Temporal bone fractures

Improved Prediction of Hearing Loss after Temporal Bone Fracture by Applying a Detailed Classification for Otic Capsule-Violating Fracture: A Wide Scope Analysis with Large Case Series

INTRODUCTION

This study aimed to analyze the predictability of temporal bone (TB) fracture-associated hearing loss by applying a detailed classification separating individual injury of the cochlea, vestibule, and semicircular canals (SCC).

METHODS

In this retrospective study, patients with otic capsule-violating (OCV) fractures were further classified as OCV-C(VS) when the cochlea was involved regardless of vestibule or SCC involvement, OCV-V(S) when the vestibule was involved regardless of SCC involvement, and OCV-S when the fracture only involved SCC. Hearing changes were compared by applying the above-mentioned classification, and TB fracture-induced facial palsy was also analyzed.

RESULTS

A total of 119 patients were included. Patients with OCV fractures had significantly worse bone conduction (BC) and air conduction (AC) thresholds (59.1 ± 25.3 and 87.0 ± 29.5 dB) than those with otic capsule-sparing (OCS) fractures (20.1 ± 17.9 and 36.5 ± 21.9 dB; p < 0.001 for each comparison). The BC and the AC thresholds of OCV-C(VS) (77.5 ± 11.0 and 114.2 ± 14.3 dB) and OCV-V(S) (69.3 ± 27.7 and 98.0 ± 22.2 dB) were significantly higher than OCV-S (40.1 ± 22.9 and 62.1 ± 25.6 dB; p < 0.001 for each comparison). The BC hearing thresholds were not significantly improved in the last pure tone audiometry when compared for total, OCV, or OCS cases. The AC threshold significantly improved in OCS cases. In a considerable number of cases with facial palsy, causative fracture lines involved the geniculate ganglion or tympanic segment without the involvement of the otic capsule. Most cases showed significant improvement; however, recovery was limited in cases with obvious fallopian canal disruption.

CONCLUSIONS

The cases with sole involvement of SCC had significantly better hearing thresholds than those with cochlear or vestibule involvement, even in OCV fracture cases.

Incidence and Management of Facial Paralysis After Skull Base Trauma, an Administrative Database Study

OBJECTIVE

Report the incidence of and treatment patterns for facial nerve palsy after skull base fracture.

STUDY DESIGN

Retrospective cohort study.

SETTING

IBM MarketScan Commercial Database (2006-2019).

PATIENTS

Human subjects with skull base fracture, per International Classification of Diseases-9th and 10th Revisions-Clinical Modification diagnosis codes.

MAIN OUTCOME MEASURES

The primary outcomes were the incidence and median time to facial nerve palsy diagnosis within 30 days of skull base fracture. Secondary outcomes were treatments (corticosteroids, antivirals, facial nerve decompression, botulinum toxin, and facial reanimation), demographics, and rates of hearing loss, vertigo, tympanic membrane rupture, cerebrospinal fluid leak, comorbidities, and loss of consciousness.

RESULTS

The 30-day incidence of facial nerve palsy after skull base trauma was 1.0% (738 of 72,273 patients). The median (95% confidence interval [CI]) time to diagnosis was 6 (6-7) days, and only 22.9% were diagnosed within 1 day. There were significantly higher rates (risk difference, 95% CI) of hearing loss (26%, 22-29%), tympanic membrane rupture (6.3%, 4.5-8.1%), cerebrospinal fluid leak (6.4%, 4.5-8.3%), comorbidity (14%, 10.4-17.6%), and loss of consciousness (24.3%, 20.7-27.9%). Loss of consciousness was associated with longer median (95% CI) time to facial nerve palsy diagnosis: 10 (9-10) days. Corticosteroids were the most common treatment but only reported for less than one-third of patients. Only eight patients underwent facial nerve decompression.

