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P Hendrickx

Publications and source records attributed to P Hendrickx.

At least 37 records · Page 2Linked to original sources
PubMed1990

[Experimental meniscus sonography: the influence of imaging geometry on the visualization of meniscal lesions].

Specific meniscal tears were set on prepared cadaver knees to examine the influence of projection factors on the visualisation of these lesions via ultrasound. 7.5 MHz sector- and linear scanner were used. It showed that both the extent of the lesion and also the angle between outgoing echo-direction and reflection plane determines the sonographic findings of meniscal tears. Adapted horizontal tears and vertical radial tears were often not seen. Concentric vertical lesions showed one or two high echogenic lines, depending on the extent of the defect. So it seems that there are limits for an exact sonographic characterization of meniscal lesions.

Evaluation Studies as Topic↗
PubMed1990

[Phantom studies of the value of color-coded Doppler sonography in arterial occlusive disease of the lower extremities].

A new practically orientated phantom for evaluating Doppler Duplex equipment was developed and used to determine the possibilities and limits of color coded Doppler Sonography (Angiodynography) in the diagnosis of arterial occlusive disease of the lower extremity. The problems that may occur in quantifying flow in these arteries are analyzed. The influence of superimposed slices of various soft-tissues on flow quantification, on the spectral waves and on color coded visualisation of the arteries and the possibility to compensate those changes by the use of sonographic contrast agents are discussed.

Arterial Occlusive Diseases↗
PubMed1990

[Postoperative diagnosis following separate replacement of an aortic valve and an ascending aorta using IV-DSA and CT].

We performed a follow-up examination by intravenous DSA and dynamic CT of 14 patients with separate replacement of aortic valve and ascending aorta due to an aneurysm or an aortic dissection. In 5 patients, we found an aortic ectasia at the aortic bulb or a perfused "graft inclusion". Both are best demonstrated with dynamic CT. As a result of the study, the operation technique was changed. In the postoperative management of patients with separate replacement of aortic bulb and ascending aorta, careful monitoring by dynamic CT is necessary even in the absence of clinical symptoms.

Adult↗
PubMed1990

[Results of percutaneous transluminal irradiation of biliary tract carcinoma with 192Iridium].

In 22 patients with bile duct carcinoma's intratumoral irradiation was performed through a percutaneous biliary drainage. 17 of them had been found to be inoperable at laparotomy, 5 others had recurrent carcinoma at the site of a biliodigestive anastomosis. The applied dose ranged from 60 to 80 Gy at 6 mm distance of the centre of the Iridium source. In 12/22 patients a clear reduction in the degree of tumor stenosis could be established. Regarding the survival of the patients (8.6 months) results were relatively poor, due to extensive metastases. Patients with a documented dilatation of tumor stenosis showed a low significant longer survival period (12.3 months) than those without detectable response (4.2 months).

Biliary Tract Neoplasms↗
PubMed1989

[Computed tomographic detection of chemotherapy-induced thymus changes in patients with metastatic testicular tumors].

Serial thoracic CT scans of 100 patients suffering from testicular cancer revealed that the thymus appears to atrophy temporarily during administration of cytostatic agents. About two months after cessation of chemotherapy rebound enlargement of the thymus occurs and persists for about two years followed by a slow involution. Using a semiquantitative score system, thymic CT images of these patients were compared with that of 100 patients suffering from other malignancies, 100 patients without malignant disease and 52 patients with myasthenia gravis, taking into account the age-related changes of the size of the organ. Rebound thymic enlargement should not be misinterpreted as metastatic lymph nodes.

Adolescent↗
PubMed1989

Intravenous DSA and dynamic computed tomography for postoperative follow-up of type A aortic dissections.

We undertook a direct comparison of intravenous digital subtraction angiography and dynamic computed tomography in a follow-up study on 37 patients who had undergone surgery on the thoracic aorta for acute or chronic type A dissections. These are minimally invasive and complementary procedures: IV-DSA provides a clear angiographic image of the dissection, with visualization of the true and false channels, their distal extension and the supra-aortic and abdominal vessels they supply. Dynamic CT best demonstrates the proximal extension of the disease; it visualizes clotting in the false lumen and permits a more accurate measurement of the aortic width, and thus early recognition of a developing aneurysm.

Adult↗
PubMed1988

[Effect of observation time on the perception of details in x-ray pictures].

The authors studied the influence of perception time on the quantified image quality of radiographs, using as an experimental basis the target presentation time during which there was no active involvement of the observer. No change in the influence on the observer was seen down to an observation time of 1 sec.; there was a slight but practically negligible drop on further reduction to 0.5 sec. At 0.1 sec. there was a drop that would have been approximately compensated by a contrast enhancement of object detail to about twice the original value. The influence of the perception time was placed in relation to an example of the influence of structured noise on the detection performance. This influence proved to be significantly greater than that of time. A comparison of the concept of "conspicuity" as defined by Revesz and Kundel was set in relation to the term "Auffälligkeit" ("distinctiveness") coined by Stender. It was established that the quality reserve QR after Borcke corresponds to "Auffälligkeit" as defined by Stender and should best be separated from image quality changes dues to the influence of structured noise on the detection of radiological abnormalities.

