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•Pathogenesis •Classification •Complications Vishav Yadav 1 Keratin-producing squamous epithelium in the middle ear, mastoid or petrous apex Johannes Müller (1838):German Physiologist coined cholesteatoma i.e. layered paerly tumpour of fat Schuknecht : keratoma 2 Abramson 3D epithelial and connective tissue structure usually in form of sac , mostly confined to middle ear spaces , with tendency of independent growth on cost of underlying bone , with tendency of recurrence despite complete removal . 3 Histologically made up of : Cystic content – anucleate keratin squames Matrix – keratinizing squamous epithelium Perimatrix – granulation tissue in contact with bone (produces proteolytic enzymes) 4 Congenital Acquired Primary acquired (retraction pocket) Secondary acquired Tertiary acquired 5 6 The incidence of CC - 1% to 5% of all cholesteatomas Congenital cholesteatoma of the middle ear was first described by Howard House Location (AS,PS , petrous pyramid, mastoid and middle ear cleft , CP Angle) 7 Levenson criteria (Modified Derlacki & Clemis) White mass medial to normal TM Normal pars flaccida and tensa No history of otorrhea or perforations No prior otologic procedures Prior bouts of otitis media not grounds for exclusion 8 The accepted cause of CC remains controversial Teed’s epithelial cell rest theory Friedberg’s implantation theory Ruedi’s invagination theory Aimi’s epithelial migration theory Michael’s epidermoid formation theory 9 Most commonly accepted and quoted theory Teed An epidermal structure : these rests as ectodermal implants in the fusion plates between the first and second branchial arches that appear around 10 weeks It aided in middle ear and tympanic membrane development. Initially dormant, it undergoes rapid proliferation before resorption around 33 weeks’ gestation CC is thought to form if resorption is incomplete 10 Friedberg observed viable squamous cells in the amniotic fluid present in the middle ear of neonates. Could they be a cause for congenital cholesteatoma? 11 Ruedi Inflammatory injury to an intact tympanic membrane Microperforations in the basal layer that lead to invasion of the squamous epithelium by proliferating epithelial cones through a macroscopically intact but microscopically injured tympanic membrane. Epithelial cones fuse and expand forming a middle ear cholesteatoma 12 First proposed by Aimi He suggested that ectoderm of external canal managed to grow / migrate in to the middle ear cavity somehow overcoming the restraining influence of the annulus. 13 First proposed by Michael He observed nests of squamous epithelium in the lateral wall of tympanic cavity below the level of pars flaccida These nests normally involute Failure of this involution process can possibly cause cholesteatoma 14 15 (1) aid the clinician in preoperative planning of treatment (2) Indicate prognosis (3) facilitate exchange of information between different clinicians (4) evaluate the results of treatment. 16 Petrous Pyramid Mastoid Tympanic 17 Stage 1: Single quadrant with no ossicular or mastoid involvement Stage 2: Multiple quadrants with no ossicular or mastoid involvement Stage 3: Ossicular involvement but no mastoid involvement Stage 4: Mastoid extension 18 Type 1: Mesotympanum with no incus or stapes erosion Type 2: Mesotympanum or attic with ossicular erosion but no mastoid extension Type 3: Mesotympanum with mastoid extension Clinical Stage Recurrence Rates TYPE 1 15 0 TYPE 2 59 34 TYPE 3 26 55 19 20 Invagination theory of Wittmaack Eustachian tube dysfunction Poor aeration of the epitympanic space Retraction of the pars flaccida Normal migratory pattern altered Accumulation of keratin, enlargement of sac 21 Basal cell hyperplasia (Ruedi theory) Inflammatory injury to an intact tympanic membrane Microperforations in the basal layer that lead to invasion of the squamous epithelium by proliferating epithelial cones through a macroscopically intact but microscopically injured tympanic membrane. Epithelial cones fuse and expand forming a middle ear cholesteatoma 22 