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It is important for the ENT surgeon to be familiar with the anatomy of the facial nerve and to prevent iatrogenic injury to nerve as it shows variations in its intratemporal course. Present study was done to delineate the intratemporal course of facial nerve and observe its variations. Thirty wet cadaveric temporal bones were dissected in the temporal bone dissection laboratory in the Department of Otorhinolaryngology and Head Neck Surgery, Government Medical College, Patiala. The length of intratemporal segments of facial nerve, its relationship with important bony landmarks, and the presence of any anomaly or variations in its course were observed. The mean length of labyrinthine, tympanic and mastoid segment was found to be 4.28 ± 0.605 mm, 10.40 ± 1.416 mm and 12.34 ± 0.915 mm respectively in the dissected specimens. The first and second genu angle varied between 50°–90° and 90°–120° respectively. Facial canal dehiscence was present at the level of first genu in 10% of cases and at the level of tympanic segment in 33%. Distance between chorda tympani origin and stylomastoid foramen varied between 4 and 6 mm with mean value of 5.31 ± 0.603 mm. Chorda-facial angle was found to be in the range of 20° to 31° with mean of 25.30° ± 2.90°. The tympanomastoid segment of facial nerve has variations in length and in its relations with various middle ear structures. The facial canal, as it traverses the temporal bone, may display bony dehiscence, variations, and anomalies in its natural course, having its own clinical and surgical significance.

Objectives To correlate the radiological assessment of the mastoid facial canal in postoperative cochlear implant (CI) cone-beam CT (CBCT) and other possible contributing clinical or implant-related factors with postoperative facial nerve stimulation (FNS) occurrence. Methods Two experienced radiologists evaluated retrospectively 215 postoperative post-CI CBCT examinations. The mastoid facial canal diameter, wall thickness, distance between the electrode cable and mastoid facial canal, and facial-chorda tympani angle were assessed. Additionally, the intracochlear position and the insertion angle and depth of electrodes were evaluated. Clinical data were analyzed for postoperative FNS within 1.5-year follow-up, CI type, onset, and causes for hearing loss such as otosclerosis, meningitis, and history of previous ear surgeries. Postoperative FNS was correlated with the measurements and clinical data using logistic regression. Results Within the study population (mean age: 56 ± 18 years), ten patients presented with FNS. The correlations between FNS and facial canal diameter (p = 0.09), wall thickness (p = 0.27), distance to CI cable (p = 0.44), and angle with chorda tympani (p = 0.75) were statistically non-significant. There were statistical significances for previous history of meningitis/encephalitis (p = 0.001), extracochlear-electrode-contacts (p = 0.002), scala-vestibuli position (p = 0.02), younger patients’ age (p = 0.03), lateral-wall-electrode type (p = 0.04), and early/childhood onset hearing loss (p = 0.04). Histories of meningitis/encephalitis and extracochlear-electrode-contacts were included in the first two steps of the multivariate logistic regression. Conclusion The mastoid-facial canal radiological assessment and the positional relationship with the CI electrode provide no predictor of postoperative FNS. Histories of meningitis/encephalitis and extracochlear-electrode-contacts are important risk factors. Key Points • Post-operative radiological assessment of the mastoid facial canal and the positional relationship with the CI electrode provide no predictor of post-cochlear implant facial nerve stimulation. • Radiological detection of extracochlear electrode contacts and the previous clinical history of meningitis/encephalitis are two important risk factors for postoperative facial nerve stimulation in cochlear implant patients. • The presence of scala vestibuli electrode insertion as well as the lateral wall electrode type, the younger patient’s age, and early onset of SNHL can play important role in the prediction of post-cochlear implant facial nerve stimulation.

