eMentorSurgery

Dear students, This is only for your revision and NOT A FULL TEXT.

Sinuses- (Latin a hollow; a bay or gulf)  &  Fistula

•        Blind track (usually lined with granulation tissue) leading from an epithelial surface into the surrounding tissues.

•        A sinus tract is anabnormal channel that originates or ends in one opening.

•        Pathological sinuses must be distinguished from normal anatomical sinuses (e.g. the frontal and nasal sinuses).

•          A fistula is an abnormal pathway between 2anatomic spaces or a pathway that leads from an internal cavity or organ to the surface of the body.

•        An orofacial fistula is a pathologic communication between the cutaneous surface of  the face and the oralcavity.

•        May be congenital or acquired.

•        Congenital origin

       Preauricular sinuses ,

       Branchial fistulas,

      Tracheo-oesophageal fistulas  and

       Arteriovenous fistulas.

The acquired forms 

      Following adequate drainage of an abscess.

      A perianal abscess may burst on the surface and lead to a sinus

      Opens both into the anal canal and on to thesurface of  the perineal  stem resulting in a true fistula-in-ano.

     Acquired arteriovenous fistulas -by trauma or surgical procedures  (for renal dialysis).

 Fistulas- A fistula (Latin = a pipe or tube)

•        An abnormal communication between the lumen or surface of one organ and the lumen or surface of another,or between vessels.

•        Most fistulas connect epithelial­ lined surfaces.

 An oro-facial fistula

•        Is a pathologic communication between the cutaneous surface of the face and the oral cavity.

•        Pathophysiology: Origins and spread, salivary gland fistul as, oral antral and oral nasal fistulas,iatrogenic such as dental implant placement, and miscellaneous or a cutaneous fistulas.

 Persistence of a sinus or fistula

A foreign body or necrotic tissue is present, e.g. asuture, hairs, a sequestrum, a faecolith or even a worm.

•  Inefficient or nondependent drainage: long,narrow, tortuous track predisposes to inefficient drainage;

•  Unrelieved obstruction of the lumen of a viscus or tube distal to the fistula;

•  High pressure, such as occurs in fistula-in-ano due to the normal contractions of the sphincter which force faecal material through the fistula;

•  The walls have become lined with epithelium or endothelium(arteriovenous fistula);

•  Dense fibrosis prevents contraction and healing;

•  Type of infection, e.g. tuberculosis or actinomycosis;

•  The presence of malignant disease

•  Ischaemia;

•  Drugs, e.g. steroids, cytotoxics;

•  Malnutrition;

•  Interference, e.g. artefacta;

•  Irradiation, e.g. rectovaginal fistula after treatment for acarcinoma of the cervix;

•  Crohn’s disease;

• High-output fistula, e.g. duodenocutaneous fistula.

 Treatment 

  The remedy depends upon e removal or specific treatment of the cause

 Guinea worm (syn. dragon worm, Dracunculus medinensis)

•        A persisting sinus on the leg.

•         The larval formenters through the wall of the stomach or duodenum in drinking water contaminated by a tiny cyclops crustacean which has consumed the larvae.Settling in the abdominal connective tissue, the male and female mate, the pregnancy lasting about a year, and the female wanders in the subcutaneous tissues to select for egg laying a part of the anatomy likely to be submerged in water(containing the cyclops), usually the leg. Cellulitis, abscesses, ulcersand sinuses follow, through which the embryos are discharged, hopefully to beeaten by the cyclops.

 Thyroglossalfistula

•        never congenital:

•        Follows infection or inadequate removal of a thyroglossal cyst.

•        Characteristically the cutaneous openingof such a fistula is drawn upwards on protrusion of  the tongue.

•        A thyroglossal fistula is lined by columnar epithelium, discharges mucus, and is the seat of recurrent attacks of inflammation.

•        Infected cysts may be wrongly diagnosed as an abscess & drained.

•        This leads to Thyroglossalfistula-  which is  never congenital 

•        They often present after an upper respiratory infection.

