Minimal Tissue Reaction Research Articles

Studies concerning the usefulness of catgut, PGA and polyester for abdominal fascia closure (author's transl)

The abdominal fascia incisions of 133 rabbits were closed either with plain gut, chromic gut, PGA or polyester threads. The breaking strength of the wounds were determined tensiometrically at different time intervals and the tissue was examined histologically. For a three-week period the strength of the abdominal wall depends significantly on the intactness of the threads. PGA produces minimal inflammatory reactions, but loses its strength after a fortnight. Since longitudinal incisions are endangered by severe muscle pull, this material cannot be recommended because of the possibility of wound disruption and the formation of hernias. The loss of strength of catgut plain and catgut chromic starts later. Catgut causes inflammatory reactions within the wound area leading to loss of strength of the sutured tissue. Thus incisions of the abdominal fascia should not be closed with catgut. The non-resorbable suture material polyester shows satisfactory strength and minimal tissue reaction. As long as there is no synthetic suture material with mild tissue reaction and late resorption the fascial closure should be sutured with polyester.

Microcrystalline collagen used in experimental splenic injury. A new surface hemostatic agent.

Microcrystalline collagen hemostat (Avitene) is a new surface hemostatic agent that is useful in the control of bleeding from the surfaces of solid viscera. In this study its efficacy was studied in experimental splenic injuries produced in dogs. Surface hemostasis obtained with this material appeared more effective and reliable than with other traditional hemostatic agents (absorbable gelatin sponge). Within five minutes of application to a surface splenic injury, complete hemostasis was obtained in 50 instances. No delayed bleeding was observed in any of the experimental subjects, nor were there other untoward reactions such as infection or excessive adhesion formation. Microcrystalline collagen is absorbed within six weeks, with minimal tissue reaction. The material was used successfully in one human case of iatrogenic splenic injury during a gastric procedure, averting splenectomy. No complications ensued.

Para-aortic node irradiation in carcinomas.

The authors have retrospectively analyzed the results of para-aortic node irradiation in 75 cases of metastatic carcinoma treated at the Department of Radiation Therapy, Roswell Park Memorial Institute, between 1963 and 1972. This group includes 62 patients with primary squamous cell carcinoma of the uterine cervix, 6 with adenocarcinomas of the sigmoid colon, 2 with adenocarcinomas of the endometrium, 3 with carcinomas of the vulva, 1 with adenocarcinoma of the ovary, and 1 with squamous cell carcinoma of the anus. The clinicopathologic behavior of para-aortic metastasis is studied in detail, including the relationship with the primary site, histologic grade, and degree of lymphatic invasion at the primary site. The group of cervical cancer patients seems to consist predominantly of those with advanced clinical stage, less differentiated tumors, endophytic or endocervical lesions, and those with endometrial or myometrial involvement. This study showed that the presence of metastatic carcinomas in the para-aortic nodes does not necessarily indicate the existence of more distant metastasis. These carcinomas can be safely irradiated and cured in a significant percentage of cases. Survival appears more favorable with higher radiation dosages. Six thousand rads delivered in 8 weeks, alone or concomitantly with pelvic irradiation, can be safely applied with minimal acute normal tissue reaction, and can eradicate the para-aortic node metastasis.

Polyglycolic acid sutures in genitourinary surgery

One hundred ten patients undergoing genitourinary surgery were sutured with PGA (polyglycolic acid) sutures. Seventy-one of these were also sutured with plain or chromic catgut, and/or nylon. There were no suture failures and no signs of wound breakdown. PGA sutures handled well, had minimal tissue reaction, and showed sufficient strength and knot security even in the presence of free-flowing urine. There was no superiority shown by the control sutures, and there appears to be no reason why PGA sutures should not be used in the urinary tract.

