Posterior Mesotympanum Research Articles

Management of a Posterior Mesotympanic Cholesteatoma using the Transcanal Endoscopic Approach

With the constant evolution in the role of endoscopy in middle ear surgery, this article presents a technical note on the transcanal endoscopic approach to resection of a cholesteatoma limited to the posterior mesotympanum. We believe that this technique provides a suitable, minimal-invasive alternative to the classic microscopic transmastoid approach.

A Rare Cause of Conductive Hearing Loss, the Middle Ear Osteoma

Osteomas are benign and frequent bone tumors. Temporal bone osteomas are usually located to the external auditory canal, their location at the middle ear is rare. They are usually revealed by progressive hearing loss. We report the case of a 40-year-old woman who had a right ear conductive hearing loss. A CT-scan showed a bone-density tumor in the right antrum and posterior mesotympanum, hanging up to the tegmen tympani. The diagnosis of middle ear osteoma had been confirmed histologically after a surgical exploration. Middle ear osteomas are rare benign tumors, less than 36 cases was described from 1964. They always present with a hearing loss, and the diagnosis is made by CT-scan. The treatment is usually surgical for symptomatic patients.

Symptom: Conductive Hearing Loss after Cholesteatoma Surgery

Symptom: Conductive Hearing Loss after Cholesteatoma Surgery

Clinical Characteristics of Patients with Cochlear Fistulas Caused by Chronic Otitis Media with Cholesteatoma.

To analyze the clinical characteristics of cochlear fistulas (CFs) and propose a new fistula classification system with regard to the cochlea. A retrospective chart review was conducted between January 2008 and December 2015 to identify patients who had undergone surgery for cholesteatoma with an associated CF. The following data were collected: preoperative symptoms, findings of temporal bone computed tomography (TBCT), fistula stage, cholesteatoma classification, surgical technique, and pre- and postoperative pure-tone audiometry. We analyzed a total of 159 patients, out of which 9 (5.7%) were diagnosed with a CF. The average duration of the chronic otitis media was 19.8 years. Cholesteatomas that induced CF rarely existed in the nonaggressive state; recurrent otorrhea was observed in all but one of our subjects. All the patients with CF had a distinct origin of cholesteatoma that developed from the retraction of posterior pars tensa; further, 88.9% cholesteatomas extended to and filled the sinus tympani. Preoperative audiometry revealed total hearing loss in 4 (44.4%) patients. Further, five patients with residual hearing before surgery had stage I fistulas, and the bone conduction thresholds remained stable after surgery. Cochlear fistulas were often detected in patients with (1) a history of chronic otitis media (exceeding 10 years), (2) frequently recurring otorrhea, and (3) pars tensa cholesteatomas that extended to the posterior mesotympanum and filled the sinus tympani. Such patients can suffer from potentially severe and irreparable sensorineural hearing loss.

Transcanal Endoscopic Ear Surgery for Middle Ear Cholesteatoma.

To evaluate the clinical parameters, outcomes, and complications of transcanal endoscopic ear surgeries for middle ear cholesteatoma. Retrospective study. Tertiary university-affiliated medical center. Adult patients (age >18) who underwent transcanal endoscopic ear surgeries for cholesteatoma, between March 2009 and March 2015. Transcanal endoscopic surgery was indicated when the cholesteatoma did not extend posterior to the anterior limb of the lateral semicircular canal. Rigid endoscopes 4 and 2.7 mm in diameter, 0, 30, 45, and 70 degrees were used with angled picks, suction, and forceps.Preoperative assessment included high-resolution computed tomography of the temporal bones and/or non echo-planar diffusion-weighted magnetic resonance imaging and pure-tone audiometry. Residual or recurrent disease was diagnosed by clinical examination and/or magnetic resonance imaging findings consistent with cholesteatoma. Intra- and postoperative complications, pre- and postoperative audiometric results were recorded. Sixty operations (56 patients, mean age = 43.6) were included.Six operations (10%) were performed under local anesthesia. The most common sites of cholesteatoma involvement were: posterior epitympanum (n = 51, 91%), anterior epitympanum (n = 19, 33.9%), posterior mesotympanum (n = 13, 23.2%), and sinus tympani (n = 11, 19.6%). Intraoperative ossicular chain reconstruction was performed in 18 (30%) cases.Our overall residual and recurrence rates were 10% (n = 6) and 8.3% (n = 5), respectively, with mean duration of follow up of 35 months. The most common sites of residual disease were the mastoid cavity/antrum (n = 3, 50%), tympanic cavity, and posterior mesotympanum. Overall minor and major complication rates were 16.6 and 6%, respectively. Transcanal endoscopic ear surgery was found to be an acceptable and safe technique for the exposure and eradication of middle ear and/or attic cholesteatoma.

