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Recurrent cholesteatoma. Axial diffusion-weighted image (a) demonstrates abnormal hyperintense signal in the left temporal bone consistent with a focus on recurrent cholesteatoma (white arrow). Axial T2-weighted sequence (b) shows fat packing material in the left temporal bone (arrowhead) following mastoidectomy with blind sac closure.
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Imaging plays a critical role in the evaluation of a number of facial nerve disorders. The facial nerve has a complex anatomical course; thus, a thorough understanding of the course of the facial nerve is essential to localize the sites of pathology. Facial nerve dysfunction can occur from a variety of causes, which can often be identified on imagi...
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Background
Facial nerve palsy is a cardinal manifestation of neurosarcoidosis, but dedicated studies of this disease feature have not been conducted. We sought to clarify the impact of facial palsy on the diagnosis of neurosarcoidosis, its subsequent clinicoradiographic evolution, and eventual treatment decisions.
Methods
A single-center retrospec...
PurposeFacial nerve electrodiagnostics is a well-established and important tool for decision making in patients with facial nerve diseases. Nevertheless, many otorhinolaryngologist—head and neck surgeons do not routinely use facial nerve electrodiagnostics. This may be due to a current lack of agreement on methodology, interpretation, validity, and...
Objective:
Bell's palsy, named after the Scottish anatomist, Sir Charles Bell, is the most common acute mono-neuropathy, or disorder affecting a single nerve, and is the most common diagnosis associated with facial nerve weakness/paralysis. Bell's palsy is a rapid unilateral facial nerve paresis (weakness) or paralysis (complete loss of movement)...
Bell's palsy is the most common diagnosis associated with facial nerve weakness or paralysis. However, not all patients with facial paresis/paralysis have Bell's palsy. Other common causes include treatment of vestibular schwannoma, head and neck tumours, iatrogenic injuries, Herpes zoster, or trauma. The approach to each of these conditions varies...
Laser acupuncture can be used to treat neurosensory alterations and motor disorders caused by dental treatments. This study aimed to review the existing literature on the effects of laser acupuncture on neuropathies in the context of dentistry and to search for treatment modalities in which this technique is used. This systematic review was conduct...
Citations
... 10 Cisternal, intracanalicular, labyrinthine, and parotid segments are not expected to enhance typically within the healthy subjects. 11 Due to venous plexus surrounding the facial nerve as normal facial nerve faintly enhances in the geniculate ganglion, tympanic, and mastoid segments. At our institution, standard MRI imaging for evaluation of the facial nerve includes an internal acustic canal (IAC) protocol with the following special sequences for facial nerve; an axial 3 mm, T1-weighted sequence of the IAC angled perpendicular to dorsal aspect of the brainstem; an axial constructive interference in the steady-state (CISS) sequence (.6 mm) from the occipital bone to superior petrous ridge. ...
Acute onset Facial palsy was reported in four vaccinated participants in the BNT162b2 (Pfizer-BioNTech) vaccine clinical trials published on December 10, 2020. So far, few cases of Facial palsy among the mRNA vaccine groups have been previously documented in the literature. Facial palsy is cited as medically attended adverse event following immunization on April 12, 2021, after the first dose of the approved Pfizer-BioNTech COVID-19 vaccines for preventive immunization for SARS-CoV-2 is administrated to the population in Turkey. This study is aimed to describe clinical and magnetic resonance imaging features of three patients, who developed acute onset peripheral facial paralysis after administration of the BNT162b2 vaccine, without any previous medical condition. The first patient presented with right sided facial palsy within the same day following the vaccine was administrated, while the second patient presented with left sided facial palsy 2 months after vaccination. The third patient, on the other hand, presented with right sided facial palsy and abducens nerve (CN VI) paralysis two days after vaccine was administrated.
... The aim of some studies has been to find anatomical landmarks. For example, Gupta et al. (2013) in India investigated radioanatomical landmark identification to localize the foramen ovale during surgery. They used 117 dry skull samples and measured 6 different radioanatomical distances. ...
... They used 117 dry skull samples and measured 6 different radioanatomical distances. In this way, they identified a number of reliable landmarks [13]. In our study, radioanatomical factors were examined crudely; although, it was possible to design a landmark using the measurements. ...