Background: Stylomastoid foramen is the terminal part of facial canal and is the exit gateway for facial nerve from skull base. We hypothesized that anatomical variations of this foramen could be a risk factor for the injury of facial nerve resulting in unilateral facial nerve paralysis or Bell’s palsy. Hence the present study was conducted to study the variations in size and shape of stylomastoid foramen in dry adult human skulls. Materials and methods: The study was conducted on 37 dry adult human skulls of unknown age and sex. High resolution images of the skulls under study were processed by ImageJ software and observations were undertaken. Results: Total eight variations of stylomastoid foramen were observed in terms of shape. The common variants were round, oval and square (present in 83.79% skulls on right side and 81.07% skulls on left side), whereas the rare variants were triangular, rectangular, serrated, bean-shaped and irregular. It was noted that stylomastoid foramen were associated with extensions (45.95% skulls) and also adjacent foramen (18.92% skulls). Exclusively unilateral observations included bifurcation of foramen (16.22% skulls), foramen situated deep inside skull groove (5.41% skulls) and foramen interrupted by bony spur (2.7% skulls). No significant differences were observed between the mean diameters (antero-posterior and transverse) of the stylomastoid foramen. Conclusions: The unilateral variations along with rare variations in terms of shape such as serrated, bean-shaped and irregular foramen (which were also unilateral findings) could be potential risk factors towards injury of facial nerve at the point of exit from skull base leading to Bell’s palsy.

BACKGROUND AND PURPOSE: Cone-beam CT is being increasingly used in head and neck imaging. We compared cone-beam CT with multidetector CT to assess postoperative implant placement and delineate finer anatomic structures, image quality, and radiation dose used. MATERIALS AND METHODS: This retrospective multicenter study included 51 patients with cochlear implants and postoperative imaging via temporal bone cone-beam CT (n = 32 ears) or multidetector CT (n = 19 ears) between 2012 and 2017. We evaluated the visualization quality of single electrode contacts, the scalar position of the electrodes, cochlear walls, mastoid facial canal, metallic artifacts (using a 4-level visual score), and the ability to measure the insertion angle of the electrodes. The signal-to-noise ratio and radiation dose were also evaluated. RESULTS: Cone-beam CT was more sensitive for visualizing the scalar position of the electrodes (P = .046), cochlear outer wall (P = .001), single electrode contacts (P .99), and mastoid facial canal wall (P = .07) and the ability to measure the insertion angle of the electrodes (P > .99). The conebeam CT group had significantly lower dose-length product (P

Objectives To evaluate the incidence of facial canal dehiscence (FCD) and other intraoperative findings over the last 20 years as well as correlation with the Japanese Otological Society/European Academy of Otology and Neurotology classification in patients with cholesteatoma. Materials and methods A total of 469 patients operated from 1998 to 2018 were selected and divided into 2 groups of 10 years each. Results Dehiscence was significantly higher in patients with a history of pathology longer than 5 years (22.7%). Higher values were observed in revision surgery, 44.4% in the first period and 41.7% in the second. The tympanic segment was the one most frequently involved, affecting 92% of patients in the first period and 97% of patients in the second. Dehiscence occurred significantly more often in patients with a semicircular canal fistula, 14.8% in the first decade and 8.8% in the second. The incidence of FCD was significantly higher in patients with primary cholesteatoma (especially in those with combined pars tensa-flaccida) than in those with a secondary acquired one, 31.5% vs 7.4% in the first period, 21.1% vs 7.4% in the second, and in those with a stage III disease, 42% in the first period, 33.3% in the second. Conclusion Patients with a shorter history of cholesteatoma as well as those not previously operated had a lower incidence of FCD. The tympanic tract of the facial nerve remains the most frequent site of dehiscence, while the association between dehiscence and fistula of the semicircular canal remains strong. Patients with combined pars tensa-pars flaccida and stage III cholesteatoma have a higher incidence of FCD.

Objective Some cases of peripheral facial paralysis are resistant to treatment, thus, a non-recovery model of facial paralysis is needed to develop new treatment strategies for this condition. The purpose of the current study was to develop an animal model of which facial palsy was severe and prolonged. Methods Ten 8-week-old female Hartley guinea pigs weighing between 400 and 500 g were used for the animal model. The vertical segment of the facial canal was accessed via the otic bulla, without removing the bony wall of the facial canal. The canal was then frozen for 5 s using freeze spray. Facial movements, electroneurography (ENoG), histology, and changes in temperature were evaluated. Results All animals exhibited complete facial paralysis immediately after the procedure and recovered gradually, however, not all of them had recovered completely 15 weeks after freezing. The ENoG values one week after freezing for all animals (10/10) were 0%. Histological examination one week after freezing revealed that most of the vertically placed myelinated nerve fibers which had been frozen were remarkably affected and denatured. The number of vertically placed myelinated nerve fibers increased 15 weeks after freezing, but the nerve fibers were smaller than normal nerve fibers and were distorted in shape. Conclusion Complete facial paralysis was induced in Hartley guinea pigs by freezing the facial canal. The behavioral, ENoG, and histopathological data suggest that the facial paralysis was severe and prolonged. This model may assist in developing novel treatment for severe facial palsy and facilitate basic research on facial nerve regeneration.

