A 3.8-million-year-old hominin cranium from Woranso-Mille, Ethiopia.

The cranial morphology of the earliest known hominins in the genus Australopithecus remains unclear. The oldest species in this genus (Australopithecus anamensis, specimens of which have been dated to 4.2-3.9 million years ago) is known primarily from jaws and teeth, whereas younger species (dated to 3.5-2.0 million years ago) are typically represented by multiple skulls. Here we describe a nearly complete hominin cranium from Woranso-Mille (Ethiopia) that we date to 3.8 million years ago. We assign this cranium to A. anamensis on the basis of the taxonomically and phylogenetically informative morphology of the canine, maxilla and temporal bone. This specimen thus provides the first glimpse of the entire craniofacial morphology of the earliest known members of the genus Australopithecus. We further demonstrate that A. anamensis and Australopithecus afarensis differ more than previously recognized and that these two species overlapped for at least 100,000 years-contradicting the widely accepted hypothesis of anagenesis.

Sphenomandibular ligament and degenerating Meckel's cartilage revisited: Sequential variations with temporal bone deformity for ligament attachment in near-term human fetuses.

BACKGROUND: The sphenomandibular ligament (SML) is considered to originate from Meckel's cartilage (MC). However, no study has examined how the os goniale contributes to SML development. METHODS: Semiserial histological sections of heads from 18 near-term fetuses at 27-40 weeks of gestation were examined. OBSERVATIONS: The os goniale and the anterior process of the malleus (AP) provided a long, bar-like membranous bone complex that passed through the petrotympanic and tympanosquamosal fissures. Notably, the AP-goniale complex is sometimes elongated inferiorly to join the SML (n = 4 specimens). Along the complex in the bone fissures, a degenerating MC was often present (n = 12). With (n = 6) or without (n = 3) the MC remnant, the tympanic bone (TYB) protruded inferomedially near the tympanosquamosal fissure, and it sometimes continued to a cartilaginous SML (n = 3). The temporal bone squamosa or petrosa provided a similar bony process approaching the SML. The middle meningeal artery often ran between the sphenoid and petrosa. CONCLUSIONS: Most of the specimens (n = 15) exhibited a sequential change from a cartilaginous SML as a continuation of the MC remnant to the ligament after the disappearance of the cartilage. The degenerating MC appeared to cause transformation from the AP-goniale complex and/or TYB to "another ligament" that replaced the usual SML at the upper part. Near the MC remnant, a similar transformation was also suggested on the squamosa or petrosa. The sphenoid spine appeared to originate often from the sphenoid ala major but sometimes from the TYB.

Skull fractures by glass bottles tested on cadaveric heads.

Head trauma is frequently related to the misuse of drinking vessels as weapons. Forensic reports usually evaluate these blunt injuries as having occurred in scenarios where the alcohol intake is high. Fatal consequences are seen in blows with glass bottles aiming at the head. To prove the outcome that a glass bottle thrown to the head could cause, three intact human cadaver heads were impacted with 1-liter glass bottles at 9.5 m/s using a drop-tower. The impact location covered the left temporal bone, sphenoid bone, and zygomatic arch. The contact between the head and the bottle was produced at an angle of 90° with (1) the valve of the bottle, (2) the bottom of the bottle, and (3) with the head rotated 20° in the frontal plane touching again with the bottom of the bottle. The three bottles remained intact after the impact, and the injury outcomes were determined by computed tomography (CT). The alterations were highly dependent on the impact orientation. The outcome varied from no injury to severe bone fractures. In the most injurious case (#3), fractures were identified in the cranial base, sphenoid bone, and zygomatic bone. These testing conditions were selected to replicate one specific legal case, as required by the plaintiff. Physical disputes with bar glassware can lead to complex combinations of blunt and sharp-force injuries. Controlled biomechanical studies can benefit forensic analyses of violence involving glassware by providing a better understanding of the underlying injury mechanisms.

Convexity subarachnoid hemorrhage revealed contralateral internal carotid artery dissection due to Eagle syndrome: a case report.