Introduction
Preservation of the facial nerve is of great importance in temporal bone surgeries. We intend to investigate the measurements of the radioanatomical factors related to the position of the facial nerve in accessing jugular foramen and internal carotid artery (ICA) in temporal bone of patients who were candidates for temporal high resolution computed tomography (HRCT) scan.
Methods
In this correlation cross-sectional study, samples were selected from patients referred to Amir Alam Hospital who were previously candidates for temporal HRCT. Radioanatomic factors were evaluated in three axial, coronal and sagittal views. Analyzes were performed using descriptive statistics, correlation analysis and factor analysis.
Results
A total of 173 samples were investigated. The most reliable radioanatomical factor based on coefficient of variation (CV) was the distance of the 7th nerve to the temporomandibular joint (TMJ) in the inferior to the cochlea in the sagittal view (variable name S2) (CV = 8.1%) and then the distance from the 7th nerve to the TMJ in the inferior section of the cochlea in the axial view (variable name AI3) (CV = 8.4%). Based on correlation analysis and then confirmatory factor analysis, three common latent factors were identified (overall R² = 0.999).
Conclusion
The results of this study can be used for two purposes. First, the direct use of the estimated measures in surgical operations, and the second is more advanced modeling to choose the approach in the surgical operation and how to implement that approach. For the first aim, the two factors AI3 and S2 were the most reliable radioanatomical factors in different people. For the second aim, the three-dimensional understanding of the obtained measurements and the further identification of the anatomical nature of the latent factors can help in choosing the approach in surgery.
... In such cases, indirect landmarks can be used to locate the course and plane of the nerve [11]. The orientation and integration of the white matter tracts and cranial nerve course within the brain can also be examined using tractography in vivo [12][13][14][15]. Still, unfortunately, it is not applicable for the extracranial branches of the facial nerve, except for 3D constructive interference in steady-state MRI, which is feasible for the previsualization of the facial nerve trunk and its primary divisions [16]. ...
(1) Background: Considering that the specialty literature supplies only general data about the variability of the cervical branch of the facial nerve, this study aimed to determine this branch’s variation and individual peculiarities depending on the nerve branching pattern and anthropometric type of the head. (2) Methods: The study was conducted on 75 hemifaces of adult formalized cadavers. Ahead of anatomical dissection, each head was measured to establish the anthropometric type, according to Franco and colleagues. The branching patterns were then distributed according to the Davis classification. (3) Results: The number of cervical branches (CB) of the facial nerve varied from one to five branches, with the following rate: 1 CB (61.3%), 2 CB (28%), 3 CB (6.7%), 4 CB (2.7%), and 5 CB (1.3%). Seven branching patterns of the facial nerve were revealed: Type I in 18.7%, Type II in 14.7%, Type III in 20%, Type IV in 14.6%, Type V in 5.3%, Type VI in 18.7%, and Type NI in 8% (bizarre types). According to the branching pattern, the mean numbers of the cervical branches were as follows: Type I—1.6 ± 1.02; Type II—1.4 ± 0.50; Type III—1.4 ± 0.50; Type IV—1.4 ± 0.67; Type V—2.0 ± 1.41; Type VI—1.8 ± 1.12; and Type-NI—1.8 ± 0.75; p = 0.599. According to the anthropometric type of the head, the mean number of CB in the mesocephalic type (MCT) was 1.5 ± 0.82, in the dolichocephalic type (DCT), 1.7 ± 0.87, and in the brachycephalic type, (BCT) 1.8 ± 1.04; p = 0.668. (4) Conclusions: The cervical branch of the facial nerve varies depending on the facial nerve branching pattern and the anthropometric type of the head. The highest degree of variation was characteristic of BCT and Type V and the lowest, of MCT and Types II, III, and IV.
... Preoperative analysis of the intra-parotid facial nerve pathway is not used in current practice. Several procedures have been described, using MRI with a gradient of 3 Tesla: anatomical 3D sequences, with positive contrast of the facial nerve using double water excitation and negative contrast, and tractography analysis using Diffusion MRI [6]. ...