CONCLUSIONS

Facial nerve palsy after skull base fracture is associated with higher comorbidity, and the diagnosis is often delayed. Few patients were treated with surgery, and there are inconsistencies in the types and timing of treatments.

Otological Assessment in Head Injury Patients: A Prospective Study and Review of Literature

Head injuries constitute a tragic problem invariably in under-developed, developed and developing countries. The concomitant otological injuries often go unnoticed. The purpose of this study was to assess the various otological manifestations following head injuries. Prospective study with review of literature using PubMed database was done. All the patients were evaluated for their presenting symptoms and signs. Audiological investigations including PTA (Pure tone audiometry), OAE (Otoacoustic emission), Impedance-Audiometry and BERA were done. HRCT temporal bone was advised in cases of suspicion. Relevant literature was reviewed to calculate the pooled prevalence rates. Random-effects model to synthesize overall effects was used. Heterogeneity was evaluated with the I² statistic. Of 53 patients enrolled in the study, RTA was the most common mode of injury. The audiometric findings showed SNHL, CHL and mixed HL in 34, 20 and 18% of patients respectively. HRCT showed Longitudinal fracture (n = 17; 53.12%); isolated mastoid bone fracture (n = 9; 28.12%), transverse (n = 3; 9.37%) and isolated EAC fracture in (n = 3; 9.37%) patients. The pooled prevalence (n = 1106 patients) of SNHL, CHL, Mixed HL and Normal hearing were-35% (95%CI, 18-55%; I² = 95.20%; P < 0.00), 24% (95%CI, 16-33%; I² = 80.01%; P < 0.00), 15%(95%CI, 9-23%; I² = 79.64%; P < 0.00) and 30% (95%CI, 3-66%; I² = 98.71%; P < 0.00) respectively. The pooled prevalence (n = 4191 patients) of longitudinal, Transverse, mixed and other fractures were-44% (95%CI, 3-66%;I² = 99.48%; P < 0.00), 9% (95% CI, 4-16%; I² = 95.95%; P < 0.00), 4% (95%CI, 1-8%; I² = 94.13%; P < 0.00) and 1% (95%CI, 0-4%; I² = 90.37%; P < 0.00) respectively. In patients with head injury coordination between the trauma-surgeon, neurosurgeon and otologist is must to improve the long-term outcomes.

Traumatic temporal bone fracture with middle ear effusion: A case report

Temporal bone fracture is a relatively rare but significant complication of traumatic head injury. We present a rare and unique case of traumatic temporal bone fracture with middle ear effusion, in a 76-year-old woman, following a fall. Physical examination on presentation was remarkable for a superficial scalp hematoma in the occipital region, without any focal neurological deficits. An initial non-contrast head CT revealed a large posterior scalp hematoma and subtle changes suggestive of artifact vs. hemorrhage within the right temporal lobe. Over two days, she developed a worsening headache, with new hearing impairment and reduced right sided bone-conduction on auditory testing. A repeat head CT confirmed a right hemorrhagic temporal lobe contusion as well as a right mastoid and middle ear effusion. A dedicated temporal bone CT scan was performed, which revealed an acute longitudinal fracture through the right mastoid bone without extension into the middle ear cavity. She was evaluated by neurosurgery, managed symptomatically, and observed closely. Her neurological status remained stable, and she was discharged with planned outpatient follow-up with her primary care provider and the consulting neurosurgeon. This case illustrates sequalae of traumatic temporal bone fracture, as well as the value of clinical history and heightened clinical concern for an occult, easily overlooked region during imaging.

Neuroimaging of Dizziness and Vertigo

Dizziness and vertigo are common symptoms in the primary care and emergency settings, resulting in a significant decrease in quality of life and a high cost burden to the US health care system. The etiology of these symptoms is difficult to elucidate owing to a wide range of diseases with overlapping manifestations. The broad differential diagnosis based on whether the disease process is central or peripheral is showcased. Each differential will be categorized into neoplastic, infectious or inflammatory, structural, traumatic, and iatrogenic causes. Computed tomography scans, MRI, and vascular imaging are frequently complimentary in providing diagnoses and guidance in management.

