Limits...
The Usefulness of Reconstructed 3D Images in Surgical Planning for Cochlear Implantation in a Malformed Ear with an Abnormal Course of the Facial Nerve.

Hara M, Takahashi H, Kanda Y - Clin Exp Otorhinolaryngol (2012)

Bottom Line: CI was performed with no problems, in the same manner as in Case 1.We were able to successfully depict the structures of the inner ear, ossicles, and FN as 3D images, which are very easy to understand visually and intuitively.These 3D images of the malformed ear are useful in preoperative image simulation and in surgical planning for those performing a CI procedure.

View Article: PubMed Central - PubMed

Affiliation: Department of Otorhinolaryngology Head and Neck Surgery, Nagasaki University Hospital, Nagasaki, Japan.

ABSTRACT

Objectives: It is not unusual for a cochlear implantation (CI) candidate to have some type of ear malformation, in particular an abnormal course of the facial nerve (FN). In this study, we attempted to reconstruct a three-dimensional (3D) image of temporal bone structures with malformation using computed tomography (CT) imaging and examined its usefulness in the surgical planning of CI in a malformed ear.

Methods: We prepared 3D images for 6 separate CI cases before surgery. First, we manually colored preoperative CT images using Photoshop CS Extended. We then converted the colored CT images to 3D images using Delta Viewer, free-ware for Macintosh. Before surgery, we discussed any problems anticipated based on the 3D images and plans for surgery with those who would be performing the CI.

Results: Case 1: The subject was a 3-year-old boy with malformed ossicles, semicircular canal (SC) hypoplasia, internal auditory canal stenosis, and an abnormal course of the FN. 3D image indicated that the stapes were absent, and the FN was more anteriorly displaced, so that it was difficult to perform cochleostomy. The surgical findings were similar to those depicted on the 3D image, so we could insert an electrode based on the preoperative image simulation without complications. Case 2: The subject was a 7-year-old boy with malformed stapes, atresia of the round window, cochlear and SC aplasia, and an abnormal course of the FN with bifurcation. CI was performed with no problems, in the same manner as in Case 1.

Conclusion: We were able to successfully depict the structures of the inner ear, ossicles, and FN as 3D images, which are very easy to understand visually and intuitively. These 3D images of the malformed ear are useful in preoperative image simulation and in surgical planning for those performing a CI procedure.

No MeSH data available.


Related in: MedlinePlus

The images of the surgical field of posterior tympanotomy as shown by the orange oval. (A) Case 1: close-up image of the rectangle of Fig. 4A. The stapes (S) and crus of the incus (I) are absent, and the facial nerve (FN) is antero-inferiorly displaced. Dashed line shows the position of the ossicles and facial nerve (FN) of normal control. The visible area of the basal turn of cochlea (Co) is smaller than normal. (B) Normal control: close-up image of the rectangle of Fig.4B. (C) The picture of the surgical findings of case 1. The visible area of the promontory (Pro) for cochleostomy is narrow and surrounded by the chorda tympani nerve (CTyN) and facial nerve (FN) displaced anteriorly.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3369982&req=5

Figure 5: The images of the surgical field of posterior tympanotomy as shown by the orange oval. (A) Case 1: close-up image of the rectangle of Fig. 4A. The stapes (S) and crus of the incus (I) are absent, and the facial nerve (FN) is antero-inferiorly displaced. Dashed line shows the position of the ossicles and facial nerve (FN) of normal control. The visible area of the basal turn of cochlea (Co) is smaller than normal. (B) Normal control: close-up image of the rectangle of Fig.4B. (C) The picture of the surgical findings of case 1. The visible area of the promontory (Pro) for cochleostomy is narrow and surrounded by the chorda tympani nerve (CTyN) and facial nerve (FN) displaced anteriorly.

Mentions: Fig. 5 shows the preoperative DV-3D image and the actual picture of the surgical findings. The space for cochlear fenestration was very narrow; however, we were able to insert an electrode based on the preoperative DV-3D image without any complications, such as FN palsy or stimulation. Fig. 6 shows an X-ray of the electrode: MED-EL, standard.


