PubMed Health⌕ Search

Biomedical subjects

W J Link

Publications and source records attributed to W J Link.

13 recordsLinked to original sources
PubMed1982

The plasma scalpel: a new thermal knife.

A new thermal knife, the plasma scalpel, capable of simultaneous division of tissue and coagulation of blood vessels, is described. A high temperature argon gas plasma (unrelated to blood plasma) is created by passing the gas through a direct current arc, ionizing the gas and elevating its temperature to 3000 degrees C. A small plasma cutting jet is formed by a nozzle at the tip of the handpiece. Liver resections and muscle transections performed in a canine model, and full thickness burn excisions in a pig skin model showed effective division of tissue and significantly less blood loss when compared to the steel scalpel. Wound healing studies of histologic comparisons and wound breaking strength were performed for steel, plasma, laser, and electrosurgical scalped incisions in the skin of mice and rats. All thermal knife wounds showed localized tissue damage at the edges of the incision, but the events of healing began at the same time. Compared to the steel scalpel, there was a three to six day delay in the onset of healing, but healing occurred in the normal fashion and all thermal knife wounds reached the same healed breaking strength as the steel scalpel wounds. Clinically, the plasma scalped has been used for 138 procedures in 96 patients. The majority of cases have been transection of muscle, hepatic resection or debridement, or soft tissue debridement. Muscle transection data for the plasma scalped compared to the electrosurgical scalpel has shown virtually no blood loss with a shorter time to hemostasis for the plasma scalpel. The plasma scalpel has proved to be an effective thermal knife, capable of simultaneous division and coagulation. Further development work and proof of its efficacy in the clinical setting are necessary to establish the plasma scalpel and adequately demonstrate its proper role in surgery.

Animals↗
PubMed1979

Surface modification of intraocular lenses to reduce corneal endothelial damage.

Two methods of surface modification of PMMA, permanent and temporary, were investigated for use on intraocular lenses to reduce corneal endothelial damage due to corneal-IOL touch. Monomer grafting using gamma irradiation was found to produce permanently hydrophilic surfaces. Temporary surface modifications developed and tested were peelable and dissolvable coatings. Test samples were touched to freshly excised rabbit corneas to evaluate the effectiveness of the various surface modifications in reducing endothelial cell damage. This touch testing was performed using static testing in which the test sample was touched to the cornea without movement and dynamic testing in which there was relative movement between the cornea and the test sample. While unmodified PMMA did significant cell damage in both static and dynamic tests perpamently modified (hydrophilic grafted) surfaces were found to perform well in the static, but not in the dynamic tests. Dissolvable coatings performed well in both tests, even with very thin coatings. There was little differentiation between the various water-soluble coatings tested. Due to its characteristics and rate of dissolution, polyvinyl alcohol appears to be an optimum material for coating IOLs. A series of in vitro and in vivo tests performed to assess its safety indicate that PVA is nontoxic and safe in animal eyes.

Animals↗
PubMed1976

A plasma scalpel: comparison of tissue damage and wound healing with electrosurgical and steel scalpels.

We have been evaluating a plasma scalpel (the term has no relation to blood plasma) for four years that, with the generation of a small, hot gas jet (3,000 C), can cut tissue and simultaneously cauterize blood vessels of 3 mm in diameter. Twenty-nine plasma scalpel hepatectomies in dogs and comparative skin wound healing (with steel and electrosurgical scalpels) in 90 mice showed that bleeding was reduced, and the thermal insult in liver tissue was limited to 2 mm from the incision; both liver and mouse skin incisions healed without complication. The completion of epithelization of mouse skin wounds occurred at 2 to 6, 6 to 14, and 6 to 18 days, and the average scar width was 0.8, 1.4, and 2.1 mm for the steel, electrosurgical, and plasma scalpels, respectively. The plasma scalpel effectively cauterizes blood vessels as it cuts, leaving limited damaged tissue. We have recently begun human trials, and the device shows promise as a clinical tool.

Animals↗
PubMed1976

The plasma scalpel.

The plasma scalpel simultaneously cuts tissue and cauterizes blood vessels measuring 3 mm in diameter with a small, hot (3000 C) gas jet. In animal studies, the amount of hemorrhage has been shown to be less with the plasma scalpel than with steel or electrosurgical scalpels, and incisions have healed without complications. Amount of damaged tissue is limited. Human trials are under way, and the device shows promise as a clinical tool.

Absorption↗
PubMed1975

Ultrasound evaluation of microanastomosis.

The Doppler ultrasound flowmeter with a pencil probe, emitting at a frequency of 10 megacycles/second, was used to making recordings along intact and repaired digital arteries and veins. In normal digital arteries, the flow averaged 3.78 ml/min. The ability of the method to appraise the condition of an anastamosis was evaluated in five patients with partial or complete digit, hand, or arm replants, and found quite satisfactory. Beginnings were made in developing criteria for satisfactory flow in these small arteries.

Adolescent↗
PubMed1975

Plasma scalpel excision of burns. An experimental study.

We used a plasma scalpel to excise experimental full-thickness burns in 12 pigs, followed by immediate skin autografting. The results were as follows: (1) The skin autograft takes were excellent following the plasma scalpel excisions, and they healed on essentially the same time scale as similar autografts following steel scalpel excisions, producing scars of similar sizes. (2) Pigs in which burn wounds were excised with a steel scalpel lost an average of approximately 5 gm of blood for every one gm lost in the animals which had excisions with the plasma scalpel. (3) The time required for a plasma scalpel burn excision was essentially the same as that required for a standard steel scalpel.

Animals↗
PubMedDate not supplied

The influence of suction catheter tip design on tracheobronchial trauma and fluid aspiration efficiency.

The suctioning efficiency and trauma-producing characteristics of five commercially available tracheobronchial suction catheters (Pharmaseal Tri-Flo, NCC Gentle-Flo, Argyle Aero-Flo, Argyle Dual Side-Hole, and Pharmaseal Whistle-Tip) were experimentally evaluated in anesthetized healthy dogs. The tendency of catheters to invaginate or "grab" tracheobronchial mucosa was observed with a bronchofiberscope during suctioning. Mucosal grabbing was seldom seen even at high (greater than 300 torr) vacuum levels with the cateter tip in the trachea. All catheters were observed to invaginate mucosa in lobar and segmental bronchi, with the frequency of grabbing being a function of airway anatomy, airway size, catheter orientation, tip design, and vacuum level. Catheters with multiple side-holes appeared to invaginate mucosa less frequently than the single side-hole catheter. Repeated suctioning of anesthetized healthy dogs followed by tracheobronchial excision, gross observation, and histologic examination of mucosal tissue biopsies demonstrated significant differences in the frequency and severity of lesions caused by the tracheobronchial suction procedure. All catheters were observed to damage airway lining, the damage related to multiple side-hole catheters appearing to be associated entirely with the act of cateter insertion and not with the application of vacuum. Only the Whistle-Tip design produced measurable damage beyond that related to catheter insertion. The average tip-suctioning effectiveness for each catheter, determined in vitro by aspirating a thin, uniform layer of simulated mucus, was found to be significantly higher for the Tri-Flo and Whistle-Tip catheters than the others, the Aero-Flo being least effective. Preliminary attempts to demonstrate this difference in suctioning effectiveness by comparing the performance of the catheters which displayed the highest and lowest tip suction effectiveness in a standardized clinical suctioning procedure revealed no significant difference in the percentage of mucus removed by either catheter. Additional studies should clarify this apparent contradiction.

Animals↗