BACKGROUND: Atraumatic localized convexity subarachnoid hemorrhage (cSAH) is an uncommon form of nonaneurysmal subarachnoid hemorrhage characterized by bleeding limited to the cerebral convexities. Ipsilateral cSAH can result from a variety of causes, such as internal carotid artery stenosis, obstruction, and dissection, although concomitant contralateral cSAH is exceptionally rare. In this case, the initial findings of cSAH led us to discovering contralateral internal carotid artery dissection (ICAD) and an elongated styloid process (ESP). ESP is recognized as a risk factor for ICAD, which is a hallmark of Eagle syndrome. This sequence of findings led to the diagnosis of Eagle syndrome, illustrating a complex and intriguing interplay between cerebrovascular conditions and anatomical variations. CASE PRESENTATION: A 47-year-old Japanese woman experienced acute onset of headache radiating to her neck, reaching its zenith approximately two hours after onset. Given the intractable nature of the headache and its persistence for three days, she presented to the emergency department. Neurological examination revealed no abnormalities, and the coagulation screening parameters were within normal ranges. Brain computed tomography (CT) revealed right parietal cSAH, while CT angiography (CTA) revealed ICAD and an ESP measuring 30.1 mm on the left side, positioned only 1.4 mm from the dissected artery. The unusual occurrence of contralateral cSAH prompted extensive and repeated imaging reviews that excluded reversible cerebral vasoconstriction syndrome (RCVS), leading to a diagnosis of left ICAD secondary to Eagle syndrome. The patient underwent conservative management, and the dissected ICA spontaneously resolved. The patient has remained recurrence-free for two and a half years. CONCLUSIONS: Managing cSAH requires diligent investigation for ICAD, extending beyond its identification to explore underlying causes. Recognizing Eagle syndrome, though rare, as a potential etiology of ICAD necessitates the importance of evaluating ESPs. The method for preventing recurrent cervical artery dissection due to Eagle syndrome is controversial; however, conservative management is a viable option.

Deep learning reconstruction for high-resolution computed tomography images of the temporal bone: comparison with hybrid iterative reconstruction.

PURPOSE: We investigated whether the quality of high-resolution computed tomography (CT) images of the temporal bone improves with deep learning reconstruction (DLR) compared with hybrid iterative reconstruction (HIR). METHODS: This retrospective study enrolled 36 patients (15 men, 21 women; age, 53.9 ± 19.5 years) who had undergone high-resolution CT of the temporal bone. Axial and coronal images were reconstructed using DLR, HIR, and filtered back projection (FBP). In qualitative image analyses, two radiologists independently compared the DLR and HIR images with FBP in terms of depiction of structures, image noise, and overall quality, using a 5-point scale (5 = better than FBP, 1 = poorer than FBP) to evaluate image quality. The other two radiologists placed regions of interest on the tympanic cavity and measured the standard deviation of CT attenuation (i.e., quantitative image noise). Scores from the qualitative and quantitative analyses of the DLR and HIR images were compared using, respectively, the Wilcoxon signed-rank test and the paired t-test. RESULTS: Qualitative and quantitative image noise was significantly reduced in DLR images compared with HIR images (all comparisons, p ≤ 0.016). Depiction of the otic capsule, auditory ossicles, and tympanic membrane was significantly improved in DLR images compared with HIR images (both readers, p ≤ 0.003). Overall image quality was significantly superior in DLR images compared with HIR images (both readers, p < 0.001). CONCLUSION: Compared with HIR, DLR provided significantly better-quality high-resolution CT images of the temporal bone.

Development of an Algorithm for Correct Placement of the Basal Electrode Contact in the Context of Anatomy-Based Cochlear Implantation: A Proof of Concept.

