Often it is necessary and helpful to have portable devices. They are useful when one travels to see patients where there may not be a complete clinic set up, when seeing patients bedside at the hospital, or when examining a pediatric patient who is difficult to position behind the mounted slit lamp.
Below is a discussion of various portable slit lamps and indirect ophthalmoscopes you can carry with you wherever you go.
Portable Slit Lamps
Haag Streit
BA904-A Portable Slit Lamp with Chinrest
BA904-C Portable Slit Lamp without Chinrest
These portable slit lamps can be adjusted to 0.12 mm, 0.25 mm or 0.5 mm slit widths, 3 mm, 5 mm, 8 mm and 14 mm slit heights and comes with blue and yellow color filters. The BA904 has a dioptic range of -8 to +8 and an interpupillary range of 53 to 95. The rechargeable NICAD battery allows up to 45 minutes of continuous use. This slit lamp filters out hazardous radiation, minimizing damage to the lens and retina when using magnifying lenses.
The BA904 portable slit lamps can be mounted onto a chinrest or can be used without. Both versions come with accessories that can be purchased separately, such as cases, rechargeable energy packs and power supplies.
Reichert
PSL Portable Slit Lamp
This portable slit lamp uses white LED technology, giving approximately 10,000 lux and having a lifespan of 50,000 hours. The lamp weighs about 1.5 lbs including the battery so it can easily be used at the bedside. The battery can power the unit for up to 2 hours.
Kowa
SL-15
This portable slit lamp is 8.7” W x 4.2” D x 8.4” H and weighs approximately 28 ounces. It has a sculpted grip for a trigger style light switch. The light source is 15-watt halogen with a built in cobalt blue filter. Magnifications of 10x and 16x are available as well as a slit width of 0.1 mm, 0.2 mm, 0.8 mm or 12 mm spot. This slit lamp also supports digital video with the optional C-mount adapter. Other available options include a headrest, carrying trunk case and extra lithium-ion battery.
Keeler Ophthalmic Instruments
PSL One Portable Slit Lamp
PSL Classic Portable Slit Lamp
Keeler makes portable slit lamps that operate at 10x and 16x magnification and have controllable illumination from maximum to zero. These slit lamps have fixation targets and a 1 mm square light patch for assessing a/c flare. Both of these portable slit lamps come with an iPhone 4 adapter, available for approximately $200. The PSL carrying case is an additional $203 and replacement bulb is $60.
Heine
Heine HSL 150 Hand-held Slit Lamp
This slit lamp adjusts from 0.2 mm x 10 mm to 4 mm x 14 mm slit size. The magnified view with a 20-diopter loupe allows for 6x magnification. It also has a blue interference filter for corneal examinations. It runs on a 2.5V or 3.5V XHL Xenon Halogen Technology. The weight of the head is 70 g and attaches to the Heine Beta Slim handle seen above.
Heine HSL 10x Loupe Attachment
You can get 10x magnification when this loupe is attached to the HSL 150 Loupe, increasing the working distance between the examiner and the patient. There is also a detachable TP-elastomer eyepiece to steady the instrument on the brow and avoid stray light.
Portable Indirect Ophthalmoscopes
Heine
Heine offers a variety of hand-held indirect ophthalmoscopes, which are listed below.
Hand-held indirect ophthalmoscope, monocular
This ophthalmoscope has a built-in interference red-free filter to improve contrast. It has a metal construction and all optical components are made of coated optical glass. There is an adjustable light beam, which is useful for small pupils. This instrument can be used with one hand and has a +3D lens and binocular attachment available. (see picture at right).
The addition of this binocular attachment makes stereoscopic examination possible. Symmetric PD selection is from 54 mm to 74 mm. This unit can be used with either a 3.5V rechargeable handle or a 6V cord handle with desk transformer.
Heine Sigma 150 Binocular Indirect Ophthalmoscope
This indirect ophthalmoscope can be mounted onto spectacles or a headband and can be adjusted for pupillary distances between 48 to 74 mm. It is a lightweight unit (90 g). If a prescription lens is desired, it can be easily clipped into the frame. Two separate controls let you select the ideal setting for parallax and convergence. The illumination beam can be adjusted by +/- 3 degrees to eliminate reflexes. This unit operates with a 6V/5W XHL xenon halogen bulb and has an integrated red-free filter to improve contrast. There are also detachable blue and yellow filters for fluorescence angioscopy.