Intravasal Stents for Vasovasostomy in Canine Subjects

The feasibility of using absorbable suture material as an entire intravasal stent for vasovasostomy was investigated. Under general anesthesia 19 mongrel dogs were subjected to a 3- to 4-mm resection of the vas deferens with immediate reanastomosis. 4 different techniques were used. Group 1 dogs had vasovasostomies for which no stents were used. The anastomoses were performed with 6 sutures of 6-0 silk. Group 2 had vasovasostomies performed over intravasal stents of 3-0 Dexon and anastomoses were performed as in Group 1. Group 3 had vasovasostomies performed over 3-0 chromic catgut intravasal stents and anastomoses were carried out with silk as in Groups 1 and 2. Group 4 had vasovasostomies performed with chromic catgut intravasal stents as in Group 3 but the anastomses of the vas were carried out with 6-0 chromic catgut. All dogs were treated with penicillin and streptomycin for 5 days postoperatively. In Groups 1-3 the right scrotum was explored 3 months and the left 6 months after the anastomosis. In Group 4 all vasa were explored after 6 months. In all dogs vasography was carried out and sections for histopathologic study were obtained and prepared. The Group 1 over-all radiographic patency rate was 50%. The Group 2 rate was 60%. The Group 3 rate was 70%. In Groups 1-3 there were moderate to severe inflammatory reactions at the anastomotic line and nodular masses of varying sizes around the anastomoses. A patency rate of 90% was achieved in Group 4. In Group 4 there was minimal tissue reaction grossly at the anastomotic line and in several cases a careful search was required to find the exact area of anastomosis. These results indicate that chromic catgut is superior to silk for vas deferens anastomosis. They also demonstrate the feasibility of using absorbable intravasal stents.

Compatibility of Biomaterials

SUMMARY The advent of total hip replacement has presented new problems in the compatibility of biomaterials. For the first time, as many as three different materials are used in juxtaposition. Compatibility signifies that mutual interactions of the body and the implant cause little if any changes in either one. The stainless steel used for the manufacture of surgical implants in the United States is American Iron and Steel Institute type 316 with low carbon; similar steels are used in other countries. It is suited for such use by virtue of its physical properties, for it is more corrosion resistant in the body than stainless steel. Titanium and its alloys present high corrosion resistance with satisfactory physical properties although with a high coefficient of friction. The tissue reaction is minimal. Polymethylmethacrylate has poor impact strength but, acting as a grouting compound, is capable of holding prostheses in place. The tissue reactions include thermal injury and a reaction to the monomer and polymer that are more marked than that to metals. Ultrahigh molecular weight polyethylene is highly suitable as a bearing surface and in bulk causes a minimal tissue reaction. The long term compatibility of several materials in one prosthesis and to the small particles produced by wear is still unknown.

Immune Response of Pigs to Inactivated Foot-and-Mouth Disease Vaccines: Response to Emulsion Vaccines

The serological response of pigs to inactivated single and double emulsion foot-and-mouth disease (FMD) vaccines has been examined. The slopes of the dose-response regression lines for types A, O and C vaccines were low and only small amounts of antigen were required to elicit good immune responses. These vaccines resulted in granuloma and abscess formation at the site of injection. The extent of this reaction was dependent on the volume of vaccine administered. A reduction in the dose volume from 2 ml. to 0.25 ml. did not influence the immune response. The intradermal inoculation of 0·1 ml. of a type A double emulsion vaccine stimulated acceptable concentrations of circulating neutralizing antibody with minimal tissue reaction. The duration of immunity produced by emulsion vaccines was good, with neutralizing antibody concentrations remaining above the 50% protection level for 210 days in the case of a type O vaccine and for 280 days for types C and A vaccines. Pigs immunized with an emulsion vaccine showed good anamnestic responses to both emulsion and saponin adjuvauted vaccines. IgM was present for 42 to 63 days after primary inoculation, while IgG appeared at about 21 days after vaccination.

Clinical use of polyglycolic acid polymer as a new absorbable synthetic suture

The use of polyglycolic acid sutures was evaluated in 126 operations performed upon 118 unselected patients. The material appears to compare favorably with other sutures with respect to handling, tensile strength, knot security, lack of toxicity, and minimal tissue reaction. PGA did not interfere with wound healing, and the material was well tolerated in both clean and contaminated operations, including thirty-five operations in which PGA was used skin to skin. We believe PGA is the first practicable synthetic absorbable suture material. It is a nonproteinaceous, polymeric fiber which is predictably absorbed in vivo, and approaches the requirements of a “universal” suture material.

The behavior of biological materials at different sites of implantation.

AbstractAdult albino rabbits were implanted with disks of 316 and 304 stainless steel in the subperiosteum of the anterior calvarium and the left mandible and in the left paravertebral and thigh muscles. The corresponding opposite sites were sham operated. The histopathological slides revealed that there was variation in thickness of the membrane in sections of both the paravertebral and thigh muscles; one side showing greater reaction than the other, which corresponded with the appearance of the implants. Sections of the calvarium revealed minimal bone and soft tissue reaction, although the implants showed corrosion compatible with soft tissue sites. The mandibular sections revealed extensive bone tissue reactions with minimum masseter muscle reactions, but the appearance of the implants due to corrosion was different than those of all other sites. Moderate eosinophilic infiltration was observed in sections containing deposits of corrosion products.

