Temporal bone fractures are divided into otic capsule sparing and otic capsule involving fractures. In the latter, hearing loss, facial nerve paralysis, cerebrospinal fluid leak and meningitis have ...been reported to occur. The impact of hearing loss can be devastating, especially when occurring in children, with significant risk to speech development and sound localization. In the event of hearing loss, early rehabilitation is therefore of paramount importance. Identification of an intra-operative fracture line with available images and the outcome of such cases has not been reported.
We present the case of a 31-month-old male with an otic capsule involving temporal bone fracture, who presented with ipsilateral profound hearing loss. After all required work-up had been performed, he was admitted for a cochlear implant insertion. Per- operatively, a clear fracture line was seen at the round window niche, but a normal insertion was performed despite the anticipated potential ossification at the fracture line. The dreaded complications of cerebrospinal fluid otorrhea or non-auditory stimulation post-implant did not occur. The peculiarity of this case was its rarity, which was demonstrated by clear images that showed the fracture line on preoperative imaging and intraoperatively.
Cochlear implantation in the presence of a visible fracture line is feasible and the surgical procedure must not be aborted at its discovery. In these cases, post-operative bacterial meningitis can occur and should be treated aggressively with systemic antibiotics to avoid contralateral ossification of the labyrinth due to labyrinthitis.
Temporal Bone Histology and Radiology Atlas provides a user-friendly approach to understanding both microscopic and radiographic anatomy of the temporal bone. It examines horizontal and vertical ...histologic sections and correlates them to the more commonly seen radiographic images, primarily on CT and also on MR.
The aim of this project was to investigate the effects of different types of graft material, and different remaining segments of the native TM on its motion. In twelve human temporal bones, ...controlled TM perforations were made to simulate three different conditions. (1) Central perforation leaving both annular and umbo rims of native TM. (2) Central perforation leaving only a malleal rim of native TM. (3) Central perforation leaving only an annular rim of native TM. Five different graft materials (1) perichondrium (2) silastic (3) thin cartilage (4) thick cartilage (5) Lotriderm® cream were used to reconstruct each perforation condition. Umbo and stapes vibrations to acoustic stimuli from 250 to 6349 Hz were measured using a scanning laser Doppler vibrometer. Results showed that at low frequencies: in the Two Rims condition, all grafting materials except thick cartilage and Lotriderm cream showed no significant difference in umbo velocity from the Normal TM, while only Lotriderm cream showed a significant decrease in stapes velocity; in the Malleal Rim condition, all materials showed a significant decrease in both umbo and stapes velocities; in the Annular Rim condition, all grafting materials except Lotriderm and perichondrium showed no significant difference from the Normal TM in stapes velocity. Umbo data might not be reliable in some conditions because of coverage by the graft. At middle and high frequencies: all materials showed a significant difference from the Normal TM in both umbo and stapes velocities for all perforation conditions except in the Annular Rim condition, in which silastic and perichondrium showed no significant difference from the Normal TM at umbo velocity in the middle frequencies. In the low frequencies, the choice of repair material does not seem to have a large effect on sound transfer. Our data also suggests that the annular rim could be important for low frequency sound transfer.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Trauma to the osseous spiral lamina (OSL) or spiral ligament (SL) during cochlear implant (CI) insertion segregates with electrode type and induces localized intracochlear ossification and fibrosis.
...The goal of atraumatic CI insertion is to preserve intracochlear structures, limit reactive intracochlear tissue formation, and preserve residual hearing. Previous qualitative studies hypothesized a localized effect of trauma on intracochlear tissue formation; however, quantitative studies failed to confirm this.
Insertional trauma beyond the immediate insertion site was histologically assessed in 21 human temporal bones with a CI. Three-dimensional reconstructions were generated and virtually resectioned perpendicular to the cochlear spiral at high resolution. The cochlear volume occupied by ossification or fibrosis was determined at the midpoint of the trauma and compared with regions proximal and distal to this point.