Squmaous metaplasia (Sade theory) transformation of cuboidal epithelium to squamous epithelium from chronic infection 23 Presence of preexisting perforation in pars tensa Often associated with posterosuperior marginal perforation or large central perforation 24 Immigration & Invasion: Habermann medial migration along permanent perforation of TM Implantation & invasion –foreign body, blast injury Metaplasia – transformation of cuboidal epithelium to squamous epithelium from chronic infection Papillary ingrowth – intact pars flaccida, inflammation in Prussack’s space, break in the basal membrane, cords of epithelium migrate inward 25 iatrogenic – surgery, foreign body, blast injury Tympanoplasty Ossiculoplasty Stapedotomy Typmpanostomy tubes 26 27 Epitympanic cholesteatoma patterns of spread from Prussack’s space Posterior epitympanum Posterior mesotympanum Anterior epitympanum 28 Medially :neck of malleus laterally :Shrapnell’s membrane Sup : lat malleal fold Anteriorly anterior malleolar fold & anterior ligament 30 Posterior epitympanum – through superior incudal space to mastoid antrum 31 Posterior mesotympanum – inferiorly through posterior pouch of Von Troeltsch to stapes, round window, sinus tympani and facial recess 32 Anterior epitympanum – anterior to head of malleus, may gain access to supratubal recess To ant mesotympanum via anterior pouch of von Troeltsch 33 *Medially – Medial Wall Of Middle Ear with Oval & Round Window Niches *Laterally – Pyramid & Facial Nv *Superiorly– Ponticulus *Inferiorly – Subiculum -can extend as far as 9mm into the mastoid -probably the most inaccessible site in middle ear & mastoid Molecular models Preneoplastic transformation events Defective wound-healing process Collision between host inflammatory response, normal middle ear epithelium, and bacterial infection 35 Hyperproliferative keratinocytes Increased proliferation Decreased terminal differentiation Expression of epithelial markers in the basal and suprabasal layers (cytokeratins –10,13,16, filaggrin, involucrin); confirm they arise from pars flaccida and overlying EAC skin High expression of epidermal growth factor receptor, transforming growth factor Upregulation of p53 36 Chronic inflammatory response around matrix (granulation/perimatrix) Infiltration of activated T-cells and macrophages Production of cytokines (TGF,TNF,IL-1,IL2,FGF,PDGF) Causes increased migration and invasion of cholesteatoma epithelium and fibroblasts 37 Bacterial related antigens producing host inflammatory response may stimulate the migrating epithelium’s uncoordinated proliferation Granulation induces invasion of keratinocytes Granulation – contains proteases, acid phosphatases, bone resorption proteins, osteoclast-activating factors, prostaglandins 38 39 Intracranial Extradural abscess Subdural abscess (empyema) Sigmoid sinus thrombophlebitis Meningitis Brain abscess Otitic hydrocephalus 40 Intratemporal Facial paralysis Labrynthine infections Labyrinthine fistula Petrositis Mastoiditis Other rare complications: Abscess: Bezold’s abscess Luc’s abscess Citeli’s abscess Distant pyaemic abscess Extratemporal complications: Subperiosteal abscess Migrating thrombophlebitis of IJV Migrating thrombophlebitis of IJV 41 Possible routes of spread: Extension through bone Infected clot within small veins Normal anatomical pathways Non anatomical bony defects Surgical defects Into brain tissue along periarteriolar spaces of Robin Virchow 42 General principles: The complications are multiple in about 1/3rd of the cases The symptoms of intracranial spread of infection are those of infection and those of brain tissue compression Otalgia is never a symptom of uncomplicated cholesteatoma Investigation and treatment must run concurrently The principles of treatment : Systemic antibiotic therapy Local neurosurgical attention to the complication(s) Treatment of the ear lesion 43 Intracranial complication: G-ve organisms Staphylococci- beta lactamase producing Obligate anaerobes Bacteroides fragilis Extratemporal and temporal complications: Pseudomonas Proteus 44 High grade fever Headache