Long-term cochlear implantation outcomes in patients following head injury

OBJECTIVE

In cases of a severe to profound sensorineural hearing loss following head injury, the cochlear implant (CI) is the primary option for auditory rehabilitation. Few studies, however, have investigated long-term CI outcomes in patients following head trauma, including those without temporal bone fracture (TBF). Herein, the aim of this study is to examine CI outcomes following cases of head injury with and without TBF.

METHODS

Audiometric outcomes of patients who received a CI due to a head injury resulting in severe to profound hearing loss at two tertiary care hospitals were analyzed. Patients were divided into those who received a CI in a fractured temporal bone (group A, n = 11 patients corresponding to 15 ears) and those who received a CI in a non-fractured temporal bone (group B, n = 8 patients corresponding to nine ears). Primary outcomes included duration of deafness prior to CI and postoperative consonant-nucleus-constant whole word (CNC) scores.

RESULTS

Nineteen patients (84% male), corresponding to 24 CIs, were identified. Fifteen CI were performed on ears with TBF (group A), and nine CI were performed on ears without TBF (group B). No patients had an enlarged vestibular aqueduct (EVA). The mean duration of deafness was 5.7 and 11.3 years in group A and group B, respectively. The mean duration of CI follow-up (CI experience) was 6.5 years in group A and 2.1 years in group B. The overall mean postoperative CNC score for all subjects was 68.6% (±21.2%, n = 19 with CNC testing). There was no difference in CNC score between group A and group B (69.8% and 66% respectively, P = .639).

CONCLUSION

The study is among the largest series examining long-term outcomes of CI after head injury. CI is an effective method for auditory rehabilitation in patients after head injury.

LEVEL OF EVIDENCE

IV.

Peripheral Vestibular Organ Degeneration After Temporal Bone Fracture: A Human Otopathology Study

OBJECTIVES/HYPOTHESIS

Vestibular symptoms are a common sequela of temporal bone fractures (TBFs). The mechanisms of injury to the peripheral vestibular system following TBF, however, are not well described. Herein, we aimed to investigate the histopathology of the peripheral vestibular system in patients who sustained TBFs.

STUDY DESIGN

Retrospective human specimen analysis.

METHODS

Specimens from the National Temporal Bone Pathology Registry with (cases) and without (controls) TBFs were evaluated. Specimens were analyzed by light microscopy for vestibular hair cell and/or dendritic degeneration, presence of endolymphatic hydrops, blockage of the endolymphatic duct, and number of Scarpa ganglion cells (ScGCs) in the superior and inferior vestibular nerves.

RESULTS

Seven temporal bones (TBs) from five individuals with TBFs, and seven TBs from six age-matched individuals without a history of head injury met inclusion and exclusion criteria. All fractures involved the otic capsule. Severe degeneration of the cristae was identified in the semicircular canals in all TBF cases. The utricular and saccular maculae showed mild to severe degeneration in the TBF cases. Vestibular hydrops (n = 2 TBs) and blockage of the endolymphatic duct (n = 3 TBs) were also present in the TBF cases. There was a decrease of 52.6% in the mean total ScGC count in the TBF cases (n = 3 TBs) compared to age-matched controls (n = 7 TBs, P = .015). There was a mean loss of 53% of the ScGCs in the superior vestibular nerve and a mean loss of 52.3% of the ScGCs in the inferior vestibular nerve compared to age-matched controls (P = .033 and P = .021, respectively).

CONCLUSIONS

In a cohort of patients with TBFs, there were distinct peripheral vestibular changes including reduction of ScGCs.

LEVEL OF EVIDENCE

NA Laryngoscope, 130:752-760, 2020.

