Congenital Abnormalities ; diagnosis ; Diagnostic Imaging ; Ear, Inner ; abnormalities ; Humans

Ear, Inner/diagnostic imaging* ; Temporal Bone/diagnostic imaging* ; Tomography, X-Ray Computed/methods*

OBJECTIVETo provide a valuable imaging anatomic method for operation of the posterior transpetrosal approach and accurate positioning among relative structures in order to reduce the incidence of surgical complications.

METHODSThe clinical information of 119 adult cases (238 sides) was analyzed. All the cases underwent 16 layer helix CT scanning and three-dimensional image reconstruction of skull base without a skull base disease. Axial and coronal images were reconstructed using multiplanar reconstruction technique of ADW 4.2 workstation, and the anatomic objective structure were displayed by rotating imaging slices. The data were analyzed in statistically and compared with the published cadaver data.

RESULTSQuantitative measurement of anatomic structure was shown as below: The distance of width of sigmoid sinus was (11.14 + or - 2.13) mm, the distance of depth of sigmoid sinus was (6.04 + or - 1.67) mm; the distance from the lateral wall of sigmoid sinus to the surface of mastoid process was (9.74 + or - 2.95) mm; the distance from the anterior wall of sigmoid sinus to the posterior wall of external auditory meatus was (12.98 + or - 2.71) mm; the distance from the most posterior portion of the posterior semicircular canal to the anterior wall of sigmoid sinus was (9.87 + or - 2.60) mm; the distance from the most posterior portion of the posterior semicircular canal to the posterior pyramidal wall was (3.18 + or - 1.30) mm; the distance from the posterior extremity of long axis of the lateral semicircular canal to the anterior wall of sigmoid sinus was (13.17 + or - 2.59) mm; the distance from the posterior extremity of long axis of the lateral semicircular canal to the posterior pyramidal wall was (5.46 + or - 1.38) mm; the vertical distance from the lateral semicircular canal to the jugular bulb was (6.69 + or - 3.08) mm; and the distance from the vertical portion of facial nerve to the jugular bulb was (5.32 + or - 2.13) mm. Statistically, there were no significant differences between imaging quantitative measurement and published cadaver data. However, the measurement result, included the distance from the lateral wall of sigmoid sinus to the surface of mastoid process and the distance from the lateral semicircular canal to the jugular bulb as well as the distance from the vertical portion of facial nerve to the jugular bulb, were found a positively correlated to the distance from the anterior wall of sigmoid sinus to the posterior wall of external auditory meatus (r value was 0.284, 0.145, 0.208, respectively, all P < 0.05).

CONCLUSIONSThe result of three-dimensional quantitative measurement by using multiplanar reconstruction technique of 16 layer spiral CT could represent a real distance of anatomic structures. The reconstruction of spiral CT images could display a anatomic feature of temporal bone accurately, and it may provide a valuable method for surgical approach and accurate positioning of relative structure in operation. As the location of sigmoid sinus moving forward, the lateral shift of it may occur more easily and the jugular bulb become closer to the vertical portion of facial nerve, while the extension of anterior location in sigmoid sinus should be a positively correlated to the height of jugular bulb.

Adult ; Aged ; Cranial Sinuses ; diagnostic imaging ; Ear, Inner ; diagnostic imaging ; Ear, Middle ; diagnostic imaging ; Female ; Humans ; Imaging, Three-Dimensional ; Male ; Middle Aged ; Semicircular Canals ; diagnostic imaging ; Temporal Bone ; diagnostic imaging ; Tomography, Spiral Computed

OBJECTIVETo explore multiple slices computed tomography (MSCT) and magnetic resonance imaging (MRI) features of duplication of the internal auditory canal (DIAC) in order to improve the accuracy of diagnosis.

METHODSFour cases (5 ears) were analyzed and the related documents were reviewed retrospectively. MSCT was performed on all cases, and two cases had MRI scanning at the same time.

RESULTSMSCT has shown that the internal auditory canal were divided into two canals by a bony septum in 5 ears. The superior canal ended in a very narrow connection to the facial canal, the inferior portion ended in connection to the cochlea and vestibule. The bony septums from the 2 ears were found no longer intact. The sum of diameter of the two canals was greater than 2 mm. In addition, 5 ears were found to have an enlarged vestibules and the hypoplasia lateral semicircular canals, and meanwhile, 2 ears of them were combined with ipsilateral microtia. Also 1 case of them was combined with microtia, outer acoustic atresia as well as abnormal middle ear. Multiplanar reconstruction and volume rendering images can entirely show the bony septum and two canals. In this study, the vestibular nerve, cochlear nerve and facial nerve were total hypoplastic in one ear, in the other ear, the vestibular and cochlear nerve were hypoplastic, and however, the facial nerve was intact.