with vomiting Copious ear discharge Gait changes Visual alterations Seizure activity Neck stiffness Unusual persistent pain 45 Etiology :Bone erosion Sigmoid perisinus abscess 46 47 Clinical features: Site and size Duration and rate Incidental finding Headache with malaise Intermittent relief from pain during episodes of aural discharge Diagnosis : Operative findings CT scan 48 49 Management : Surgical exploration ????Don’t remove the granulation tissue attached to the dura Appropriate antibiotics 50 Spread of infection Loculated infection Thrombophlebitis Obliteration of subdural space Commonly associated organisms: Strp. milleri H. influenzae 51 52 Clinical features: Severe headache Fever Drowsiness Focal neurological deficit Seizure Paralysis The course is much more rapid than brain abscess Papilledema is uncommon, as are the cranial nerve palsy Seizures and FND differentiates from meningitis 53 Diagnosis CT scan MRI LP : helpful but risky ↑pressure Normal sugar content Cultures are sterile Marked pleocytosis 54 Management : Removal of subdural fluid Massive antibiotics Treatment of ear disease Antiepileptics 55 Lateral sinus : Sigmoid sinus Transverse sinus Usually preceded by the development of extradural perisinus abscess Spread of infection Torcula herophili (confluence of sinuses) Superior sagittal sinus Superior and inferior petrosal sinus Cavernous sinus Brain abscess Internal jugular vein Subclavian vein 56 57 58 Commonly associated organisms: Beta hemolytic streptococci Staphylococus aureus Now a days : mixed flora : Venezio et al in 1982 grew Proteus mirabilis, staphylococci, streptococcus pneumoniae and Bacteroides oralis 59 Clinical features: Classical picture before antibiotics: Spread along the IJV: Severe pyrexial wasting illness Develop over several weeks Picket fence fever Headache and neck pain Emaciation with anaemia Perivenous inflamation Perivenous edema Suppuration of the lymph node Paralysis of the lower cranial nerves ↑ICP Hydrocephalus Superior extension Superior sagittal sinus Cavernous sinus 60 Septic embolisation (sinus thrombophlebitis) Lung fields Large joints Subcutaneous tissue Other viscera Pleuroperitoneal cavity Mastoid emissary vein: suboccipital abscess Griesinger’s sign: oedema of the postauricular soft tissues overlying the mastoid process as a result of thrombosis of the mastoid emissary vein 61 Investigations : Hemogram Blood cultures Lumbar puncture : Low WBC count Normal CSF pressure Queckstedt or Tobey-Ayer test CT scan: An empty triangle at the level of the sigmoid sinus, clot surrounded by a high-intensity rim of contrast-enhanced dura: delta sign Angiography Venography MRI 62 •The jugular vein on the side of the suspected thrombosis is compressed • A rise in spinal fluid pressure should occur •Its absence indicates presence of thrombosis. 63 64 65 Treatment : Administration of antibiotics Exposure of the sinus: incision and removal of contents Perisinus cells need to be cleared: chances of delayed sinus thrombosis if not cleared ???? Anticoagulants : If in spite of the treatment the infection is progressively involving the cortical veins Role of IJV ligation: if the thrombus is getting dislodged then the need to ligate IJV 66 The commonest intracranial complication Childhood otogenic meningitis is seen most often as a complication of acute middle ear infection In adults, it is now more commonly a complication of chronic disease 67 Pathways of spread: Bone erosion Suppurative labrynthitis Rupture of established brain abscess Organisms responsible for acute infection: Hemophilus influenzae type B Streptococcus pneumoniae type III Organisms responsible in chronic infection: G-ve enteric organisms Proteus Pseudomonas Anaerobes such as Bacteroides species 68 Clinical features: Headache and neck stiffness Malaise Pyrexia mental hyperactivity Exaggerated Tendon reflexes Photophobia Vomiting 69 Diagnisis : Lumbar puncture Rise in fluid pressure above the normal 100-150 mm Hg Gross appearance of fluid: cloudy and then turbid On histological inspection PMN cells ranging from 0.1-10x109 /l