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Biomedical subjects

B M O'Brien

Publications and source records attributed to B M O'Brien.

At least 109 records · Page 6Linked to original sources
PubMed1983

Comparison of vascular hemodynamics in experimental models of microvascular anastomoses.

Blood flow was measured in the canine saphenous artery using electromagnetic flowmetry. Significant increase in blood flow was noted after occlusion of the distal femoral artery. However, after raising a saphenous island flap there was no significant change in the blood flow before and after distal femoral artery occlusion. The flap peripheral resistance and blood flow were compared after end-to-end and end-to-side anastomosis and no statistical difference was noted.

Animals↗
PubMed1983

The instep of the foot as a fasciocutaneous island and as a free flap for heel defects.

The instep flap needs neither muscle nor a transposition base for survival or innervation. It can be transposed as an island fasciocutaneous flap either on the medial or lateral plantar neurovascular bundles or both, and it can be transferred also as a free flap from the opposite foot. Four cases demonstrating the use of the flap as an island and free flap are presented with follow-up ranging from 1 to 2 years. The absence of muscle in the flap provides greater stability of the heel reconstruction and results in a lesser secondary defect. Sensation in the flaps is diminished but adequate for long-term function, but hyperkeratotic reaction remains an unpredictable problem. The ability to transfer the flap as a free transfer widens the scope of the flap to reconstruct both heel and forefoot defects where local instep tissue or vascularity are inadequate for local reconstruction. The secondary defect, particularly when no muscle is included in the flap, has been minimal.

Adolescent↗
PubMed1982

The computer programmed multi-image lecture.

Computer programmed multi-image presentations enhance considerably the visual content of an audiovisual presentation. A multi-image production provides ample opportunity to present the pre- and post-operative images simultaneously, enabling the audience to compare and comprehend the results with ease. With more than one image the natural sequence of dissection details can be shown, resulting in continuity of thought. The dissolve mechanism offsets any visual fatigue of the audience. The films contribute animation sequences which cannot be demonstrated well on slides. A presentation of all material provides the lecturer with maximum control with the minimum of effort, utilising one button. A computer programmed multi-image production is a complex medium of audiovisual presentation and needs a great deal of time and experience and is not to be lightly undertaken. With the increased number of slides, images and projectors the margin for error is small. Careful slide assembly and repeated rehearsals are the keys to success. At the moment, its use is recommended for special lectures only with adequate consideration being given for the increased expense of production.

Audiovisual Aids↗
PubMed1981

Effect of lymphangiography on lymphedema.

Lymphangiography, using oily radiopaque Lipiodol Ultra Fluid has been shown to increase lymphedema in one-third of the patients with obstructive lymphedema and to cause lymphatic obliteration (demonstrated histologically). No effective element has been observed, although subclinical infection could not be ruled out. Allergy is another possible contributor, but the evidence from this series suggests that Lipiodol may act as a direct irritant when it is not rapidly cleared, as in the case of obstructive lymphedema, and proceed to obliteration of the residual lymphatics. On the basis of these findings, elective routine preoperative lymphangiography for lymphedema is considered strongly inadvisable.

Female↗
PubMed1980

Results of the use of autotransplantation of the intraabdominal testis using microsurgical vascular anastomosis.

This study indicates that where facilities are available, the use of autotransplantation of the intraabdominal testis with microsurgical anastomosis to vessels of the groin is an acceptable, and possibly the best, alternative to orchidectomy for the intraabdominal testis. It is certainly justifiable in the case of the bilateral intraabdominal testis but in the case of the unilateral intraabdominal testis with a normally descended and apparently normal testis in the opposite hemiscrotum, the incresed incidence of neoplasia in intraabdominal testes should be taken into account in the decision on the method of treatment.

Adolescent↗
PubMed1979

Patency rates in end to side anastomoses in the rabbit.

It is suggested that more widespread use of the end to side microvascular suturing technique should be made, especially in arteries. A simple experimental practice model in the rabbit is suggested. Patency rates comparable to end to end anastomosis can be achieved.

Animals↗
PubMed1979

The effects of suturing technique and vessel size on patency after microarterial repair.

According to most of the literature, sutures for microarterial repair must include the intima to prevent an "intimal flap" and occlusion of the anastomosis. Some authors have said that vessel diameter affects patency rate. This study was designed to evaluate these two statements. The femoral arteries (about 1.0 mm in diameter), the epigastric arteries (about 0.5 mm), and the central ear arteries (about 0.5 mm) of rabbits were studied. Alternate arteries were repaired using conventional suturing techniques or sutures which included the adventitia and media but excluded the intima. The patency rate in the 1 mm or 0.5 mm vessels was not affected by inclusion or exclusion of the intima from the microarterial repair. The patency rate for conventionally repaired arteries 1 mm in diameter was significantly higher than that for 0.5 mm arteries.

Abdominal Muscles↗
PubMed1979

Lymphaticolymphatic anastomosis.

Lymphaticovenous anastomosis has proved valuable in the treatment of obstructive lymphedema. Histological studies of this anastomosis have shown the lymphatic component to be almost inactive in anastomotic healing. In order to clarify the role of the lymphatics, experimental lymphaticolymphatic anastomoses were performed in canine femoral lymphatics. The technique developed calls for eight to ten 19 mu sutures to prevent vessel wall collapse, and preservation of the vasa vasorum. Vessels were harvested from one hour to six weeks after anastomosis. Scanning electron microscopy and conventional light histology revealed the lymphatics to have active healing of the intima with complete reendothelialization by two weeks. The techniques developed in this study are directly applicable to human lymphaticovenous anastomosis.

Animals↗