BACKGROUND: Correct individual tonotopic frequency stimulation of the cochlea plays an important role in the further development of anatomy-based cochlear implantation. In this context, frequency-specific fitting of the basal electrode contact with a normal insertion depth can be difficult since it is often placed in a frequency range higher than 10 kHz, and current audio processors only stimulate for frequencies up to 8.5 kHz due to microphone characteristics. This results in a mismatch of the high frequencies. Therefore, this study represents a proof of concept for a tonotopic correct insertion and aims to develop an algorithm for a placement of the basal electrode below 8.5 kHz in an experimental setting. METHODS: Pre- and postoperative flat-panel volume CT scans with secondary reconstructions were performed on 10 human temporal bone specimens. The desired frequency location for the most basal electrode contact was set at 8.25 kHz. The distance from the round window to the position where the basal electrode contact was intended to be located was calculated preoperatively using 3D-curved multiplanar reconstruction and a newly developed mathematical approach. A specially designed cochlear implant electrode array with customized markers imprinted on the silicone of the electrode array was inserted in all specimens based on the individually calculated insertion depths. All postoperative measurements were additionally validated using otological planning software. RESULTS: Positioning of the basal electrode contact was reached with only a small mean deviation of 37 ± 399 Hz and 0.06 ± 0.37 mm from the planned frequency of 8.25 kHz. The mean rotation angle up to the basal electrode contact was 51 ± 5°. In addition, the inserted electrode array adequately covered the apical regions of the cochleae. CONCLUSION: Using this algorithm, it was possible to position the basal electrode array contact in an area of the cochlea that could be correctly stimulated by the existing speech processors in the context of tonotopic correct fitting.

Analysis of Cochlear Morphology for Cochlear Implantation Using Three-Dimensional Reconstruction of Computed Tomography Images.

INTRODUCTION: Preoperative evaluation of cochlear morphology is important for successful cochlear implantation. This study analyzed the cochlear canal by three-dimensional reconstructions of temporal bones using computed tomography (CT). METHODS: Fifty temporal bones from 25 patients aged 42-74 years were evaluated. The inner spaces of the bony cochlea were reconstructed using a surface rendering technique on the CT images. Eight angular points (P0-P7) every 90° were selected from 0° to 630° from the center of the round window using the reconstructed cochlear canal images. The radius (R) and thickness (T) of the cochlear canal at each point were measured. The cochlear canal length (CoCL) was estimated using an equation based on the radius at each point. The cochlear width and height based on multiplanar CT images were also measured and compared with the length and volume of the cochlear canal. RESULTS: The mean CoCL from 0° to 630° was 31.5 mm, and the cochlear volume was 55.9 mm3. The CoCL to P7 was correlated with the cochlear volume (r = 0.77), coiling ratios (R4/R0, r = 0.47; R5/R1, r = 0.384), cochlear width (long) (r = 0.539), cochlear height (r = 0.385), and total thickness at each point (r = 0.475). The cochlear volume was correlated with CoCL (630°) (r = 0.77), coiling ratio (R4/R0, r = 0.367), cochlear width (long) (r = 0.616), cochlear height (r = 0.447), and total T (r = 0.566). CONCLUSION: Preoperative evaluation using three-dimensional reconstruction can elucidate the size and shape of the cochlear canal before cochlear implantation.

Achieving Cochlear Therapeutic Hypothermia through Irrigation of the Mastoid and Tympanic Cavities.

INTRODUCTION: Mild therapeutic hypothermia (MTH) is an exciting nonpharmaceutical otoprotection strategy. In this study, we applied simple irrigation of the tympanic and mastoid cavities to understand the timing of both achieving MTH and recovery back to euthermic temperatures for application in the clinical setting. METHODS: Three human temporal bones were used in this study in the temporal bone laboratory. A standard mastoidectomy was performed on each followed by the insertion of temperature probes into the basal turn of the cochlea via a middle cranial fossa approach. The temporal bones were warmed in heated bead baths to 37°C. The tympanic and mastoid cavities were then irrigated with room temperature water, and intracochlear temperature readings were recorded every minute. After 15 min, irrigation was stopped, and temperature readings were collected until temporal bones returned to euthermic levels. RESULTS: Intracochlear MTH was achieved within the first minute of irrigating the tympanic and mastoid cavities. Intracochlear temperatures plateaued after 5 min around 30°C. Discontinuation of irrigation resulted in the temperature rising logarithmically above the MTH levels after 9-10 min. CONCLUSION: Intracochlear MTH can be achieved via irrigation of the tympanic and mastoid cavities with room temperature irrigation within 60 s. After irrigation for 5 min, hypothermic temperatures will remain therapeutic for 10 min following cessation of irrigation.

Cochlear Implant: Analysis of the Frequency-to-Place Mismatch with the Table-Based Software OTOPLAN® and Its Influence on Hearing Performance.