Biochemical tests: Bacteriological examination : gram staining and then culture D/d : Protein content may rise from normal of 150-400mg/l to a raised level of 2-3g/l Chloride content may fall from the normal 120mmol/l to 80mmol/l Fall in glucose level from the normal value of 1.7-3.0 mmol/l to zero Rupture of brain abscess Rupture of subdural abscess CT scan MRI PCR 70 Treatment : Medical : Repeated LP to lower the raised pressure Large doses of systemic antibiotics Systemic antibiotics must continue for 10 days after apparent clinical recovery Dexamethasone?? Surgical : Certainly deterioration or failure of response over 48hrs implies loculated infection in the mastoid, needing surgical drainage 71 72 Failure of an adequate response to antimicrobial therapy may be a result of : Organism resistant to chosen antibiotics Persistent leakage of infected material into the CSF Persistence of a previously unidentified other complication/Leakage into the CSF from an unrecognized brain abscess. 73 It is a focal suppurative process within the brain parenchyma serrounded by a region of encephalitis. Bimodal age of distribution with peaks in the paediatric age group and in the 4th decade of life. Almost always develop in the temporal lobe or the cerebellum Temporal lobe abscess is twice as common as cerebellum 74 Various routes of spread: Through an osteitic tegmen tympani , with middle fossa extradural abscess Local pachymeningitis followed by thrombophlebitis Extension of infection along periarteriolar Virchow-Robin spaces Cerebellar abscess are frequently preceded by lateral sinus thrombophlebitis 75 76 Bacteriology :polymicrobial (also extradural) Anaerobes Streptococcus & staphylococcus G- organism: Escherichia coli Proteus Klebsiella Pseudomonas 77 Clinical presentation: Very toxic and drowsy Brain abscess is associated with the triad of: Headache High grade fever Focal neurological deficits Cerebellar abscess: Dizziness Ataxia Nystagmus Vomiting Temporal lobe lesion: Seizure Visual field defects Nominal aphasia 78 79 Diagnosis : Imaging : Computed tomography Hypodense area by an area of edema, ring sign MRI: superior to CT scan except for delineation of temporal bone is poor. 80 81 82 Other d/d: Meningitis Subdural abscess Lateral sinus thrombophlebitis Otitic hydrocephalus Other masses such as brain tumour. 83 Management : High-dose antimicrobial medication Patient should be first stabilized neurologically: ? Aspiration with high dose of antibiotics ?Total excision ?parenteral antibiotics 84 Syndrome (pseudotumour cerebrii) associated with otitis media with Increased intracranial pressure Normal CSF findings Spontaneous recovery No abscess No associated ventricular dilation: benign raised intracranial tension. 85 Pathophysiology: Symonds: decreased absorption of CSF secondary to blockage of arachnoid villi Sahs and Joynt: secondary to brain edema Weed and Flexner: disruption in venous circulation as a cause . 86 87 Symptoms : Headache Drowsiness Vomiting Blurring of vision Diplopia Signs: Papilledema 6th cranial nerve palsy Optic disc atrophy 88 Diagnosis : ↑CSF pressure Normal CSF biochemistry MRI is the modality of choice Management: Lowering of the elevated intracranial pressure Medical therapy: Corticosteroids Mannitol Diuretics Acetazolamide Eradication of ear disease 89 In CSOM ostietis and subsequent bone erosion likely expose the nerve to infection This results in inflammation and ultimately facial nerve compression The tympanic segment is the most common area of involvement HRCT of the temporal bone Management : Intravenous antibiotics Prompt surgical intervention: Any attached granulation to the nerve should not be removed Healthy bone should be removed from the nerve on either side of the diseased segment. Concomitant corticosteroids 90 It has two clinically distinguishable subtypes: Localised, circumscribed, or serous labyrinthitis without total or permanent loss of function Diffuse, purulent or suppurative labyrinthitis with permanent total destruction of the sensory elements within the labyrinth 91 As the result of osteitis of the labyrinth capsule or of extension along preformed pathways Potential pathway include: oval window Round window membrane Cholesteatomatous fistula 92 Clinical features: Symptoms Vestibular symptoms precede cochlear symptoms by hours to days when the site of invasion is semicircular canal Profound vertigo Nausea Vomiting Signs: Spontaneous nystagmus towards the unaffected ear. Some degree of ataxia with pastpointing High frequency sensorineural hearing loss Distortion of hearing. 