Clinical Techniques: When and how to do a myringotomy – a practical guide

A myringotomy is a surgical incision made in the tympanic membrane (TM). This gives access to middle ear for sampling, flushing and instilling topical therapy. It should be considered whenever TM intact there clinical evidence of otitis media, abnormal TMs and/or diagnostic imaging. Samples collected cytological investigation culture, then external cleaned dried (if required). Myringotomies performed under general anaesthesia and, wherever possible, using video otoscope; enhanced view instrument ports facilitate technique reduce risk complications. The caudoventral quadrant an appropriately sized urinary catheter collect samples flush cavity. thorough understanding anatomy, potential ototoxicity therapy needed minimize neurological other usually heals within 35 days if kept free infection. Une myringotomie est une chirurgicale de la tympanique Elle donne accès à l’oreille moyenne pour prélèvement, et traitement topique. doit être envisagée même si intacte il y des signes cliniques évocateurs d’otite moyenne, anormale et/ou un anormal d’imagerie. Les échantillons devraient collectés cytologie ainsi externe devrait nettoyée séchée (si besoin). myringotomies réalisées sous anesthésie générale possible l’aide d’un vidéo-otoscope; l’amélioration visualisation du port instruments facilitent réduit le risque L’incision réalisée dans cadrant caudo-ventral d’une sonde urinaire diamètre approprié collecte nettoyage bulle tympanique. meilleure connaissance l’anatomie, potentielle ototoxicité topique nécessaire minimiser complications, notamment, neurologiques. La Tm cicatrise habituellement en jours aucune infection n’est présente. Una miringotomía es una incisión quirúrgica realizada membrana timpánica Esto da acceso al oído medio para tomar muestras, lavar e introducir terapia tópica. Se debe considerar siempre que esté intacta haya evidencia clínica anormales y/o imágenes diagnóstico anormales. deben obtener muestras investigación citológica cultivo, luego se limpiar secar el externo necesario). Las miringotomías realizarse bajo anestesia y, sea posible, utilizando otoscopio; mejor visualización los enlaces instrumentos facilitan técnica reducen riesgo complicaciones. cuadrante catéter urinario tamaño apropiado recolectar cavidad del medio. necesita conocimiento profundo anatomía, posible ototoxicidad tópica minimizar complicaciones neurológicas otro tipo. generalmente cicatriza días mantiene libre infección. Eine Myringotomie ist eine chirurgische Inzision am Trommelfell Diese ermöglicht einen Zugang zum Mittelohr, um Proben zu nehmen, spülen oder topische Medikamente applizieren. Sie sollte immer Betracht gezogen werden, wenn das intakt und klinische Evidenz für Mittelohrentzündung, abnormale und/oder bildgebende Diagnostik vorliegen. Die sollten zytologische Untersuchung Kultur genommen danach äußere Ohr gereinigt (wenn nötig) getrocknet werden. Myringotomien unter Vollnarkose möglich mittels Video Otoskop durchgeführt werden; die erweiterte Sicht Instrumentenzugänge erleichtern Technik reduzieren Risiko von Komplikationen. im caudoventralen Quadranten erfolgen, wobei ein entsprechend großer Katzenharnkatheter zur Probenahme Spülung Mittelohrs Verwendung finden sollte. Ein genaues Wissen der Anatomie, möglichen Ototoxizität topischen Therapie Voraussetzung, einer neurologischen anderen Komplikation minimieren. Das heilt normalerweise, Infektion verhindert wird, innerhalb Tagen zu. ??????, ??(TM)???????????????????????, ??????????????, ??????, ??????, ???????????????????????????????????????????????????????????????????????????????????????????????????????? (?????) ?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????TM???35????????? ?????????(TM)???????????????????????????????TM????????TM???