Endoscopic-Assisted Canal Wall-up Tympanomastoidectomy for Reduction of Residual Cholesteatoma

Introduction The treatment of cholesteatoma is generally surgical, and the major obstacle is the high prevalence of recidivism. The endoscopic ear surgery technique is proposed to minimize this problem. Objectives To utilize endoscopes to visualize and manipulate cholesteatoma residues after microscopic removal Methods Cross-sectional study. Thirty-two patients with cholesteatoma underwent microscopic wall-up mastoidectomy combined with the endoscopic approach. The subjects were assessed for the presence and location of covert disease. Results Of the 32 cases, 17 (53.12%) had residual cholesteatoma in the endoscopic phase. Minimal disease was found, usually fragments of the cholesteatoma matrix. Pars tensa cholesteatomas had more covert disease than pars flaccida cholesteatomas (62.50% vs 43.75%). Posterior recesses (47.05%) and tegmen tympani (41.17%) were the locations with more covert disease (p < 0.05). Conclusion Cholesteatomas of the pars tensa presented more residual disease and were significantly more common in the posterior recesses and tegmen tympani.

Petrosal Anatomy of the Paleocene Eutherian Mammal Deltatherium fundaminis (Cope, 1881)

We describe the tympanic anatomy of the petrosal of Deltatherium fundaminis, an enigmatic Paleocene mammal based on cranial specimens recovered from New Mexico, U.S.A. Although the ear region of Deltatherium has previously been described, there has not been a comprehensive, well-illustrated contribution using current anatomical terminology. The dental and cranial anatomy of Deltatherium is a chimera, with morphological similarities to both ‘condylarth’ and ‘cimolestan’ taxa. As such, the phylogenetic relationships of this taxon have remained elusive since its discovery, and it has variably been associated with Arctocyonidae, Pantodonta and Tillodontia. The petrosal of Deltatherium is anteriorly bordered by an open space comprising a contiguous carotid opening and pyriform fenestra. The promontorium features both a small rostral tympanic process and small epitympanic wing but lacks well-marked sulci. A large ventral facing external aperture of the canaliculus cochleae is present and bordered posteriorly by a well-developed caudal tympanic process. The hiatus Fallopii opens on the ventral surface of the petrosal. The tegmen tympani is mediolaterally broad and anteriorly expanded, and its anterior margin is perforated by a foramen for the ramus superior of the stapedial artery. The tympanohyal is small but approximates the caudal tympanic process to nearly enclose the stylomastoid notch. The mastoid is widely exposed on the basicranium and bears an enlarged mastoid process, separate from the paraoccipital process. These new observations provide novel anatomical data corroborating previous hypotheses regarding the plesiomorphic eutherian condition but also reveal subtle differences among Paleocene eutherians that have the potential to help inform the phylogeny of Deltatherium.

Middle Fossa Encephaloceles Treated via the Transmastoid Approach: A Case Series and Review of the Literature

BACKGROUND Middle fossa (MF) encephaloceles are rare lesions resulting from herniation through defects in the tegmen tympani or mastoideum. Underlying etiologies and clinical presentations are variable. Surgical goals include fistula obliteration, resection of nonfunctioning parenchyma, and dehiscence repair. The middle cranial fossa approach (MCFA), transmastoid approach (TMA), and combined (MCFA + TMA) approaches have been described. The minimally invasive TMA provides excellent exposure of the pathology and allows for ample working room to repair the defect. OBJECTIVE We present short-term follow-up results in patients treated via the TM repair at our institution. METHODS A retrospective review of patients with symptomatic encephaloceles treated via the TMA by our multidisciplinary team. Patient demographics, clinical presentations, intraoperative findings, repair technique, and outcomes were highlighted. RESULTS A total of 16 encephaloceles in 13 patients were treated. Defect etiologies included spontaneous (50.0%), secondary to chronic infection (25.0%), or cholesteatoma (18.8%). Defects were most often within the tegmen mastoideum (68.8%). Average length of surgery was 3.3 h (95% CI: 2.86-3.67) and length of stay 3.9 d (95% CI: 3.09-4.79). On short-term follow-up (average 11.5 mo), no patients experienced postoperative cerebrospinal fluid leak or recurrence. The majority of patients (83.3%) experienced confirmed improvement or stabilization of hearing. CONCLUSION MF encephaloceles present with various clinical manifestations and result from multiple underlying etiologies. The TMA is an alternative to craniotomy and our short-term results suggest that this approach may be utilized effectively in appropriately selected cases.

Clinicoradiological correlation between preoperative high-resolution computed tomography findings and intraoperative findings in chronic otitis media (squamous type)

<p class="abstract"><strong>Background:</strong> Chronic otitis media is a major health problem with significant morbidity. High-resolution computed tomography (HRCT) is extremely useful for middle ear pathology and extension of the disease. The objective was to study the correlation between preoperative HRCT and intraoperative findings in chronic suppurative otitis media (squamous type).</p><p class="abstract"><strong>Methods:</strong> This analytical study included 61 cases of chronic otitis media (squamous type). Preoperative HRCT findings were correlated with intraoperative findings. Sensitivity, specificity, PPV, NPV and kappa value were estimated.</p><p class="abstract"><strong>Results:</strong> Out of 61 cases 32 were males and 29 were females. Presence of cholesteatoma found on HRCT with 80% sensitivity with k value 0.83 suggesting very good agreement. About ossicular status k value of incus, malleus and stapes were 0.76, 0.65 and 0.54 respectively with sensitivity of 91%, 85% and 58% respectively. Other critical areas on HRCT like sigmoid sinus plate erosion, tegmen tympani dehiscence, scutum erosion, lateral semicircular canal erosion, facial canal erosion and jugular bulb were seen with k value was about 1, 0.8, 0.9, 0.82, 0.72 and 0.65 respectively. So, HRCT shows perfect radiosurgical agreement for sinus plate erosion, very good agreement for disease extension, incus erosion, tegmen tympani erosion, scutum erosion and LSCC erosion and fair agreement for malleus erosion, facial canal erosion and jugular bulb dehiscence and poor agreement for stapes erosion.</p><p class="abstract"><strong>Conclusions:</strong> HRCT is a reliable preoperative investigation in cases of chronic otitis media, squamosal type which would provide a bird’s eye view in the disease process in the ear.</p>

