Presentation
Swollen left leg ? venous obstruction. Normal duplex ultrasound. No urinary symptoms.
Patient Data
Very large bilobed cystic mass arising in the pelvis with gross hydronephrosis and hydroureter right > left. Mass has 2 lobes: on the left is thick-walled and trabeculated (containing a calculus) consistent with the bladder and on the right is thin-walled and communicates with the bladder via a defect in the wall = pseudodiverticulum. Left leg swelling is due to extrinsic compression of the left iliac veins.
Rpt CT following insertion of urinary catheter at 2100 hours
Following catheter insertion and 5 hour delay the mass has "disappeared" with 4 liters of urine in the catheter bag. The bladder is collapsed and markedly thick-walled. Note contrast in the dilated left renal collecting system down to the bladder, but poorly functioning right kidney due to chronic backflow obstruction.
Cause is presumed to be bladder outlet obstruction (possible due to the prostate or other urethral stricture). Note the so-called stasis bladder stone.
Case Discussion
Despite the gross findings, the patient was said to be asymptomatic with regard to the urinary tract. This shows how bladder outlet obstruction can slowly "creep up" on the patient without pain, i.e. chronic bladder retention.
The bladder does not have the findings of a neurogenic bladder (i.e. Christmas tree configuration), the other major cause of painless enlargement of the bladder.