Granulation tissue

“ The best defined group is that of the granulomata, which includes such important diseases as tuberculosis and syphilis, and in which different types of chronic inflammation are caused by infection with a specific organism, all having the common character, however, that abundant granulation tissue is formed in which cellular changes are more in evidence than changes in the blood vessels, and in which the subsequent degeneration and necrosis of the granulation tissue results in the breaking down and destruction of the tissue in which it is formed. ”

“ They grow until they reach the level of the surrounding skin, and so fill the gap with a fine velvety mass of granulation tissue. At the edges, the young epithelium may be seen spreading in over the granulations as a fine bluish-white pellicle, which gradually covers the sore, becoming paler in colour as it thickens, and eventually forming the smooth, non-vascular covering of the cicatrix. ”

“ The area of coagulation necrosis becomes filled with white blood cells, and the dry necrosed part is liquefied by the cocci. Suppuration in dense structures causes considerable masses of tissue to die and to be cast off, and these masses float in the pus.
An abscess heals by the collapse of its walls, and the formation of an abundance of granulation tissue; in many cases granulations of one wall join those of the other side, the entire mass of granulations being converted into fibrous tissue, and this tissue contracting, heals by third intention. ”

“ The granulation tissue which forms as a result of the reaction of the tissues to the presence of the virus is chiefly composed of lymphocytes and plasma cells, along with an abundant new formation of capillary blood vessels. Giant cells are not uncommon, but the endothelioid cells, which are so marked a feature of tuberculous granulation tissue, are practically absent. ”

“ If the periosteum has been extensively destroyed, new bone may only be formed in patches, or not at all. The dead bone is separated from the living by the agency of granulation tissue with its usual complements of phagocytes and osteoclasts, so that the sequestrum presents along its margins and on its deep surface a pitted, grooved, and worm-eaten appearance, except on the periosteal aspect, which is unaltered. Ultimately the dead bone becomes loose and lies in a cavity a little larger than itself; the wall of the cavity is formed by the new case, lined with granulation tissue. ”

“ Larger bodies, such as needles or bullets, which are not capable of being destroyed by the phagocytes, become encapsulated. In the granulation tissue by which they are surrounded large multinuclear giant-cells appear (“foreign-body giant-cells”) and attach themselves to the foreign body, the fibroblasts proliferate and a capsule of scar tissue is eventually formed around the body. The tissues of the capsule may show evidence of iron pigmentation. Sometimes fluid accumulates around a foreign body within its capsule, constituting a cyst. ”

“ Large, black, dry eschars are formed, surrounded by a zone of intense congestion. Pain is less severe, and is referred to the parts that have been burned to a less degree. Infection is liable to occur and to lead to wide destruction of the surrounding skin. The amount of granulation tissue necessary to fill the gap is therefore great ”

“ When a localised portion of tissue, for example, a piece of skin, is so severely crushed or bruised that its blood vessels are occluded and its structure destroyed, it dies, and, if not infected with bacteria, dries up, and the shrivelled brown skin is slowly separated by the growth of granulation tissue beneath and around it. ”

“ If the lips cannot be drawn together and there be no surgical skill at hand to assist them with stitches or bandages, then the gap will be filled up by the fibrous transformation of this granulation tissue and a thick, heavy scar result. Meanwhile, the skin-cells of the surface have not been idle, but are budding out on either side of the healing wound, pushing a little line of colonists forward across the raw surface. ”

“ Any wound that suppurates much or sloughs causes a cavity to be filled up, and the process by which the wounds and sores heal is called granulation, and cicitrization. The wound is gradually filled up to the surrounding level by new tissue appearing in the form of small red granules bathed in pus. Healthy granulations on an exposed or flat surface rise nearly even with the surrounding skin, and often a little higher, but when they are much higher, and take on a growing action, they are what is called proud flesh. Their growth may be checked by the application of active astringents ”

“ This gap will necessarily be very small when the reflection of the mucous membrane has been complete. Where approximation of the two edges occurs union is rapid and healing by “first intention” results. Where some loss of substance occurs the gap becomes gradually filled by what is called granulation tissue, and the term “second intention” is given to the healing process.
Healing by first intention.
In amputating the foreskin a number of minute hair-like blood vessels which permeate the skin are [40] cut through. ”

“ When the infection becomes active, the contents of the cavity are transformed into a greenish-yellow pus from which the staphylococcus can be isolated, and the cavity is lined by a thin film of granulation tissue which erodes the surrounding bone and so causes the abscess to increase in size. If the erosion proceeds uniformly, the cavity is spherical or oval; if it is more active at some points than others, diverticula or tunnels are formed, and one of these may finally erupt through the shell of the bone or into an adjacent joint. ”

“ Accordingly, many abscess cavities resulting from deep-seated suppuration are of irregular shape, with pouches and loculi in various directions--an arrangement which interferes with their successful treatment by incision and drainage.
The relief of tension which follows the bursting of an abscess, the removal of irritation by the escape of pus, and the casting off of bacteria and toxins, allow the tissues once more to assert themselves, and a process of repair sets in. The walls of the abscess fall in; granulation tissue grows into the space and gradually fills it ”

“ The danger of infection is always great owing to: (a) presence of dead tissue; (b) the low resistance of adjacent sick tissue; (c) the open veins and lymph channels; (d) the adjoining skin which is difficult to sterilize; (e) the discharge of a large amount of serum which forms an excellent culture medium. There may be also severe hemorrhage as in any sloughing wound. The danger of this is greatly increased by infection, which breaks down the thrombi in the veins and arteries.
Stages of Granulation. The cavity left by the slough rapidly fills with new granulations. ”