Seven cases, all implanted with precurved electrodes, showed an OSL fracture beyond the immediate insertion site. Significantly more intracochlear ossification was observed at the midpoint of the OSL fracture, compared with the -26 to -18 degrees proximal and 28 to 56 degrees distal to the center. No such pattern was observed for fibrosis. In the 12 cases with a perforation of the SL (9 straight and 3 precurved electrodes), no localized pattern of ossification or fibrosis was observed around these perforations.
OSL fractures were observed exclusively with precurved electrodes in this study and may serve as a nidus for localized intracochlear ossification. Perforation of the SL, in contrast, predominantly occurred with straight electrodes and was not associated with localized ossification.
Recent animal work has suggested that cochlear synapses are more vulnerable than hair cells in both noise-induced and age-related hearing loss. This synaptopathy is invisible in conventional ...histopathological analysis, because cochlear nerve cell bodies in the spiral ganglion survive for years, and synaptic analysis requires special immunostaining or serial-section electron microscopy. Here, we show that the same quadruple-immunostaining protocols that allow synaptic counts, hair cell counts, neuronal counts and differentiation of afferent and efferent fibers in mouse can be applied to human temporal bones, when harvested within 9 h post-mortem and prepared as dissected whole mounts of the sensory epithelium and osseous spiral lamina. Quantitative analysis of five “normal” ears, aged 54–89 yrs, without any history of otologic disease, suggests that cochlear synaptopathy and the degeneration of cochlear nerve peripheral axons, despite a near-normal hair cell population, may be an important component of human presbycusis. Although primary cochlear nerve degeneration is not expected to affect audiometric thresholds, it may be key to problems with hearing in noise that are characteristic of declining hearing abilities in the aging ear.
•Human temporal bones were immunostained and examined by confocal microscopy.•“Normal” ears from 54 to 89 yrs with no history of otologic disease were selected.•Hair cells, synaptic ribbons, cochlear nerve axons and efferent axons were counted.•Results showed cochlear neurodegeneration without hair cell loss in the oldest ears.•Results suggest that primary neural degeneration is important in human presbycusis.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
A 7-month-old female Holstein calf presented with bilateral microtia and absent external acoustic meatus. The real-time polymerase chain reaction test was negative for bovine viral diarrhea virus and ...bovine leukemia virus. The calf’s dam had a normal reproductive history. Computed tomography confirmed bilateral atresia of external auditory canals, aplasia of tympanic cavities and the ossicular chain, and temporomandibular joint abnormality. Necropsy revealed a severe malformation of the temporal bone. In the tympanic region, the external acoustic pore, tympanic bulla, and muscular process were absent bilaterally. The bilateral inner ear structure was normal. Based on these findings, we diagnosed the present case as congenital malformations of the external and middle ear accompanied by temporal bone anomaly.
The purpose of this study was to investigate the efficacy of otic capsule-sparing (OCS) length for the prediction of sensorineural hearing loss (SNHL) in patients with OCS temporal bone fracture.
...Thirty-four patients with OCS temporal bone fracture were enrolled, and their temporal bone computed tomography (TBCT), audiogram, and medical records were reviewed. The TBCT measured the shortest length between the otic capsule and fracture line. This length was referred to as the OCS length and was used to predict SNHL. Ossicular dislocation and fracture were also evaluated. Patients were divided into two groups according to the presence of SNHL. Univariate and multivariate analyses were performed for age, gender, brain hemorrhage, mean bone conduction threshold on the contralesional side, OCS length, and ossicular dislocation and fracture on TBCT. A receiver operating characteristic (ROC) curve was produced to evaluate the efficacy of OCS length for the prediction of SNHL. To determine an association between degree of SNHL and OCS length, regression analysis was conducted in the SNHL group.