Temporal bone trauma effects on auditory anatomical structures in mastoid obliteration

PURPOSE

The risk of temporal bone fractures in head trauma is not negligible, as injuries also depend on the resistance and integrity of head structures. The capacity of mastoid cells to absorb part of the impact kinetic energy of the temporal bone is diminished after open cavity mastoidectomy, even if the surgical procedure is followed by mastoid obliteration. The aim of our study was to evaluate the severity of lesions in auditory anatomical structures after a lateral impact on cadaveric temporal bones in which open cavity mastoidectomy followed by mastoid obliteration was performed, compared to cadaveric temporal bones with preserved mastoids.

METHODS

The study was carried out on 20 cadaveric temporal bones, which were randomly assigned to two groups. In the study group, open cavity mastoidectomy followed by mastoid obliteration with heterologous materials was performed. All temporal bones were impacted laterally under the same conditions. Temporal bone fractures were evaluated by CT scan.

RESULTS

External auditory canal fractures were six times more seen in the study group. Tympanic bone fractures were present in 80% of the samples in the study group and 10% in the control group (p = .005). Middle ear fractures were found in 70% of the samples in the study group and 10% in the control group (p = .02). Otic capsule violating fractures of the temporal bone were present only in the study group.

CONCLUSIONS

Mastoid obliteration with heterologous materials after open cavity mastoidectomy increases the risk of fracture, with the involvement of auditory anatomical structures.

Cross Sectional Imaging of the Ear and Temporal Bone

CT and MR imaging are essential cross-sectional imaging modalities for assessment of temporal bone anatomy and pathology. The choice of CT versus MR depends on the structures and the disease processes that require assessment, delineation, and characterization. A thorough knowledge of the two imaging modalities' capabilities and of temporal bone anatomy greatly facilitates imaging interpretation of pathologic conditions.

Hearing loss in pediatric temporal bone fractures: Evaluating two radiographic classification systems as prognosticators

INTRODUCTION

Temporal bone fractures (TBF) are traditionally classified by their angle of fracture relative to the petrous ridge, and more recently by whether or not they violate the otic-capsule. This study compared rates of hearing loss (HL) and signs of otologic dysfunction among fracture types of both classification systems, within the pediatric population.

METHODS

Pediatric patients were retrospectively characterized from a previously identified cohort of TBF patients, diagnosed from 2000 to 2014. CT scans were reviewed and TBFs were classified first as longitudinal (L), transverse (T) or mixed (M), and then as otic-capsule sparing (OCS) or otic-capsule violating (OCV). Medical records were reviewed, and rates of HL and presenting signs were compared among L, T and M fractures, and OCS and OCV fractures.

RESULTS

Forty-three patients with 47 TBFs met the inclusion criteria. Eighteen, 4 and 25 TBFs were classified as L, T and M fractures, respectively. Thirty-three and 9 were classified as OCS, and OCV, respectively. Among 24 cases of HL: 20, 3, and 1 were conductive HL (CHL), sensorineural HL (SNHL) and mixed HL, respectively. Two cases of SNHL were found among OCV fractures, with none in OCS fractures (estimated difference 0.22; 95% confidence interval 0.01-0.60). Similar rates of CHL were found across L, T and M fractures (range 36-50%), and across OCV and OCS fractures (range 42-44%). Hemotympanum was the most common presenting sign, found in 68% of TBFs and 80% of CHL cases. There were no significant differences in the incidence of signs or symptoms between fracture types.

CONCLUSIONS

In our cohort, both the traditional and otic-capsule radiographic classification systems failed to predict the incidence of CHL and other otologic signs in the pediatric population. Though OCV fractures conferred an increased risk for developing SNHL, we found a lower incidence than anticipated given violation to the bony labyrinth.

