ZSI 475 inflatable penile implant.

01 Overview

A three-component hydraulic system that mimics a natural erection.

ZSI 475 is an inflatable penile implant manufactured by Zephyr Surgical Implants, based in Switzerland. It is used in the surgical treatment of erectile dysfunction caused by limited blood flow to the penis or by damaged nerves. Thanks to its three-component hydraulic architecture, the erection is initiated and ended under the patient's control in a way that closely follows the natural physiological cycle.

The two inflatable cylinders are implanted within the corpora cavernosa residing on either side of the penis; no tissue is removed to position them. The saline-filled reservoir is implanted in the pelvis and the manual pump in the scrotum. The patient presses the pump to transfer fluid from the reservoir into the cylinders; pressing the valve at the top of the pump returns the fluid to the reservoir and the penis becomes flaccid again.

The system remains entirely inside the body and is not visible externally. According to the manufacturer's documentation, the device does not affect the patient's capacity to urinate or ejaculate, nor the natural sensitivity of the penis and glans. Lisa Health provides documented supply of the ZSI penile implant portfolio, sizing planning support and operating-room preparation documentation to hospitals and urology teams. Clinical decisions and determination of indication rest solely with the specialist physician.

02 Clinical indications

In which cases is it considered?

The ZSI 475 is positioned for cases of erectile dysfunction that require a mechanical and durable solution. The headings below summarise frequently assessed clinical contexts; final indication, timing and patient suitability are determined solely by the urology/andrology team.

• Vasculogenic erectile dysfunction: cases due to limited blood flow to the penis that do not respond adequately to oral pharmacotherapy or intracavernosal injection.
• Neurogenic erectile dysfunction: ED caused by nerve damage; selected cases after radical prostatectomy, pelvic surgery, spinal pathology or diabetic neuropathy.
• Cases where conservative treatment is insufficient: patients in whom PDE5 inhibitors, a vacuum erection device or injection therapy have failed or cannot be tolerated.
• Peyronie's disease with ED: implantation is considered in selected cases with advanced fibrotic change and accompanying erectile failure.
• Cases prioritising discretion and a flaccid cosmetic appearance: because the device provides a natural flaccid appearance when deflated, a hydraulic system may be preferred over malleable implants.

Contraindications and the assessment of active urinary or systemic infection, uncontrolled diabetes, insufficient tissue perfusion, patient manual dexterity and compliance are addressed within the current instructions for use and clinical protocols.

03 Structure and components

Three components, one closed hydraulic circuit.

The ZSI 475 operates as a closed hydraulic circuit. Fluid is transferred between the reservoir and the cylinders via the pump; the entire system is implanted and requires no external component.

• Inflatable cylinders (2): implanted within the corpora cavernosa on either side of the penis. No tissue is removed during insertion; the cylinders are placed where blood would previously flood to create the erection.
• Manual pump (scrotal): inflates and deflates the cylinders and is implanted in the scrotum. The deflation valve sits at the top of the pump and is suitable for single-handed use.
• Reservoir (pelvic): implanted in the pelvis and filled with saline solution. It stores the fluid volume required to inflate and deflate the cylinders.
• Three-layer cylinder wall: the precise thickness and order of the layers aim to allow good elasticity when inflated, significantly increase resistance to pressure and limit the risk of silicone hernia under strong pressure.
• Hydrophilic PVP coating: applied for better antibiotic absorption and to contribute to protection against infection.
• Tool-free assembly: no additional instrument is needed to join the pump and the cylinder; the connection is designed to be completely sealed.
• Material: all wetted surfaces are manufactured from medical-grade silicone elastomer.

04 Kit and sizing coverage

All standard lengths and instruments in one box.

The ZSI 475 is supplied as a complete kit containing all single-use instruments. Because all standard penile implant lengths and accessories are in the same box, a change of size in the operating room does not require an additional order or waiting time; this structure is designed to reduce stock and logistics burden.

Dimensions and kit contents are compiled from the manufacturer's catalogue; final values are confirmed through the official product documentation and current instructions for use shared with the institution.

05 Operating principle

Hydraulic use in four steps.

Operation is single-handed and requires no external component. Fluid is transferred between the reservoir and the cylinders within the closed circuit.

• 1 — Flaccid state: the cylinders are empty and the penis remains flaccid.
• 2 — Inflation: the scrotal pump is pressed and released repeatedly to transfer fluid from the reservoir into the cylinders.
• 3 — Rigidity: the desired erection is achieved; the cylinders resist a pressure over 500 g.
• 4 — Deflation: pressing and holding the valve at the top of the pump returns the fluid to the reservoir and the penis becomes flaccid.

06 Distinguishing advantages

Highlights for the operating room and patient quality of life.

• One of the stiffest implants on the market: per manufacturer data, the implant composition ensures optimum penile stiffness and the erection resists a pressure over 500 g.
• Designed against silicone hernia: the three-layer cylinder wall is structured to limit the risk of herniation under strong pressure.
• Designed with infection risk in mind: the hydrophilic PVP coating is applied for better antibiotic absorption.
• Logistical convenience: all standard lengths, accessories and single-use instruments in a single box simplify institutional stock management.
• Tool-free, sealed assembly: joining the pump and cylinder requires no additional instrument, aiming to reduce the risk of connection error.
• Tissue-preserving placement: no tissue is removed during cylinder implantation; urination, ejaculation and penile/glans sensitivity are unaffected.
• Cosmetics and discretion: a natural flaccid appearance when deflated, with no visible prominence under clothing.
• Imaging and travel compatibility: not detected by airport security scanners and designed for safe use in medical scanners.
• Warranty: the manufacturer defines a 5-year warranty.

07 Comparison

Choosing between the ZSI 475 and the ZSI 475 FTM.

The two products share the same hydraulic principle but are designed for different anatomies and different indications; they are not interchangeable. The table below compares the two versions for institutional assessment; the clinical preference rests with the specialist physician.

If a non-surgical option for erectile dysfunction is being considered, the Active3 penile vacuum device in the portfolio can be reviewed as a non-invasive alternative.

08 Technical summary

Institutional assessment table.

09 Questions & answers

Frequently asked institutional questions.