Objective Avoidance of iatrogenic injury to the facial nerve is crucial during ear surgery. The anatomical relationship between the tympanic portion of the facial canal (FC) and the mastoid portion of the facial nerve was analyzed using multi-slice computed tomography (CT) scans to avoid iatrogenic facial nerve injury. Methods In total, 364 ears of 351 patients who underwent CT scans were enrolled. The 364 ears were divided into two groups: 281 ears with middle ear inflammation (MEI) and 83 ears without middle ear inflammation (non-MEI). The anatomical relationship between the tympanic portion of the FC and mastoid portion of the facial nerve was analyzed on multi-slice CT images. The ears were categorized into three subgroups based on the course of the mastoid portion of the facial nerve to the tympanic portion of the FC: (“lateral running course”, LRC), “on the tympanic line course” (OL), and “medial running course” (MRC). The proportions of ears in each subgroup were compared between the MEI and non-MEI groups. Results Overall, 15% of ears were categorized as LRC, 30% were OL, and 55% were MRC. In the MEI group, the proportions of LRC, OL, and MRC ears were 17%, 32%, and 51%, respectively, whereas they were 7%, 24%, and 69% in the non-MEI group. The proportion of LRC ears in the MEI group was significantly higher than that in the non-MEI group. Conclusions Especially in patients with MEI, a more LRC for the facial nerve increases the risk of facial nerve injury during posterior tympanotomy or canal wall down mastoidectomy. The course of the facial nerve in the temporal bone should be evaluated before surgery on multi-slice CT images.

Introduction Chronic otitis media squamous is a gradually expanding destructive lesion and leads to complications by eroding the adjacent structures. Facial canal and ossicles are in close proximity in the middle ear space and they share the same pathogenesis of the bony erosion. Ossicular chain erosion found intraoperatively due to cholesteatoma, may suggest the likelihood of facial canal dehiscence. This study was conducted to assess the relationship between ossicular chain erosion and facial canal dehiscence in chronic otitis media squamous. MethodsIt is a retrospective chart review of patients who had mastoidectomy done for chronic otitis media squamous in Tribhuvan University Teaching Hospital from January 2014 to December 2018. The operative findings of facial canal dehiscence were correlated with ossicular chain status. ResultsAmong 158 cases, facial canal dehiscence was seen in 20 (12.7%), of which, 19/20 (95%) had ossicular erosion. Majority (90%) of dehiscence was in the horizontal segment. Incus was the most common ossicle to be eroded. Among the ossicles, stapes erosion was related to the facial canal dehiscence with odds ratio of 3.216 (1.235-8.374) and p-value 0.03. ConclusionAmong the ossicles, there is a relationship between the stapes erosion and the facial canal dehiscence in chronic otitis squamous. Erosion of ossicular chain especially stapes should alert surgeons towards the possibility of facial canal dehiscence.

Temporal bone trauma is frequently encountered in the emergency department. Technologic advances have enabled timely acquisition of thin-section images and multiplanar reconstructions such that temporal bone anatomy can be evaluated in great detail, with excellent delineation of fractures. The temporal bone is composed of a myriad of tiny structures, including many fissures and canals, that must be distinguished from true fractures. In addition, injury to important structures may result in serious complications such as hearing loss, dizziness, imbalance, perilymphatic fistula, cerebrospinal fluid leakage, facial nerve paralysis, and vascular injury. Structures that should be examined include the tympanic cavity and tegmen, the ossicular chain, the bony labyrinth, the facial canal, the internal carotid artery, the jugular foramen and venous sinuses, and the intracranial contents. Radiologists should be familiar with the anatomy of the temporal bone and be able to describe any pathologic findings and make suggestions to referring clinicians to guide management and determine the prognosis. The authors describe the typical CT and MRI appearances of temporal bone trauma, entities that mimic this injury and thus must be differentiated, and compulsory points for evaluating clinically relevant associated complications. Instruction is provided for acquiring the diagnostic skills necessary to report suggested injury status, complications, and likely sequelae to clinicians.©RSNA, 2020.

