Results 1 to 1 of 1

Thread: DISLOCATED INCUS pictures - Ear Atlas

  1. #1

    Default DISLOCATED INCUS pictures - Ear Atlas

    Summary
    A material of 40 patients with diagnosis dislocation of the incus is presented. 37 of these patients had either a history of cranial trauma, or information about previous simple mastoidectomy or paracentesis. The work has two aspects, the first a clinical aim, since we find that an average of 9 years had elapsed from trauma to exploration of the middle ear, a period much too long. The importance of having all patients with head trauma referred to an otologist is stressed.
    The second aspect is patho-anatomical, since we in 92% of the traumatic dislocations find a completely normal or partly unharmed incus. These findings are not quite in accordance with the current conception, that bone destruction and resorption is due to anoxia. The ossicles are deprived of their essential blood supply and yet nearly unharmed.

    Zusammenfassung
    40 Patienten mit Amboß-Luxationen wurden beobachtet. 37 von diesen hatten eutweder ein Schädeltrauma in der Vorgeschichte oder wußten von vorangegangenen Antrotomien oder Parazentesen. Die Veröffent lichung hat zwei Gesichtspunkte: zunächst einen klinischen. Da wir fanden, daß durchsehnittlich ein Zeitverlauf von 9 Jahren zwischen Trauma und ärztlicher Untersuchung des Mittelohres eine viel zu lange Zeitperiode darstellt, wird die Wichtigkeit hervorgehoben, allen Patienten nach Schädeltrauma einem Otologen vorzustellen.
    Der zweite Aspekt ist ein pathologisch-anatomischer, da in 92% der traumatischen Dislokation ein völlig normaler oder nur teilweise beschädigter Amboß gefunden wurde. Dieser Befund stimmt nicht ganz mit der laufenden Meinung überein, daß durch Anoxie eine Destruktion und Resorption des Knochens entsteht. Die Gehörknöchelchen sind von ihrer Haunt-Blutzufuhr abgeschnitten und trotzdem fast unversehrt.

    Introduction
    The middle ear and temporal bone are often involved in accidents involving trauma to the head. Temporal bone fractures can cause numerous sequelae, including facial nerve injury, cerebrospinal fluid otorrhea, vestibular dysfunction, sensorineural hearing loss, and damage to the sound conducting system .
    Ossicular chain dislocation (OCD) is an interruption in the ossicular chain, or any other disorder which may prevent the ossicular chain from vibrating effectively. Ossicular chain dislocation may occur with a temporal bone fracture, traumatic tympanic membrane perforation, or barotrauma. OCD is seen more frequently than ossicular fracture . The most common form of ossicular discontinuity after temporal bone trauma is separation of the joint connecting the incus to the stapes. The second most common is separation of the joint connecting the malleus to the incus .
    This is a report that present a rare case of isolated traumatic dislocation of the incus to the antrum and a simple method for controlled application of incus to the ossicular chain.

    Case report
    A 15-year-old boy was admitted to our department because of left-sided hearing impairment secondary to motor vehicle accident one month after the injury. Otoscopic examination and facial nerve function were normal. The tympanic membranes were normally visualized. The otologic tests had shown moderate conductive-type hearing loss (45 dB) on the left side .
    DISLOCATED INCUS pictures Atlas attachment.php?s=07dde559909cd36ad9948634bc318fd4&attachmentid=1852&d=1441387755

    Discussion
    A large part of all head injuries involves the ear and the temporal bone. The accidents most frequently encountered are those involving motor vehicles; however, industrial and athletic injuries may also present potential lesions in the temporal bone and middle ear. The features and management of such injuries are discussed with special emphasis on the new concepts of damages to the middle and inner ear which sometimes are accessible to medical or surgical treatment .
    The most common form of temporal bone fracture, occurring from blunt trauma, is the longitudinal fracture of the temporal bone. It is estimated that 70% to 90% of temporal bone fractures are longitudinal. Longitudinal fractures of the temporal bone most often cross the tympanic ring, causing a tear in the tympanic membrane, and active bleeding from the middle ear may be observed. Hearing loss associated with temporal bone fractures occurs in 68–96% of injured children, but persists beyond 1 month in only 13%. Transverse temporal bone fractures are associated with sensorineural loss from injury to the cochlea or organ of Corti, and longitudinal temporal bone fractures usually cause conductive hearing loss .
    When the otoscopic examination is found to be normal, an ossicular chain lesion must be suspected. A high-resolution CT- scan with 1 mm contiguous sections is the method of choice for assessing the etiology of a conductive hearing loss .
    Conductive hearing loss may be caused by middle ear hemorrhage or ossicular disruption. The most common cause of injuries to the ossicles of the middle ear is indirect trauma in head injuries. In most patients, middle ear bleeding and attendant hearing loss resolves in weeks. Most cases with injuries of the ossicles show a conductive hearing loss of varying degree. When a perilymphatic fistula is present, there might be a combined fluctuating hearing loss and the patient may have transient vestibular symptoms such as positional vertigo or dizziness, especially in Valsalva’s maneuver .
    The most common ossicular dislocation is separation of the incudostapedial joint with or without dislocation of the body of the incus from the articulation with the malleus head. The second most common injury of the ossicular chain is fracture of the stapes crura. This lesion is identified most frequently by the preoperative audiometric evaluation . In a few patients, ossicular injury is the cause of unresolved hearing loss and may require surgical intervention. Reconstruction of the ossicular chain is considered if a patient has a conductive hearing loss of more than 30 dB .
    The treatment of choice when injuries of the ossicles are confirmed or even suspected is surgical exploration of the tympanum, tympanotomy, and reconstruction of the ossicular chain, when required, in order to restore the hearing. This can be done by transposition, autotransplants or introduction of plastic, metallic or ceramic prosthesis depending on the type and extent of the injury . We performed exploratory tympanotomy under general anesthesia via a postaural approach in our case. The incus was removed from antrum and taken out. Incus was re-shaped with microdrill and placed between malleus and stapes.
    This method provided an accurate repair of the OSC and resulted in an anatomically normal articulation as the mass and shape of the ossicles was preserved. Hearing loss is a common complaint after middle and inner ear trauma. Evaluation of hearing should be done with formal audiometry, and high-resolution CT- scan. Conductive hearing loss greater than 40dB have to alert the physician to the possibility of ossicular discontinuity.