Purpose
The objective of our study was to evaluate the ability of preoperative MRI tractography to visualize and predict the path of the facial nerve with respect to an intra-parotid mass.
Methods
We performed an observational bicentric study from June 2019 to August 2020. All patients older than 18 years old, treated for a parotid mass with surgical indication, without MRI contraindication and who agreed to participate in the study were enrolled prospectively. All patients underwent a cervico-facial MRI with tractographic analysis. Postprocessed tractography images of the intra-parotid facial nerve were analyzed by two expert radiologists in head and neck imaging. The intraoperative anatomical description of the facial nerve path and its relationship to the mass was performed by the surgeon during the operation, with no visibility on MRI examination results. A statistical study allowed for the description of the data collected as well as the measurement of inter-observer agreement and agreement between tractography and surgery using kappa coefficients.
Results
Fifty-two patients were included. The facial nerve trunk and its first two divisional branches were visualized via tractography in 93.5% of cases (n = 43). The upper distal branches were visualized in 51.1% of cases (n = 23), and the lower branches were visualized in 73.3% of cases (n = 33). Agreement with the location described per-operatively was on average 82.9% for the trunk, 74.15% for the temporal branch, and 75.21% for the cervico-facial branch.
Conclusion
Fiber tractography analysis by MRI of the intra-parotid facial nerve appears to be a good test for predicting the path of the nerve over the parotid mass and could be an additional tool to guide the surgeon in the operative procedure.
... Cerebral imaging may be considered to detect neoplastic processes or brainstem lesions [15]. Electrophysiological procedures provide evidence of early hypoexcitability in the facial canal (typical in idiopathic PFP), but this is not specific for the etiology of PFP [16]. ...
Background
Peripheral facial palsy (PFP) is a common neurologic symptom which can be triggered by pathogens, autoimmunity, trauma, tumors, cholesteatoma or further local conditions disturbing the peripheral section of the nerve. In general, its cause is often difficult to identify, remaining unknown in over two thirds of cases. As we have previously shown that the quantity and quality of pathogen-specific T cells change during active infections, we hypothesized that such changes may also help to identify the causative pathogen in PFPs of unknown origin.
Methods
In this observational study, pathogen-specific T cells were quantified in blood samples of 55 patients with PFP and 23 healthy controls after stimulation with antigens from varicella-zoster virus (VZV), herpes-simplex viruses (HSV) or borrelia. T cells were further characterized by expression of the inhibitory surface molecule CTLA-4, as well as markers for differentiation (CD27) and proliferation (Ki67). Pathogen-specific antibody responses were analyzed using ELISA. Results were compared with conventional diagnostics.
Results
Patients with PFP were more often HSV-seropositive than controls ( p = 0.0003), whereas VZV- and borrelia-specific antibodies did not differ between groups. Although the quantity and general phenotypical characteristics of antigen-specific T cells did not differ either, expression of CTLA-4 and Ki67 was highly increased in VZV-specific T cells of 9 PFP patients, of which 5 showed typical signs of cutaneous zoster. In the remaining 4 patients, a causal relationship with VZV was possible but remained unclear by clinical standard diagnostics. A similar CTLA-4- and Ki67-expression profile of borrelia-specific T cells was also found in a patient with acute neuroborreliosis.
Discussion
In conclusion, the high prevalence of HSV-seropositivity among PFP-patients may indicate an underestimation of HSV-involvement in PFP, even though HSV-specific T cell characteristics seem insufficient to identify HSV as a causative agent. In contrast, striking alterations in VZV- and borrelia-specific T cell phenotype and function may allow identification of VZV- and borrelia-triggered PFPs. If confirmed in larger studies, antigen-specific immune-phenotyping may have the potential to improve specificity of the clinical diagnosis.
... Imaging tools commonly used in preoperative assessment are ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI). The choice of the imaging modality utilized in the assessment of the facial nerve and relation with other anatomical or pathological structures is dependent on the differential diagnosis, patient status, localization of the pathological entity and purpose of the investigation (41). ...