OBJECTIVE: The purpose of this study was to compare the originally applied frequency allocation of cochlear implant electrodes assigned by default at the time of activation with a more recent frequency allocation that is anatomy-based by a software called OTOPLAN®. Based on a computed tomography scan of the temporal bone, this software calculates the position of each electrode in the cochlea and its corresponding tonotopic frequency. We also evaluated whether patients with a significant mismatch between these two allocations present poorer speech intelligibility. MATERIALS AND METHODS: Patients who underwent cochlear implantation from 2016 to 2021 at the University Hospital of Liege were included in this retrospective study. We used OTOPLAN® to calculate the tonotopic frequency allocation of each electrode according to its exact position in the cochlear duct. This anatomical frequency mapping was compared with the default frequency mapping at the time of cochlear implant activation. Finally, we compared the mismatch with the patients' auditory performance, represented by the Auditory Capacity Index (ACI). RESULTS: Thirteen patients were included in the study. All patients had a mismatch between the two frequency maps, to a variable extent (200 Hz-1,100 Hz). Frequency shift was significantly inversely correlated with ACI and with the time needed to improve speech intelligibility. CONCLUSION: Our primary results show that patients with a larger mismatch between default frequency mapping and anatomically assigned frequency mapping experience poorer hearing performance and slower adaptation to a cochlear implant.

Numerical Simulations of the Epley Maneuver With Clinical Implications.

OBJECTIVES: Canalith repositioning procedures to treat benign paroxysmal positional vertigo are often applied following standardized criteria, without considering the possible anatomical singularities of the membranous labyrinth for each individual. As a result, certain patients may become refractory to the treatment due to significant deviations from the ideal membranous labyrinth, that was considered when the maneuvers were designed. This study aims to understand the dynamics of the endolymphatic fluid and otoconia, within the membranous labyrinth geometry, which may contribute to the ineffectiveness of the Epley maneuver. Simultaneously, the study seeks to explore methods to avoid or reduce treatment failure. DESIGN: We conducted a study on the Epley maneuver using numerical simulations based on a three-dimensional medical image reconstruction of the human left membranous labyrinth. A high-quality micro-computed tomography of a human temporal bone specimen was utilized for the image reconstruction, and a mathematical model for the endolymphatic fluid was developed and coupled with a spherical particle model representing otoconia inside the fluid. This allowed us to measure the position and time of each particle throughout all the steps of the maneuver, using equations that describe the physics behind benign paroxysmal positional vertigo. RESULTS: Numerical simulations of the standard Epley maneuver applied to this membranous labyrinth model yielded unsatisfactory results, as otoconia do not reach the frontside of the utricle, which in this study is used as the measure of success. The resting times between subsequent steps indicated that longer intervals are required for smaller otoconia. Using different angles of rotation can prevent otoconia from entering the superior semicircular canal or the posterior ampulla. Steps 3, 4, and 5 exhibited a heightened susceptibility to failure, as otoconia could be accidentally displaced into these regions. CONCLUSIONS: We demonstrate that modifying the Epley maneuver based on the numerical results obtained in the membranous labyrinth of the human specimen under study can have a significant effect on the success or failure of the treatment. The use of numerical simulations appears to be a useful tool for future canalith repositioning procedures that aim to personalize the treatment by modifying the rotation planes currently defined as the standard criteria.

Comparison of 96-kV and 120-kV cone-beam CT for the assessment of cochlear implants.

BACKGROUND: To compare the diagnostic value of 120-kV with conventional 96-kV Cone-Beam CT (CBCT) of the temporal bone after cochlear implant (CI) surgery. METHODS: This retrospective study included CBCT scans after CI surgery between 06/17 and 01/18. CBCT allowed examinations with 96-kV or 120-kV; other parameters were the same. Two radiologists independently evaluated following criteria on 5-point Likert scales: osseous spiral lamina, inner and outer cochlear wall, semi-circular canals, mastoid trabecular structure, overall image quality, metal and motion artefacts, depiction of intracochlear electrode position and visualisation of single electrode contacts. Effective radiation dose was assessed. RESULTS: Seventy-five patients (females, n = 39 [52.0%], mean age, 55.8 ± 16.5 years) were scanned with 96-kV (n = 32, 42.7%) and 120-kV (n = 43, 57.3%) protocols including CI models from three vendors (vendor A n = 7; vendor B n = 43; vendor C n = 25). Overall image quality, depiction of anatomical structures, and electrode position were rated significantly better in 120-kV images compared to 96-kV (all p < = 0.018). Anatomical structures and electrode position were rated significantly better in 120-kV CBCT for CI models from vendor A and C, while 120-kV did not provide improved image quality in CI models from vendor B. Radiation doses were significantly higher for 120-kV scans compared to 96-kV (0.15 vs. 0.08 mSv, p < 0.001). CONCLUSIONS: 120-kV and 96-kV CBCT provide good diagnostic images for the postoperative CI evaluation. While 120-kV showed improved depiction of temporal bone and CI electrode position compared to 96-kV in most CI models, the 120-kV protocol should be chosen wisely due to a substantially higher radiation exposure.

