F. Veillon

Imaging of the windows of the temporal bone.

Imaging of the window of the temporal bone has became an important tool in the analysis of hearing loss, vertigo, tinnitus in a context of trauma, malformation, otosclerosis, and chronic otitis media. A good knowledge of the anatomy and a good technical procedure are necessary for making an efficient diagnosis. The increased thickness of the footplate may be delineated in otosclerosis, chronic otitis media, malformation, when it is measured at 0.7 mm or more in horizontal computed tomography (CT) sections. The traumatic displacement of the stapes, particularly within the labyrinths, is easily diagnosed in horizontal CT section. Imaging of the round window is now very important for the detection of otosclerotic foci, congenital stenosis, and perilymphatic fistula with or without fracture. Magnetic resonance imaging (MRI) with the high-resolution T2 plays an important role in the detection of a small amount of fluid in the round window recess, confirming the traumatic perilymphatic fistula without fracture.

Imagerie de l’otospongiose : confrontation clinique et imagerie

Resume L’otospongiose represente une frequente osteodystrophie primitive de l’os labyrinthique dont le diagnostic necessite d’etre confirme par un examen tomodensitometrique afin d’eliminer les autres causes qui peuvent aboutir a un syndrome clinique de surdite de transmission avec abolition des reflexes stapediens: fixation de la tete du marteau a la paroi laterale de la cavite tympanique, absence de longue apophyse de l’enclume ou de l’etrier, oreille Geyser, cholesteatome primitif, neurinome du nerf facial tympanique bloquant l’etrier. Certaines formes particulieres d’otospongiose doivent etre precisees: atteinte de la fenetre ronde (resultats post-chirurgicaux moins bons), extension a la cavite tympanique bloquant le marteau et/ou l’enclume, a la lumiere labyrinthique, au conduit auditif interne (forme tres rare). La position du canal facial tympanique, l’existence d’anomalies associees: artere stapedienne, malformation des osselets et/ou du labyrinthe, otite chronique doivent egalement etre precisees. L’IRM est reservee aux extensions intralabyrinthiques, intrameatiques internes et aux complications post-operatoires avec labyrinthite. L’ensemble permet ainsi d’eviter toutes les surprises operatoires prejudiciables au patient. Elle permet egalement d’evaluer le caractere actif ou non des foyers (captation ou non du gadolinium).

Pathology of the Facial Nerve

A good examination in facial nerve imaging (CT or MR imaging) depends on a good knowledge of anatomy. Two clinical situations must be considered: imaging of patients with or without facial palsy. CT and MR imaging are very useful when the symptoms are atypical or progressive: MR imaging gives very good information about the facial nerve inflammation but may also discover a schwannoma, a hemangioma, a meningioma, or a primitive or secondary cholesteatoma. In malignant tumors of the parotid gland, a study of the fallopian canal must always be performed to delineate an extension in the mastoid, tympanic, or intrameatic parts. In some rare cases, a metastasis in the temporal bone may occur, especially in the region of the geniculate ganglion. Particular attention must be paid to children with facial palsy, considering the possibility of a histiocytosis or metastasis of a neuroblastoma.

Venous thromboembolism and occult malignancy: simultaneous detection during pulmonary CT angiography with CT venography.

OBJECTIVE We explored the potential for patients with proven venous thromboembolism or pulmonary embolism (PE) to have occult malignancies detected during the same CT examination. To verify this, we compared the presence of occult malignancies identified on pulmonary artery CT angiography (CTA) and CT venography (CTV) when venous thromboembolism (VTE) was present. SUBJECTS AND METHODS Pulmonary artery CTA combined with CTV was performed on a 16-MDCT scanner on 186 adult patients suspected of having pulmonary embolism without any known malignancies. CTV was performed from the diaphragm to the knee 180 seconds after CTA. Two radiologists evaluated the presence of VTE, that is PE or deep venous thrombosis (DVT), and tumor lesions on both examinations in consensus. The malignant nature of the possibly identified tumors was confirmed by pathologic examination. RESULTS VTE was found in 49 patients (26%). Malignant tumors were detected in 24 patients (13%). Eleven patients with malignant tumors had VTE (46% of patients with malignant tumors; 22% with VTE and 6% of all patients). There was correlation with presence of malignancies between both and DVT and DVT associated with PE but not between presence of malignancies and PE only. Patients with DVT and those with DVT associated with PE had a risk ratio of 3.2 and 3.3, respectively, for having a malignant tumor discovered simultaneously. CONCLUSION A high number of malignant tumors can be incidentally discovered on pulmonary artery CTA, even more so with additional CTV. Radiologists should scrutinize scans to pick up unknown malignancies, especially in patients with identified VTE.