Dural Contact to the Malleus Head in Patients with Superior Semicircular Canal Dehiscence (SSCD): Case Series and Review of SSCD and Tegmen Defects

Objective: Report a series of cases in which patients have concomitant superior semicircular canal dehiscence (SSCD) and a dehiscent tegmen tympani with Dural contact to the malleus head (DCMH). Methods: An analysis of radiologic and audiologic data in 4 patients who presented with SSCD and DCMH at a tertiary care institution. A pertinent literature review was performed. Results: Four patients (5 ears) had SSCD and DCMH. In 3 patients with unilateral DCMH, the mean maximum air-bone gap was 15 dB in the ear with DCMH compared to 50 dB in the ear without DCMH. Of the 5 ears with DCMH, the mean air conduction threshold at 250 Hz was 17 dB compared to 42 dB in the 3 ears without DCMH. Conclusions: We report the findings of DCMH in a series of 4 patients with bilateral SSCD. This limited series suggests that ears with SSCD and DCMH have less of an air-bone gap than would be expected, as 1 would expect an additive effect of DCMH and SSCD on the air-bone gap.

Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Middle Fossa Approaches and Anterior Petrosectomy, Surgical Principles, and Illustrative Cases

Introduction The middle fossa (MF) approaches encompass a group of versatile surgical accesses to pathologies in the MF, internal auditory canal (IAC), and superomedial aspect of the posterior fossa. Although many descriptions of the MF approaches have been published, a practical surgical guide that allows an easy understanding for Skull Base trainees is needed. Methods Three formalin-fixed, colored-injected specimens were dissected under microscopic magnification (six sides). A MF craniotomy followed by IAC drilling was performed on three sides, and anterior petrosectomy (AP) was performed in the remaining three sides. The anatomical dissection was documented in stepwise three-dimensional photographic images. Following dissection, representative case applications were reviewed. Results The MF approach provides direct access to the MF structures and IAC. The AP provides excellent access to the superomedial aspect of the posterior fossa. Key common steps include: positioning and skin incision; scalp and muscle flaps; burr holes; craniotomy flap elevation; dural dissection along the petrous ridge; division of the middle meningeal artery; and exposure of the greater superficial petrosal nerve, tegmen tympani, and V3. Then, to approach the IAC: superior IAC drilling, and longitudinal dura opening. The area drilled in the AP approach forms a pentagon limited by the petrous internal carotid artery, cochlea, IAC, petrous ridge, and lateral border of V3. Conclusion The MF approaches are challenging. Operatively oriented skull base dissections provide a crucial foundation for learning these techniques. We describe comprehensive step-by-step approaches intended to develop familiarity in the cadaver laboratory and facilitate understanding of their potential for skull base disorders. Basic surgical principles are described to help in the operating room as well as illustrative cases.

Concurrent chemoradiation in locally advanced primary middle ear lymphoepithelial carcinoma: an effective treatment modality case report

Background Definitive treatment of primary middle ear lymphoepithelial carcinoma (LEC) is not well established owing to the rarity of this disease entity. We report a case of locally advanced primary middle ear LEC treated with concurrent chemoradiation, with good oncologic outcomes. Case presentation A 46 year-old female of Cantonese (Southern Chinese) descent presented with a four-month history of left sided hearing loss and non-pulsatile tinnitus, associated with progressive ipsilateral facial weakness. She had a left facial palsy (House-Brackmann 2) which then deteriorated to complete palsy over 2 weeks. Otoscopic examination of the left ear revealed a red-hued mass replacing the tympanic membrane. There was no cervical lymphadenopathy. Fibreoptic nasoendoscopy was unremarkable. Pure tone audiometry revealed profound mixed left hearing loss with type B impedance. Computed tomography of the temporal bone showed an ill-defined left middle ear mass with erosion of the malleus, tegmen tympani and facial canal. Magnetic Resonance Imaging showed an avidly enhancing lesion involving the dura of the left middle cranial fossa, tympanic and labyrinthine portions of the facial nerve. This mass extended into the apex of the left internal acoustic canal and basal turn of the cochlea. Histopathology confirmed EBV-positive primary middle ear LEC. Concurrent chemoradiation comprising 70Gy of intensity-modulated radiation therapy and 3 cycles of concurrent Cisplatin based chemotherapy over a 6 week period was administered. The patient achieved near-complete disease resolution on 3 month post-treatment imaging. Serum EBV DNA titres declined to undetectable levels and the patient is disease-free at 18 months post-diagnosis. Discussion and conclusion Concurrent chemoradiation with curative intent may be a viable treatment option for locally advanced middle ear LEC not amenable to surgical resection due to expected surgical morbidity. It confers good oncologic outcomes that mimic the response in other head and neck EBV-related lymphoepithelial carcinomas.