Vol.13: ED self-check Part-3

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【ED self-check Part-3】


For the men who have recently been concerned about not getting a sufficient erection or getting a weaker erection compared with when they were young, or unevenness of erection depending on physical condition, why don’t you try the ED self-check? Like every other disease, early detection and prompt treatment are also essential for ED.
The severity of the ED symptoms are various as there are some men who suffer from comparatively mild symptoms, such as only sometimes having problems with getting an erection or losing hardness during sexual intercourse to the others who suffer from serious symptoms such as not getting an erection at all. To know the severity by using the ED self-check is useful when choosing an ED curative and objectively evaluating the improvement after starting the medication.
The ED evaluation methods which are internationally used include the followings.

●International Index of Erectile Function
●Erection Hardness Score
●Nocturnal penile tumescence (NPT) stamp test
●Male Sexual Health Questionnaire (MSHQ)
●Golombok-Rust Inventory of Sexual Satisfaction (GRISS)
●Brief Male Sexual Function Inventory (BMSFI)

In this column, we will introduce the Nocturnal Penile Tumescence (NPT) Stamp Test.
Nocturnal penile tumescence (NPT) stamp test
As I explained in a previous column, “Not getting an erection when waking up” is a warning signal of ED, for the healthy men, the phenomenon which is called “nocturnal penile tumescence” occurs approximately 4-8 times during one night. This erection phenomenon which occurs during the REM sleep, is caused due to the seesaw balance between two kinds of automatic nerve systems (sympathetic and parasympathetic nerve). “Getting an erection in the morning” is the last of the “nocturnal penile tumescence” cycles before waking up.
The Nocturnal penile tumescence (NPT) stamp test is to examine if the men are getting erections during asleep. In the case they find out they are getting sufficient erections during asleep, it can be considered as they have no major problem with penile anatomical components, such as nerves, blood flow and vascular smooth muscle which relate to the erection. Also, because getting an erection during asleep hardly has anything to do with mental influences, most of the cases where men who don’t get sufficient erection during sex, but can get a sufficient erection while sleeping, are possibly caused by mental factors – so-called ideogenetic ED.
On the other hand, in the case of not only getting no erection when having sexual intercourse but also not getting any erection during asleep, although there is still a possibility of ideogenetic ED, this it’s more likely to be organicus ED. In the case of ED which is caused by diabetes, arteriosclerosis, striction of penile artery and thrombus blockade, surgery and injury, so-called organicus ED, these are more likely to cause serious cases, so then there is more possibility that the ED curative won’t work sufficiently even with the strongest dosage.
In this way, getting an erection during asleep can be not only a tool to diagnose between ideogenetic ED and organicus ED, but also it be an indication to gauge the effect and dose of ED curatives.

A strip of four to five postage stamps is used for each test. The man needs to wear brief-type undershorts that have a fly. Place the penis through the fly, leaving most of the pubic hair against the body. Wrap the strip of stamps snugly around the shaft of the penis. The stamps need to overlap so the overlapped stamp can be moistened to seal the ring. When the stamp has dried, carefully place the penis back inside the shorts and wear them while sleeping (Also, special gauge for this is available at a shop for about 1,000 yen). In the morning, check to see if the stamp ring has been broken along the perforations. If the tearing of the stamps awakens the man during the night, check for an erection and how rigid the erection is.

Prepare the stamps or the special measuring equipment. Do not drink alcohol or take a sleeping drug or sedative medication for at least 2 days before the test.

【On the occasion of the test implementation】
The stamps or the measuring equipment may feel unusual. The test should be done for 3 nights where comfortable, uninterrupted sleep is achieved. Also because a nocturnal penile tumescence isn’t sometimes seen every night even for healthy man, the test is required to be done for 3 days at a minimum.

If the stamp ring is broken, it means that the nocturnal penile tumescence occurred and if you have erection problems while you are awake this may be the result of a psychological cause, so-called ideogenetic ED.
If the stamp ring isn’t broken it means that the nocturnal penile tumescence didn’t occur and the erection problem may be related to, the penile anatomical components, such as nerves, blood flow and vascular smooth muscle, this is so-called organicus ED.

【Meaning of the test】
Even though this is a classic testing method to distinguish between ideogenetic (functionality) ED and organicus ED, it is still beneficial as the information about the cause of ED in patients can be detected comparatively easily. As for the ideogenetic ED, ED curative with low dosage could be enough to get sufficient effect. However, in the case of organicus ED, it is often difficult for the ED curative to work sufficiently and high doses tend to be required. Also, in case of the organicus ED, there is a possibility that blood vessels in the heart and brain have similar faults, too. Therefore, when the cause could be the organicus ED, we recommend you to see a doctor for inspection of the cardiovascular and cerebrovascular system.


【Supervisor of this article】

Ken Takemori, MD. An anesthesiologist and Director of Shibuya 3rd Block Clinic.


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