Background: Unsafe or atticoantral chronic suppurative otitis media (CSOM) is characterized by scanty, purulent, and foul-smelling discharge with attic or marginal tympanic membrane perforation. This can be associated with serious complications. Objective: The objective of the study was to evaluate the pre-operative high-resolution computed tomography (HRCT) temporal bone findings in unsafe CSOM and to determine its usefulness in patients undergoing surgery. Materials and Methods: In this prospective study, 50 random patients with clinically diagnosed as unsafe CSOM from the ENT Department were subjected to HRCT temporal bone in the Department of Radiodiagnosis, Sriram Chandra Bhanj Medical College, Cuttack. The radiological findings were compared with the intraoperative findings. Results: The study results show a good correlation between the pre-operative (HRCT) and intraoperative findings. Cholesteatoma was seen in 35 cases. Ossicle erosion was seen in 40 cases with incus being the most commonly eroded ossicle, followed by scutum erosion (25 cases), mastoid cortex erosion (10 cases), sinus plate erosion (8 cases), tegmen erosion (6 cases), lateral semicircular canal erosion (4 cases), and facial canal erosion (5 cases). Among the extracranial complications (32 cases), mastoiditis was the most common complication and among the intracranial complications (3 cases), epidural abscess was most commonly seen. Conclusion: HRCT temporal bone helps in depicting the site, extent of the disease, bony erosions, and complications associated with the disease proving to be very helpful in surgical planning. Hence, it is necessary to preoperatively evaluate every case of unsafe CSOM with HRCT.

High resolution computed tomography (HRCT) of temporal bone helps in understanding the complex anatomy of temporal bone and in identifying disease in temporal bone. However, its role in diagnosing cholesteatoma and analyzing its extent and complications is not established unequivocally. Present study was undertaken to check sensitivity and specificity of HRCT in diagnosing cholesteatoma and assessing its extent and in identifying ossicular destruction and other complications. In this prospective study in 50 patients with clinical diagnosis of cholesteatoma, preoperative high-resolution temporal bone CT scans axial and coronal view were carried out and compared with intra-operative findings. Kappa statistics was used for radio-surgical correlation. Comparison of CT scan findings with intraoperative findings revealed perfect correlation for sigmoid plate erosion, mastoid cortex dehiscence and scutum erosion, strong correlation for erosion of malleus, posterior superior wall and peri labyrinthine cells, good for erosion of incus and stapes, labyrinthine fistula, tegmen erosion and extent of disease and moderate correlation for facial canal dehiscence. HRCT scan of the temporal bone is useful preoperative investigation for cholesteatoma surgery for identification and documentation of ossicular status, location and extent of disease, erosion of tegmen or sinus or labyrinthine dehiscence, with the exception of facial canal dehiscence. Although it serves as road map for surgery, it still has some false positives and false negatives and the importance of a skilful, aware and alert surgeon cannot be overemphasized. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12070-020-01892-z) contains supplementary material, which is available to authorized users.

ObjectiveTo investigate the prevalence of bony dehiscence in the tympanic facial canal in patients with acute otitis media with facial paresis compared to those without facial paresis.MethodA retrospective case–control study was conducted on acute otitis media patients with facial paresis undergoing high-resolution temporal bone computed tomography.ResultsForty-eight patients were included (24 per group). Definitive determination of the presence of a bony dehiscence was possible in 44 out of 48 patients (91.7 per cent). Prevalence of bony dehiscence in acute otitis media patients with facial paresis was not different from that in acute otitis media patients without facial paresis (p = 0.21). Presence of a bony dehiscence was associated with a positive predictive value of 66.7 per cent in regard to development of facial paresis. However, an intact bony tympanic facial canal did not prevent facial paresis in 44.8 per cent of cases (95 per cent confidence interval = 34.6–55.6).ConclusionPrevalence of bony dehiscence in acute otitis media patients with facial paresis did not differ from that in acute otitis media patients without facial paresis. An intact tympanic bony facial canal does not protect from facial paresis development.

