Peyronie’s disease (PD) is a connective tissue disorder characterized by the development of fibrous scar tissue, known as plaque, within the penis. This plaque forms in the tough, elastic sheath surrounding the erectile chambers, which is called the tunica albuginea. The most frequent concern for men diagnosed with PD is the effect the condition has on the size and shape of the penis, specifically regarding measurable length and girth.
The Role of Plaque Formation in Structural Change
Peyronie’s disease is considered a wound-healing disorder, often following microtrauma to the erect penis. During the healing process, a dysregulated immune response leads to the overproduction of collagen, forming a dense, non-elastic scar tissue known as a plaque. This plaque localizes within the tunica albuginea, the primary layer responsible for maintaining rigidity and shape during an erection. Normal tunica albuginea is composed of elastic fibers that stretch to accommodate blood flow.
The fibrous plaque is rigid and inelastic, preventing the affected area of the tunica albuginea from stretching like the rest of the tissue. When the erectile chambers fill with blood, the unaffected side lengthens and expands normally, while the scarred side cannot. This mechanical restriction creates a hinge effect, leading to localized shortening and a characteristic bend.
During an erection, the tunica albuginea must reach its maximum length and width to achieve full rigidity. The presence of the rigid plaque obstructs this normal expansion and stretching, which can lead to localized indentations or narrowing, sometimes described as an “hourglass” deformity. This inelastic tissue can also compromise the integrity of the underlying erectile tissue, contributing to impaired blood flow and reduced rigidity.
Documenting and Quantifying Length Reduction
Penile shortening is a recognized consequence of Peyronie’s disease and a common concern for patients. The loss of length and girth is caused by the plaque’s contraction and the resulting structural deformity. Measurement of this size loss often involves comparing a stretched flaccid measurement taken before disease onset to a measurement taken after the plaque has stabilized.
Clinical studies have documented measurable reductions in length, though the degree of loss is highly variable among individuals. Patients with more severe cases of PD may experience a loss of one to three centimeters. The perceived loss of length can be greater than the actual tissue shrinkage due to the visual effect of the penile curvature, which makes the functional straight length appear shorter during attempted penetration.
Quantifying the true extent of length and curvature requires objective measurements, typically performed in a clinical setting using an induced artificial erection. Methods like intracavernosal injection (ICI) of vasoactive agents are considered the gold standard for accurately determining the degree of deformity and the straight, erect length. Studies tracking the natural history of the disease show that measurable shortening can occur in a significant portion of patients, even after the plaque has stabilized.
Other Manifestations of Peyronie’s Disease
While size reduction is a primary concern, Peyronie’s disease presents with other significant physical manifestations that affect function and appearance. The most widely recognized symptom is the formation of a distinct penile curvature or bend, which occurs because the inelastic plaque restricts expansion on one side of the shaft. This bending can be upward, downward, or sideways, depending on the plaque’s location in the tunica albuginea. If the bend exceeds about 30 degrees, it can make sexual intercourse difficult or impossible.
During the early, or acute, phase of the disease, many men experience pain with erection, which is a symptom of the ongoing inflammatory process. This pain usually lessens or resolves as the condition enters the chronic phase and the plaque stabilizes. In addition to the bend, the plaque itself is often palpable beneath the skin as a flat lump or band of hard tissue.
The physical changes caused by the plaque can also lead to erectile dysfunction (ED) in a substantial number of men with PD. This ED can result from anatomical changes, such as the plaque invading the underlying erectile tissue, or because the severe curvature causes the penis to buckle. The deformity can also impair the mechanisms that trap blood in the erectile chambers, leading to softer erections.
Interventions Targeting Tissue Remodeling
Managing Peyronie’s disease often involves interventions aimed at minimizing or reversing the structural changes caused by the fibrotic plaque. Non-surgical approaches are frequently utilized, especially in the acute phase, to limit the progression of deformity and subsequent size loss. Penile traction therapy, which involves wearing a device that applies tension to the flaccid penis, is one such method. This mechanical force is designed to encourage tissue remodeling and is the only non-surgical treatment reliably shown to increase penile length in some patients.
Injectable medications are another strategy used to target the plaque directly. Clostridium histolyticum collagenase, approved by the Food and Drug Administration (FDA), is injected into the plaque to break down the excess collagen that forms the scar tissue. Other agents, such as verapamil or interferon, have also been used to disrupt the scar tissue and prevent further fibrosis. Early intervention during the acute phase is emphasized, as it provides the best opportunity to mitigate structural damage and limit the eventual loss of length and girth.