The mean OCS lengths of the SNHL and non-SNHL groups were 4.42±1.67mm and 8.00±5.71mm, respectively. In the univariate analysis, a relatively significant association (P <0.20) was found between SNHL and age, brain hemorrhage, mean bone conduction threshold on the contralesional side, OCS length, and incus dislocation. Multivariate analysis was performed using these factors. On multivariate analysis, OCS length (P=0.030, odds ratio=0.598; 95% confidence interval 0.375–0.952) was the only independent factor associated with SNHL. The area under the curve (AUC) was 0.747. When the cut-off value of OCS length was 5.27mm, the sensitivity and specificity for the prediction of SNHL were 71.4% and 69.2%, respectively. In the regression analysis, OCS length showed a significant association with degree of SNHL in the SNHL group (P=0.025, β=-12.822, SE=5.282).
The major finding of our study was that OCS length was significantly associated with SNHL in patients with OCS temporal bone fracture. Such patients with a short OCS length had a higher likelihood of SNHL.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK, ZRSKP
Objectives
To develop a novel grading system and appropriate surgical approaches for patients with diffuse type tensosynovial giant cell tumor (D‐TGCT) of the temporal bone.
Study Design
...Retrospective cohort study.
Methods
We retrospectively reviewed 31 patients with temporal bone D‐TGCT between June 2012 and July 2021. All patients underwent comprehensive clinical evaluations, including clinical presentations, hearing threshold, imaging studies, surgical approaches, and prognosis. A grading system was developed based on the tumor location and adjacent neurovascular structures involvement according to imaging and intraoperative findings.
Results
In this study, grade II tumors were the most common (13/31), followed by grades I (7/31), III (7/31), and IV (4/31) tumors. Seven grade I patients received the subtemporal middle cranial fossa approach (SMCF) combined with the canal wall up mastoidectomy and tympanoplasty (CWUT). Nine grade II patients underwent SMCF combined with subtotal petrosectomy (SPTR), and four grade II patients underwent SMCF combined with CWUT. Seven grade III patients received SMCF combined with SPTR and dura mater reconstruction, and four grade IV patients underwent infratemporal fossa approach type B. Gross total resection was achieved in all patients, and the median follow‐up time was 30.1 months (range, 4–96 months). Three patients (one grade II, one grade III, and one grade IV) had recurrence during follow‐up, and the patient with grade III tumor had two recurrences.
Conclusions
Gross total resection is the first‐line treatment for patients with D‐TGCT of the temporal bone. This novel grading system enables surgeons to select optimal surgical strategy. Long‐term follow‐up is mandatory postoperatively.
Level of Evidence
4 Laryngoscope, 132:1275–1284, 2022
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Objectives/Hypothesis
To describe the histopathology of the invasion patterns of advanced‐stage external auditory canal (EAC) squamous cell carcinoma (SCC).
Study Design
Retrospective cohort study.
...Methods
Retrospective analysis of medical records of patients diagnosed with EAC SCC available at the Massachusetts Eye and Ear temporal bone (TB) collection. TBs underwent processing for histologic examination. Hematoxylin and eosin–stained slides were examined. Histologic findings were compared to premortem clinical data.
Results
Nine TBs were identified. Male:female ratio was 6:3. The average age of diagnosis and duration of survival was 64 (46–80 years) and 2.3 years (1–50 months), respectively. All presented with T4 disease, most commonly due to petrous apex (PA) invasion and facial nerve (FN) weakness. The mastoid air cells system served as a tumor conduit to the tegmen mastoideum and overlying dura in four patients, posterior fossa dura in one patient, vertical segment of FN in four patients, and middle ear (ME) and lateral semicircular canal in five patients. The tumor did not penetrate the tympanic membrane, oval window membrane (fenestra vestibule), or round window (RW) membrane. Supra‐ and infralabyrinthine pneumatization patterns allowed direct routes to the PA. Translabyrinthine PA invasion was seen in two patients. The most common locus of otic capsule invasion was the cochlea. One patient had FN paralysis due to compression rather than invasion.
Conclusions
SCC does not tend to extend from the ME to the inner ear through the RW and vestibule‐stapedial ligament. Tumors tend to spread along the preexisting TB air‐tract routes. Well‐aerated TB, may facilitate extension to the PA.
Level of Evidence
4 Laryngoscope, 131:E590–E597, 2021
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
PDF