Introduction: The aim of the study was to assess diagnostic role of High Resolution Multi-detector Computed Tomography (HRMDCT) of temporal bone in the evaluation of Chronic Suppurative Otitis Media (CSOM) and to correlate intraoperative and HRCT findings in CSOM in selective cases. Material and Methods: 57 patients presented with CSOM in ENT department, referred to Radio diagnosis department were included in this study. The suspected patients were subjected to HRCT of Temporal bone using GE Bright speed Elite16 multi slice CT machine with 0.6mm plain axial and coronal slices with multi planar reformations. Results: The reported findings were correlated with clinical and surgical findings in subset of cases. Sensitivity, Specificity of HRMDCT with respect to clinical and surgical correlation in selective cases was evaluated. Among 30 surgical cases, most of them were atticoantral (53.4%) followed by tubotympanic CSOM (46.6%). On surgical correlation, HRCT has a high sensitivity (84.36%), specificity (80%), PPV of 90.4% and accuracy of 90% in the diagnosis of type of CSOM. A significant association with p value Conclusion: a good sensitivity, specificity of HRCT of temporal bone has a major role in the diagnosis of type of CSOM with respect to surgical correlation. HRCT of Temporal bone affords essential information regarding the disease extent, associated complications, aiding clinicians in deciding the appropriate surgical planning and management, thereby making HRMDCT an essential pre workup diagnostic tool. Keywords: Temporal bone, Cholesteatoma, HRCT, Facial canal dehiscence.

Introduction Preoperative imaging is a standard practice for cochlear implant candidacy. We are discussing association between surgical feasibility and various anatomical details of middle and inner ear by both high-resolution computed tomography (HRCT) and 3T magnetic resonance imaging (MRI) in patients with bilateral sensorineural hearing loss (SNHL) and are used as a guide during surgery as well as foresee complications in cochlear implantation. Materials and Methods A total of 56 patients of aged 1 to 5 years (prelingual) and > 1 years (postlingual or perilingual) having bilateral SNHL were included in the study. HRCT temporal bone and MRI head was done in all candidates. Based on the imaging findings of CT and MRI, patients were divided into two categories (normal and abnormal). Demographic and clinical values were compared between two groups. Binary logistic regression analysis was used to identify the predictors of the outcome variable (surgical difficulty). Results Out of 56 patients, 55 underwent cochlear implantation by Veria technique, one patient having Michel’s deformity was denied surgery and was advised brain stem implant. Note that 69.1% patients had no radiological abnormality, while 30.9% patients showed abnormality including acquired disease and malformation. Out of the total study patients, 18% (n = 10) showed various type of congenital inner ear malformation. Large size of the external auditory canal (EAC), high basal turn angle (BTA), and increased distance between tympanic segment of facial canal to EAC (midpoint between level of I-S joint corresponding to EAC and exit of chordae tympanic at level of EAC), all these factors showed inverse relationship with difficulty in surgery, which were found to be statistically significant. Conclusion The imaging in cochlear implant patients is an essential tool for preoperative assessment of candidacy, surgical planning, and avoid intra- and postoperative complications. BTA and distance between tympanic segment of facial nerve and EAC (midpoint between level of I-S joint corresponding to EAC and exit of chordae tympanic at level of EAC) are important predictors for evaluating intra- and postoperative complications.

To perform an evidence-based review evaluating presenting symptoms, imaging, and management for primary paragangliomas of the facial canal (PPFCs).PubMed/MEDLINE, Embase, Cochrane Library, and Web of Science.Studies were assessed for quality of evidence and bias with the Cochrane bias tool, GRADE, and MINORS criteria. Demographic data, imaging modalities, management strategies, and status at last follow-up were obtained.Sixteen studies met inclusion criteria. In total, 21 patients with PPFCs were identified, 19 of which were histologically confirmed. Most common presenting symptoms included unilateral facial nerve dysfunction (n = 14, 73.7%) and pulsatile tinnitus (n = 8, 42.1%). Mean time from reported onset of facial dysfunction was 17.8 months. Computed tomography findings included an expanded descending facial nerve canal (n = 13, 76.5%). All cases with magnetic resonance imaging reported enhancement with contrast. Of the 18 patients who had surgery, 16 (88.9%) underwent full tumor resection while 1 (5.6%) had partial tumor debulking with adjuvant radiotherapy. Overall improvement in facial weakness was documented in 5 of 9 patients (55.6%) with initial facial nerve dysfunction and6-month follow-up. No evidence of tumor recurrence was reported.PPFCs are extraordinarily rare vascular neoplasms of the temporal bone. Early imaging with both computed tomography and magnetic resonance imaging is essential for narrowing the differential diagnosis, assessing the extent of tumor invasion, and accurate surgical planning. Surgical tumor resection with subsequent facial nerve reconstruction is recommended for patients with facial nerve dysfunction, while tumor biopsy or debulking may be indicated when normal facial movement in present.