Case report of congenital cholesteatoma in the oval window and posterior mesotympanum surrounding a dehiscent fallopian canal in a young adult

Congenital cholesteatoma is defined as cholesteatoma occurring behind an intact tympanic membrane (TM). In the middle ear, it has different stages according to its site and relation with surrounding structures. We report an unusual case which is congenital cholesteatoma in the oval window and posterior mesotympanum surrounding a dehiscent fallopian canal in a young adult without obvious lesion behind intact TM, discussing its management. We have focused light in an unusual case in our practice and concluded that early intervention in such cases is recommended to prevent complications and planning a staged surgery is the treatment of choice.

English

INTRODUCTION: The surgical treatment of cholesteatoma in paediatric age group has changed opinion many times in the evolution of cholesteatoma surgery. Intact canal wall technique allows provision for maintaining the depth of the middle ear and postoperative hearing is much better than in canal wall down procedure. Canal wall down method precludes regular cleaning of the large cavity left behind. In CWU method incidence of recurrent and residual CH are more than in CWD methods. It is more common because inspection of epi-tympanum and medial aspects of the ossicles is not possible in ICW procedures. As a result, the disease recurs within 6 to 12 months. MATERIALS AND METHODS: Fifty children attending the OPD of Government General Hospital Kurnool with CH, confirmed with CT scan are taken and subjected to ICW tympano-mastoidectomy with or without ossiculoplasty. They are followed for a period of 18 months for residual disease,auditory evaluation and otoscopic examination for graft take up. RESULTS: There was improvement in hearing in 78% of the patients. Graft healing was good in 80.85% of cases. Recurrence was seen in 19.15% of patients. 14% of the patients ICW had to be converted to a CWD procedure within 8 months. There were no reports of intra cranial complication in this series. CONCLUSION: ICW procedure in paediatric cholesteatoma gives better results if the disease is limited to the posterior mesotympanum and not beyond the auditus. Uneventful 18months follow up period was seen in 80.85% of the patients. Recurrent disease is less common if the mastoids are less pneumatized. Revision to CWD may be required in early recurrence; in this series it was 14% of the patients.

Middle Ear Gentamicin-Soaked Pledgets in the Treatment of Ménière’s Disease

Assess the relative efficacy and results of the round window hyaluronic acid pledget depot method for intratympanic gentamicin delivery in Ménière's disease. Retrospective case review. Tertiary referral hospital. Prospective symptomatic and audiologic data were collected on 28 patients undergoing intratympanic gentamicin therapy for Ménière's disease refractory to medical treatment between 2003 and 2009. All patients had the round window membrane exposed via a tympanomeatal flap, and any adhesions were removed. Hyaluronic acid pledgets soaked in 40 mg/ml of gentamicin were then packed into the round window niche and posterior mesotympanum, and the tympanomeatal flap was replaced. Patients audiologic and vertigo symptom outcome scores were recorded at follow-up according to the AAO-HNS 1995 guidelines for reporting results in Ménière's disease. Complete or substantial improvement in vertigo (class A or B) was achieved in 88.5% (23/26) of patients. Hearing loss, defined as greater than 10 dB (PTA average at 0.5, 1, 2, and 4 kHz) was noted in 12 (50%) of 24 patients including 4 patients who had developed "dead ears" (16%). The average hearing loss for all patients excluding the 4 patients with dead ears was 10.7 dB. Round window hyaluronic acid pledget technique used as a sustained delivery vehicle for intratympanic gentamicin treatment for Ménière's disease produces similar rates of vertigo control compared with other techniques but a greater risk of hearing loss. We would recommend the intratympanicinjection titration technique as first line for most patients.

Anatomic Limitations of Posterior Tympanotomy

To radiologically evaluate the anatomic factors that may determine the view field or the accessibility of the posterior tympanotomy into the posterior mesotympanum, a cohort of 30 patients with pneumatic mastoids and 30 patients with unilateral sclerotic mastoids were included. Anatomic relationships were evaluated according to 5 parameters. The reference parameter of the view field through posterior tympanotomy was the maximum view to the stapes area through posterior tympanotomy. Direct distance between the chorda tympani nerve and the facial nerve (FN) and angle between the cortex of the external auditory canal and the FN showed significant positive correlations in pneumatic and sclerotic mastoids. However, the location of the FN was negatively correlated with the maximum view to the stapes area through posterior tympanotomy only in pneumatic mastoids. In particular, the angle between the cortex of the external auditory canal and the FN showed the best correlation with the maximum view to the stapes area through posterior tympanotomy. The angle between the cortex of the external auditory canal and the FN was the most important anatomic determinant for visibility through posterior tympanotomy. This study suggests that pneumatic mastoids, but not sclerotic mastoids, may have a more complex relationship including more factors than those considered in this study. Although this study was performed radiologically, this study can present the insight to surgeons or radiologists.