 Treatment-Surgery

Sistrunk’s operation

                        Recurrenceis  3- 5%

                       Removalof part of hyoid bone

 Sistrunk’soperation

The hyoid bone, this central part must be excised, together with the cyst or fistula, or recurrence is certain. When the thyroglossal tract can be traced upwards towards the foramen caecum, it must be excised with the central sectionof the body of the hyoid bone, and a central core of lingual muscle.

 Principles involved in management of Thyroglossal cyst

•        Thyroid Scan

•        To see ---- is it the only  functioning thyroid tissue ?

Salivary gland fistulas

•        Rare except with minor salivary gland mucocele.

•        Saliva from damaged glands or ducts finds pathway.

•        The parotid duct or Stensenduct comes close to the cutaneous surface as the duct crosses the outer surfaceof the masseter muscle.

•        A rare submandibular fistula was reported in association with a ranula of the submandibular gland. 

•        Mimicked a branchial cleft,branchial cyst  fistula & branchial fistulas.

•        Trauma, microorganisms,neoplasms,xerostomia, immunosuppression, and malnutrition usually are the cause of  infections that result in fistulas.

 Oral  antral and oral nasal fistulas

 •        Tooth extraction,tuberculosis,syphilis, leprosy, malignant neoplasms, phycomycoses, midline granuloma (a formof lymphoma), and developmental clefts may cause oral antral and oral nasal fistulas.

•        The most common cause of oral antral fistulas is tooth extraction.

•        Maxillary first molars account for 50% of oral antral

 Lab Studies

•        Culture and sensitivity testing and, in selected cases, DNA probe testing may be used to identify the causative organism and determine treatment.

•        Serious dental infections may increase  E.S.R and neutrophil count.With chronic infections,lymphocyte and monocyte counts may subsequently increase.

Imaging Studies

•        In chronic periapical infections, a well-circumscribed radiolucency-observed radiographically;  in early infections, -not be observed.

•        On radiographs, osteomyelitis appearsas an area of radiolucency, radiopacity, or mixed radiolucency with poorly defined borders.

•        The mandible is most commonly involved.

•        These findings are also present in osteo radionecrosis

•        If infection persistsd espite therapy, CT and MRI may be necessary to determine its extent and to rule out an eoplastic cause.

•        Fistulogram &Sinogram:Injection of contrast into the opening of sinus or fistula and then radiographs to be taken.

•        Panoramic radiographs,lateral jaw plain radiographs, Waters radiographs, or periapical radiographs may be necessary  for diagnosis and treatment, depending on the location and extent of the infection.

•        With oral antral and oral nasal fistulas, cloudy sinuses may be observed on panoramic or Waters radiographs.Radiographs occasionally show a break in the antral or nasal floor.If the opening to the palate is large enough, nasal speech occurs.

Medical Care

•        To properly treat any infection,

•        Drainage is necessary to decrease the number of microbes and reduce the amount of substrate on which they grow.

•        Antibiotic coverage is necessary to eliminate or reduce the number of microbes causing  the infection.

•        With most dental infections,penicillin is the drug of choice. Penicillin and amoxicillin with orwithout clavulanic acid are administered empirically to treat  the infection before culture and sensitivity results are available.

•        Amoxicillin is often used because of its rapid absorption in the gastrointestinal tract. Amoxicillin with clavulanic acid (Augmentin) is effective in broad-spectrum infections withbothgram-positive and gram-negative organisms.

•        Doxycycline is effective in the treatment of periodontal disease.

•        The combination of amoxicillin and metronidazole is also effective in treating severe periodontitis inindividuals who are HIV positive.

•        Intravenous medications thatare useful in the treatment of serious facial and orbital infections include nafcillin; cefazolin; ceftriaxone; vancomycin; levofloxacin;andbeta-lactam/beta-lactamase inhibitors, including piperacillin/tazobactam,ticarcillin/clavulanate, and ampicillin/sulbactam.

•        The treatment of osteomyelitis and actinomycoses infections

–       The removal of sequestered or necrotic bone also is indicated.

–       Hyperbaric oxygen

–       Surgical Care