm; pitch, 1.7-2.0; scanning time, 0.5 second). Two series of scans were systematically generated from each data set, 1.25-mm-thick (group 1) and 3-mm-thick (group 2) sections, leading to the analysis of 600 segmental (20 arteries per patient), 1,200 subsegmental (40 arteries per patient), 2,400 fifth-order (80 arteries per patient), and 4,800 sixth-order (160 arteries per patient) pulmonary arteries in each group. RESULTS: Multi-detector row CT with reconstructed scans of 1.25-mm-thick sections (group 1) allowed (a) analysis of a significantly higher percentage of subsegmental arteries (94% in group 1 vs 82% in group 2; P <.001) and (b) a significantly higher percentage of fifth- and sixth-order arteries, respectively, identified in 74% and 35% of cases in group 1 and 47% and 16% in group 2 (P <.001). The causes for inadequate depiction of subsegmental branches in group 1 were partial volume effect (43%), anatomic variants (39%), and cardiac (17%) and respiratory (1%) motion artifacts. CONCLUSION: Multi-detector row CT with reconstructed scans of 1.25-mm-thick sections enables accurate analysis of peripheral pulmonary arteries down to the fifth order on spiral CT angiograms.

Angiography↗
PubMed2001

Imaging guided thoracic interventions.

Interventional Radiology is a technique based medical specialty, using all available imaging modalities (fluoroscopy, ultrasound, computed tomography, magnetic resonance, angiography) for guidance of interventional techniques for diagnostic or therapeutic purposes. Actual, percutaneous transthoracic needle biopsy includes core needle biopsy besides fine needle aspiration. Any pleural, pulmonary or mediastinal fluid or gas collection is amenable to percutaneous pulmonary catheter drainage. Treatment of haemoptysis of the bronchial artery or pulmonary artery origin, transcatheter embolization of pulmonary arteriovenous malformations and pseudoaneurysms, angioplasty and stenting of the superior vena caval system and percutaneous foreign body retrieval are well established routine procedures, precluding unnecessary surgery. These techniques are safe and effective in experienced hands. Computed tomography is helpful in pre- and postoperative imaging of patients being considered for endobronchial stenting. Many procedures can be performed on an outpatient basis, thus increasing the cost-effectiveness of radiologically guided interventions in the thorax.

Biopsy, Needle↗
PubMed2000

[How I investigate ... thoracic artery dissection].

Thoracic aortic dissection constitutes an acute pathology that requires a rapid, accurate and reliable diagnosis. The authors describe and illustrate the advantages and limitations of imaging modalities used in this pathology.

Aortic Dissection↗
PubMed2000

Combined CT venography of the lower limbs and spiral CT angiography of pulmonary arteries in acute pulmonary embolism: preliminary results of a prospective study.

PURPOSE: To determine the clinical accuracy of combined CT venography (CTV) and spiral CT angiography (SCTA) in patients suspicious of acute pulmonary thrombo-embolism. MATERIALS AND METHODS: 278 consecutive patients referred for SCTA for suspicion of acute pulmonary embolism (APE) underwent subsequent evaluation of the veins of the lower limbs and abdomen (CTV) within one examination without additional injection of contrast medium. Sixty-nine patients had no further study. Two hundred and nine patients were included in the study, 199 had US and 51 phlebography (PG) within 48 hours from SCTA-CTV. The investigators were blinded to the results of CT. When results of CTV and US were discordant, phlebography was indicated. RESULTS: SCTA was positive in 89 patients, negative in 119 and indeterminate in 1. CTV was positive in 99 patients, negative in 103 and indeterminate in 7. US was positive in 87 patients, negative in 97 and indeterminate in 15. PG was positive in 21 patients, negative in 29 and indeterminate in 1. Excellent correlation was found between CTV and US (k = 0.84) and moderate correlation between CTV and PG, and US and PG (k = 0.53). CONCLUSIONS: Combined SCTA and CTV is a rapid and accurate one-session examination in patients suspicious of acute pulmonary thrombo-embolism.