Clinical application of high-resolution spiral CT scanning in the diagnosis of auriculotemporal and ossicle.

Precision and intelligence in evaluating the complexities of middle ear structures are required to diagnose auriculotemporal and ossicle-related diseases within otolaryngology. Due to the complexity of the anatomical details and the varied etiologies of illnesses such as trauma, chronic otitis media, and congenital anomalies, traditional diagnostic procedures may not yield accurate diagnoses. This research intends to enhance the diagnosis of diseases of the auriculotemporal region and ossicles by combining High-Resolution Spiral Computed Tomography (HRSCT) scanning with Deep Learning Techniques (DLT). This study employs a deep learning method, Convolutional Neural Network-UNet (CNN-UNet), to extract sub-pixel information from medical photos. This method equips doctors and researchers with cutting-edge resources, leading to groundbreaking discoveries and better patient healthcare. The research effort is the interaction between the CNN-UNet model and high-resolution Computed Tomography (CT) scans, automating activities including ossicle segmentation, fracture detection, and disruption cause classification, accelerating the diagnostic process and increasing clinical decision-making. The suggested HRSCT-DLT model represents the integration of high-resolution spiral CT scans with the CNN-UNet model, which has been fine-tuned to address the nuances of auriculotemporal and ossicular diseases. This novel combination improves diagnostic efficiency and our overall understanding of these intricate diseases. The results of this study highlight the promise of combining high-resolution CT scanning with the CNN-UNet model in otolaryngology, paving the way for more accurate diagnosis and more individualized treatment plans for patients experiencing auriculotemporal and ossicle-related disruptions.

The short- and long-term effects of congenital occlusion loss of the unilateral first permanent molar on the temporomandibular joint morphology and position: A retrospective study based on cone-beam computed tomography.

OBJECTIVE: To investigate the effects of congenital unilateral first permanent molar occlusal loss (CUMOL) on the morphology and position of temporomandibular joint (TMJ). MATERIALS AND METHODS: Cone-beam computed tomography (CBCT) images of 37 patients with CUMOL (18 males and 19 females, mean age: 13.60 ± 4.38 years) were divided into two subgroups according to the status of second molar (G1: the second molar not erupted, n = 18, G2: second molar erupted, n = 19). The control group consisted of 33 normal occlusion patients (9 males and 24 females, mean age: 16.15 ± 5.44 years) and was divided into 2 subgroups accordingly (G3: the second molar had not erupted, n = 18, G4: the second molar had erupted and made contact with the opposing tooth, n = 15). Linear and angular measurements were used to determine the characteristics of TMJ. RESULTS: In G1, the condyle on the side of the CUMOL shifts posteriorly, with significant side differences observed in Anterior space (AS, P < .05) and Posterior space (PS, P < .05). However, with the eruption of the second permanent molars, in G2, the condyle on the CUMOL side moves posteriorly and inferiorly. This results in significant lateral differences in the AS (P < .05), PS (P < .05), and Superior space (SS, P < .05). Additionally, there is an increase in the thickness of the roof of the glenoid fossa (TRF) on the CUMOL side (P < .05), and a decrease in the inclination of the bilateral articular eminences (P < .05). CONCLUSIONS: CUMOL can affect the position and the morphology of the condyle and was associated with the eruption of the second permanent molars. Before the eruption of the second permanent molars, CUMOL primarily affects the position of the condyle. After the emergence of the second permanent molars, CUMOL leads to changes in both the condyle's position and the morphology of the glenoid fossa.

Eagle jugular syndrome accompanied by de novo brainstem cavernous malformation: a case-based systematic review.

