How Is Curvature Measured in Peyronie's Disease? Examination, Photographs and Penile Doppler

At the centre of the treatment decision in Peyronie's disease lies a single question: how much curvature is there? Whether non-surgical approaches will be tried, whether surgery comes into consideration and which surgical technique is appropriate all depend largely on this measurement.

Most patients, however, arrive at the consultation with an estimate of their own. The sentence "I think it's about 40 degrees" is heard very often, and it usually differs markedly from the actual measurement. This article explains how curvature is measured, why particular investigations are requested and why the measurement must be made on an erect penis.

Why is measurement so decisive?

In Peyronie's disease, measurement is an input to the treatment plan. The following decisions rest directly on it:

• Whether the curvature prevents intercourse
• Whether it is meaningful to try non-surgical options
• Which technique is appropriate if surgery comes into consideration
• Whether, taking erectile status into account, a prosthesis should be considered
• Whether the disease is progressing during follow-up

Measurement is also the basis of communication with the patient. In some patients the curvature is perceived as far more pronounced than it actually is; in others, an advanced curvature is underestimated. A concrete measurement corrects perception at both extremes.

Why is measuring a flaccid penis misleading?

In Peyronie's disease, curvature appears during an erection. The hardened tissue known as a plaque prevents that area from expanding as much as the rest during an erection, and the penis bends towards that side. When the penis is flaccid, this mechanism is not in play.

An assessment made on a flaccid penis therefore gives no reliable information about the degree of curvature. During examination, the location, hardness and size of the plaque can be assessed with the penis flaccid; but the angle must be measured on an erect penis.

For the same reason, observations a patient makes at home with a flaccid penis are misleading. A frequent situation in the clinic is that a patient describes a pronounced curvature when flaccid, while the measurement in the erect state turns out differently.

What is looked at during examination?

The initial assessment begins with a detailed conversation and examination. The following are covered at this stage:

• History: When the curvature began, whether it has increased, whether there is pain and whether it has changed in recent months.
• The status of pain: The presence of pain is among the findings suggesting the active phase of the disease; pain having resolved is among the indicators of transition to the stable phase.
• Palpation of the plaque: The location, number, hardness and borders of the plaque are assessed. This examination is performed with the penis flaccid.
• Penile length: Stretched length is recorded; this value matters particularly in surgical planning.
• Erectile status: Whether erectile dysfunction accompanies the curvature is enquired about. This is among the most critical headings determining the surgical technique.
• Effect on intercourse: Whether the curvature makes intercourse difficult or prevents it.

Why is a patient photograph requested?

In a Peyronie's assessment, a patient may be asked to photograph the erect penis at home. Some patients find this request odd; yet it has a practical rationale: a natural erection cannot always be achieved during examination, and curvature is visible only during an erection.

When a photograph is requested, the guidance given is generally as follows:

• Take it at full erection
• Take it from at least two angles, from above and from the side
• Ensure the penis fits within the frame and is not cut off
• Take it in good light and in focus

These images show the direction and approximate degree of the curvature, and allow comparison during follow-up. A patient photograph does not replace the measurement made in the clinic; it complements it. It should also be stated clearly to the patient that these images fall within patient privacy and are handled on the basis of confidentiality.

Measurement with an induced erection

The most reliable measurement is the one made in the clinic after a controlled erection has been achieved. For this purpose an erection is produced by injection into the penis, and the curvature is assessed in that state.

What this method provides is as follows:

• Objective measurement of the angle: The degree of curvature is recorded with the aid of a goniometer.
• Direction of the curvature: Whether it is upward, downward, lateral or in a combined direction is determined.
• Visualisation of deformities: Findings that appear only during an erection, such as an hourglass appearance, a hinge effect or marked narrowing, are identified.
• Assessment of erection quality: The adequacy of the rigidity achieved becomes apparent, which influences whether a prosthesis comes into consideration.

Because situations such as an erection lasting longer than expected can occur during this procedure, it must be carried out in clinical conditions and the patient must be informed beforehand.

What does penile Doppler ultrasound show?

Penile Doppler ultrasound is an imaging method that assesses blood flow and tissue structure in the penis after an erection has been achieved. In Peyronie's disease it answers two separate questions:

• The structure of the plaque: Its location, size and whether it contains calcification become visible. The presence of a calcified plaque is among the findings that limit the effect expected from non-surgical methods.
• Vascular status: The adequacy of blood flow into the penis and the presence of venous leak are assessed.

The second heading is often as decisive as the degree of curvature in the treatment decision. In a patient with pronounced curvature but also inadequate rigidity, surgery aimed only at correcting the curvature may not address the patient's main complaint. In this group, correcting the curvature and placing a penile prosthesis within the same plan comes into consideration.

How often is the measurement repeated?

Peyronie's disease runs in two phases. In the active phase pain and change continue; in the stable phase the picture settles. A decision for surgery requires the picture to have settled.

In patients in the active phase, the measurement is therefore repeated at intervals. What is looked at during follow-up is not a single number but whether that number is changing. Pain having resolved, and no marked change being found in measurements taken a few months apart, are findings that support transition to the stable phase.

When should a doctor be consulted?

An assessment is advised in the following situations:

• A newly noticed curvature during erection
• A hard area or nodule palpable in the penis
• Pain during erection
• Curvature that has been increasing in recent months
• An hourglass appearance or marked narrowing in the penis
• Curvature making intercourse difficult or preventing it
• Weakening of erections accompanying the curvature

In Peyronie's disease, the right treatment begins with the right measurement. Assessing curvature on an erect penis, establishing the structure of the plaque and vascular status through imaging, and repeating the measurement during the active phase place the treatment decision on solid ground. Self-made estimates cannot provide that ground. Assoc. Prof. Zülfü Sertkaya practises in urology and andrology in Istanbul; assessment and treatment planning in penile curvature are carried out with individual assessment and confidentiality.

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