Acute Disease↗
PubMed1999

Accessory cardiac bronchus: 3D CT demonstration in nine cases.

Accessory cardiac bronchus (ACB) has been described mainly as isolated case reports in the literature. We report nine consecutive cases of ACB, which occurred in five males and four females and were detected in 11,159 routine spiral CT examinations of the chest, performed between 1994 and 1998. Frequency of the anomaly was 0.08 %. Accessory cardiac bronchus originated from the intermediate bronchus in eight cases and from the right main bronchus in one case. Mean largest diameter of ACB was 8.7 mm (range 4.0-13.8 mm) and mean length was 11.9 mm (range 4.2-23.4 mm). An abnormal pulmonary artery was observed in one case. Six bronchi presented with a blind distal extremity and three showed a ventilated lobulus with a mean largest diameter of 37.5 mm (range 18.6-62.0 mm). All ACBs were documented by 3D shaded-surface display (SSD) and virtual endobronchial navigation, which may facilitate the diagnosis. The literature was reviewed.

Adult↗
PubMed1999

Percutaneous CT-guided lung biopsy: sequential versus spiral scanning. A randomized prospective study.

The aim of this study was to evaluate in a prospective and randomized study spiral versus sequential scanning in the guidance of percutaneous lung biopsy. Fifty thoracic lesions occurring in 48 patients were biopsied by a senior and a junior operator. Six different time segments of the procedure were measured. Scanning mode versus length of procedure, pathological results, irradiation and complications were evaluated. Total duration of the procedure and of the first sampling was significantly longer with spiral CT for the senior operator (p < 0.004). No significant time difference was observed for the junior operator. Diameter of the lesion, depth of location, position of the patient and needle entry site did not influence the results. The sensitivity was 90.9, specificity 100, positive predictive value 100 and negative predictive value 60 % for spiral CT, and 94.7, 100, 100 and 85.7 % for sequential CT, respectively. Eleven pneumothoraces and ten perinodular hemorrhages were seen with spiral CT and six and ten, respectively, with sequential CT. The mean dose of irradiation was 4027 mAs for spiral CT and 2358 mAs for conventional CT. Spiral CT does neither reduce procedure time nor the rate of complications. Pathological results do not differ compared with sequential CT, and total dose of irradiation is higher with spiral scanning.

Adult↗
PubMed1999

Value of FDG-PET in detecting residual or recurrent nonsmall cell lung cancer.

In order to evaluate the usefulness of 18-fluorodeoxyglucose (FDG) positron emission tomography (PET) in the assessment of therapeutic effects, a study was performed before and after therapy in 126 patients with non-small cell lung cancer (NSCLC) codified stage I to stage IIIB. Treatment with an early curative result was given in 58 patients, whereas in 68 cases it was limited to palliation. During the treatment follow-up period (8-40 months), each patient was evaluated every 3 months by clinical examination and < or =6 months by imaging techniques (PET and computed tomography (CT)). A diagnosis of persistent or recurrent tumour was established by means of pathological analysis in 31 patients and by clinical evolution and subsequent imaging progression in 29 other patients. PET showed increased FDG uptake in all cases (n = 60) of persistent or recurrent tumour, whereas CT was nonspecific in 17 cases. Conversely, there were five false positive cases via PET imaging and three via CT. In detecting residual or recurrent NSCLC, PET had a sensitivity of 100% and specificity of 92%, whereas CT had a sensitivity and specificity of 71% and 95% respectively. In conclusion, 18-fluorodeoxyglucose positron emission tomography correctly identified response to therapy in 96% (121 of 126) of patients. Positron emission tomography appears to be more accurate (p = 0.05) than conventional imaging in distinguishing persistent or recurrent tumour from fibrotic scar in patients undergoing treatment for non-small cell lung cancer.

