Three-dimensional Fourier transformation constructive interference in steady state magnetic resonance imaging of the inner ear in patients with unilateral and bilateral Menière's disease

OBJECTIVE

In this study, three-dimensional Fourier transformation constructive interference in steady state (3DFT-CISS) magnetic resonance imaging was used to quantify the distance between the vertical part of the posterior semicircular canal and the posterior fossa as a measure of the endolymphatic sac and duct in patients with Menière's disease. Differences in this distance between affected and unaffected ears, as well as differences between unilaterally and bilaterally affected patients, were studied and compared with a control group. Also, possible correlations between the measured distance and the duration and severity of symptoms, patient age, and average hearing loss were investigated in the group of patients with Menière's disease.

STUDY DESIGN

Retrospective clinical study.

SETTING

Tertiary referral center (University Hospital) as part of a large, diagnostic research project on Menière's disease.

PATIENTS

Of the 111 patients with Menière's disease initially included, 90 patients underwent 3DFT-CISS MRI. Eighty-six of these patients were analyzed in this MRI study. Fifty-six patients had unilateral Menière's disease, and 30 patients had bilateral Menière's disease (116 affected and 56 unaffected ears). Sixty-two ears in patients without Menière's disease were studied as controls.

INTERVENTION

The distance between the vertical part of the posterior semicircular canal and the posterior fossa was determined by 3DFT-CISS MRI.

MAIN OUTCOME MEASURES

Contiguous axial 3DFT-CISS MRI slices of 0.7 to 1.0 mm were made by a radiologist according to a strict protocol. Measurements of the distance between the vertical part of the posterior semicircular canal and the posterior fossa were taken by two professionals-a radiologist and an otolaryngologist-using a ruler and the original scan.

RESULTS

A significantly smaller distance (2.9 mm) between the vertical part of the posterior semicircular canal and the posterior fossa as visualized on MRI scans was found in the ears of patients with Menière's disease than in the ears of patients in the control group (3.8 mm, p < 0.001). In both uni- and bilaterally affected patients (n = 56 and n = 30, respectively), no significant difference between ears was found (p = 0.44 and p = 0.19, respectively). In bilaterally affected patients, however, this distance (3.2 mm) was significantly greater than the distance in unilaterally affected patients (2.7 mm, p = 0.004). There was no relationship between the MRI-visualized distance between the vertical part of the posterior semicircular canal and the posterior fossa and the duration of disease, average hearing loss, or severity of symptoms in uni- and bilaterally affected patients.

CONCLUSION

The difference in MRI-visualized distances between the vertical part of the posterior semicircular canal and the posterior fossa of uni- and bilaterally affected patients strongly suggests that unilateral and bilateral hearing loss are two different entities in patients with Menière's disease. The size of the endolymphatic sac seems not to be the only factor in the pathogenesis of Menière's disease. That the MRI-visualized distance between the vertical part of the posterior semicircular canal and the posterior fossa does not have any relationship to the duration of the disease or to patient age indicates that this distance is a congenital feature.

Magnetic resonance imaging of the inner ear in patients with idiopathic sudden sensorineural hearing loss

Although gadolinium-enhanced magnetic resonance imaging (Gd-MRI) has been used to indicate the presence of a subclinical labyrinthitis in patients with idiopathic sudden sensorineural hearing loss (ISSHL), its sensitivity in daily clinical practice is unknown. We describe Gd-MRI findings in 27 ISSHL patients taking part in a prospective multicenter clinical trial. MRI findings were related to the severity of the hearing loss, vestibular involvement and the time interval between the occurrence of ISSHL and imaging. Pathological enhancement of the cochlea indicating a labyrinthitis was found in one patient with ISSHL. In 26 cases, no pathological enhancement could be established. Study results indicate that the present sensitivity of Gd-MRI is low for detecting subclinical viral labyrinthitis in patients with ISSHL. To improve the sensitivity of MRI in ISSHL, we recommend that imaging is performed as early as possible, preferably before treatment is started.

Simultaneous occurrence of a supra- and an infratentorial glioma in a patient with Ollier's disease: more evidence for non-mesodermal tumor predisposition in multiple enchondromatosis

A case is presented in which two neuro-ectodermal tumors, an infra- and a supratentorial glioma, developed in a young man with multiple enchondromatosis of Ollier's disease. This is the third such case of multifocal low-grade glioma in Ollier's disease, suggesting a predisposition for non-mesodermal tumors in Ollier's disease. The related condition of multiple enchondromatosis and hemangiomas (Maffucci's syndrome) is well known for its malignant potential, developing both mesodermal and non-mesodermal tumors. Along with other authors, we support the concept of two variants of the same disease with a predisposition to development of tumors from various germ layers.

Painful Horner syndrome due to arteritis of the internal carotid artery

A 44-year-old man presented with painful Horner syndrome: severe periorbital pain, ptosis, and miosis of his right eye, with intact facial sweating. Lymphadenitis at the right side of his neck preceded the symptoms. MRI and magnetic resonance angiography showed thickening of the right internal carotid artery, extending from the bifurcation to the cavernous sinus, without evidence for dissection. The patient was treated with corticosteroids with immediate improvement. Control MRI scanning was normal after 6 weeks. We conclude that the painful Horner syndrome was caused by a reactive arteritis of the right internal carotid artery.

The origin of lactate in peritumoral edema as measured by proton-magnetic resonance spectroscopic imaging

Using in vivo proton-magnetic resonance spectroscopy (1H-MRS), which allows the measurement of metabolites of adequate tissue concentration, the origin of lactate in peritumoral edema has been assessed by comparison with lactate levels in the central and marginal areas of the tumor in 18 patients with cerebral gliomas. In the majority of cases lactate content in the area of peritumoral edema was lower than that in the tumor margin or tumor center, which is consistent with the assumption that the tumor is the source of lactate, which then reaches the surrounding area of edema by diffusion. In 3 of the 18 cases the amount of lactate in the peritumoral edematous tissue was higher than in the tumor, indicating that the lactate is locally produced on account of ischemia due to regional elevation of tissue pressure in the edematous area.

Adult neuroblastoma: a report of two cases

Neuroblastoma is an uncommon tumour arising from neural crest tissue. It is predominantly a tumour of childhood with a peak incidence in the first 3 years of life. In the USA the incidence is only about 500 paediatric cases per year. In adults it is an even more rare tumour. In 1986 Allan et al. spoke of a total of 39 reported cases of adult neuroblastoma in the world literature, with exception of some additional reports of cerebral neuroblastoma and peripheral neuro-epithelioma. Therefore neuroblastoma may cause both diagnostic and therapeutic problems. We report two recent cases of adult neuroblastoma.