Imaging in sinonasal sarcoidosis: CT, MRI, 67Gallium scintigraphy and 18F-FDG PET/CT features

OBJECTIVES Attempt to describe and analyse the radiological and nuclear medicine patterns of sinonasal sarcoidosis (SNS) still poorly reported in the literature. MATERIAL AND METHODS Retrospective single institution study of 22 consecutive patients with symptomatic biopsy-proven SNS to evaluate the interest of CT, MRI, (67)Ga scintigraphy and (18)F-FDG PET/CT for diagnosis and therapeutic follow-up. RESULTS Nodules of the septum and turbinates are the most suggestive CT and MRI features. Other CT features such as sinusal filling, mucosal thickening, osteosclerosis or destructive sinonasal lesions are not specific and depend on clinical context and evolutive stage of SNS. (18)F-FDG PET/CT provides complete morphofunctional mapping of active inflammatory sites related to sarcoidosis with a better diagnostic sensitivity (100%) compared to (67)Gallium scintigraphy (75%). The changes in (18)F-FDG uptake intensity could reflect the efficacy of treatment. CONCLUSION SNS is an uncommon and probably underdiagnosed phenotype of sarcoidosis. Even if guided biopsy remains necessary for SNS confirmation, medical imaging plays an important role in diagnosis and therapeutic follow-up. CT features with nodules of the septum and/or turbinates are suggestive of SNS contrary to other nonspecific CT findings. CT imaging is directly related severity, reversibility and course of SNS and provide an original radiological staging system in order to predict patient clinical outcome. PET/CT may be used for diagnosis assessement but also to monitor treatment response in a given clinical context, in a patient with histopathologically-proven SNS. Prospective and long term studies are necessary to validate these preliminary results.

Middle ear adenomatous tumor: a not so rare glomus tympanicum-mimicking lesion.

BACKGROUND AND PURPOSE Middle ear adenomatous tumors (MEAT) are rare tumors which can be begin or malignant and can present a neuroendocrine differentiation. Their radiological aspect is very similar to glomus tympanicum (GT) which are the most common tumoral lesions of the middle ear. We present several radiological and clinical findings that could help radiologists to accurately identify MEAT. MATERIAL AND METHODS We retrospectively reviewed the radiological and clinical findings of three patients with MEAT and of eight patients with GT. Diagnostic was obtained after surgical resection in all cases. All patients had high resolution CT and MR of the middle ear associated with a subtracted digital carotid angiography. Tumor location, size, extension, signal intensity, and enhancement were analysed. From the medical records of the patients, clinical manifestations (hearing loss, tinnitus), evolution length and recurrences were noted. RESULTS MEAT and GT appeared as tissular lesion with significant enhancement on CT and MR. A vascular blush was present on angiography in all cases of GT and absent from all cases of MEAT. A close relationship between the tumor and the Jacobsons nerve or its branches was identified in all cases of GT. Pulsatile tinnitus was present in all patients with GT and absent in all patients with MEAT. CONCLUSION A middle ear tissular lesion clearly separated from the Jacobson nerve or its branches, showing significant enhancement after contrast medium injection but with a normal angiography, should make one suspicious for MEAT.