Adult↗
PubMed1998

Fluorine-18 deoxyglucose positron emission tomography for the detection of bone metastases in patients with non-small cell lung cancer.

Despite advances in morphological imaging, some patients with lung cancer are found to have non resectable disease at surgery or die of recurrence within a year of surgery. At present, metastatic bone involvement is usually assessed using bone scintigraphy, which has a high sensitivity but a poor specificity. We have attempted to evaluate the utility of the fluorine-18 deoxyglucose positron emission tomography (FDG PET) for the detection of bone metastasis. One hundred and ten consecutive patients with histological diagnosis of non-small cell lung cancer (NSCLC) who underwent both FDG PET and bone scintigraphy were selected for this review. In this group, there were 43 patients with metastatic disease (stage IV). Among these, 21 (19% of total group) had one or several bone metastases confirmed by biopsy (n = 8) or radiographic techniques (n = 13). Radionuclide bone scanning correctly identified 54 out of 89 cases without osseous involvement and 19 out of 21 osseous involvements. On the other hand, FDG PET correctly identified the absence of osseous involvement in 87 out of 89 patients and the presence of bone metastasis in 19 out of 21 patients. Thus using PET there were two false-negative and two false-positive cases. PET and bone scanning had, respectively, an accuracy of 96% and 66% in the evaluation of osseous involvement in patients with NSCLC. In conclusion, our data suggest that whole-body FDG PET may be useful in detecting bone metastases in patients with known NSCLC.

Aged↗
PubMed1997

Whole-body 18FDG positron emission tomography in the staging of non-small cell lung cancer.

Despite advances in morphological imaging, some patients with lung cancer are found to have nonresectable disease at surgery or die of recurrence within yr of surgery. We performed a prospective study in 109 patients to compare the accuracy of whole-body positron emission tomography (PET) using fluorine-18 deoxyglucose (18FDG) and conventional imaging (CI) methods for the staging of non-small cell lung cancer (NSCLC). When CI or PET study suggested metastatic disease, confirmation was obtained by biopsy or follow-up information. As compared to CI, 18FDG-PET correctly changed the N stage in 22 patients (33%) and the M stage in 15 patients (14%). For the detection of distant metastases, PET study showed five false-positive sites and no false-negative cases. Currently, the accuracy of PET in the detection of M stage is 96%. Our study shows that visual interpretation of whole-body fluorine-18 deoxyglucose-positron emission tomography images can improve the diagnostic accuracy in the staging of non-small cell lung cancer. Further experience is needed to establish if metabolic imaging would be a cost-effective tool in the future management of lung cancer.

Carcinoma, Non-Small-Cell Lung↗
PubMed1996

Staging of the mediastinum: value of positron emission tomography imaging in non-small cell lung cancer.

Recent studies have shown limitations of morphological imaging in staging mediastinal lymph node involvement in lung cancer. In contrast to computed tomography (CT), which depends primarily on anatomical imaging features, positron emission tomography (PET) with 18-fluorodeoxyglucose (FDG) depends mainly on the metabolic characteristics of a tissue for the diagnosis of disease. We have performed a prospective study comparing FDG-PET and CT of the thorax in the presurgical assessment of the mediastinum in 50 patients with newly diagnosed non-small cell lung cancer (NSCLC). CT and PET scans were interpreted separately, and results were compared to pathological staging obtained during thoracotomy. Hilar or mediastinal lymph node involvement was present in 58%. In staging for lymph node involvement, CT had a sensitivity of 72% and specificity of 81%, whereas PET had a sensitivity and specificity of 90% and 86%, respectively. When the PET study was compared to histological results, there were four cases showing more advanced mediastinal involvement with PET and four cases showing less involvement with PET. From our preliminary results, we conclude that positron emission tomography with 18-fluorodeoxyglucose is significantly more accurate than computed tomography in the mediastinal staging of non-small cell lung cancer.

Aged↗