Abstract Otology 2000 C14-1

Bernhard Schick MD (1), Dominik Brors MD (1), Gabriele Kahle MD (2), Wolfgang Draf MD, PhD, FRCS (1)

(1) Department of ENT-Diseases, Head, Neck and Facial Plastic Surgery Academic Teaching Hospital D-Fulda
(2) Institute of Radiology Academic Teaching Hospital D-Fulda

Objectives: Radiological follow-up after surgical treatment in extended jugulotympanic paragangliomas (JTP) is still a challenge. Small residual tumors may escape detection in early radiological follow-up leading to the false assumption of complete tumor resection. The study analysis the effectiveness of complete tumor resection in extended JTP and highlights on the value of computertomography, magnetic resonance imaging and angiography for follow-up. Methods: Retrospective study of 34 extended JTP treated from 01.01.1981 to 31.12.1998 at a tertiary care facility. The study group included 23 paragangliomas at level C and 11 paragangliomas at level D according to the classification proposed by Fisch. The medical reports and radiological follow-up investigations were analysed. Results: 10 of the 34 paragangliomas had already been surgically treated before at the time of first presentation. Twice additional radiation had been performed. In 14 out of 34 JTP the tumor resection in our department was found to be incomplete in radiological follow-up. In two cases only angiography had proved 18 months and three years after surgery a small residual tumor, even magnetic resonance imaging was found to be inconspicuous at the same time. Residual tumor was mainly found at two sides: vertical part of the internal carotid artery and jugular foramen/cerebellopontine angle. Retroclival tumor location and residual tumor lateral to the bony canal of the hypoglossal nerve were single findings. Conclusion: Residual tumor after surgical treatment of extended JTP (level C and D) is not uncommon, but can be highly difficult to visualize. Computertomography and magnetic resonance imaging can fail to detect residual tumor, especially in early follow-up. Small residual tumors may only be recognized in angiography. In order to evaluate the long-term results in paraganglioma treatment a precise follow-up over decades has to be provided.

Abstract Otology 2000 C14-2

Nemesio Gómez Estancona MD, C. Gorostiza MD, A. Mugica MD, J. Elorduy MD, C. Iriarte MD, L. Urruticoechea MD, L. Muñiz MD, A.G. Tena MD

Hospital de Cruces (Vizcaya) E-Bilbao

A 61-year-old man with right ear pain and hearing loss was diagnosed with a glomus jugulare tumor for which he received radiation therapy and after embolization of the tumor total petrosectomy by infratemporal approach without injury to the cranial nerves. One year later labile hypertension and five tumors at the abdominal cavity with surgical excision, excess of catecholamines. One year later develops a pathological hip fracture with tumor metastatic to the sacrum and pelvis.

Abstract Otology 2000 C14-3

Takashi Nakagawa MD, PhD, Yoshihiko Kumamoto MD, Masahiro Iwamoto MD, PhD, Jun-ichi Fukushima MD, Yoshiro Natori MD, PhD, Jun Shinokuma MD, PhD, Shizuo Komune MD, PhD, Sohtaro Komiyama MD, PhD

Department of Otorhinolaryngology Faculty of Medicine Kyushu Univ. J-Fukuoka

Malignant tumor in a peripheral auditory system is not common. Especially, adenocarcinoma in the middle ear is very rare. Previously reported cases of a middle ear adenocarcinoma are originated from an endolymphatic sac. In these cases, the tumor lies between the middle ear and the posterior cranial fossa, because the endolymphatic sac exists anterior to Trautmann*s triangle within the dura in the posterior cranial fossa. We have experienced a slowly progressive middle ear tumor which finally extended into the middle cranial fossa. A patient was a 50-year-old female. The lesion caused her right facial palsy two times in *87 and *96. At both times, the tumor and surrounding granulation were surgically removed in order to decompress the facial nerve. An atypical cell was observed by a pathological study, but it did not suggest enough evidences to be a malignant tumor. However, the MR image in October *97 showed the mass in the middle ear extending into the middle cranial fossa with enhancing the attached dura which suggested an intracranial invasion. Since the malignancy was strongly indicated from the clinical course, we decided to dissect her middle ear mass with a combination of transotic and supralabyrinthine approaches. We have removed the whole mass with a partial resection of the temporal bone and the middle cranial fossa dura. Her facial nerve was sacrificed by this procedure. An adenocarcinoma was finally diagnosed from the specimens by the operation.

Abstract Otology 2000 C14-4

Ming Zhang MD, PhD (1), Ugo Fisch MD (2)

(1) House Ear Institute USA-Los Angeles CA
(2) ORL-Klinik Universitätsspital CH-Zürich

Six temporal bones (3 in large and 3 in small head size) were dissected to study the anatomic landmarks of supralabyrinthine and extended middle fossa approaches, the space gain through the supralabyrinthine approach, the special relationship between the superior semicircular canal and internal auditory canal. The space gain was obtained by removing bones above the tegmen tympani and supralabyrinthine region. The space gain at valley between the labyrinthine segment of the facial nerve and superior ampulla are essential to reduce the dural elevation compared to other approaches. The space to reach the singular nerve and jugular bulb is limited by endolymphatic duct in the extended approach. The variation of the structures situated posterior to internal auditory canal is much less than those anterior to it. Our data confirm that the superior semicircular canal is a reliable landmark to locate the internal auditory canal. Head size and age determine the anatomical variation of the area anterior to internal auditory canal. A new method using lengths to determine the angle in presence of narrow and complicated topographic space between superior semicircular canal and internal auditory canal is proposed.