Biomedical subjects

W Harter

Publications and source records attributed to W Harter.

4 recordsLinked to original sources

PubMed2001

Fear-avoidance behavior and anticipation of pain in patients with chronic low back pain: a randomized controlled study.

OBJECTIVE AND DESIGN: In a randomized controlled study, we investigated whether pain anticipation and fear-avoidance beliefs will lead to behavioral avoidance. PATIENTS: Fifty patients with chronic low back pain (CLBP) performed a simple leg-flexion task. Before the test, members of a control group were informed that the movement would not result in any increase of pain, whereas experimental group participants were told that a slight increase of pain could occur. OUTCOME MEASURES: All patients completed the Fear-Avoidance-Beliefs Questionnaire (FABQ) and the Pain Disability Index (PDI). As dependent variables, different behavioral performance parameters were registered by a computerized protocol: number of flexion movements, mean range of motion, and mean work ratio. Furthermore, patients were asked about their pain intensity as well as their fear (at the moment) and finally were asked to judge the unpleasantness of the experiment (using visual analogue scales for each of the three variables). RESULTS: Inducing pain anticipation (by instruction) led to significantly lower levels of behavioral performance as well as increased pain intensity and fear during the test. Behavioral performance was significantly correlated with fear-avoidance beliefs. CONCLUSIONS: Results confirm that pain anticipation and fear-avoidance beliefs significantly influence the behavior of patients with low back pain in that they motivate avoidance behavior. Therapists must be aware of the powerful effects of cognitive processes, which can give rise to fear of pain and, consequently, avoidance behavior.

Clinical Trial↗

PubMed1988

An external beam treatment technique for retinoblastoma.

The main difficulty in the irradiation of retinoblastoma has been to deliver a high uniform dose to the entire retinal surface and spare the lens. Conventional techniques are inadequate to deliver an acceptable dose distribution especially for cases when there are both anterior and posterior lesions. We have developed a procedure to deliver a high dose anteriorly at the ora serrata for a compromise of about 30-35% of the target dose to the lens. The technique consists of 3 pairs of non-coplanar arcs using a 4 MV accelerator. This technique may offer a higher probability of tumor control and cure when gross tumor is present at the ora serrata when compared to the conventional techniques using lateral techniques.

Eye Neoplasms↗

PubMed1978

Hemodynamic assessment of the new aortic Carpentier-Edwards bioprosthesis.

Although glutaraldehyde-preserved porcine aortic Hancock heterografts have lower thromboembolism incidence than mechanical aortic valves, Hancock xenografts provide less functional aortic outflow orifices and thereby greater transvalvular gradients than mechanical prostheses. The newly developed aortic Carpentier-Edwards porcine heterografts comprise a thin-walled Elgiloy flexible metal stent covered with Teflon which provides somewhat wider internal orifices than aortic Hancock valves of the same external annulus diameter. Since aortic Carpentier-Edwards xenografts have not been clinically evaluated previously, the present study assessed cardiac function and heterograft performance (1.7 months postoperation) and clinical status (4.2 months postoperation) of 19 patients with severe aortic stenosis and/or regurgitation prior to surgery. Left ventricular end-diastolic pressures decreased (17 to 9 mm Hg), cardiac index remained normal, and clinical symptomatology diminished markedly. Mean peak transxenograft systolic pressure was only 16 mm Hg (valve area 1.73 cm2), without meaningful regurgitation. Thus aortic Carpentier-Edwards bioprostheses provide generally excellent heterograft function which appears more favorable than previous reports of Hancock xenografts.

Adolescent↗

PubMedDate not supplied

On-line computer analysis of hemodynamic data.

As we come more and more to depend on computers, we need assurance of their reliability and accuracy. Toward this end, a comparison of computer and manual analyses of hemodynamic data was undertaken. The results, reported here, support computer reliability.

California↗