93 Treatment : Parenteral antibiotics 94 Usually following the serous labyrinthitis Involvement of labyrinth secondary to generalized meningitis Symptoms: same as serous labyrinthitis including the lack of fever Key differences: Symptoms are more rapid and intense The onset of severe vestibular symptoms is accompanied by a complete loss of cochleovestibular response A caloric response is conspicuously absent from the disease ear. d/d: cerebellar abscess 95 Treatment: Close and continuous monitoring for symptoms of intracranial extension Bed rest with minimal head movements Antiemetics Antibiotics If meningeal signs are noted: LP Any signs of intracranial spread: labyrinthectomy Premature surgical trauma can promote dissemination of infection: mastoid exploration to be deferred until acute symptoms subside. 96 Bone erosion by cholesteatoma Most common site: dome of the lateral semicircular canal. Symptoms : Episodic vertigo Signs: Fistula test Negative test does not rule out fistula Tullio’s phenomenon Site of fistula: The dome of the LSCC: deviation of eyes towards normal ear. LSCC fistula anterior to the ampulla: deviation towards the affected ear. Erosion of the vestibule: rotatory horizontal deviation towards the diseased ear. SSCC: rotatory movements towards the normal ear PSCC: vertical deviation of the eyes. 97 Investigations: HRCT temporal bone Treatment: Surgery : Managed according to the site, size and status of hearing The rate of total hearing loss is 8% to 56% 98 It is the infected petrosal cells with inadequate drainage causing bone changes of coalescence in the cell walls and resulting in symptoms referable to the petrosa. Symptoms: Gradneigo’s syndrome: 1.Deep-boring pain: depending upon the site of involvement: Posterior group of cells: Anterior petrositis: occipital, parietal, or temporal Discharge is from the mastoid Frontal or behind the eye Drainage is from the tympanum 2.Aural drainage 3,Diplopia : 6th cranial nerve palsy occurs when the apex is involved 99 Investigations: HRCT temporal bone Gallium 67 scan Technetium 99m scan Management : Parenteral antibiotics Surgical drainage 100 Can occur with: Long standing perforation Cholesteatoma Once any type of mastoiditis causes continuous purulent drainage for 8 or more weeks, the likelihood of complete resolution with antibiotics significantly decreases. Hallmark triad: Otalgia Postauricular pain Fever Signs: Postauricular tenderness Protrusion of pinna Postauricular erythema Induration over the mastoid: impending subperiosteal abscess. 101 Investigaton : HRCT temporal bone Treatment : Parenteral antibiotics Mastoidectomy: Significant bony destruction Poor response to up to 2 weeks of conservative management. 102 Direct destruction of cortical bone / hematogenous spread through small vascular channels. Well pneumatized mastoids are more susceptible The most common site of cortex breakdown is through the thin trabecular bone Macewen’s triangle Signs and symptoms: Auricle is displaced forward and outward Fluctuant mass can be palpated behind the ear Bezold’s abscess Luc’s abscess 103 Investigations: HRCT temporal bone Management: Simple mastoidectomy Antibiotics 104 Benzold abscess: Breach in the bony plate forming the inner surface of mastoid tip. Erosion of inner or outer cortex of the mastoid if periphlebitis or phlebitis propagate the infection. Pus track below the sternocleidomastoid or even the layer of cervical fascia. d/d : inflamed lymph nodes Investigation : CT scan Treatment : Complete excision of mastoid pathology Drainage of the abscess Removal of associated granulation tissue. 105 106