74 THE NOSE AND PARANASAL SINUSES to remember that the returning fluid contains not only the material contained in the antrum but also the catarrh which may be lying in the nasal cavity. It cannot be used for bacteriological tests with the same accuracy as that obtained at aspiration, and it is less diagnostic of the source of the infected material. An antral lavage is a therapeutic measure in that it mechanically clears the infection from the maxillary antrum, and thus may cure a chronic infection. It may have to be repeated on several occasions before the returning fluid is clear, and this is usually done at weekly intervals. Accidents may occasionally complicate this simple procedure. If the maxillary sinus is small and narrow the trocar may be inserted with such force as to penetrate both medial and lateral walls of the sinus so that fluid is injected into the soft tissues of the cheek. This is recognized by pain and by the appearance of a swelling visible on the face. Such swelling soon resolves without incident if aseptic precautions have been observed. More un- commonly, but more seriously, the roof of the sinus may be punctured so that fluid is injected into the orbit with swelling and pain. Again this fluid is absorbed in time. These complications are more liable to occur if the puncture has been performed in children. TREATMENT. The principles of treatment of chronic sinusitis are: (i) the establishment of drainage from the infected sinus, which may provide a cure if the pathological changes in the sinus mucosa are reversible, and (ii) the surgical removal of infected mucosa when conservative therapy has failed or when the pathological changes are irreversible. Conservative therapy aims at the re-establishment of free drainage and the control of infection, and it is usually advocated in the first instance, especially in cases of relatively short duration. Antibiotics are given to combat the infection. If the organisms are known as, for example, when infected material has been cultured following a proof puncture, a course of the appropriate antibiotic is prescribed for 7 days. In some cases lavage may be continued through an indwelling polythene catheter during this time. If the infecting organisms have not been identified a broad-spectrum antibiotic may have to be used as the bacteriological flora varies considerably. Ampicillin is a suitable drug. Many of the cultures are staphylococcal, some of which are penicillinase producing in which event methicillin (Celbenin), cloxacillin (Orbenin) or flucloxacillin (Floxapen) must be used. Carbenicillin (Pyopen) is employed if the organisms are B.proteus, Esch. coli or pseudomonas which are penicillinase producing. In some resistant cases cephalosporin will have to be used as cephalexin (Ceporex or Keflex) but these should be reserved for particular cases and never employed as a first choice. In chronic cases in which there is no urgency about starting antibiotic therapy it is much more satisfactory to identify the strain and sensitivity of the infecting organisms at proof puncture before therapy is begun. Decongestion should be combined with antibiotic therapy, and this is achieved by nasal sprays or drops of 1 per cent ephedrine hydrochloride either alone or combined with 1 per cent silver protein (Argotone). Steam inhalations may also be used to promote drainage, and are given some 10 minutes after the decongestant spray. Short-wave diathermy is indicated at this stage, and the combination of decongestants, antibiotics, short-wave diathermy and antral lavage, if the maxillary sinus is involved, is frequently effective in curing the condition.