Preoperative imaging assessment of chronic otitis media: what does the otologist need to know?

Correlation of pre-operative computed tomography, intra-operative findings and surgical outcomes in revision tympanomastoidectomy

OBJECTIVE

To correlate pre-operative computed tomography findings, intra-operative details and surgical outcomes with cholesteatoma recurrence in revision tympanomastoidectomy.

METHODS

This retrospective, non-randomised, single-institution cohort study included 42 patients who underwent pre-operative computed tomography imaging and revision surgery for recurrent chronic otitis media. Twelve disease localisations noted during revision surgery were correlated with pre-operative temporal bone computed tomography scans. A matched pair analysis was performed on patients with similar intra-operative findings, but without pre-operative computed tomography scans.

RESULTS

Pre-operative computed tomography identified 25 out of 31 cholesteatoma recurrences. Computed tomography findings correlated with: recurrent cholesteatoma when attic opacification and ossicular chain involvement were present; and revision surgery type. Sinodural angle disease, posterior canal wall erosion and dehiscent dura were identified as predictors of canal wall down tympanomastoidectomy. Patients with pre-operative computed tomography scans had a higher rate of cholesteatoma recurrence, younger age at diagnosis of recurrent disease, more revision surgical procedures and less time between previous and revision surgical procedures (all p < 0.05).

CONCLUSION

Pre-operative imaging and intra-operative findings have important clinical implications in revision surgery for chronic otitis media. Performing pre-operative computed tomography increases diagnosis accuracy and reduces the time required to diagnose recurrent disease.

Tympanomastoid cholesterol granuloma: radiological and intraoperative findings of blood source connection

The hypothesis that the close contiguity between the cholesterol granulomas and some rich blood sources provided the trigger to the aggressive nature of tympanomastoid cholesterol granulomas has been recently reported. To corroborate this new etiopathogenetic theory we retrospectively reviewed a series of 14 patients with primary middle ear and mastoid cholesterol granulomas and investigated the temporal bone marrow invasion and its hematopoietic potentialities and a possible cholesterol granulomas contiguity with relevant vascular structures such as the carotid artery, sigmoid jugular system, mastoid or dural vein. Eight cases did not show radiological sign of bone marrow invasion or hematopoietic potentialities visible in MRI. Besides no intraoperative vascular connections that could explain an initial bleeding source were found. Cholesterol granulomas bone marrow invasion was present in six patients. A bone marrow hematopoietic potentiality was showed in four of these patients, whereas, an evident anatomical contiguity of the cholesterol granuloma with some important temporal bone vascular structures was visible in five cases. Analysis of cardiovascular risk factors showed that four patients presented one or more of the risk factors analysed.

Computed Tomography Staging of Middle Ear Cholesteatoma

Background

To establish computed tomography (CT) staging of middle ear cholesteatoma and assess its impact on the selection of the surgical procedure.

Material/Methods

Prospective study was conducted on 61 consecutive patients (mean age 26.8 years) with middle ear cholesteatoma. CT scan of the temporal bone and surgery were performed in all patients. CT staging classified cholesteatoma according to its location in the tympanic cavity (T); extension into the mastoid (M); and associated complications (C). Cholesteatoma was staged as stage I (T1, T2), stage II (T3, M1, M2, C1), and stage III (C2).

Results

The overall sensitivity of CT staging of cholesteatoma compared to surgery was 88% with excellent agreement and correlation between CT findings and intra-operative findings (K=0.863, r=0.86, P=0.001). There was excellent agreement and correlation of CT staging with surgical findings for T location (K=0.811, r=0.89, P=0.001), good for M extension (K=0.734, r=0.88, P=0.001), and excellent for associated C complications (K=1.00, r=1.0, P=0.001). Atticotympanotomy was carried out in stage I (n=14), intact canal wall surgery was performed in stage II (n=38), and canal wall down surgery was done in stage III (n=5) and stage II (n=4).

Conclusions

We established CT staging of middle ear cholesteatoma that helps surgeons to select an appropriate surgery.

Location of the middle cranial fossa dural plate in patients with chronic otitis media

AIM

This study aimed to determine whether or not the middle cranial fossa dural plate is located lower (i.e. more caudally) in patients with chronic otitis media, relative to adjacent structures.

METHODS

The authors retrospectively investigated computed tomography temporal bone scans of 267 ears of 206 patients who had undergone surgery with a diagnosis of chronic otitis media, together with scans of 222 ears of 111 patients without chronic otitis media. The depth of the middle cranial fossa dural plates was recorded.

RESULTS

The mean depth of the middle cranial fossa dural plate was 4.59 mm in the study group and 2.71 mm in the control group (p < 0.001). The middle cranial fossa dural plate was located lower in the right ear in both the study and control groups.

CONCLUSION

The middle cranial fossa dural plate was located lower in patients with chronic otitis media, and in the right ears of both patients and controls. Surgeons should take this low location into consideration, and take extra care, during relevant surgery on patients with chronic otitis media.