MRI and its role in the evaluation and surgical decision making in patients with challenging IPP presentations: descriptions of MRI findings and algorithm for patient management.
Study Type - Diagnostic (case series) Level of Evidence 4 What's known on the subject? and What does the study add? It is known that magnetic resonance imaging (MRI) is safe and effective for imaging patients with inflatable penile prostheses (IPPs). Previous series have reported results of MRI for imaging series of patients with IPPs. The impact on management in particular with regard to salvage procedures is not well defined. This study represents the largest known experience with MRI evaluation of IPPs. This also provides an algorithm that assists with decisions regarding utilization of MRI and treatment planning based on results.


OBJECTIVE
• In some patients who undergo placement of an inflatable penile prosthesis (IPP) the device may function inadequately. We describe the use of magnetic resonance imaging (MRI) for anatomical localization and detection of prosthesis malrotation, angulation, displacement and erosion in IPPs with equivocal clinical examination.


METHODS
• We prospectively performed MRI by a defined protocol including T1-weighted imaging, and transaxial, sagittal and coronal fat-saturated fast spin-echo T2-weighted imaging in both deflated and inflated states to evaluate patients seen at our referral centre for IPP-related complaints. • We retrospectively reviewed 32 such MRI studies performed as a supplement to clinical examination between 2000 and 2008.


RESULTS
• Of 32 cases, 75% (24/32) underwent surgical intervention. Of these, 45% (11/24) underwent device salvage procedures including cylinder revision in 33% (8/24), cylinder replacement in 8% (2/24) and pump replacement in 4% (1/24). • MRI was most useful for determination of surgical approach in those with abnormal physical examination, and for justification of either surgical or expectant management in those with indeterminate physical examination.


CONCLUSIONS
• MRI is safe and effective for imaging genitourinary prostheses. • We found MRI to be a valuable adjunct for evaluation of IPP-related complaints when clinical examination is equivocal as it detected a variety of prosthetic and corporal abnormalities and impacted management decisions regarding observation, replacement or device salvage procedures. • We provide technique, results and an algorithm that can be beneficial in this complex subset of patients.
Department of Urology Radiology, Mayo Clinic, Rochester, MN 55905, USA. efmcphail@gmail.com
E Fred
EF
McPhail
Ajay
A
Nehra
Bryan C
BC
Bruner
Akira
A
Kawashima
Bernard F
BF
King
Bohyun
B
Kim
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D003657:Decision Making; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D015917:Penile Prosthesis / Q000592:standards*; D010808:Physical Examination / Q000379:methods; D011446:Prospective Studies; D011475:Prosthesis Failure; D012189:Retrospective Studies