Description

The 90D Lens is an essential tool for ophthalmic professionals, designed to enhance the capabilities of slit lamp biomicroscopy. This non-contact diagnostic lens is renowned for its ability to provide detailed examinations of the retina, including both the posterior pole and peripheral regions. Its effectiveness extends to use with small or undilated pupils, making it a versatile choice for comprehensive retinal assessments.

Key Features

• Double Aspheric Glass Optics: This design minimizes peripheral image distortion and enhances depth of field, ensuring high-definition imaging with exceptional clarity.
• Non-Contact Design: Allows for safe and hygienic use without direct contact with the eye.
• Small Diameter Ring: Facilitates easy manipulation and dynamic examination within the orbit.
• Multi-Layer Anti-Reflection Coating: Available on some models to optimize light transmission, further enhancing image quality.

Construction and Durability

The lens features a durable construction with a scratch- and mildew-resistant anodized metallic ring, providing a secure grip. Available in multiple colors, including Black, Blue, Gold, Green, Purple, Red, Silver, and Champagne Gold, it offers both functionality and aesthetic appeal.

Technical Specifications

• Image Magnification: Approximately 0.76x to 0.75x, depending on the manufacturer.
• Laser Spot Magnification: Ranges from 1.32x to 1.34x.
• Field of View: Static angles range from 74° to 94°, with dynamic angles reaching up to 153°.
• Working Distance: 7 mm, with a lens diameter of 22 mm.

Optical Properties

The 90D Lens forms an inverted image of the retina, with magnification influenced by axial ametropia and lens-to-eye distance. This requires a correction factor for accurate optic disc size estimation, providing precise diagnostic capabilities.

Use Cases

Ideal for general ophthalmic diagnosis and treatment, the lens supports detailed examination of the optic disc, macula, retinal arcades, nasal retina, and posterior vitreous. It is particularly suitable for diabetic fundus evaluation and for patients who prefer not to have their pupils dilated. Additionally, it serves as a valuable training tool for students and residents learning slit lamp fundus examination.

Maintenance and Cleaning

Proper care involves cleaning with isopropyl alcohol or mild detergents, and disinfecting with approved solutions. Sterilization can be achieved using ethylene oxide or steam methods, while avoiding autoclaving, boiling, or solvent soaking. Regular inspection for damage and appropriate storage in the provided case are recommended to maintain lens integrity.

Widely recognized as the gold standard for slit lamp fundus examination, the 90D Lens is often recommended as a primary workhorse lens for ophthalmologists, with no known contraindications. Its reliable performance and robust design make it an indispensable asset in the field of ophthalmology.