Penile Non-imaging and Imaging Flashcards
What are the capabilities of penile non-imaging and imaging?
Determine whether impotence is related to peripheral vascular insufficiency
Limitations of penile non-imaging and imaging:
- High level of anxiety or antagonism
- Duplex needed for velocities and anatomic conditions
- Sensitivity to injectable medication; and/ or anticoagulation therapy may prevent use of the injection component
What is patient positioning for penile imaging?
supine
Physical principles for penile imaging:
- Doppler previously described
- Plethysmographic techniques
- Duplex scanning principles
Technique for penile non-imaging:
- Doppler velocity signals obtained bilateral (CFA, PTA, DPA)
- Appropriate cuffs placed on upper arms and ankles
- Penile pressures obtained with doppler or PPG as the “end point detector” probe placement: lateral and ventral.
- Penile plethysmographic waveforms obtained
What cuff is used for penile non-imaging?
205cm x 12.5 cm
What obstruction could possibly affect penile arterial flow?
Poor arterial inflow due to LE proximal onstruction
Penile / Brachial Index:
Normal -
Marginal -
Abnormal -
Normal = > 0.75
Marginal = 0.65 - 0.74
Abnormal = < 0.65
Reduced penile pressure is highly suggestive of:
more proximal arterial disease (aortic-iliac: internal iliacs)
What doe abnormal plethysmographic tracings show?
marked reduction in amplitude
What transducer do you use for penile imaging?
7 to 10 MHz transducer
Prior to injection of medication, which arteries are measured?
cavernous arteries (AP) in transverse
PSV, EDV obtained
Where is the medication injected?
lateral aspect, proximal shaft of penis
(to induce erection)
When are the cavernous arteries re-measured?
1-2 minutes post-injection
What is the last step of penile imagin?
Dorsal vein flow velocity is measured
How long can an erection last post medication before the patient needs to contact urology to reverse priaprism?
3 hours
What are the normal outcomes of penile imaging?
- Diameter of cavernous arteries should increase post-injection
- PSV measurements should increase
- Dorsal vein velocities should not increase
What is a normal range of PSV?
30 cm/sec or higher
- anything less is abnormal
What does an increase in the dorsal vein suggest?
venous leak
What is a normal and abnormal measurement in the dorsal vein?
Normal - < 3 cm/sec
Abnormal - >20cm/sec