/?????????????, ???TM????????????????, ?? (???) ????????????????????????, ??????????????????; ????????????????, ?????????????????????TM?????????????, ???????????????????????????????????, ?????????????????????????,TM???35????? miringotomia é uma incisão cirúrgica na timpânica (MT) dá acesso ao ouvido médio coleta amostras, limpeza instilação deve ser considerada sempre MT está há evidência otite média, MTs anormais e/ou exame imagem anormal. As amostras devem coletadas investigação cultura, depois o limpo seco (se necessário). Miringotomias realizadas sob geral e, possível, vídeo otoscópio; visão ampliada as portas facilitam reduzem risco complicações. no quadrante cateter urinário tamanho apropriado coletar cavidade do médio. Um conhecimento aprofundado anatomia, potencial ototoxicidade produtos tópicos necessário complicações outra natureza. geralmente em dias mantida sem infecção. Otitis media common potentially underdiagnosed.1 Infectious occurs 50–82% dogs with chronic recurrent externa, particularly where horizontal canal stenosis Gram-negative bacteria.2, 3 While majority these cases were progression externa through perforated (TM), several had tympanum that was thought have healed over active media.3 sterile form, primary secretory (PSOM) or effusion (OME), recognized cavalier King Charles spaniels (CKCS) initially, although it can affect any brachycephalic breed. may present ?70% CKCS without associated signs.4 cats most commonly presents result nasopharyngeal polyp (NPP), from pharyngeal upper respiratory which has extended up auditory (Eustachian) tube, following tube dysfunction obstruction, mucositis/sinusitis. Less commonly, extension also been suggested cause could haematogenous spread.5 signs overlap externa. make diagnosis challenging. Clinical include head shaking, scratching rubbing ear, dullness, avoiding contact (e.g. petting), exudates, reluctance eat hard foods, pain on opening mouth, odour. In addition, lead interna such tilt deafness. Horner’s syndrome more due superficial anatomy their sympathetic trunk. Peripheral vestibular (i.e. tilt, ataxia nystagmus) facial nerve deficits occur advanced severe treated emergency. Otoscopic examination reveal (Figure 1). Changes thickened, opaque, inflamed grey TM, material behind convex pars tensa. see ruptures tears typically (in absence traumatic iatrogenic damage TM) confirms media. However, small are almost impossible magnified image high-quality otoscope. Moreover, some only become visible when they open during procedures. Even otoscopy, debris limit TM. bulging flaccida obscuring all tensa PSOM 1b), flat does not rule out 2).4 Examples membranes (TM) justify (top = dorsal; bottom ventral; left rostral; right caudal). (a) Material cat inflammatory polyp. (b) par spaniel (c) opaque into dog infective Compare normal appearance Figure 5. Diagnostic imaging [e.g. computed tomography (CT), magnetic resonance (MRI) radiographs] indicated suspected. CT preferred by authors, sensitive specific changes bony structures ear.6 Abnormal findings (including soft-tissue bullae bulla wall) confirm 3). (especially plain radiography, less sensitive) out. Computed scan opacities both ears. Hounsfield unit scale density analysis fluid ventromedial compartments (solid arrow) soft tissue dorsolateral (open arrow). Note complete shelf compare this incomplete illustrated Figures 6 7. allow entry ear. used presence remove exudates cavity, obtain evaluation microbial drain instill otic one present: Oral glucocorticoids two three weeks initially hyperplastic stenotic canals, except circumstances systemic use contraindicated. requires involves risks. Patients stabilized before procedures, taking account concomitant conditions. patient must intubated secure endotracheal prevent aspiration drainage. room set otoscope anaesthetic 4), patients placed lateral recumbency medically approved heating pad affected uppermost, completely clean evaluate Where neck slightly elevated positioned at downward angle drainage nose mouth. reduces case inadequate seal around tube. Other equipment materials listed Table 1. Room set-up flush. 1, Monitor; 2, light source; 3, digital capture system; 4, camera box; 5, device [VETPUMP 2 (box, glass canisters handpiece)]; 6, attached otoendoscope source Mayo stand; 7, defogging agent (UltraStop); 8, medically-approved pad; 9, tub table (Midmark Canis Major Wet Dental/Treatment Lift Table); 10, stools Dental Stools clinician technician). Possible complications syndrome, paralysis, disturbances, permanent defects Owners aware giving informed consent. instructed watch after procedures treatment. They discontinue treatment clinic immediately occur. These normally resolve four yet permanent. important familiar ear.7, 8 semitransparent separating sections: smaller larger lower manubrium malleus attaches medial surface externally stria mallearis 5). Normal