Congenital Middle Ear Cholesteatoma

Background and Objectives:Congenital middle ear cholesteatoma (CMEC is a keratinous mass behind an intact tympanic membrane. CMEC does not have a history of instrumentation and is less common than acquired one. Many theories have been put forward to explain the pathophysiology of CMEC, however, none of these so far have been convincingly proven. This clinical study was performed to investigate the characteristic features of CMEC and to evaluate the correlation between pathophysiology and CMEC by retrospectivly reviewing the cases. Materials and Method:The medical records of patients who underwent otologic procedures at the hospitals of the Catholic university from January 1993 to September 1998 have been reviewed. They were ten males and four females, ranging in age from 4 to 59 (mean age 18. Results:Three of the 14 patients had the lesions isolated to the anterosuperior quadrant of the mesotympanum which were cystic, easily removed and did not affect hearing. The others had more serious condition with extension into the posterior mesotympanum, which were large, often too extensive to indicate a formative site, and causing ossicular damage. Conclusion:CMEC presents in two distinctive forms according to the site of formation;the anterosuperior and posterior mesotympanum. The review suggest that the pathophysiology of posterior lesions may be different from anterior ones. For early diagnosis of CMEC, screening program should be carried out in children to prevent the more extensive diseases. (Korean J Otolaryngol 1999;42:570-5

Analysis of axial temporal bone computed tomography scans for performing a safe posterior tympanotomy

A posterior tympanotomy is a procedure performed to access the posterior mesotympanum to remove pathologic lesions through a mastoid exposure. In this study, we aimed to evaluate and classify the anatomical relationships between the vertical segment of the facial nerve and the mastoid antrum in an axial temporal bone CT to prevent facial nerve injury when performing a posterior tympanotomy. We performed retrospective analysis of temporal bone CT scans. A cohort of 102 patients who underwent tympanomastoidectomy for chronic otitis media, and 43 patients with sensorineural hearing loss with normal temporal bone, were included. All patients had preoperative and diagnostic computed tomography of the temporal bone from January to December 2006. Anatomical relationships were evaluated according to several parameters: protrusion of the facial nerve into the mastoid antrum, status of the facial canal, new bone formation over the facial canal, and size of the mastoid antrum. Anatomical relationships between the vertical segment and the mastoid antrum were classified into six types. Type 1 has no protrusion of the facial nerve with a regular facial canal, and Type 2 has no protrusion with a partly thin facial canal. Type 3 has protrusion into the antrum with a regular facial canal, and Type 4 has protrusion with a partly thin facial canal. Type 5 has new bone formation around the facial canal, and Type 6 has new bone formation with a small or contracted antrum. These results may enable preoperative assessment of the facial nerve's status, and provide background knowledge to prevent facial nerve injury when performing a posterior tympanotomy.

The clinical evaluations of pathophysiology for congenital middle ear cholesteatoma

Purpose: Congenital middle ear cholesteatoma (CMEC) is less common than the acquired variety. Many theories have been put forward to explain the pathophysiology of CMEC; however, none of them have been convincingly proven thus far. This clinical study was performed to analyze the case reviews; assess the characteristic features of CMEC, and evaluate the correlation between those features and the pathophysiology of CMEC. Methods: The medical records of patients who underwent otologic procedures at the hospitals of the Catholic University, Seoul, Korea, from January 1993 to November 1998 have been reviewed. Results: Of the 14 patients, 3 had cystic lesions isolated to the anterosuperior quadrant of the mesotympanum. The lesions were easy to remove and did not affect the patients' hearing. Eleven patients had more extensive disease with posterior mesotympanum involvement; the lesions were large, were often too extensive to indicate a formative site, and caused ossicular damage. Conclusion: CMEC manifests in 2 distinctive forms according to the formation site. This distinctive formation site suggests that the pathophysiology of posterior lesions may be different from that of anterior ones. For early diagnosis of CMEC, a screening program should be established for children to prevent more extensive disease. (Am J Otolaryngol 2001;22:184-189. Copyright © 2001 by W.B. Saunders Company)