BACKGROUND: Eagle jugular syndrome (EJS), recently identified as a cause of cerebrovascular disease (CVD) due to venous obstruction by an elongated styloid process (SP), is reported here alongside a case of concurrent de novo cerebral cavernous malformation (CCM). This study aims to explore the potential causal relationship between EJS and de novo CCM through a comprehensive literature review. METHOD: Systematic literature reviews, spanning from 1995 to 2023, focused on EJS cases with definitive signs and symptoms and de novo CCM cases with detailed clinical characteristics. Data on the pathophysiology and clinical manifestations of EJS, as well as potential risk factors preceding de novo CCM, were collected to assess the relationship between the two conditions. RESULT: Among 14 patients from 11 articles on EJS, the most common presentation was increased intracranial hypertension (IIH), observed in 10 patients (71.4%), followed by dural sinus thrombosis in four patients (28.6%). In contrast, 30 patients from 28 articles were identified with de novo CCM, involving 37 lesions. In these cases, 13 patients developed CCM subsequent to developmental venous anomalies (43%), seven following dural arteriovenous fistula (dAVF) (23%), and two after sinus thrombosis (6%). In a specific case of de novo brainstem CCM, the development of an enlarged condylar emissary vein, indicative of venous congestion due to IJV compression by the elongated SP, was noted before the emergence of CCM. CONCLUSION: This study underscores that venous congestion, a primary result of symptomatic EJS, might lead to the development of de novo CCM. Thus, EJS could potentially be an indicator of CCM development. Further epidemiological and pathophysiological investigations focusing on venous circulation are necessary to clarify the causal relationship between EJS and CCM.

A 3D and Explainable Artificial Intelligence Model for Evaluation of Chronic Otitis Media Based on Temporal Bone Computed Tomography: Model Development, Validation, and Clinical Application.

BACKGROUND: Temporal bone computed tomography (CT) helps diagnose chronic otitis media (COM). However, its interpretation requires training and expertise. Artificial intelligence (AI) can help clinicians evaluate COM through CT scans, but existing models lack transparency and may not fully leverage multidimensional diagnostic information. OBJECTIVE: We aimed to develop an explainable AI system based on 3D convolutional neural networks (CNNs) for automatic CT-based evaluation of COM. METHODS: Temporal bone CT scans were retrospectively obtained from patients operated for COM between December 2015 and July 2021 at 2 independent institutes. A region of interest encompassing the middle ear was automatically segmented, and 3D CNNs were subsequently trained to identify pathological ears and cholesteatoma. An ablation study was performed to refine model architecture. Benchmark tests were conducted against a baseline 2D model and 7 clinical experts. Model performance was measured through cross-validation and external validation. Heat maps, generated using Gradient-Weighted Class Activation Mapping, were used to highlight critical decision-making regions. Finally, the AI system was assessed with a prospective cohort to aid clinicians in preoperative COM assessment. RESULTS: Internal and external data sets contained 1661 and 108 patients (3153 and 211 eligible ears), respectively. The 3D model exhibited decent performance with mean areas under the receiver operating characteristic curves of 0.96 (SD 0.01) and 0.93 (SD 0.01), and mean accuracies of 0.878 (SD 0.017) and 0.843 (SD 0.015), respectively, for detecting pathological ears on the 2 data sets. Similar outcomes were observed for cholesteatoma identification (mean area under the receiver operating characteristic curve 0.85, SD 0.03 and 0.83, SD 0.05; mean accuracies 0.783, SD 0.04 and 0.813, SD 0.033, respectively). The proposed 3D model achieved a commendable balance between performance and network size relative to alternative models. It significantly outperformed the 2D approach in detecting COM (P≤.05) and exhibited a substantial gain in identifying cholesteatoma (P<.001). The model also demonstrated superior diagnostic capabilities over resident fellows and the attending otologist (P<.05), rivaling all senior clinicians in both tasks. The generated heat maps properly highlighted the middle ear and mastoid regions, aligning with human knowledge in interpreting temporal bone CT. The resulting AI system achieved an accuracy of 81.8% in generating preoperative diagnoses for 121 patients and contributed to clinical decision-making in 90.1% cases. CONCLUSIONS: We present a 3D CNN model trained to detect pathological changes and identify cholesteatoma via temporal bone CT scans. In both tasks, this model significantly outperforms the baseline 2D approach, achieving levels comparable with or surpassing those of human experts. The model also exhibits decent generalizability and enhanced comprehensibility. This AI system facilitates automatic COM assessment and shows promising viability in real-world clinical settings. These findings underscore AI's potential as a valuable aid for clinicians in COM evaluation. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000036300; https://www.chictr.org.cn/showprojEN.html?proj=58685.