CONCLUSIONSMSCT can clearly depict duplication of the internal auditory canals and concomitant anomalies. MRI can clearly show the neural components and their associated malformation.

Child ; Child, Preschool ; Ear, Inner ; diagnostic imaging ; pathology ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Retrospective Studies ; Tomography, Spiral Computed

OBJECTIVE: To observe the inner ear structure with volume rendering (VR) reconstruction and to evaluate the role of high-resolution computed tomography (HRCT) in congenital inner ear malformations. METHOD: HRCT scanning was performed in 10 patients (20 ears) without ear disease (control group) and 7 patients (11 ears) with inner ear malformations (IEM group) and the original data was processed with VR reconstruction. The inner ear osseous labyrinth structure in the images generated by these techniques was observed respectively in the normal ears and malformation ears. RESULT: The inner ear osseous labyrinth structure and the relationship was displayed clearly in VR imaging in the control group,meanwhile, characters and degree of malformed structure were also displayed clearly in the IEA group. Of seven patients (11 ears) with congenital inner ear malformations, the axial, MPR and VR images can display the site and degree in 9 ears. VR images were superior to the axial images in displaying the malformations in 2 ears with the small lateral semicircular canal malformations. The malformations included Mondini deformity (7 ears), vestibular and semicircular canal malformations (3 ears), vestibular aqueduct dilate (7 ears, of which 6 ears accompanied by other malformations) , the internal auditory canal malformation (2 ears, all accompanied by other malformations). CONCLUSION HRCT can display the normal structure of bone inner ear through high quality VR reconstructions. VR images can also display the site and degree of the malformations three-dimensionally and intuitively. HRCT is valuable in diagnosing the inner ear malformation.
Child ; Child, Preschool ; Ear, Inner ; abnormalities ; diagnostic imaging ; Female ; Humans ; Imaging, Three-Dimensional ; Male ; Tomography, X-Ray Computed ; methods

OBJECTIVEThe aim of this study was to find an accurate and feasible measurement technique for the inner ear structures using computed tomography and to check the inter-observer agreement

METHODSSixty patients without abnormal structure of temporal bones confirmed by means of high-resolution computed tomography were included in this study. The multi-planar reformations (MPR) were performed to show the maximum profile of cochlear, and to measure the height and width of cochlear. Areas of bony island encircled by three semicircular canals were measured on the MPR images that could show the whole canal. The data measured by two readers independently was compared to check the inter-observer agreement.

RESULTSThe application of MPR yielded satisfactory anatomic presentation of inner ear for radiologic measurements. There was good inter-observer agreement revealed by the paired t-test and correlation analysis (P>0.05, r>0.9). The height of cochlear (x+/-s) was (4.26+/-0.28) mm while the width of cochlear was (7.03+/-0.39) mm. The areas of bony islands encircled by the anterior, posterior and lateral semicircular canals were (25.49+/-3.84) mm2, (20.07+/-2.93) mm2 and (11.50+/-1.94) mm2, respectively.

CONCLUSIONSMPR can display structures of cochlear and semicircular canals on planes along their central axis. Normative measurements on these MPR images derive excellent repeatability and provide reliable morphologic parameters of inner ear structures.

Adolescent ; Adult ; Aged ; Child ; Cochlea ; diagnostic imaging ; Ear, Inner ; diagnostic imaging ; Female ; Humans ; Male ; Middle Aged ; Semicircular Canals ; diagnostic imaging ; Tomography, X-Ray Computed ; methods ; Young Adult

OBJECTIVE: To observe normal and abnormal findings of foramina within internal auditory canal (IAC) fundus with Virtual Endoscopy of multisection helical Computed Tomography. METHOD: CT scanning of temporal bone was undergone in 25 volunteers (50 ears) in the normal group, in 8 cases (13 ears) with foramina hypoplasia within IAC fundus which were shown on CT and MRI images. CT virtual endoscopy (CTVE) findings were observed in the normal and abnormal groups. The lower threshold value was 900-1200 HU, the upper value was 3,071 HU in CTVE definitions. RESULT: The shape and position of foramina within IAC fundus were shown on the CTVE image, 50 foramina within IAC fundus were shown in all normal cases. In abnormal group, 9 ears were shown as IAC fundus disorder and foramina absent, only 1 foramina was shown in 1 ear, 2 foramen in 4 ears, 3 foramen in 2 ears, 4 foramen in 2 ears; Abnormal shape of cochlear nerve foramina was seen in 4 ears. Other malformations were also shown, including IAC malformations in 3 ears and inner ear malformations in 8 ears. CONCLUSION CTVE is useful to show the shape and position of normal foramina and pathological changes in the patients with foramina hypoplasia within IAC fundus.
Adolescent ; Adult ; Case-Control Studies ; Child ; Child, Preschool ; Cochlear Nerve ; abnormalities ; diagnostic imaging ; Ear Canal ; abnormalities ; diagnostic imaging ; Ear, Inner ; abnormalities ; diagnostic imaging ; Female ; Hearing Loss, Sensorineural ; congenital ; diagnostic imaging ; Humans ; Male ; Middle Aged ; Tomography, Spiral Computed ; methods ; Young Adult