... As is common practice in numerous countries, CT scans together with ultrasounds are the first choice of imaging investigations in cases of patients clinically diagnosed with parotid tumour. When using CT to evaluate the facial nerve, high-resolution temporal bone CT may offer valuable information regarding the intra-fallopian segment of the facial nerve to the stylomastoid foramen, but the intratemporal part of the nerve may be indirectly assessed, only if the pathological entity determined bone erosion or destruction (41). For the assessment of the extratemporal segment of the facial nerve, MRI has proven to be a more accurate imaging examination. ...
For patients diagnosed with advanced malignant parotid tumour, radical parotidectomy with facial nerve sacrifice is part of the treatment. Multiple surgical techniques have been developed to cure facial paralysis in order to restore the function and aesthetics of the face. Despite the large number of publications over time on facial nerve reanimation, a consensus on the timing of the procedure or the donor graft selection has remained to be established. Therefore, the aim of the present study was to conduct a bibliometric analysis to identify and analyse scientific publications on the reconstruction of the facial nerve of patients who underwent radical parotidectomy with facial nerve sacrifice. The analysis on the topic was conducted using the built-in tool of the Scopus database and VOSviewer software. The first 100 most cited articles were separately reviewed to address the aim of the study. No consensus was found regarding the recommended surgical techniques for facial nerve reanimation. The most used donor cranial nerves for transfer included the following: Masseteric branch of the V nerve, contralateral VII nerve with cross-face graft, the XI nerve and the XII nerve. The best timing of surgery is also controversial depending on pre-exiting pathology and degree of nerve degeneration. However, most of the clinical experience suggests facial nerve restoration immediately after the ablative procedure to reduce complications and improve patients' quality of life.
... The labyrinthine segment, which has been measured on average below 0.7 mm, is the narrowest portion of the canal. That the bony canal confines the expansion of the facial nerve caused by edema or inflammation has been speculated as the etiology of Bell's palsy, especially in the labyrinthine segment 13 . However, there is no direct evidence for the pathogenesis of Bell's palsy. ...
To explore the pathogenesis of Bell's palsy using the diffusion tensor image on 3.0 T MR. The healthy people and the patients with Bell's palsy underwent intraparotid facial nerve scanning by using the DTI and T1 structural sequence at 3.0 T MR. The raw DTI data were performed affine transformation and nonlinear registration in the common MNI152_T1 space and resampled to the 0.4 mm³ voxel size. A group of 4 spherical seed regions were placed on the intratemporal facial nerves in the common space, bilaterally and symmetrically. The DTI data in the common space were used to track the intratemporal facial nerve fibers by using TrackVis and its Diffusion Toolkit. Each tractography was used to construct the maximum probability map (MPM) according to the majority rule. The fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) were calculated and extracted on the basis of MPM. For healthy people, there was no significant difference in FA, MD, RD and AD of bilateral facial nerves. For patients with Bell's palsy, there was no significant difference in AD, there was significant difference in FA, MD and RD between the affected nerve and the healthy nerve (P < 0.02). This study showed that the myelin sheath injury of the intratemporal facial nerve is the main cause of Bell's palsy. Most neural axons are not damaged. The results may explain the pathogenesis of the Bell's palsy, which is self-limited for most cases.
... CT imaging is often obtained during trauma evaluation and can identify osseous injuries around the intratemporal segment of the facial nerve. Temporal bone injuries are best discerned with this imaging modality, with dedicated temporal bone CT scans offering higher specificity for fractures compared to Magnetic Resonance Imaging (MRI) [14] . MRI can provide highly detailed images of soft tissues, with specialized sequences offering high-resolution detail that is important for discerning nerve injuries. ...
... Gupta et al. describe a protocol of non-contrast HRCT with 0.3 mm axial slices through both temporal bones, as well as 0.6 mm coronal sections and Poschl reformats, with dose settings of 120 kVp and CTDI volume of 55.5-62.6 and 140-220 mAs [15] . Mu et al. described a correlation between enlarged geniculate ganglion fossa and fracture of the temporal bone in this region in patients with traumatic facial palsy [14] . ...