Clinical evaluation of temporal bone anatomical abnormalities and surgical method selection in patients with congenital aural atresia.

OBJECTIVES: To analyze anatomic variations of the temporal bone in congenital aural atresia (CAA) and their correlation with the Jahrsdoerfer score, in order to guide clinical selection of surgical treatment methods. MATERIAL AND METHODS: We retrospectively studied 53 patients (72 ears) with unilateral or bilateral CAA, including 34 ears with normal hearing as controls. Audiological and imaging data were collected and analyzed. We evaluated the Jahrsdoerfer score and anatomical variations, including tegmen mastoideum position, anterior sigmoid sinus displacement, and elevated jugular bulb. RESULTS: The average air conduction hearing threshold (PTA4) ranged from 0.5 to 4 kHz was 65.48 ± 8.19 dBHL, with an average Jahrsdoerfer score of 4.93 ± 2.78. In CAA group, there was a higher prevalence and severity of anterior sigmoid sinus and low position of the tegmen mastoideum (P < 0.01). However, there was no significant difference in incidence rates among groups with high jugular bulb (P > 0.05). Anterior sigmoid sinus and high jugular bulb showed no correlation with the Jahrsdoerfer score, while the low position of the tegmen mastoideum had a weak correlation. The Jahrsdoerfer score did not adequately predict temporal bone anatomical abnormalities in CAA patients. CONCLUSION: CAA exhibit a higher incidence and greater severity of temporal bone anatomical abnormalities compared to the control group, and the Jahrsdoerfer score inadequately assesses these abnormalities. Anomalies like low position of the tegmen mastoideum, anterior sigmoid sinus, and high jugular bulb should also be considered as independent factors influencing surgical decisions for atresiaplasty.

Gun shot injuries to the temporal bone: Anatomic predictors of mortality.

PURPOSE: To explore anatomic predictors of mortality from gunshot wounds involving the temporal bone. METHODS: A retrospective search of radiology reports was performed for all patients with CT reports suggestive of gunshot wounds (GSW) to the TB (2000-2020). All cases were reviewed by the senior author to confirm injury to the temporal bone. Detailed demographic and radiographic data were collected. MAIN FINDINGS: A total of 120 patients met inclusion criteria. The majority of patients were male (n = 101) and the average age was 32.9. The squamosa was the most commonly involved subsite (n = 90), followed by the mastoid (n = 43). Squamosal entry site had the highest associated mortality (89.7 %). For those with known disposition, 65.8 % (79 of 120) expired on the same hospital admission. Inpatient otolaryngology consultation was noted in 18.3 % (n = 22) of patients, with poor outpatient follow-up. CONCLUSIONS: This series represents the largest survey of GSW to the temporal bone to date. Although associated mortality is high and outpatient follow-up poor, otolaryngologists should be aware of associated morbidities to facilitate both inpatient and subsequent outpatient management.

3D printed temporal bones for preoperative simulation and planning.

OBJECTIVE: Demonstrate the utility of 3D printed temporal bone models in individual patient preoperative planning and simulation. METHODS: 3D models of the temporal bone were made from 5 pediatric and adult patients at a tertiary academic hospital with challenging surgical anatomy planned for cochlear implantation or exteriorization of cholesteatoma with complex labyrinthine fistula. The 3D models were created from CT scan used for preoperative planning, simulation and intraoperative reference. The utility of models was assessed for ease of segmentation and production and impact on surgery in regard to reducing intraoperative time and costs, improving safety and efficacy. RESULTS: Three patients received cochlear implants, two exteriorization of advanced cholesteatoma with fistulas (1 internal auditory canal/cochlea, 1 all three semicircular canals). Surgical planning and intraoperative referencing to the simulations by the attending surgeon and trainees significantly altered original surgical plans. In a case of X-linked hereditary deafness, optimal angles and rotation maneuvers for cochlear implant insertion reduced operating time by 93 min compared to the previous contralateral side surgery. Two cochlear implant cases planned for subtotal petrosectomy approach due to aberrant anatomy were successfully approached through routine mastoidectomy. The cholesteatoma cases were successfully exteriorized without necessitating partial labyrinthectomy or labyrinthine injury. There were no complications. CONCLUSION: 3D printed models for simulation training, surgical planning and use intraoperatively in temporal bone surgery demonstrated significant benefits in designing approaches, development of patient-specific techniques, avoidance of potential or actual complications encountered in previous or current surgery, and reduced surgical time and costs.