OBJECTIVETo investigate multiple slice computed tomography (MSCT) and magnetic resonance imaging (MRI) features of congenital stenosis of the internal auditory canal (CSIAC) and improve the ability for diagnosis.

METHODThirteen cases with fifteen ears were studied. In all cases a MSCT and MRI was performed.

RESULTSEleven cases were unilateral, and 2 cases were bilateral. MSCT could show the narrowness of IAC. Three cases were isolated, but the others were combined with inner ear malformations. One ear had inner, middle and outer ear malformations. One ear had inner, middle, and outer ear malformations with a frontal bone malformation. MRI demonstrated that all of the vestibulocochlear nerves were hypoplastic. The cochlear nerve in seven ears was not present, in seven ears the nerve was thinner, and in the last case it was poorly visualized. The facial nerve in two ears was hypoplastic. Volume rendering (VR) could present the degree of the narrowed internal auditory canals, combined with other inner ear anomalies.

CONCLUSIONMSCT will show the degree of the narrow internal auditory canals and combined anomalies, while the MRI can further demonstrate the nerves' development.

Adolescent ; Adult ; Child ; Child, Preschool ; Constriction, Pathologic ; diagnostic imaging ; pathology ; Ear, Inner ; abnormalities ; diagnostic imaging ; pathology ; Female ; Humans ; Infant ; Magnetic Resonance Imaging ; Male ; Tomography, Spiral Computed ; Young Adult

Inner ear malformations are anomalies linking to development insults at different periods of embryogenesis,which are common causes of congenital sensorineural hearing loss. The evaluation of pediatric sensorineural hearing loss mostly depends on high-resolution computed tomography and magnetic resonance imaging, which can excellently depict the temporal bones and inner ear malformations.
Ear, Inner ; abnormalities ; diagnostic imaging ; embryology ; Hearing Loss, Sensorineural ; congenital ; Humans ; Magnetic Resonance Imaging ; Temporal Bone ; abnormalities ; diagnostic imaging ; Tomography, X-Ray Computed

OBJECTIVETo evaluate the feasibility and usability of multi-slice computed tomography (MSCT) in congenital inner ear malformations.

METHODSFourty-four patients with sensorineural hearing loss (SNHL) were examined by a Somatom Sensation 16 (siemens, Germany) CT scanner with following parameters: 120 kV, 100 mAs, 0.75 mm collimation, 1 mm reconstruction increment, a pitch factor of 1 and a field of view of 100 mm. The axial images of interested ears were reconstructed with 0.1 mm reconstruction increment, and a field of view of 50 mm. The 3D reconstructions were done with volume rendering technique (VRT) on the workstation (3D Virtuoso and Wizard,siemens).

RESULTSTwenty-five patients were normal and 19 patients (36 ears) were congenital inner ear malformations among 44 patients scanned with MSCT. Of the malformations, all the axial, MPR and VRT images can display the site and degree in 33 ears. VRT images were superior to the axial images in displaying the malformations in 3 ears with the small lateral semicircular canal malformations. The malformations were Michel deformity (1 ear), common cavity deformity (3 ears), incomplete partition I (3 ears), incomplete partition II (Mondini deformity, 5 ears), vestibular and semicircular canal malformations( 14 ears), vestibular aqueduct dilate( 16 ears, of which 6 ears accompanied by other malformations), the internal auditory canal malformation(8 ears, all accompanied by other malformations).

CONCLUSIONMSCT allows a comprehensively assessing various congenital ear malformations through high quality MPR and VRT reconstructions. VRT images can display the site and degree of the malformations three-dimensionally and intuitionisticly. It is very useful to the cochlear implantation.

Adolescent ; Adult ; Case-Control Studies ; Child ; Child, Preschool ; Congenital Abnormalities ; diagnostic imaging ; Ear, Inner ; abnormalities ; diagnostic imaging ; Female ; Humans ; Male ; Tomography, Spiral Computed ; Young Adult