Treatment for necrotizing otitis externa (NOE) includes long term antibiotic and surgery in selected cases. Indications and extent of surgery, however, are still not defined. The aims of this study were: (1) present our experience in surgery for NOE (2) compare high-resolution computer tomography and perioperative findings (3) suggest recommendations for indications and extent of surgery. A retrospective case series study was conducted in a tertiary referral center. Patients hospitalized due to NOE between the years 1990–2015 and underwent surgery were included. Twenty patients were included in the study. HRTBCT was performed in 17 patients. Most common radiological findings included mastoid fullness (n = 13, 76.4%) and edema of external ear canal (n = 12, 70.5%). Surgical indications included lack of response to treatment (n = 18) and facial nerve palsy (n = 2). Seven patients underwent local debridement. Most common operative findings included soft tissue necrosis (n = 4, 57.1%) and gross bony destruction of the external ear canal (n = 2, 28.5%). Thirteen patients underwent tympanomastoid surgery. Most common operative findings included granulation tissue in the mastoid (n = 7, 53.8%) and mastoid bony erosion (n = 4, 30.7%). Facial canal involvement was seen in four patients (30.7%). This is the first study to describe a large group of surgically treated NOE. Initial surgical approach should be based on clinical and HRTBCT findings. Minimal HRTBCT findings may be addressed with local debridement. Severe HRTBCT findings should be addressed with canal wall up mastoidectomy as the minimal surgical procedure. Further extent should be decided based on perioperative findings.

To correlate the pre-operative Temporal Bone High Resolution Computer Tomography (HRCT) Scan findings with intraoperative findings in Chronic Otitis Media—Squamous type. This prospective, correlative, observational study was done at Department of Otorhinolaryngology and Head and Neck Surgery, Tribhuvan University Teaching Hospital, Kathmandu. 156 patients underwent mastoid surgery under General Anaesthesia from October 2017 to November 2018. Ethical committee approval taken from the institutional review committee. Informed consent regarding the study was taken prior to surgery. The peroperative findings were correlated with preoperative HRCT findings. Cohen’s kappa coefficient (k-value) was used to estimate the degree of correlation. Statistical analysis was done using SPSS version 25. Total 156 patients between 8 and 70 years of age were enrolled in the study. Presence of cholesteatoma/granulation on HRCT scan was found with 100% sensitivity with k-value of 0.569 denoting fair agreement. Regarding ossicular status, malleus showed maximum k-value of 0.525 with sensitivity of 81.3% followed by stapes and incus with k-value of 0.308 and 0.380 and sensitivity of 68.3% and 70.2% respectively. Sinus plate status showed perfect radiosurgical agreement with k-value of 1.0 and sensitivity and specificity of 100%. Bony facial canal demonstrated slight agreement with k-value of 0.506 and sensitivity of 45.8%. Dural plate status showed fair agreement with k-value of 0.503 and sensitivity of 38.9%. For Lateral Semicircular Canal (LSCC) erosion, we found very good agreement with k-value of 0.893 with sensitivity of 90.9%. Preoperative HRCT scan temporal bone correlates well for the detection of disease presence and shows good radiosurgical agreement for sinus plate erosion, LSCC erosion but fair agreement for dural plate erosion and malleus erosion. Plain HRCT scan with 3-D reconstruction is a poor predictor of bony facial canal, incus and stapes erosion.