Using temporal bone computed tomography to predict sensorineural hearing loss in otic capsule-sparing temporal bone fracture

OBJECTIVES

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Hearing and Mortality Outcomes following Temporal Bone Fractures

The aim of this article is to determine hearing and mortality outcomes following temporal bone fractures. Retrospective chart review was performed of 152 patients diagnosed with a temporal bone fracture presenting to the emergency room at a tertiary care referral center over a 10-year period. Utilizing Patients' previously obtained temporal bone computed tomographic scans and audiograms, fractures were classified based on several classification schemes. Correlations between fracture patterns, mortality, and hearing outcomes were analyzed using χ² tests. Ossicular chain disruption was seen in 11.8% of patients, and otic capsule violation was seen in 5.9%; 22.7% of patients presented for audiologic follow-up. Seventeen patients with conductive hearing loss had air-bone gaps of 26 ± 7.5 dB (500 Hz), 27 ± 6.8 dB (1,000 Hz), 18 ± 6.2 dB (2,000 Hz), and 32 ± 7.7 dB (4,000 Hz). Two cases of profound sensorineural hearing loss were associated with otic capsule violation. No fracture classification scheme was predictive of hearing loss, although longitudinal fractures were statistically associated with ossicular chain disruption ( p  < 0.01). Temporal bone fractures in patients older than 60 years carried a relative risk of death of 3.15 compared with those younger than 60 years. The average magnitude of conductive hearing loss resulting from temporal bone fracture ranged from 18 to 32 dB in this cohort. Classification of fracture type was not predictive of hearing loss, despite the statistical association between ossicular chain disruption and longitudinal fractures. This finding may be due to the low follow-up rates of this patient population. Physicians should make a concerted effort to ensure that audiological monitoring is executed to prevent and manage long-term hearing impairment.

Clinical features and radiological evaluation of otic capsule sparing temporal bone fractures

Objective:

To evaluate the clinical and radiological aspects of otic capsule sparing temporal bone fractures.

Methods:

Using medical records, 188 temporal bones of 173 patients with otic capsule sparing temporal bone fractures were evaluated. Otoscopic findings and symptoms, facial paralysis, and hearing loss were assessed.

Results:

Using regional analysis, 7 fractures were classified as type I, 85 as type II, 169 as type III and 114 as type IV. Fourteen of the 17 facial paralysis cases improved to House–Brackmann grade II or lower at an average of 57.6 days after the initial evaluation. Thirty-one patients underwent initial and follow-up pure tone audiometry examinations. The air–bone gap closed significantly from 27.2 dB at an average of 21.8 days post-trauma to 19.6 dB at an average of 79.9 days post-trauma, without the need for surgical intervention.

Conclusion:

Initial conservative treatment for facial paralysis or conductive hearing loss is possible in otic capsule sparing fracture cases after careful evaluation of the patient.

Temporal bone fracture: Evaluation in the era of modern computed tomography

BACKGROUND

Temporal bone fractures (TBFs) are harbingers of high energy head trauma that can result in a variety of significant complications of the auditory, vestibular, nervous, and vascular systems. Multiple cohort studies have identified the incidence and proper evaluation of these fractures. We hypothesize that these have changed with the advent of modern high resolution computer tomography (CT) imaging.

METHODS

We performed a retrospective review of all TBFs admitted to an urban level one trauma center between June 1, 2011 and May 31, 2015. A database was compiled including demographics, physical exam findings, imaging performed and results, morphology and directionality of fracture as well as outcomes and follow-up.

RESULTS

One hundred thirteen patients were identified, representing 4.7% of skull fractures and 35.9% of skull base fractures. Most were subsequent to falls (41.6%) followed by pedestrian vehicular trauma (19.5%). The majority of TBF patients (67.3%) had additional fractures of the skull and 77.9% of TBF patients also had some kind of intracranial hemorrhage. The morphology of TBF and the overall mortality (7.9%) was consistent with previous reports. The incidence of facial nerve paralysis (1.6%), CSF leak (1.7%), and hearing loss (18.6%) were all lower than previously reported. Trauma imaging was able to identify 98.6% of TBF, calling the utility of routine temporal bone CT imaging into question.

