the association of nonsyphilitic interstitial keratitis and audiovestibular involvement was first reported in 1934 by mogan and baumgartner . cogan s syndrome , the presence of interstitial keratitis is necessary , the term  atypical cogan s syndrome is used when other types of inflammatory eye disease , including conjunctivitis , uveitis , scleritis , and choroiditis are associated with the vestibuloauditory abnormalities . in many cases , the symptomatology is not only restricted to the eyes and the ears but also other organs , thus resembling systemic vasculitis in one third of the patients . the most common symptoms are cardiovascular , musculoskeletal , neurological , gastrointestinal , and mucocutaneous . positron emission tomography ( pet ) with 2-deoxy-2-[f]fluoro - d - glucose ( fdg ) is becoming increasingly important in diagnosis , staging , and therapy monitoring in clinical oncology and has recently been used in the diagnosis of infectious diseases with elevated intracellular glucose metabolism . activated inflammatory cells have been shown to overexpress glucose transporters and to accumulate increased amounts of glucose and structurally related substances such as f18-fdg [ 4 , 5 ] . therefore fdg - pet is also introduced as a diagnostic means to assess involvement in large vessel vasculitis . in this report , we report the use of fdg - pet / computed tomography ( ct ) scanning in the diagnosis of cogan s syndrome . a 60-year - old caucasian woman was admitted to the hospital with a 4-month history of excessive fatigue , coughing , anorexia and weight loss , night sweats , and atypical chest pain . she experienced headaches and ear pain and hearing loss for over the last month , mainly on the left side , and felt sometimes dizzy . she was not known with any allergies . for her hypothyroidism ( multinodular goiter ) , she used thyrax ( l - thyroxine)150  mcg once a day . physical examination revealed a pulse of 104 , and bloodpressure was 125/85  mmhg and the temperature 37.1c . no lymphadenopathy was detected and no scalp tenderness or decreased pulsation at the temporal arteries was noted . laboratory tests revealed an erythrocyte sedimentation rate ( esr ) of 51  mm / h and c - reactive protein ( crp ) of 53  mg / l . l ( < 10 ) , and tests for antinuclear facor and double - stranded dna antibodies were negative . a test for anti - neutrophil cytoplasmic antibody ( anca ) appeared to be myeloperoxidase positive with p - anca specificity . the urine gave a negative test for protein , and the sediment contained no white cells , red cells , or casts in the urine . initially arteritis temporalis was suspected , but doppler ultrasonography of the temporal arteries showed no abnormalities . subsequently , a pet / ct was performed , which showed pathological uptake in the wall of the aortic arch . more intens pathological uptake was seen at the beginning of the aorta descendens in the lateral wall , most likely a sign of perivascular inflammation . a magnetic resonance imaging ( mri ) scan of the cerebrum showed abnormalities suspicious for bilateral mastoiditis , possibly as a consequence of bilateral otitis media . 1a transverse fused pet / ct slice showing pathological uptake in the wall of the aortic arch and particularly in the lateral wall and perivascular space adjacent to the truncus pulmonalis ( suv max 11.9 ) . b follow - up pet / ct 3  weeks later , after treatment with methylprednisolon i.v . and prednisolon orally , showing clearly decreased uptake in the aortic arch ( suv max 4.3 ) . c second follow - up pet / ct 6  months later , while patient was in a stable condition with methotrexate and low - dose prednisone . again , high pathological uptake in the aortic arch with higher intensity in the lateral wall and perivascular space adjacent to the truncus pulmonalis ( suv max 12.9 ) a transverse fused pet / ct slice showing pathological uptake in the wall of the aortic arch and particularly in the lateral wall and perivascular space adjacent to the truncus pulmonalis ( suv max 11.9 ) . b follow - up pet / ct 3  weeks later , after treatment with methylprednisolon i.v . and prednisolon orally , showing clearly decreased uptake in the aortic arch ( suv max 4.3 ) . c second follow - up pet / ct 6  months later , while patient was in a stable condition with methotrexate and low - dose prednisone . again , high pathological uptake in the aortic arch with higher intensity in the lateral wall and perivascular space adjacent to the truncus pulmonalis ( suv max 12.9 ) after placing inner ear tubes , her hearing loss improved only little . therapy was started with three cycles of 1,000  mg methylprednisolon intravenously and later 60  mg prednisolon daily orally . as a consequence of the high doses of steroids , risedronate and calcium supplementation were started , and also methothrexate was added for the reason of its steroid - sparing effect .  atypical cogan s syndrome was diagnosed on the basis of sensorineural deafness with improvement on steroids and large - vessel vasculitis of the aortic arch . a follow - up pet / ct investigation 3  weeks later showed clearly decreased uptake in the aortic arch , especially a dramatic decrease at the location of the focal uptake in the lateral wall , compared to the first pet / ct . esr and crp after 2  weeks of therapy were , respectively , 11  mm / h and < 2 six months later , she was in a stable condition with methotrexate and low - dose prednisone , and her esr , crp , and white cell count were now , respectively , 24  mm / h , 14  mg / l , and 13.7.10  l. a third pet / ct showed higher pathological activity , compared to the first pet / ct , in the wall of the aortic arch and in the perivascular space adjacent to the truncus pulmonalis ( the suv max was12.9 compared to the suv max of 11.9 of the first pretherapy pet / ct investigation ) . consequently , the dose of methothrexate and prednisone were both increased to 20  mg / day . the etiology of cogan s syndrome is unknown ; a minority of patients have rheumatoid factor , antinuclear bodies , and diminished complement levels . cardiac involvement during the course of cogan s syndrome is , above all , aortic insufficiency . it is a severe complication that may require valve replacement , without which left ventricle involvement insufficiency develops , which can be fatal [ 9 , 10 ] . standard diagnostic modalities such as biopsy , angiography , ultrasound , and mri are commonly unable to demonstrate the full extent of vascular involvement in large - vessel vasculitis . pet investigations might play an important role here as large - vessel f18-fdg uptake is positively correlated with the level of acute phase reactant markers in patients with large vessel vasculitis . in a study of 18 patients with takayasu s arteritis , the f18-fdg - pet examination showed a sensitivity of 92% and a specificity of 100% . this is , to the best of our knowledge , the first report of cogan s syndrome diagnosed by the use of fdg - pet / ct scanning . this case report is also supportive in the hypothesis that with pet , the inflammatory activity of large - vessel vasculitis is more accurately assessed compared to laboratory acute phase parameters . the ct component of pet / ct is useful in the precise anatomical localization of the pet abnormalities and may provide information about changes in the wall structure or luminal flow . the conclusion seems justified that f18-fdg - pet / ct is helpful in risk assessment of large - vessel vasculitis , as it provides intrinsically fused morphologic and functional data in a single examination .
we report on the case of a 60-year - old woman with complaints of fatigue , coughing , anorexia , atypical chest pain , recurrent fever , and also ear pain and hearing loss . 
 a test for anti - neutrophil cytoplasmic antibody ( anca ) was myeloperoxidase positive with p - anca specificity . 
 laboratory acute phase parameters were increased . 
 a 2-deoxy-2-[18f]fluoro - d - glucose positron emission tomography / computed tomography investigation showed pathological uptake in the aorta ascendens , with no other involvement of the large vessels . 
 after therapy with methylprednisolon intravenously and later prednisolon orally with methothrexate , her general condition and hearing loss improved both subjectively and objectively . 
 atypical 
 cogan s syndrome was diagnosed on the basis of sensorineural deafness with improvement on steroids and large - vessel vasculitis of the aortic arch .