Aeration and drainage pathways of Prussak's space

Objective: the purpose of this study was to document the aeration and drainage pathways of Prussak's space. Methods: 55 temporal bones with an age range from neonate to 11 years of age were serially sectioned to 20 microns, every 10th section was saved and stained by Hematoxylin eosin. Each consecutive section was studied as to the connections of Prussak's space to adjacent compartments and measurements of the dimensions were made for both Prussak's space and its aeration pathways. Results: the classic aeration pathway via the posterior pouch, as described by Prussak in 1867, was found in 34 ears (62%). In 19 (36%), aeration occurred superior to the posterior pouch in the region of the lower lateral attic and the upper mesotympanum. In these ears the posterior pouch had formed, but its superior limit ended blindly in the tympanic membrane. In two temporal bones the aeration pathway was from the anterior pouch and in these cases also a blind posterior pouch had developed. In one temporal bone an auxiliary pathway in addition to the route via the posterior pouch was through the roof (the lateral malleal ligamental fold) of Prussak's space to the overlying lateral malleal space. The height of the posterior pouch varied with a range from 0.5 to 2.4 mm, and the greatest width, which was towards the posterior tympanic spine, varied from 1.6 to 3.2 mm. The superiorly blind posterior pouch was shorter, ranging from 0.4 to 1.2 mm in height. The most frequent route of the chorda tympani nerve was running from 0.5 to 1 mm medial to the posterior malleal ligament in the anterior half of the pouch, joining it posteriorly, or it was connected to it by a short fold, 37 ears (67%). In 18 cases (33%) the chorda was surrounded by its own fold, thus entirely separate from the posterior malleal ligamental fold during its entire course across the tympanum. Conclusions: we have made a detailed documentation of the aeration and drainage pathways of Prussak's space and the findings concur, with important modifications, with Prussak's original description. There is no evidence for contemporary claims that Prussak's space would be aerated superiorly between the lateral incudal and malleal folds. Prussak's space and its aeration pathway is an unit of its own, entirely separate of the major epitympanic compartments which are aerated via the tympanic isthmus. Due to frequent disease processes in the lower lateral attic and posterior mesotympanum, Prussak's space and its aeration pathway are likely to become blocked. This may lead to obliteration of Prussak's space and to the development of retraction pocket or papillary ingrowth cholesteatoma.

Congenital cholesteatomas of the middle ear: A different experience: Karmarkar S.; Bhatia S.; Khashaba A.; Saleh E.; Russo A.; Sanna M.Am. J. Otol. (ITA) (1996) 17/2 (288–292)

A retrospective analysis is presented of 44 cases of congenital cholesteatoma of the middle ear. Twenty-one patients had cholesteatoma localized to the posterosuperior mesotympanum in complete contrast to the commonly reported anterosuperior location seen in only two cases. The remaining 21 patients had cholesteatoma involving either the entire mesotympanum or epitympanum or both. The posteriorly located congenital cholesteatomas might represent a completely different entity and originate from the trapped epithelial cell rests in the posterior mesotympanum during the development of temporal bone. All but one patient were treated by using a closed tympanoplasty. Eight patients underwent a single-stage surgery. A preplanned second-stage procedure was performed in 33 patients, and three are awaiting their second stage. Residual disease was seen in 19 (57%) patients undergoing second-stage surgery. No patient has had recurrent disease so far. Thirty-eight (85%) patients had a preoperative air-bone gap of > or = 30 dB. Of the 33 patients considered for hearing results, 16 (48%) had a postoperative gap within 10 db.

Retrofacial Approach to the Hypotympanum

Otologic disease often extends into the hypotympanum, posterior mesotympanum, and infralabyrinthine compartments. Surgical access to these areas can be difficult because of the proximity of the facial nerve. In patients with a normal bone anatomy, these regions can be accessed by a retrofacial approach, which spares the posterior canal wall and avoids transposition of the facial nerve. The anatomy of the hypotympanum, posterior mesotympanum, and infralabyrinthine compartments will be reviewed emphasizing gross anatomic documentation. We will detail the surgical approach to these areas along the retrofacial air cell tract, and will present an appropriate case history.

CONGENITAL MIDDLE EAR CHOLESTEATOMA

Forty-three patients with congenital middle ear cholesteatoma have been described since the first case in 1953. In these patients ten cholesteatomas were confined to the anterior mesotympanum in young children who had no ossicular damage. Involvement of the posterior mesotympanum (8 ears), meso and epitympanum (21 ears), and antrum and middle ear (7 ears) was associated with an 81% incidence of ossicular erosion in addition to other abnormalities. Anterior mesotympanic cholesteatomas were readily identified by the appearance of a white mass behind a translucent drum. The other congenital cholesteatomas had a more varied appearance with a mass and a whitish appearance each noted in about half. In almost half there was a bulging of the TM. Two new cases are reported: a 4-year-old with an extensive epi and mesotympanic cholesteatoma initially misdiagnosed as non-suppurative otitis media and a 23-year-old with the third reported case of bilateral congenital cholesteatoma.