CONCLUSION

TBFs are less common than they once were and though they still carry a mortality rate similar to previously reported cohorts, the incidence of complications among survivors has dramatically improved. Additionally, modern CT imaging is very capable of identifying these injuries and dedicated temporal bone CT may only be of utility in cases where facial nerve injury or vascular injury is suspected.

LEVEL OF EVIDENCE

Epidemiologic study, Level III.

Imaging Review of the Temporal Bone: Part II. Traumatic, Postoperative, and Noninflammatory Nonneoplastic Conditions

The first part of this review of the temporal bone discussed anatomy of the temporal bone as well as inflammatory and neoplastic processes in the temporal bone region (1). This second part will first discuss trauma to the temporal bone and posttraumatic complications. The indications for common surgical procedures performed in the temporal bone and their postoperative imaging appearance are then presented. Finally, a few noninflammatory nonneoplastic entities involving the temporal bone are reviewed. They are relatively uncommon diagnoses compared with infectious or inflammatory diseases. However, because patients present with symptoms that are either common (hearing loss) or distinctive (sensorineural hearing loss in a child), they are important for the radiologist to be aware of and recognize.

Tympanic plate fractures in temporal bone trauma: prevalence and associated injuries

BACKGROUND AND PURPOSE

The prevalence of tympanic plate fractures, which are associated with an increased risk of external auditory canal stenosis following temporal bone trauma, is unknown. A review of posttraumatic high-resolution CT temporal bone examinations was performed to determine the prevalence of tympanic plate fractures and to identify any associated temporal bone injuries.

MATERIALS AND METHODS

A retrospective review was performed to evaluate patients with head trauma who underwent emergent high-resolution CT examinations of the temporal bone from July 2006 to March 2012. Fractures were identified and assessed for orientation; involvement of the tympanic plate, scutum, bony labyrinth, facial nerve canal, and temporomandibular joint; and ossicular chain disruption.

RESULTS

Thirty-nine patients (41.3 ± 17.2 years of age) had a total of 46 temporal bone fractures (7 bilateral). Tympanic plate fractures were identified in 27 (58.7%) of these 46 fractures. Ossicular disruption occurred in 17 (37.0%). Fractures involving the scutum occurred in 25 (54.4%). None of the 46 fractured temporal bones had a mandibular condyle dislocation or fracture. Of the 27 cases of tympanic plate fractures, 14 (51.8%) had ossicular disruption (P = .016) and 18 (66.6%) had a fracture of the scutum (P = .044). Temporomandibular joint gas was seen in 15 (33%) but was not statistically associated with tympanic plate fracture (P = .21).

CONCLUSIONS

Tympanic plate fractures are commonly seen on high-resolution CT performed for evaluation of temporal bone trauma. It is important to recognize these fractures to avoid the preventable complication of external auditory canal stenosis and the potential for conductive hearing loss due to a fracture involving the scutum or ossicular chain.

Geniculate ganglion decompression of facial nerve by transmastoid-epitympanum approach

CONCLUSIONS

We consider that the transmastoid-epitympanum approach to decompression of the geniculate ganglion, without a craniotomy, combining the advantages of middle cranial fossa and transmastoid extralabyrinthine approaches, is simple, minimally invasive, safe, and effective, with little postoperative hearing change. It can be employed in some cases of facial palsy due to temporal bone fracture (TBF) and middle ear cholesteatoma (MEC) in accordance with the range of facial paralysis, facial nerve electrophysiology, and imaging guidance.

OBJECTIVE

To evaluate the efficacy of geniculate ganglion decompression of the facial nerve by the transmastoid-epitympanum approach.

METHODS

Thirty cases of facial palsy were reviewed, including patients with TBF and MEC. All the patients were evaluated by routine preoperative tests including high-resolution computed tomography (HRCT), audiometry, and electroneuronography, and were treated by transmastoid-epitympanum decompression. The negative effects on auditory function were recorded.