Impact of superior semicircular canal dehiscence on cochlear implant audiologic outcomes.

PURPOSE: Determine whether adult cochlear implant users with radiographic superior semicircular canal dehiscence experience clinically significant differences in audiological outcomes when compared to cochlear implant users with normal temporal bone anatomy. MATERIALS AND METHODS: Retrospective, single institution review. Adult, post-lingual deaf patients implanted between 2010 and 2020. Inclusion criteria included age 18 years or older, available preoperative computed tomography imaging, and preoperative and postoperative AzBio audiological data for at least 6 months of cochlear implant use. Preoperative and postoperative AzBio Sentence Test scores were compared between patients with normal temporal bone anatomy and those with radiographic superior semicircular canal dehiscence or near dehiscence. RESULTS: 110 patients met inclusion criteria. Mean AzBio score for normal temporal bone anatomy group improved from 35.2 % (SD 28.2) preoperatively to 70.3 % (SD 25.7) postoperatively, an improvement of 35.1 % (SD 28.6). Mean AzBio score for near dehiscent temporal bone anatomy group improved from 26.6 % (SD 28.9) preoperatively to 64.5 % (SD 30.6) postoperatively, an improvement of 37.9 % (SD 27.9). Mean AzBio score for dehiscent temporal bone anatomy group improved from 26.3 % (SD 20.4) preoperatively to 65.1 % (SD 27.6) postoperatively, an improvement of 38.7 % (SD 26.9). Utilizing the one-way analysis of variance test, there was no significant difference in audiologic outcomes between the three groups. CONCLUSIONS: Patients with complete or near complete radiographic superior canal dehiscence at the time of cochlear implantation achieve similar improvements in speech perception scores compared to normal anatomy adult cochlear implant users.

Audiometric outcomes following surgery for spontaneous temporal bone cerebrospinal fluid leaks - A single institution study.

PURPOSE: To assess the audiometric outcomes following surgical repair of spontaneous temporal bone cerebrospinal fluid otorrhea and compare different surgical approaches. MATERIALS AND METHODS: Retrospective review of adults (≥18 years old) who underwent repair of spontaneous CSF leak between 2011 and 2022. Audiometric outcomes were compared across the three surgical groups: transmastoid, middle cranial fossa and combined. RESULTS: Thirty-nine patients (40 ears) met the inclusion criteria (71.8 % females; mean age 59.77 +/- 12.4). Forty-two percent underwent transmastoid, 12.5 % middle cranial fossa and 45 % transmastoid-middle cranial fossa. Four patients (10 %) had recurrence, 3 in the transmastoid group and 1 in the combined approach. The mean change in air-bone gap (ABG) for all patients (postoperative-preoperative) was -7.4 (paired t-test, p-value = 0.0003). The postoperative ABG was closed in 28 (70 %) ears (postoperative ABG ≤ 15). The mean change in pure tone average (PTA) for all patients (postoperative-preoperative) was -4.1 (paired t-test, p-value = 0.13). The mean change in word recognition scores (WRS) for all patients (postoperative-preoperative) was -3 (paired t-test, p-value = 0.35). On multivariable analysis (controlling for site and reconstruction material), there was no significant difference in ABG, PTA and WRS change between surgical groups. CONCLUSIONS: Transmastoid, middle cranial fossa and combined approaches are all effective in treatment of spontaneous CSF leaks and all showed mean decrease in post-operative ABG. Transmastoid approach showed the greatest decrease in ABG and PTA (although middle cranial fossa approach shows the greatest decrease, when excluding profound hearing loss in a patient with superior canal dehiscence). Further studies comparing audiometric outcomes are needed.