This review focuses on the etiology, incidence and therapy of delayed paralysis of the facial nerve (DFP) after different types of middle ear surgery. Retrospective review of studies published in English from 1970 until 2019 reporting DFP after tympanoplasty, tympanomastoid surgery, stapedotomy and stapedectomy. The search used the databases of PubMed, Scopus and Cochrane Library. Studies reporting from adult patients and DFP onset after 48 h after surgery were included. Studies dealing with iatrogenic or preexisting facial palsy and case reports were excluded. The initial literature search resulted in 52 studies. The relevance of the publications was verified using title, abstract and full-text analysis. Data were analyzed with descriptive statistics using median, simple sum and statistical significance. Ten studies having 12,161 patients could be included in this review. The incidence of DFP after the middle ear surgeries varies between 0.2 and 1.9%. The surgical stress of the middle ear surgeries is the main trigger for the development of DFP and leads to a virus reactivation and/or neuronal edema. Patients with a dehiscence of the facial canal have a significantly higher probability for a DFP. The recommended therapy of DFP based on the data of the therapy of Bell’s palsy, consists of the administration of a steroid. For patients having a case history of previous viral infections, an antiviral prophylaxis is recommended. Overall, DFP has a very good prognosis, with mostly complete healing with appropriate therapy. Viral reactivation is the most favored genesis of DFP. Immunization or antiviral prophylaxis is recommended to those patients being at risk for a viral reactivation.

Facial nerve tumors within the temporal bone present several surgical challenges due to the tortuous course of the facial nerve and the nerve’s close relationship to other important structures. Surgical approaches often have either sacrificed hearing/vestibular function or involved brain retraction. We present a case of a patient who was diagnosed with a facial nerve schwannoma (House-Brackmann IV/VI). Magnetic resonance imaging (MRI) showed the tumor was limited to the middle ear. The patient had already undergone facial reanimation procedures and elected to have the tumor removed. A transmastoid trans-facial canal surgical approach was used to remove the tumor without disturbing the ossicular chain. The patient’s hearing and vestibular function remained intact. Operating from within the facial canal provides the surgeon additional room to dissect facial nerve tumors from the middle ear to the geniculate ganglion when using a transmastoid approach. This surgical approach is similar to the previously described transmastoid/supralabyrinthine approach to excise facial nerve tumors within the temporal bone but modified to keep the ossicles intact. While the described approach has a limited application, in certain cases of facial nerve tumors within the temporal bone when surgery is warranted, a transmastoid trans-facial canal approach may have advantages over previously-described approaches.

Specific features of the sciurid auditory capsule have been analyzed based on 63 species from 20 genera. Its morphological specificity is characterized by a peculiar combination of primitive and advanced features stable within the group. They are (1) a rounded and inflated bulla with internal septa and a primitive attachment of the tympanic ring to the inner tympanic wall; (2) a transverse position of the bulla relative to the axis of the promontorium, resulting in the presence of deep petrosal fossae in front of and above the promontorium which are not covered by the tympanic bone; (3) a fully formed osseus facial canal and a developed bone tube of the stapedial artery; (4) the presence of a meato-cochlear bridge connecting the promontorium to the posterior wall of the acoustic duct which, in a fully developed form, does not occur in any other recent rodents; (5) pneumatization of the mastoid due to the expanding of the epitympanic chamber both anteriorly and posteriorly, with the formation of a premeatal pocket and a large epitympano-mastoid chamber divided into parts. The sciurid auditory capsule can generally be considered as morphologically advanced. Its diversity within the family concerns functionally significant features and is manifested in the structure of the external acoustic meatus, the size of the tympanic membrane, the length of the processes of auditory ossicles, and, most importantly, the degree of pneumatization of the auditory capsule. This is associated with quantitative variations of the characters and does not affect its structural plan, as a rule.

A symptomatic facial canal meningocele is a rare entity which poses a diagnostic dilemma for otologists, neurosurgeons and neuroradiologists. Computed tomography (CT) and magnetic resonance imaging (MRI) can assist with the diagnosis. Treatment options range from conservative management with interval imaging to surgical management, which must balance the risk of post-operative facial nerve paralysis. The preferred operative management in refractory meningitis cases, due to CSF leak, involves subtotal petrosectomy and blind sac closure. This report presents a case of child with a background of a Type 1 Arnold-Chiari malformation, who presented with a prolonged history over 8 years with presentations of recurrent meningitis, facial nerve palsy and unilateral sensorineural hearing loss. The unusual diagnosis of a facial nerve canal meningocele was made and subsequenently underwent a tympanomastoidectomy/subtotal petrosectomy and blind sac closure.