RESULTS

The mean percentage facial function improvement (House-Brackmann grade I-II) was 88% in TBF and 100% in MEC. The negative effects on auditory function were less than 10 dB in most cases.

Trauma dos ossos temporais e suas complicações: aspectos na tomografia computadorizada

A maioria das fraturas dos ossos temporais resulta de traumas cranianos bruscos, de alta energia, estando muitas vezes relacionadas a outras fraturas cranianas ou a politraumatismo. As fraturas e os deslocamentos da cadeia ossicular, na orelha média, representam umas das principais complicações das injúrias nos ossos temporais e, por isso, serão abordadas de maneira mais profunda neste artigo. Os outros tipos de injúrias englobam as fraturas labirínticas, fístula dural, paralisia facial e extensão da linha de fratura ao canal carotídeo. A tomografia computadorizada tem papel fundamental na avaliação inicial dos pacientes politraumatizados, pois é capaz de identificar injúrias em importantes estruturas que podem causar graves complicações, como perda auditiva de condução ou neurossensorial, tonturas e disfunções do equilíbrio, fístulas perilinfáticas, paralisia do nervo facial, lesões vasculares, entre outras.

Traumatic Acute Brain Herniation through the Ear in a Child: Concealed compound fracture

A seven-year-old girl presented to Sultan Qaboos University Hospital, Oman, with a history of having been hit by a motor vehicle. After this, she had right-sided cerebrospinal fluid otorrhoea, and a week later, brain matter extruded through the right ear. A computed tomography scan of the brain demonstrated a tegmen fracture communicating with the external auditory canal. There was no hearing or facial nerve impairment and an otoscopic examination showed an intact tympanic membrane. She underwent a transcranial repair of the middle cranial fossa base, which revealed a wide dural and bony defect of the tegmen with herniation of the temporal lobe. Repair was made with an intradural patch of artificial dura. The rarity of this type of presentation of temporal bone fracture and its management are discussed.

Enlarged geniculate ganglion fossa: CT sign of facial nerve canal fracture

RATIONALE AND OBJECTIVES

The aim of this study was to preliminarily investigate whether an enlarged geniculate ganglion fossa (GGF) on temporal bone computed tomography can diagnose GGF fracture in patients with traumatic facial paralysis by evaluating the diameter of the GGF.

MATERIALS AND METHODS

Thirty-six patients who underwent computed tomography before confirmation of GGF fracture on otologic surgery were recruited into a study group. Additionally, a cohort of 107 patients with no histories of head trauma, no structural abnormalities of inner ear, and no clinical symptoms of facial nerve disability who underwent computed tomography for other reasons were selected as a control group. The diameters of the GGFs of the study group were evaluated by two observers and compared retrospectively with those of the control group. Wilcoxon's test was used to compare discrepancies of both sides, and intraclass correlation coefficients were used to evaluate intraobserver and interobserver reliability.

RESULTS

The measurement of diameters showed good interobserver and intraobserver consistency. The discrepancy in the measurement of transdiameter between both sides of the GGF on reformatted transverse images of the study group was significantly different from that of the control group (Wilcoxon's test, P < .001). Discrepancy in the GGF on transverse images of the study group was larger than that of the control group. A significant difference existed in the discrepancy in vertical diameter between the study and control groups (Wilcoxon's test, P < .001) as well.

CONCLUSIONS

An enlarged GGF on temporal bone computed tomography offers an additional sign for the diagnosis of GGF fracture in patients with traumatic facial paralysis.

