Utricle cyst (prostatic utricle cyst) is a congenital midline cystic lesion resulting from cystic dilatation of the prostatic utricle (utriculus prostaticus). The prostatic utricle is a rudimentary remnant of the Müllerian (paramesonephric) duct in males and exists as a small blind-ending pouch on the verumontanum. The utricle cyst is located at midline at verumontanum level and does NOT extend above the prostate — this feature is the key distinguishing criterion from Müllerian duct cyst. Usually small (<10-15 mm), asymptomatic, and discovered incidentally on mpMRI. May be associated with hypospadias and other urogenital anomalies. In PI-RADS v2.1, it is considered a benign finding.
Age Range
15-40
Peak Age
25
Gender
Male predominant
Prevalence
Rare
The prostatic utricle is the last remnant of the Müllerian duct in males — homologous to the uterus and vagina in females. It exists as a 3-6 mm blind-ending pouch on the verumontanum, near the opening point of the ejaculatory ducts. Cystic dilatation of the utricle develops from orifice obstruction or congenital ectasia. The utricle cyst has direct anatomical relationship with ejaculatory ducts and may contain spermatozoa on aspiration — this feature is important in differential diagnosis from Müllerian duct cyst. In hypospadias, cryptorchidism, and intersex conditions, the utricle may be larger and more prominent — insufficient androgen effect cannot complete Müllerian duct regression. On imaging, it appears T2 hyperintense because it contains serous/seminal fluid. Absence of enhancement results from the avascular nature of the simple epithelial lining. Remaining within the prostate and not extending above it is because the utricle is anatomically a structure confined to the verumontanum.
The most important diagnostic feature of utricle cyst is that it does NOT extend above the prostate. On sagittal T2 MRI, the cyst remains entirely within prostate boundaries — this feature definitively differentiates from Müllerian duct cyst (which extends above prostate). Both cysts are midline and T2 hyperintense, but the extension difference is the reliable distinguishing criterion. Utricle cyst is confined to the verumontanum because anatomically the prostatic utricle is a pouch terminating on the verumontanum — embryologically the most distal end of the Müllerian duct.
On T2-weighted images, markedly hyperintense cystic lesion at midline, at verumontanum level, posterior to prostate. Well-defined, thin-walled, homogeneous fluid content. Does NOT extend BEYOND the superior border of the prostate — remains within the prostate. Usually round or oval morphology, size <10-15 mm. Large utricle cysts (>15 mm) are rare and require urogenital anomaly investigation.
Report Sentence
Midline T2 hyperintense cystic lesion at verumontanum level, confined within the prostate, consistent with utricle cyst.
Usually hypointense on T1-weighted images — simple serous/seminal fluid content. May be hyperintense on T1 with proteinaceous or hemorrhagic content. Hemorrhagic utricle cyst may clinically present with hematospermia.
Report Sentence
Utricle cyst showing hypointense signal on T1-weighted images, consistent with simple fluid content.
No enhancement on contrast-enhanced sequences — simple epithelial lining is avascular. Minimal enhancement may be seen in cyst wall. Absence of enhancement differentiates from solid lesions and prostate cancer.
Report Sentence
Utricle cyst showing no enhancement on contrast-enhanced sequences, consistent with benign cystic structure.
No diffusion restriction on diffusion-weighted images. High signal on ADC map — free diffusion. Diffusion restriction may be seen in infected cyst (purulent content).
Report Sentence
Utricle cyst showing no diffusion restriction, with high signal on ADC map confirming simple cystic structure.
On TRUS, small anechoic or hypoechoic cystic lesion at midline posterior prostate. Localized at verumontanum level. Posterior acoustic enhancement. Usually <10 mm in size. May be discovered incidentally during prostate biopsy or BPH evaluation.
Report Sentence
Small anechoic cystic lesion at midline in posterior prostate on TRUS, consistent with utricle cyst.
Criteria
No associated urogenital anomaly. Small size (<10 mm). Asymptomatic, incidental finding. No follow-up needed.
Distinct Features
Small, asymptomatic, isolated, no clinical significance
Criteria
Associated with hypospadias, cryptorchidism, or intersex condition. Usually larger utricle (>15 mm). May be diagnosed in childhood. Pediatric urology evaluation required.
Distinct Features
Urogenital anomaly, large size, childhood diagnosis, androgen insufficiency
Criteria
Hematospermia, pelvic pain, dysuria, recurrent urinary infections. Large cysts may cause bladder neck obstruction. Risk of infection (utricle abscess). Transurethral marsupialization or laparoscopic excision options.
Distinct Features
Symptomatic, hematospermia, infection, surgical indication
Distinguishing Feature
Müllerian duct cyst is midline BUT extends ABOVE the prostate (pear-shaped, supraprostatic extension). Utricle cyst remains WITHIN the prostate and does not extend above. Extension difference on sagittal T2 MRI is the definitive distinguishing criterion. Müllerian cyst does not contain spermatozoa, utricle cyst may contain them.
Distinguishing Feature
Prostatic retention cyst is BPH-associated, usually in transitional zone, paramedian location, and may be multiple. Utricle cyst is congenital, single, midline, and at verumontanum level. Retention cysts are scattered small cysts among BPH nodules.
Distinguishing Feature
Seminal vesicle cyst is LATERALLY located and follows seminal vesicle anatomy. Utricle cyst is MIDLINE and located at verumontanum level in posterior prostate. Lateral vs midline differentiation is easily made on axial T2 MRI.
Urgency
routineManagement
conservativeBiopsy
Not NeededFollow-up
no-follow-upAsymptomatic utricle cysts are benign findings requiring no treatment or follow-up. Benign finding in PI-RADS v2.1 — does not affect prostate cancer screening. In mpMRI reports, midline location and confinement within the prostate should be stated, differentiating from Müllerian duct cyst. Symptomatic utricle cysts (hematospermia, urinary obstruction, recurrent infection) may be treated with transurethral marsupialization or laparoscopic excision. When a large utricle cyst is found, urogenital anomaly investigation (hypospadias, cryptorchidism) is recommended.
Utricle cysts are usually asymptomatic and clinically insignificant. They may rarely be associated with recurrent urinary infections or hemospermia. They may be associated with hypospadias and other genital anomalies. Treatment is rarely needed.