Humans↗
PubMed1988

[The place of radiologic research procedures in the diagnosis of aortic dissection].

Aortic dissection is a rare but life-threatening disease that requires a prompt and exact diagnosis. That is why the radiologist now assumes a central role due to the introduction of new imaging modalities. Each of them can make a contribution while having its own limitations. The choice of the right examination procedure and its correct application determine a successful radiological diagnosis. On the basis of experience with more than 150 operated patients we explain our diagnostic strategy in aortic dissection.

Aortic Dissection↗
PubMed1987

Acute type-A dissection of the aorta: which diagnostic modes remain for surgical indication?

The natural course of acute type-A dissection of the aorta (AADA) implies a mortality of 50% within the initial 2 days. Preoperative diagnostic tests have to be expeditious while avoiding hypertension and direct manipulation of the aneurysm to prevent aortic rupture. Since 1979, 51 patients have been operated upon for AADA. The diagnosis was established by one or more of the following methods: transthoracic echocardiography (TTE); transesophageal echocardiography (TEE); conventional angiography (CA); intravenous digital subtraction angiography (DSA); and computed tomography with bolus injection of contrast medium (CT). TTE (n = 26) showed a dissection in 72%, suggested an intimal flap in 25%, and missed the diagnosis in 1 case. CT (n = 15) and DSA (n = 10) failed to indicate dissection in 1 case each. CA (n = 27) demonstrated dissection in every case but was the most time-consuming and stressful method. Since the introduction of combined transthoracic and transesophageal echocardiography, no other diagnostic methods have been used. On the basis of this experience, we propose the following diagnostic plan: 1. in AADA, the demonstration of an intimal flap in the ascending aorta by TTE/TEE is an indication for immediate surgery without further diagnostic measures (10 patients: no false-positive findings); 2. if a dissection is suggested by TTE/TEE, then DSA is performed if the supra-aortic branches are suspected to be compromised; CT is preferred if an extrapericardial aortic rupture is suspected; 3. the time-consuming and stressful diagnostic approach of conventional angiography is no longer indicated.

Acute Disease↗
PubMed1986

[Suitability and comparison of compensating filters for thoracic diagnosis].

The effect of three types of filter on the quality of radiographs of the chest was compared. These filters improve visualization of mediastinal structures without significantly reducing the quality of the pulmonary image. In practice the Du Pont filter proved best; the quality of the central and peripheral portions of the lung image is equal to that of an ordinary radiograph and visualization of the mediastinum is improved. The Agfa-Gevaert filter showed no significant disadvantages compared with the ordinary techniques but the improvement in mediastinal visualization is not that marked. The 3 M filter yields poor images of the central portions of the lung and its type of construction prevents the retrocardiac structures from being pictured as well as with the other filters.

Humans↗
PubMed1986

[I.v. DSA in the diagnosis and follow-up of thoracic aortic dissection].

Intravenous DSA was performed in 53 patients with suspected dissection of the thoracic aorta and in 13 patients following surgery for aortic dissection. In 36 patients, the suspected diagnosis could be excluded definitely and, in 14 cases out of 17, a dissection was correctly diagnosed. All 11 type B dissections were correctly diagnosed. Of six type A dissections, only three were adequately demonstrated by IV DSA. In type B dissections, IV DSA is reliable, but in type A dissection with massive aortic insufficiency or pericardial tamponade the findings are not reliable. In all 13 patients who had surgery for dissection, IV DSA proved suitable for showing the anastomosis and progress of the disease.

Aortic Dissection↗
PubMed1985

[Peripheral venous digital subtraction angiography in the follow-up of aortocoronary venous bypass grafts].

36 patients with 68 aorto-coronary venous bypass grafts (45 of which were angiographically patent) were examined via DSA (DV12V, serial mode, Philips) and angiography. Imaging was triggered via R waves, and effected in RAO 30 degrees, LAO 60 degrees, and AP projection. 63 of the 68 grafts were correctly detected (92.7%). Two anterior interventricular branch grafts (RIVA = ramus interventricularis anterior) were not visualised via DSA (95.6% sensitivity). One graft each to the RIVA, to the right coronary artery (RCA), and to the posterior branch of the lateral cutaneous branches of intercostal arteries (PLA), were falsely found to be patent (87% specificity). Grafts were visualised in full length. In some cases morphological changes of the walls were also visible.

Coronary Angiography↗