Traumatic facial nerve injuries can result in temporary or permanent loss of function. Restoration of facial expression may occur spontaneously or require surgical intervention. Although thorough examination and history can localize the site of facial nerve damage, it can be difficult to predict if and when recovery will occur. This is salient because the window for optimal outcomes from surgical re-neurotization can be as short as 1 to 2 years, after which functional loss may be irreversible. It is essential to offer patients the most appropriate treatment plan based on prognosis, and imaging plays an essential role in localizing the site and morphology of nerve injury. Multiple imaging modalities have been used to evaluate the facial nerve, including Computed Tomography (CT) and, more recently, advanced Magnetic Resonance Imaging (MRI) and Ultrasound (US). CT and MRI are more commonly implemented; however, Diffusion Tensor Tractography, high-resolution US, and functional US are gaining traction for studying cranial nerve pathology. Until recently, the morphology of facial nerve and other cranial nerve injuries could only be inferred using non-invasive diagnostic techniques. With the advent of newer imaging technologies and techniques to examine nerves, more refined assessment and prognostic information is now possible. This article reviews up-to-date cranial nerve imaging techniques from the last ten years and explores future avenues for facial nerve imaging.
... Additionally, we observed a notable discrepancy in the kappa value concerning facial canal erosion, indicating a stronger association in the vertical part of the facial canal compared to the horizontal part. We postulate that the relatively shorter and more tortuous nature of the horizontal facial canal, in contrast to the vertical part, gives rise to this anatomical complexity [13]. Consequently, this complexity can pose challenges in achieving accurate imaging and interpretation on HRCT. ...
Introduction: Cholesteatoma, a hazardous non-neoplastic lesion of the temporal bone, is prevalent in socio-economically disadvantaged groups in developing nations like India. Timely detection and surgical intervention are essential for effective management. High-resolution computed tomography (HRCT) has revolutionized the assessment of temporal bone pathology, though its role in preoperative evaluation remains debated. This study aimed to validate HRCT's utility in diagnosing cholesteatoma, compare its findings with intraoperative observations, and assess sensitivity and specificity.
Methods: This diagnostic accuracy study was conducted at a tertiary care center in Western India, from March 2021 to November 2022. HRCT findings of 54 cholesteatoma patients were evaluated and compared with intraoperative findings. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and Cohen's kappa coefficient were calculated.
Results: HRCT demonstrated a sensitivity exceeding 90% in identifying scutum erosion, mastoid sclerosis, and abnormalities in the tympanic membrane, along with a specificity surpassing 90% in detecting various conditions, including facial canal erosion, sinus plate erosion, lateral semicircular canal erosion, erosion of the posterior wall of the external auditory canal, and abnormalities in the tympanic membrane. Furthermore, HRCT exhibited an accuracy of over 90% in detecting most pathologies. There was a perfect or near-perfect agreement observed for abnormal tympanic membrane, sinus plate erosion, mastoid sclerosis, and erosion of the posterior wall of the external auditory canal (with kappa values > 0.8). Moderate to fair agreement was noted for other pathologies.
Conclusion: HRCT offered precise detection of the majority of pathologies, thereby facilitating surgical planning. However, the presence of limitations in distinguishing specific abnormalities highlights the significance of utilizing HRCT in tandem with other diagnostic modalities to ensure meticulous diagnosis and effective treatment planning.
... Congenital malformations of the facial nerve (FN) are uncommon [1]. Bifurcation of the FN is specially rare, but has been described in all its segments [1]. ...
... Congenital malformations of the facial nerve (FN) are uncommon [1]. Bifurcation of the FN is specially rare, but has been described in all its segments [1]. The most common bifurcation affects the tympanic segment, typically above the oval window [1]. ...
... Bifurcation of the FN is specially rare, but has been described in all its segments [1]. The most common bifurcation affects the tympanic segment, typically above the oval window [1]. However, only one case has been described in the labyrinthine segment [1,2]. ...
The labyrinthine bifurcation of the facial nerve is extremely rare. Diverse congenital temporal bone anomalies usually coexist, and a detailed preoperative evaluation is needed to detect them. We report a case of labyrinthine bifurcation of the facial nerve detected on the preoperative evaluation of a patient with congenital aural atresia.