    INTRODUCTION
    Cranioencephalic trauma (CET) is one of the leading morbimortality causes in Brazil and in the world, most commonly occurring in the young adult age group

    Most temporal bone fractures result from high-energy blunt head trauma, many times related to other skull fractures or to polytrauma. For such a reason, a multidisci*plinary evaluation is generally required, including otolaryngology, radiology and neurosurgery.

    Multidetector computed tomography plays a fundamental role in the assessment of such patients. According to a study published by Morgado et al., in spite of most CET cases (82.4%) being classified as mild, tomographic changes were observed in approximately 80% of their patients. Such data highlight the importance of skull computed tomography as the method of choice in the initial assessment of such patients, in addition to the Glasgow Coma Scale and information regarding the accident.

    Multiplanar reconstructions allow detailed evaluation of the base of the skull, temporal anatomy as well as the extent of injuries involving specific structures.

    Currently, in addition to representing the imaging study of choice for the diagnosis and prognosis in cases of CET, computed tomography also plays an important role in the follow-up of injuries.

    The relationship between types of injuries demonstrated by computed tomography, types of CET (severity of the injury) and prognosis has been described by several authors in the literature, all of them demonstrating approximately the same relationship: the more severe the CET, the more numerous and more severe are the findings at computed tomography
    DISLOCATED INCUS pictures Atlas attachment.php?s=07dde559909cd36ad9948634bc318fd4&attachmentid=1853&d=1441387774

    Fractures and displacements of the ossicular chain in the middle ear represent one of the main complications of temporal bone injuries, the latter being frequently observed in cases of severe CET, and for that reason, are more deeply approached in the present study.

    The radiologist must be familiar with the possible trauma mechanisms and with the temporal anatomy, allowing the proper classification of fracture types in order to predict possible associated complications and to guide the appropriate treatment.

    IDENTIFICATION OF THE AFFECTED STRUCTURES: INJURIES TO THE OSSICULAR CHAIN
    Ossicular injuries represent a frequent complication from temporal trauma, possibly leading to interruption of different segments of the ossicular chain.

    In cases of patients who suffered temporal trauma, conductive hearing loss is the most common consequence of this type of injury, with dislocations being more frequently observed than ossicular fractures.

    There are five types of dislocations as follows: incudostapedial joint dislocation; malleoincudal joint dislocation; dislocation of the incus; dislocation of the malleoincudal complex; stapediovestibular dislocation
    Fractures of the malleus, incus and stapes are uncommonly observed.

    High resolution computed tomography is the method of choice to evaluate ossicular trauma. Axial images allow a better evaluation of ossicular continuity. Coronal and oblique reconstructions may be used in the evaluation of the long process of the incus as well as its relationship with the malleus, as it can be seen below.

    References:
    Radiologia Brasileira - Temporal bone trauma and complications: computed tomography findings
    Traumatic total incus dislocation from ossicular chain
    Dislocation of the incus - Springer











    Last edited by Medical Photos; 09-04-2015 at 05:29 PM.

  2. Similar Threads

    1. Pictures and Anatomy of the Stapes pictures - Ear Atlas
      By Medical Videos in forum E.N.T Atlas(Photos of cases)
      Replies: 0
      Last Post: 02-28-2009, 09:33 AM
    2. Otosclerosis and Stapedectomy pictures - Ear Atlas
      By Medical Videos in forum E.N.T Atlas(Photos of cases)
      Replies: 0
      Last Post: 02-28-2009, 09:33 AM
    3. Perilunate Dislocation Pictures - Skeletal trauma radiology atlas
      By Medical Videos in forum Anatomy and Orthopedics Atlas(Photos of cases)
      Replies: 0
      Last Post: 02-18-2009, 10:54 AM
    4. Surgical Pictures of Atticotomy- Ear Atlas
      By Medical Videos in forum E.N.T Atlas(Photos of cases)
      Replies: 0
      Last Post: 01-22-2009, 11:42 AM
    5. Pictures and Anatomy of the Malleus - Ear Atlas
      By Medical Videos in forum E.N.T Atlas(Photos of cases)
      Replies: 0
      Last Post: 01-18-2009, 12:11 PM

Tags for this Thread

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
About us
Medical Educational Site for Medical Students and Doctors Contains Free Medical Videos ,Atlases,Books,Drug Index ,Researches ,Health and Medical Technology news.
  • Privacy Policy
  • Join us
    Powered by vBulletin® Version 4.2.0 Copyright © 2015
  • vBulletin®
  • Solutions, Inc. All rights reserved. vBulletin Metro Theme by
  • PixelGoose Studio