The Usefulness of Reconstructed 3D Images in Surgical Planning for Cochlear Implantation in a Malformed Ear with an Abnormal Course of the Facial Nerve.

Hara M, Takahashi H, Kanda Y - Clin Exp Otorhinolaryngol (2012)

The images of the surgical field of posterior tympanotomy as shown by the orange oval. (A) Case 1: close-up image of the rectangle of Fig. 4A. The stapes (S) and crus of the incus (I) are absent, and the facial nerve (FN) is antero-inferiorly displaced. Dashed line shows the position of the ossicles and facial nerve (FN) of normal control. The visible area of the basal turn of cochlea (Co) is smaller than normal. (B) Normal control: close-up image of the rectangle of Fig.4B. (C) The picture of the surgical findings of case 1. The visible area of the promontory (Pro) for cochleostomy is narrow and surrounded by the chorda tympani nerve (CTyN) and facial nerve (FN) displaced anteriorly.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3369982&req=5

Figure 5: The images of the surgical field of posterior tympanotomy as shown by the orange oval. (A) Case 1: close-up image of the rectangle of Fig. 4A. The stapes (S) and crus of the incus (I) are absent, and the facial nerve (FN) is antero-inferiorly displaced. Dashed line shows the position of the ossicles and facial nerve (FN) of normal control. The visible area of the basal turn of cochlea (Co) is smaller than normal. (B) Normal control: close-up image of the rectangle of Fig.4B. (C) The picture of the surgical findings of case 1. The visible area of the promontory (Pro) for cochleostomy is narrow and surrounded by the chorda tympani nerve (CTyN) and facial nerve (FN) displaced anteriorly.
Mentions: Fig. 5 shows the preoperative DV-3D image and the actual picture of the surgical findings. The space for cochlear fenestration was very narrow; however, we were able to insert an electrode based on the preoperative DV-3D image without any complications, such as FN palsy or stimulation. Fig. 6 shows an X-ray of the electrode: MED-EL, standard.

Bottom Line: CI was performed with no problems, in the same manner as in Case 1.We were able to successfully depict the structures of the inner ear, ossicles, and FN as 3D images, which are very easy to understand visually and intuitively.These 3D images of the malformed ear are useful in preoperative image simulation and in surgical planning for those performing a CI procedure.

View Article: PubMed Central - PubMed

Affiliation: Department of Otorhinolaryngology Head and Neck Surgery, Nagasaki University Hospital, Nagasaki, Japan.

ABSTRACT

Objectives: It is not unusual for a cochlear implantation (CI) candidate to have some type of ear malformation, in particular an abnormal course of the facial nerve (FN). In this study, we attempted to reconstruct a three-dimensional (3D) image of temporal bone structures with malformation using computed tomography (CT) imaging and examined its usefulness in the surgical planning of CI in a malformed ear.

Methods: We prepared 3D images for 6 separate CI cases before surgery. First, we manually colored preoperative CT images using Photoshop CS Extended. We then converted the colored CT images to 3D images using Delta Viewer, free-ware for Macintosh. Before surgery, we discussed any problems anticipated based on the 3D images and plans for surgery with those who would be performing the CI.

Results: Case 1: The subject was a 3-year-old boy with malformed ossicles, semicircular canal (SC) hypoplasia, internal auditory canal stenosis, and an abnormal course of the FN. 3D image indicated that the stapes were absent, and the FN was more anteriorly displaced, so that it was difficult to perform cochleostomy. The surgical findings were similar to those depicted on the 3D image, so we could insert an electrode based on the preoperative image simulation without complications. Case 2: The subject was a 7-year-old boy with malformed stapes, atresia of the round window, cochlear and SC aplasia, and an abnormal course of the FN with bifurcation. CI was performed with no problems, in the same manner as in Case 1.

Conclusion: We were able to successfully depict the structures of the inner ear, ossicles, and FN as 3D images, which are very easy to understand visually and intuitively. These 3D images of the malformed ear are useful in preoperative image simulation and in surgical planning for those performing a CI procedure.

No MeSH data available.


Related in: MedlinePlus