Clinical Feasibility of Multiplanar Reconstruction Images of Temporal Bone CT in the Diagnosis of Temporal Bone Fracture with Otic-Capsule-Sparing Facial Nerve Paralysis

The aim of this study is to evaluate the feasibility of multiplanar reconstructive (MPR) imaging of temporal bone CT in the diagnosis of temporal bone fracture with oticcapsule-sparing facial nerve paralysis. Twelve patients with traumatic facial nerve paralysis with otic-capsule sparing and temporal bone fractures were selected. Multiplanar reconstruction images were obtained with the V-works 4.0 software program (Cybermed, Seoul, Korea) using axial scanning of high-resolution temporal bone CT of the fracture line. The clinical profiles of the patients displaying temporal bone fractures were examined in relation to the findings. Multiplanar images of the fracture line provided information regarding the direction of the external force that fractured the temporal bone. The fracture line was more continuous in the MPR images than in the axial view. All patients showed an imaginary extended fracture line directed toward the otic capsule. The direction of the fracture line toward the middle ear cavity is important, as it may suggest insult to the otic capsule. The MPR image parallel to the fracture line of the temporal bone provides a guideline for the vector of the force that induced the fracture. Thorough investigation of the critical organs during surgical exploration is recommended if the direction of the fracture in the MPR image points toward the otic capsule in the middle ear even if the fracture line relative to the otic capsule is not well defined in the axial or CT view.

Patterns of intracranial hemorrhage in petrous temporal bone fracture

OBJECTIVE

To study the relationship pattern of intracranial hemorrhage in cases of traumatic petrous temporal bone fracture.

METHODS

All head injury cases admitted to the Emergency Department, Hospital Tengku Ampuan Afzan, Pahang, Malaysia in 2008 were assessed. Computerized tomography (CT) scan of the skull base was performed in indicated cases. Patients with a petrous temporal bone fracture were included in the study. Subsequent magnetic resonance imaging (MRI) was performed. Intracranial hemorrhages incidence, management and outcome were recorded.

RESULTS

From 1421 cases of head injury, 49(3.4%) patients were diagnosed to have a petrous bone fracture from the CT scan. Only 46 cases underwent MRI scan and were included in this study. Of these, 36(78.3%) cases had associated intracranial hemorrhages (p<0.01). Intracranial hemorrhage was associated with the longitudinal types of petrous fracture (p<0.05). Subdural hematoma was the most prevalent type of bleed (55.6%). There was no association between the types of intracranial bleeding (extradural, subdural, subarachnoid or intracerebral hemorrhage) and the types of petrous bone fracture (longitudinal, oblique or transverse). The mortality rate was 17.4%. The mortality cases were associated with the presence of other skull bone fractures (p<0.05).

CONCLUSIONS

Petrous fracture is significantly associated with intracranial hemorrhage. There was no association between the types of petrous fracture and the types of intracranial hemorrhages in our material.

Contrecoup injury in patients with traumatic temporal bone fracture

OBJECTIVE

To study the prevalence and patterns of contrecoup injury in traumatic temporal bone fracture cases.

METHOD

A prospective, cohort study was undertaken of all patients with traumatic head injury admitted to a tertiary referral hospital in Malaysia within an 18-month period. High resolution computed tomography scans of the brain and skull base were performed in indicated cases, based on clinical findings and Glasgow coma score. Patients with a one-sided temporal bone fracture were selected and subsequent magnetic resonance imaging performed in all cases. Contrecoup injury incidence, type, severity and outcome were recorded.

RESULTS

Of 1579 head injury cases, 81 (5.1 per cent) met the inclusion criteria and were enrolled in the study. Temporal bone fractures were significantly associated with intracranial injuries (p < 0.001). The incidence of a contrecoup injury in cases with temporal bone fracture was 13.6 per cent. Contrecoup injury was significantly associated with petrous temporal bone fracture (p < 0.01). The commonest contrecoup injury was cerebral contusion, followed by extradural haematoma and subdural haematoma.

CONCLUSION

Contrecoup injury is not uncommon in cases of temporal bone fracture, and is significantly associated with petrous temporal bone fracture.