To describe 8 additional cases of seminal vesicle cyst associated with renal agenesis, an uncommon condition arising from anomalies occurring during embryonal development of the genitourinary system, and to analyze the utility of the different diagnostic imaging techniques.A retrospective study was conducted on 8 patients to determine the diagnostic possibilities of US (abdominal/transrectal), CT, MRI, urography, cystourethrography and cystoscopy. Transvesical percutaneous punction and deferentography, which permit diagnosis of blind-ending ureter, were utilized in two patients.75% were left-sided and the age at presentation was generally between 25 to 45 years. The clinical features were related with irritative voiding symptoms, perineal discomfort and ejaculatory disorders. Treatment was based on the clinical features; 3 patients underwent resection via the abdominal retrovesical approach and 5 patients were treated conservatively.Congenital seminal vesicle cyst may not be as uncommon as it is presumed to be and should be suspected in patients with solitary kidney and voiding disorders. The findings on pelvioabdominal US may suffice to suspect this condition. Although many diagnostic imaging techniques are available, blind-ending ureter can only be diagnosed by transvesical or transrectal percutaneous punction and deferentography. Treatment of symptomatic cases is by surgery, although conservative treatment is utilized more frequently.