Uterine histo-pathology in patients fitted with plastic intrauterine contraceptive devices.

To study the short-term histopathological effects of plastic intrauterine devices on the endometrium 4 patients scheduled for hysterectomy because of dysfunctional uterine bleeding had IUDs inserted preoperatively and curettage material was obtained from 4 patients with IUDs who were undergoing salpingectomy for permanent sterilization. Minimal tissue reaction was noted in the endometrium or myometrium of all patients except for mild surface inflammatory reaction at the site of pressure. In the hysterectomy specimens capillary dilatation with microscopic hemorrhage and thrombosis and stromal edema were also seen and stromal edema was again seen in 8 of the curettage cases. It was concluded that the short-term effect of plastic IUDs on the endometrial tissue is minimal.

Clinical evaluation of dacron suture material.

Dacron is a polymer of ethylene glycol and terephthalic acid. A number of experimental studies have demonstrated that it has good qualities for suture material and synthetic grafts.1-5It has greater tensile strength than silk or cotton, does not lose strength upon sterilization, and causes minimal tissue reaction. This report concerns its use as suture material in 747 operative cases. The sutures employed were closely braided, dyed with D and C green No. 6, and sterilized by electron sterilization.* There was no conscious case selection. The clinical material constitutes consecutive cases treated in the general surgical and cardiovascular sections and a substantial number in the thoracic section. There were 162 cardiac operations. Approximately half were open procedures employing total cardiopulmonary bypass. The remainder were closed procedures, such as mitral valvulotomies, division and suture of patent ductus arteriosus, repair of coarctation of the aorta, pulmonary valvulotomies, banding of the pulmonary

VINYON "N" AS DURAL SUBSTITUTE AND ITS USE IN OTHER NEUROSURGICAL CONDITIONS

The search for a material to be utilized as dural substitute has been a continuous one for the last six decades. Many materials have been tried, including the different metals, various biological tissues, and plant derivatives. Recently, synthetic products have been utilized as dural substitute. Among these, Vinyon N (Teng and Feigin, 1955), Teflon (Teng, unpublished data), and Orlon* (Huertas, 1955) have shown the most promising results, producing only minimal tissue reaction when buried intracranially in experimental animals. Since publication of the results obtained in experimental monkeys, Vinyon N has been used in 40 clinical cases with various neurosurgical conditions, which included its use as (1) dural substitute in repairs of dural defects produced by surgery, trauma, or tumour; (2) bone lining, in the prevention of bone reunion in craniostenosis; and (3) nerve wrap after neurolysis in cicatrization (Table I).

Complications from the use of absorbable hemostatic sponges.

<h3>Review of the Literature</h3> Since 1942 a large body of literature has grown around the use of the three types of absorbable hemostatic sponges which are now widely recommended and are the subject of this study: those made of fibrin (Fibrin Foam, Zimospuma); oxidized cellulose (Oxycel, Hemo-Pak, Zellurongaze), and gelatin (Gelfoam, Spongostan, Spongioprot, Topostasin). In 1945 Jenkins and Clark¹cautioned against the indiscriminate use of these materials. Frantz and associates²suggested in 1944 that oxidized cellulose be used "in as small quantity as possible." However, in 1946 Frantz³stated in a critical review of all three types of hemostatic sponges that there is no evidence of unfortunate late sequelae, and "they are all apparently safe and useful." The great majority of writers have emphasized the minimal tissue reaction, the rapid absorption, and the good hemostatic properties of these agents; in a review of the literature I found

Pathologic Study of Natural Amebic Infection in Macaques 1,2

Summary E. histolytica were found in the mucous membrane of naturally infected macaques. In all animals examined there were patchy, low-grade, chronic inflammatory reactions and scattered cystic and inflamed crypts of Lieberkuhn. The direct relationship of these abnormalities to the presence of the ameba was not positively established, although certainly there seemed to be an invasiveness of a low order. Usually the amebas lying in the tissues were associated with minimal tissue reaction. The amebas were located only in the mucous membrane layer and from their position would tend to support the idea that they first entered the tissues near the mouth of the cryptal glands where they passed directly into the interglandular papilla of the lamina propria. On the basis of these pathologic findings, it is our belief that naturally infected monkeys (Macacus rhesus) serve as suitable laboratory animals in the study of proposed amebacides.