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he had begun to experience visual problems 8 months earlier , which rapidly deteriorated in the last 2 months .
fifteen months later , metastatic disease was discovered in his sternum and he received iodine-131 therapy .
his visual acuity was light perception in the right eye and 20 / 25 in the left eye .
microcystic corneal edema , a fixed and dilated pupil , and rubeosis iridis were found in the right eye .
there was total serous retinal detachment and the intraocular pressure was 45 mmhg ( applanation ) .
ocular ultrasonography demonstrated a single choroidal lesion with a basal diameter measuring 11 mm and a thickness of 6 mm in the right eye ( fig .
the right eye was enucleated , as there were no prospects of recovering useful vision .
a dark , well - encapsulated scleral nodule was noted over the enucleated globe ( fig .
a month later , the patient 's visual acuity in the left eye decreased to 20 / 200 with the new development of a solitary , reddish - pink choroidal mass that measured 6  4.5 mm in basal dimensions and 1.5 mm in thickness , superior to the fovea and within the temporal vascular arcades ( fig .
this tumor was treated with a single session of transpupillary thermotherapy using a 0.5 mm spot size , 500 mw power , and 29 overlapping spots each lasting 45 seconds .
six weeks later , the tumor in the left eye totally disappeared without any improvement in the patient 's visual acuity ( fig .
evidence for widespread metastatic involvement of the lungs was confirmed a month later and he expired from respiratory complications .
histopathological examination of the eye revealed that the choroidal tumor was composed of papillary excrescences and cystic spaces ( fig .
the sclera was eroded in full thickness and tumor cells gained access into the sub - tenon 's space .
hematogenous distant metastases occur in only 10% of patients , mainly to the lungs , bones , and brain .
ocular metastasis is distinctly unusual and when present , the orbit is more commonly affected than the intraocular tissues .
uveal metastatic thyroid carcinoma was found in patients who had their primary cancer diagnosed and treated for an average of 9.9 years ( range , 4 to 30 years ) [ 4 - 9 ] . in 2 cases ,
reported ocular signs and symptoms included a sudden loss of visual acuity , loss of color discrimination , visual field defects , and light flashes [ 3 - 9 ] .
the majority of these patients had a solitary , amelanotic , orange - yellow choroidal mass sometimes associated with serous or hemorrhagic retinal detachment [ 3 - 7,9 ] .
extraocular extension , very similar to our case , was found only once , in a blind and painful eye . because a very limited numbers of patients have been reported , no data exist describing the best and most effective treatment of this condition .
external beam radiotherapy , i ablation therapy and enucleation have been employed based on the extent of the tumor , the potential for visual improvement and the systemic status of the patient [ 3 - 9 ] . in our patient ,
transpupillary thermotherapy resulted in satisfactory regression of the solitary choroidal metastatic tumor in the left eye .
here , we present the case of a patient with bilateral choroidal metastases with extraocular extension in one eye . 
 metastasis of papillary thyroid carcinoma to the uvea is extremely rare , with only 6 patients reported in the literature . 
 a 62-year - old man with a prior history of papillary thyroid carcinoma suffered the rapid loss of vision in his right eye . 
 he had neovascular glaucoma , total retinal detachment , and a solitary choroidal mass . 
 a month later , his left visual acuity also decreased because of a small macular choroidal mass . 
 the right eye was enucleated and a nodular lesion over the sclera representing extraocular extension was observed . 
 this tumor and the intraocular lesion were composed of papillary excrescences and cystic spaces and stained positively for thyroid transcription factor 1 and thyroglobulin , all confirming the diagnosis of metastatic papillary thyroid carcinoma . 
 the tumor in the left eye was successfully treated with diode laser transpupillary thermotherapy . 
 the patient expired within a month as a result of widespread pulmonary metastases . 
 papillary thyroid carcinoma may metastasize to the uvea bilaterally , cause rapid visual function loss , erode the sclera , and may extend outside the globe similar to choroidal melanoma . 
 this aggressive ocular involvement was associated with a dismal prognosis in our patient .