“ Healing by second intention, or granulation, is usually seen where there has been loss of tissue, or extensive damage. The reactions of the tissues vary in degrees according to the nature and severity of the injury. In resenting such insults, a remarkable uniformity and regularity in the processes is brought about by the different cells and fluids of the healthy tissues of the body. ”

“ Skin grafting of granulating surfaces is chiefly employed to promote healing in the large defects of skin caused by severe burns; the grafting is carried out when the surface is covered by a uniform layer of healthy granulations and before the inevitable contraction of scar tissue makes itself manifest. Before applying the grafts it is usual to scrape away the granulations until the young fibrous tissue underneath is exposed, but, if the granulations are healthy and can be rendered aseptic, the grafts may be placed on them directly. ”

“ Never should so large a quantity of the mass be injected as to cause blanching of the narrow strip of skin. This is sure to result in gangrene of some, if not all, of the skin of the subseptum—a result much to be regretted, since subsequent correction of the deformity increased by the contraction of the dermal cicatrix is rendered well-nigh impossible by reason of this very tissue.
Hard paraffin injected in its molten state is never borne in this part of the human economy. ”

“ The mass after having been molded in the shape desired may be further hardened and set by the application of ice cloths or spraying with ether before the needle is withdrawn from the skin, yet this is hardly necessary, and the author advises against the practice for the reason that pressure of the needle prevents proper and free molding of the mass and renders the tissue liable to further injury by scraping its point to and fro subcutaneously, adding to the extent of the wound and the dangers of infection and repair. ”

“ A method that has proved of great value in America is that of skin-grafting in blood. In this method the grafted site is covered with perforated protective silk or rubber tissue, covered with a thin layer of absorbent cotton, or, better, several folds of sterilized gauze, which is kept wet constantly with bovinine. The latter undoubtedly is the means of keeping life in the grafts by supplying the necessary nutrition until the grafts have formed [91] vascular connection, have become firmly adherent, and begin to spread or grow out at their edges. ”

“ At the same time it must be remembered that the granulating process of repair is always more rapid upon the plantar cushion and fleshy sole than upon the bone, or upon tendinous or cartilaginous structures. As a result of this we have a wound showing various aspects of cicatrization. Healthy granulation may be profuse in one spot, while in another it may be checked either by a flow of synovia from the still open bursa, or by fragments of bone or of tendon still acting as foreign bodies in the wound. ”

“ Capillary loops grow into the coagulum, and migrated leucocytes from the adjacent blood vessels destroy the red corpuscles, and are in turn disposed of by the developing fibroblasts, which by their growth and proliferation fill up the gap with young connective tissue. It will be evident that this process only differs from healing by primary union in the _amount_ of blood-clot that is present. ”

“ When the action is more violent, and is not actively opposed, lymph is effused on the inner surface of the membrane, or is deposited amongst the ligamentous and cellular tissues external to the joint, in consequence of which, the membrane and external ligaments become thickened, and of an almost cartilaginous consistence. Serum is effused into the more superficial cellular tissue, filling up the hollows around the joint, concealing the protuberances of the bones, and producing a globular swelling. ”

“ Where there is loss of skin due to injury or operative procedure the parts may heal by granulation, but as this requires much time, and the consequent cicatrice causes considerable deformity, the granulating or freshly made wounds are covered with so-called detached skin flaps or grafts, when the former methods of plastic surgery cannot be followed. ”

“ For very small losses of tissue about the lobule nonpedunculated skin grafts are to be employed. The author advises including some of the areolar tissue with them to avoid contraction.
These are to be dressed with the blood method referred to under skin grafting. Perforated rubber tissue is to be used next to the epidermal surface to prevent the dressings from tearing away the graft when changed.
Fine twisted silk is most suitable for suturing purposes. The loops must not be drawn too tightly and the knot be made so that it rests upon the healthy skin of the nose. ”

“ When a muscle is paralysed from loss of its nerve supply and undergoes complete degeneration, it is not capable of being regenerated, even should the integrity of the nerve be restored, and so its function is permanently lost.
_Secretory Glands._--The regeneration of secretory glands is usually incomplete, cicatricial tissue taking the place of the glandular substance which has been destroyed. In wounds of the liver, for example, the gap is filled by fibrous tissue, but towards the periphery of the wound the liver cells proliferate and a certain amount of regeneration takes place. ”

“ Strenuous efforts must then be made to disinfect the trachea by the insufflation of antiseptics, either as powders or in solution. The healing of such ulcers is very slow, and granulations are apt to form resulting in obstruction and preventing removal of the tube. In later stages contraction of fibrous tissue causes stenosis; this is more common in the neighbourhood of the cricoid, especially when the latter has been divided at the time of the operation.
4. Granulations. The possible presence of granulations must always be borne in mind. ”

“ To assure the operator of a thorough dissection he may inject the site with sterile water through the opening made with the knife, squeezing it out before injecting the nose.
If the skin has had to be freed by surgical means the mass injected should be sufficient to overcome the defect almost entirely, to prevent the reformation of the bands of connective tissue which have been severed. ”

“ His method is now almost entirely used for covering large defects. The grafts can be applied over connective tissue, periosteum, bone, and even adipose tissue. The grafts consist of very thin strips of skin taken from the extensor surface of the arm or the anterior region of the thigh, after thorough antiseptic preparation. They should be taken from the patient in preference to those of other individuals or the new-dead or freshly amputated parts. ”