canine (right ear). A, Pars flaccida; B, tensa; C, caudal; rostral). consists mucosal-lined air-filled cavity ossicles (malleus, incus stapes) 6). Rostrally, connected nasopharynx dorsal epitympanic recess, proper ventral largest cavities part bulla. There ridge (septum bulla) separates cats, (dorsolateral ventromedial) making pass compartment septum allowing whole On wall opposite eminence, promontory, houses cochlea. foramens promontory; caudolateral round window oval window. latter adjacent covered thin diaphragm footplate stapes 7). Anatomy inner structures. Arrows indicate region (facial) exposed caudal stapes. dogs, fibres run carotid petrous temporal bone; form plexus cochlear promontory between windows (see (© Tim Vojt). Bony outline superimposed (broken white lines). lines) outlined feline similar divides compartments. runs windows. yellow circle highlights site – avoids rostral dogs) affords (D, V, R, nerves enters internal acoustic meatus travels tunnel, canal, bone. An therefore infiltrate connective paralysis. expose media-associated deficits, described rare unless destruction involving canal. ascending vestibulocochlear resulting interna. branch, chorda tympani, exits passes beneath base medially, close flaccida, merge lingual branch cranial V innervate third tongue. traumatic/surgical rupture impair taste. Another greater petrosal nerve, provides innervation lacrimal nasal glands. Damage neurogenic keratoconjunctivitis sicca (KCS) dry (xeromycteria) Post-ganglionic cervical trunk located dorsomedial bone artery enter overlying promontory. consequence course species (Figures When performing myringotomy, avoid damaging windows, necessary amplification transmission sound waves function ocular innervation. Because mid-dorsal aspect dorsorostrally required accuracy greatly facilitated good-quality osseous For infectious obtained clinically indicated, culture antibiotic susceptibility testing (AST) flush,9 soaked 10 min non-ototoxic ceruminolytic cleaner squalene) patency unknown. flushed warm 0.9% saline bulb syringe large exudate. followed handheld (Table Once clean, suctioned ear; drying contamination myringotomy. canals dry, visualized, ideally very difficult assess integrity perform accurate If intact, bacterial AST directly passing 5 French polypropylene red rubber feeding 12 cc/mL channel keep position floor 8). gentle direct aspirated back. container AST. second sample evaluation. gently repeatedly approximately 1 mL (cut appropriate length 30 cm; cut 90° sharp edges smoothed trauma epidermis mucosa) suction irrigation device. essential mucus, pus, cleaning fluids canals) removed. Finally, residual aspirated. Clinician (right) technician (left) dog’s setup shown 4. placement screen image. done catheter. authors’ opinion, instruments, needle laser, too incision, spinal needles buck curettes down incision. keeping conformation deviation proximal pugs bulldogs) visualize correctly align ”blind” ”off-target” “aiming” towards tensa, increases Alternatively, procedure abandoned approach considered. made, until encountering (bulla septum) solid backed off begin suctioning. above. necessary, initial enlarged retrograde flow material. Over-vigorous adequate space efficient build-up pressure causing uncontrolled tear) above 9). so obscures To slipped directed made. visualizing easier puncturing deflating even though results being expelled simultaneously Contamination post-myringotomy concern. study cadavers, fluorescein-stained noted 19 28 (68%) positive growth 11 (9%) ears corresponding cultures.10 first cultured, infected, rate higher. healthy concurrent externa) would appear low, clinicians much significant thoroughly micro-organisms area. will introducing saline, Topical instilled choice medication depend type infection; however, ointment- suspension-based otics avoided. continued home, unclear how penetrate therefore, sufficient volume used. likely penetrate, selecting 21 days,11 perforation healing take 15 weeks.12 Therefore, procedure, heal. Nonhealing defect complication. abnormalities Myringotomy flushing/aspiration evaluation, ASTs, mucus. Good relies positioning careful otoscopes authors grateful Vojt drawing Please note: publisher responsible content functionality supporting information supplied authors. Any queries (other than missing content) author article.