Penile Narrowing (Hourglass or Bottleneck Deformity)

What penile narrowing looks like

Narrowing is usually noticed only during an erection. Common patterns are:

• Hourglass deformity: a band of narrowing around the shaft, wider above and below.
• Bottleneck deformity: narrowing at one point, often near the base, with the shaft beyond it wider.
• Indentation: a dent on one side, also called a notch (see penile indentation).

Some men notice that the penis beyond the narrowed area feels floppy or bends there, a "hinge" effect that can make penetration difficult.

Causes of penile narrowing

Peyronie's disease

Peyronie's disease is the leading cause. Scar tissue forms in the tunica albuginea, the tough sheath around the erectile chambers, probably after small, often unnoticed injuries during sex. When the scar runs around the shaft, it stops that segment from expanding, causing narrowing. Features:

• a firm lump or band you can feel under the skin
• curvature toward the side of the plaque
• pain with erections in the early phase
• shortening of the penis
• erectile dysfunction in many men

Peyronie's disease affects an estimated 3 to 9% of adult men, most often between 40 and 70. It is linked with Dupuytren's contracture of the hand, diabetes, smoking and prostate cancer treatment.

The disease has two phases. The acute phase lasts roughly 6 to 18 months, with pain and a changing shape. The chronic (stable) phase follows, with a fixed deformity and usually no pain.

Narrowing at the base of the penis

• Peyronie's plaques near the base
• Scarring after penile surgery, implants or injections for erectile dysfunction
• A previous penile fracture that healed with scar
• An apparent narrowing at the base in men with excess pubic fat, which can hide part of the shaft rather than truly narrowing it

Constriction by an object

Rings, rubber bands or other objects placed around the penis can trap blood and cause swelling beyond the band and narrowing at it. This is an emergency because it can cut off blood supply.

Foreskin and skin conditions

Phimosis and lichen sclerosus can cause a tight, narrow band of foreskin. These affect the skin, not the shaft itself.

How it is diagnosed

A urologist will ask when it started, whether it hurts, whether shape is changing and how it affects sex. The exam includes feeling for plaques and measuring length. To see the deformity, the doctor may:

• review photographs of the erect penis taken at home
• give an injection that produces an erection in the clinic
• perform a penile ultrasound to locate plaques, look for calcium and assess blood flow

Treatment

Treatment is only needed if the shape causes pain or makes sex difficult.

• Observation: during the acute phase, many men wait for the condition to stabilize. Pain usually settles over time.
• Penile traction therapy: a device worn for several hours a day that can improve length, curvature and narrowing.
• Vacuum devices may help some men.
• Injections into the plaque: collagenase or verapamil, to soften the scar. Collagenase is approved for curvature in the stable phase.
• Surgery once the deformity has been stable for at least 3 to 6 months: plication (shortening the long side), plaque incision with grafting (which can correct narrowing), or a penile implant with remodeling for men who also have significant erectile dysfunction.
• Erectile dysfunction treatment with tablets often helps.

Oral supplements such as vitamin E have not been shown to work.

Frequently asked questions

What causes narrowing of the penis shaft?

The most common cause is Peyronie's disease, where scar tissue inside the penis stops part of the shaft from expanding during erection. Other causes include healing after a penile fracture, scarring from surgery or injections, and constriction from a ring or band.

What is an hourglass deformity of the penis?

An hourglass deformity is a band of narrowing around the erect penis, making it wider above and below the narrow section. It is usually caused by a ring-shaped Peyronie's plaque. It may cause instability or bending at the narrow point.

Can penile narrowing go away by itself?

In early Peyronie's disease, symptoms improve in some men, stay the same in many, and worsen in others. Pain usually settles. A fixed narrowing that has been present for many months rarely goes away by itself, but treatment can improve it.

Is penile narrowing a sign of cancer?

Penile narrowing is very rarely caused by cancer. Penile cancer usually causes a sore, growth or skin change on the head of the penis or foreskin rather than narrowing of the shaft. A hard lump should still be checked by a doctor.

Can Peyronie's disease cause erectile dysfunction?

Yes. Many men with Peyronie's disease also have erectile dysfunction. The scar can affect blood flow and the firmness of the erection beyond a narrowing. Erectile dysfunction treatment often helps, and severe cases may benefit from a penile implant.