PubMed Health⌕ Search

Biomedical subjects

S Sunderland

Publications and source records attributed to S Sunderland.

At least 19 recordsLinked to original sources
PubMed1996

The hydroxyapatite orbital implant: a prospective study.

The hydroxyapatite orbital implant was first released for use as an orbital implant in humans in August 1989. It has been shown to be well tolerated, providing good motility of the artificial eye with a low complication rate when used as a primary implant. This prospective study evaluated the hydroxyapatite orbital implant used as both a primary and a secondary implant. Sixty patients were implanted between October 1992 and November 1994, 28 being implanted as a primary procedure at the time of enucleation or evisceration, and 32 as a secondary procedure. Seven patients underwent second-stage drilling and pegging of the implant. The mean follow-up time was 13 months (range 2-26 months). A standardised operative and post-operative protocol was followed. The patients were evaluated post-operatively for the amount of enophthalmos, degree of upper lid sulcus deformity, motility of the prosthesis, location of the implant in the socket, socket status and the presence or absence of discharge, position of the drill hole and coverage of the implant. Complications and their management were documented. Both patient and surgeon made a subjective assessment of cosmesis and the patient's satisfaction with the overall result was noted. The results of this study show the hydroxyapatite orbital implant to provide excellent motility of the artificial eye and good cosmesis with a low rate of complications when used both as a primary and as a secondary implant.

Adolescent↗
PubMed1995

Use of Proplast II as a subperiosteal implant for the correction of anophthalmic enophthalmos.

BACKGROUND: A variety of autogenous and alloplastic materials have been used as subperiosteal implants to correct anophthalmic enophthalmos. Proplast II is a synthetic porous composite of Teflon polymer and alumina. Proplast II offers a number of advantages over other commonly used alloplastic materials such as silicone and polymethyl methacrylate. It is light, porous, resilient, malleable, and easy to shape. It can be readily sterilised after shaping. It has been found to integrate with the surrounding tissues, thereby minimising the risk of subsequent implant migration and extrusion. METHODS: Proplast II was used as a subperiosteal implant in a total of 15 anophthalmic patients during the period June 1990 to March 1994. The indication for this procedure in all patients was poor orbital volume replacement despite the prior insertion of an adequately sized spherical socket implant. RESULTS: The results were excellent with a good correction of preoperative upper eyelid sulcus deformity. There were no operative complications nor any serious postoperative complications. The implants were well tolerated. CONCLUSION: Proplast II can be highly recommended for use as a subperiosteal implant.

Adult↗
PubMed1994

The 'baseball' orbital implant: a prospective study.

The 'baseball' orbital implant was described by Frueh and Felker in 1976. Although this implant was originally described for use as a secondary implant, it has also been widely used as a primary implant at the time of enucleation. This prospective study evaluated the effectiveness of this implant used both primarily and secondarily. Forty-four patients were implanted between April 1990 and May 1991, 19 of the implants being primary and 25 secondary. A standardised operative and post-operative protocol was followed. The mean follow-up time was 31 months (range 24-36 months). The patients were evaluated for the degree of volume replacement, implant and associated prosthesis motility, secondary eyelid and socket problems, patient satisfaction, the need for further surgery and post-operative complications. The overall results achieved by primary implantation were superior to those of secondary implantation. Our results suggest that this implant provides a satisfactory functional and cosmetic rehabilitation of the anophthalmic patient with few complications.

Adolescent↗
PubMed1993

A comparison of temperature rise in human calf muscles following applications of underwater and topical gel ultrasound.

For ultrasound to be effective, a conducting medium must be placed between the soundhead and the skin. Little research has been performed to test whether or not these mediums actually work. The purpose of this study was to compare the effect of tap water immersion and ultrasound gel conducting mediums on tissue temperature rise in the human leg. A 23-gauge hypodermic needle microprobe was inserted 3 cm deep into the medial portion of the gastrocnemius muscle of 20 subjects. Each subject participated in two random order treatments using tap water immersion and topical gel conducting mediums. Each treatment consisted of continuous ultrasound delivered topically at 1.5 W/cm2 for 10 minutes. During both treatments, the soundhead was moved at a speed of 4 cm per second, and the temperature was recorded every 30 seconds. A significant difference was found between the two treatment methods [t(19) = 9.18, p < .001]. The topical gel increased tissue temperature 4.8 degrees C, whereas the underwater treatment increased tissue temperature only 2.1 degrees C. Therefore, at a tissue depth of 3 cm, ultrasound gel is a better conducting medium than water. Also, the authors discovered that it took nearly 8 minutes for the temperature to reach therapeutic levels during the gel technique. These findings should be of clinical significance to clinicians who regularly use ultrasound.

Adult↗
PubMed1990

The anatomy and physiology of nerve injury.

Nerves have a structure of considerable complexity with features of special relevance to nerve injury and nerve regeneration. These include variations in the cross-sectional areas devoted to fascicular and epineurial tissue, the fascicular redistribution and mixing of different branch fibers brought about by fascicular plexuses, and the numbers of nerve fibers representing individual branches. The elasticity and tensile strength of nerve trunks and their capacity to resist traction deformation reside in the fascicular tissue, while the epineurium provides a protective cushion against compression. The microstructure of nerve trunks provides the basis for a classification of nerve injuries into five degrees of severity with partial and mixed types--each with a clearly defined pathology and distinguishing clinical features. Following a transection injury, changes occur in the severed axons, endoneurial tubes, fasciculi, and nerve trunk. The type of injury and the nature of these changes determine the outcome of axon regeneration.

Axons↗
PubMed1984

Repair of the brachial plexus directed to restoring elbow flexion.

Attention is directed to certain variations in the composition and structural features of the brachial plexus which provide several alternative routes for motor nerve fibers and regenerating axons to reach the elbow flexor muscles. The possibility that such aberrant pathways can exist should be taken into consideration when assessing the effectiveness and value of controversial methods of plexus repair for the restoration of elbow flexion.

Brachial Plexus↗
PubMed1976

Pain mechanisma in causalgia.

A study of the clinical features of causalgia and the central neuronal effects of injuries to peripheral nerves suggests that causalgia is the functional expression of the intensity of the retrograde neuronal reaction in which pools of dorsal horn neurones become converted into foci of abnormal activity. These foci initiate a chain reaction along transmission pathways as far centrally as the cortex, causalgia being the terminal effect of this disorderly activity on the sensorium. This is the basis of the 'turbulance hypothesis' introduced to account for the pain.

Causalgia↗
PubMed1976

The nerve lesion in the carpal tunnel syndrome.

The relative roles of pressure deformation and ischaemia in the production of compression nerve lesions remain a controversial issue. This paper concerns the genesis of the structural changes which follow compression of the median nerve in the carpal tunnel. The initial lesion is an intrafunicular anoxia caused by obstruction to the venous return from the funiculi as the result of increased pressure in the tunnel. This leads to intrafunicular oedema and an increase in intrafunicular pressure which imperil and finally destroy nerve fibres by impairing their blood supply and by compression. The final outcome is the fibrous tissue replacement of the contents of the funiculi.

Arm↗