Intérêt de la tomodensitométrie dans la sinusite fongique allergique (SFA)

Purpose. To assess the value of CT for diagnosis and follow-up of AFS. Evaluation of characteristic CT features of AFS. Methods. Retrospective review of 12 cases of AFS presenting with all published diagnostic criteria (1) chronic rhinosinusitis refractory to standard management (2) CT features of chronic sinusitis (3) anatomopathologic, immunoallergologic, biochemical and mycologic criteria. CT findings were correlated with surgical findings and reviewed by one ENT and two radiologists to assess the diagnostic value of different CT features, alone or in association. Results. AFS was isolated in 6 cases, and associated with allergic bronchopulmonary aspergillosis (ABPA) in 6 cases. CT showed pan- or polysinusitis, unilateral or bilateral, with mucosal thickening, sinus opacification frequently heterogeneous, bony changes, fluid trapping, and with pseudotumoral appearance in 3 cases. Conclusion. CT findings alone are not specific or pathognomonic but may suggest AFS in the correct clinical or immunoallergologic setting. It may alert the physician to the need for complementary work-up, exclude the presence of associated lung disease, and better adapt treatment and follow-up.

MRI in respiratory epithelial adenomatoid hamartoma of nasal cavities.

This is a report of six cases of respiratory epithelial adenomatoid hamartoma of the nasal cavities that were characterized by: symptoms of nasal obstruction and dysosmia; endoscopic appearances of bilateral nasal polyposis affecting the olfactory clefts; CT imaging showing enlargement of the olfactory clefts; MRI (rarely reported in the literature) revealing clearly delineated cerebriform tissue filling in the olfactory clefts; histological confirmation in all cases; and recovery after surgical endoscopic resection without the need for associated sinus surgery.

FDG PET coregistered to MRI for diagnosis and monitoring of therapeutic response in aggressive phenotype of sarcoidosis

F-fluorodeoxyglucose(FDG) positron emission tomography (PET) has beenscarcely evaluated in the clinical management of atypicaland aggressive forms of sarcoidosis [3–5].We illustrate the results of morphofunctional imagingobtained in a 28-year-old man with an aggressive pheno-type of sarcoidosis. The diagnosis was histopathologicallyproven by biopsy of nasal and peripheral lymph nodes. T1-weighted MRI with gadolinium contrast enhancement andFDG PET were matched by a fully automated volume-based registration algorithm. Increased FDG uptake wasshown in two nodular lesions of about 17 and 14 mm,respectively, located in the right fornix and left hippocam-pus (a, b). Intense glucose metabolism was also shown insinonasal regions (a, b), oropharynx and parotidscorresponding to MRI abnormalities. Furthermore, whole-body FDG PET/CT revealed additional foci of abnormaluptake suggesting multisystemic sarcoidosis (c). Thesecond PET/CT examination performed 2 months after

Leptomeningeal carcinomatosis and sensorineural hearing loss: correlation of labyrinthine enhancement patterns with symptoms.

OBJECTIVES The purpose of this study was to investigate the correlation between hearing loss and inner ear enhancement in patients suffering from leptomeningeal carcinomatosis (LC) involving the internal acoustic canal (IAC). Previous studies have only reported an association between IAC enhancement and sensorineural deafness. MATERIAL AND METHODS In a prospective study conducted from 2005 to 2007, 14 patients with LC involving the IAC underwent high-resolution MRI and otolaryngology examination. MRI images were analyzed by two experienced radiologists who were blinded to audiologic investigation results. RESULTS Three (21%) patients had IAC and inner ear enhancement on gadolinium-weighted MRI. All three had a sensorineural hearing loss. Eleven (79%) patients had IAC enhancement without inner ear enhancement. Nine of these 11 patients were free of sensorineural hearing loss. Only two of them had sensorineural deafness. CONCLUSION These findings are suggestive of a relation between hearing loss and inner ear enhancement in leptomeningeal carcinomatosis, as previously reported for bacterial meningitis. However, further investigations, including radiopathological correlation and a larger number of patients, are warranted to confirm these preliminary results.