carcinoma of the prostate is a common condition , with over 21 000 cases and over 10 000 deaths every year in the united kingdom alone .
we describe two patients with known carcinoma of the prostate who presented with visual disturbance and papilloedema on examination .
the first patient was a 76-year - old gentleman who presented to the urology service complaining of a poor stream .
he re - presented to the urology service 30 months later with a serum psa of 378 g / l with macroscopic haematuria .
a trans - rectal biopsy of the prostate was performed and poorly differentiated adenocarcinoma of the prostate was diagnosed .
an mri scan was performed , which showed bony metastases in the occipital bone and oedema in the cerebellum ( figs 1 and 2 ) .
the slightly hyper - intense signal in the superior sagittal sinus indicates that the thrombosis is between 5 and 15 days old and is due to the presence of methaemoglobin .
the patient responded well to 20 gy ( in five fractions ) of radiotherapy , delivered to the occipital region .
figure 1 
 t2w sagittal image of patient 1 , showing metastases in the occipital bone and oedema of the cerebellum.figure 2 
 t2w axial image of patient 1 , showing mixed signal in the sagittal sinus compatible with thrombosis .
after treatment of the metastases with radiotherapy , follow - up imaging showed a return of a normal signal void . 
 t2w sagittal image of patient 1 , showing metastases in the occipital bone and oedema of the cerebellum . 
 t2w axial image of patient 1 , showing mixed signal in the sagittal sinus compatible with thrombosis .
after treatment of the metastases with radiotherapy , follow - up imaging showed a return of a normal signal void .
the second patient was a 62-year - old gentleman who was admitted to hospital with a history of recent onset of headaches , nausea , nocturia and macroscopic haematuria .
positive findings on examination included bilateral papilloedema and a markedly ataxic gait with cerebellar ataxia .
isotope bone scanning showed bony metastases in the thoracolumbar spine , the pelvis and the base of the skull . computed tomography ( ct ) of the brain did not demonstrate cerebral metastases but mri scanning did reveal bony metastases in the occiput ( fig .
venous infarcts in the occipital lobes adjacent to the superior sagittal sinus were also demonstrated ( fig .
figure 3 
 t2w axial image of patient 2 , showing metastases in the occipital bone and iso - intense signal in the occluded sagittal sinus .
note the fluid around both optic nerves.figure 4 
 mrv ( 2d tof ) of patient 2 showing thrombus in the superior sagittal sinus.figure 5 
 coronal t1w image of patient 2 demonstrating high signal adjacent to the superior sagittal sinus compatible with haemorrhage . 

t2w axial image of patient 2 , showing metastases in the occipital bone and iso - intense signal in the occluded sagittal sinus .
mrv ( 2d tof ) of patient 2 showing thrombus in the superior sagittal sinus . 

coronal t1w image of patient 2 demonstrating high signal adjacent to the superior sagittal sinus compatible with haemorrhage .
the patient was commenced on cyproterone acetate and received 30 gy to the skull in 10 fractions over 14 days .
papilloedema has been described in prostate carcinoma due to transverse sinus thrombosis , but this was a result of dural metastases at the torcula and not in the bone of the skull vault .
bony metastases in the optic canal have also been described , causing painless visual loss .
mri is effective at showing both bony metastases in carcinoma of the prostate and is the imaging modality of choice for cerebral venous sinus thrombosis .
intravenous contrast - enhanced ct scanning may show filling defects in the superior sagittal sinus , but mri is more sensitive in the detection of superior sagittal thrombosis and venous oedema and of bone metastases .
we would suggest that in a patient with visual disturbance , who is known to be suffering from a malignancy that may spread to bone , mri is the imaging modality of choice and the venous sinuses should be examined with mrv at the time of imaging .
 carcinoma of the prostate is a common condition and often spreads to bone . 
 we describe the imaging findings in two patients with known carcinoma of the prostate who presented with visual disturbance ( both had papilloedema on examination ) . 
 mri showed occipital bone metastases and superior sagittal sinus thrombosis . 
 we suggest that mri is the imaging modality of choice in patients suffering from prostate cancer who have visual disturbance and that mrv sequences should be included to detect venous sinus thrombosis . 
Introduction
Case 1
Case 2
Discussion