Heine Omega 500 Binocular Indirect Ophthalmoscope
This indirect ophthalmoscope comes with LED or XHL xenon-halogen lamp illumination that is multi-coated. It has a synchronized adjustment of convergence and parallax for stereoscopic fundus images through any pupil size, down to 1 mm. This scope is dust-proof, apertures and filters can be locked into a desired position and the adjustment levers have a ‘friction-clutch’ to protect from forced adjustment while in the locked position. The pupillary distance can be adjusted between 46 and 74 mm.
The LED HQ system provides for 100% more light, longer operation times and consistent light output up to 20,000 hours. The XHL Xenon Halogen OMEGA 500 can be upgraded to the LED HQ easily. The HC50 L Headband Rheostat controls the LED and XHL xenon halogen illuminations.
Heine OMEGA 500 Headband
This HC 50 L Headband Rheostat can be mounted on the left or right sides of the headband. There is an articulating hinge that provides vertical adjustment of the rear band of the headband for individual placement. The ergonomic design transfers the weight across the surface of the entire headband so there are no pressure points. The cables are integrated in the overband to eliminate a cable loop from instrument to headband. There is a flip up adjustment to raise the optics out of the line of sight. The optics can be flipped and locked at 0, 12.5, 47.5 or 60 degrees.
Heine OMEGA 200 Ophthalmoscope
This indirect ophthalmoscope is headband-mounted and has teaching mirrors on both sides to allow 2 observers to see identical images. This unit has synchronized adjustment of illumination and observation beams, allowing stereoscopic examination through pupils down to 1.2 mm in diameter. The illumination beam can be fine-tuned +/- 4 degrees, which allows for difficult examinations in the periphery. The optics swing into the stand-by position and, when released, return to the exact same position as before.
Both the OMEGA 500 and 200 can be operated with the mPack seen at right, making these indirect ophthalmoscopes truly portable.
Heine OMEGA 500 Unplugged
This unit has a headband battery pack, eliminating cable connections and increasing freedom of movement. The battery is rechargeable and is lightweight. Operating time is 2 hours with the standard 6V, 5W lamp.
Accessories available for the Heine products include trainer scopes, lenses, scleral depressors, extension cords and cases.
Keeler Ophthalmic Instruments
All Pupil II LED Slimline Wireless
This ophthalmoscope can be adjusted for pupillary distances between 47 and 75 mm. This unit has 2000 lux of light, which can be turned down to 2% of the total illumination when necessary. It weighs just 520 g and is operated by a small wireless battery. The unit comes with 2 lithium polymer batteries. There is a single control to change aperture size and position in one movement. There is also a built in full time IR and UV barrier to improve patient safety.
Spectra Iris
This indirect ophthalmoscope is compact and has a newly designed adjustable aperture slider for pupil sizes from 20 to 60 mm. It can be adjusted for pupillary distances between 48 and 76 mm. The illumination is by LED, lasting up to 4 hours. The Spectra Iris comes on the Keeler Sport wrap around frame. The optical box and light pod can be flipped up.
Vantage Plus
This headband-mounted unit offers a choice between a neutral 4000K LED for longer life, better contrast and whiter light, or a 3800K traditional bulb. When you change the aperture on this unit, the optics and mirrors automatically adjust for stereoscopic views through all pupil sizes. The pupillary distance can be adjusted between 48 and 76 mm. This unit can be used with or without wires.
Welch Allyn
Binocular Indirect Ophthalmoscope
This ophthalmoscope adjusts to fit interpupillary distances of 49 to 74 mm. The SoftTilt park/rest feature allows the optics to be moved out of the line of vision. This unit operates with a halogen light source and has a diffuser filter that broadens the illumination beam to make viewing the peripheral retina easier. A portable power source or wall/desk power source is available.
Above is a discussion of some of the available portable devices. Most companies make versions of instruments that can be taken with you on the road.
Portability is a nice feature to have when in a busy practice. Not only does it allow you to travel with your office, but also even in your office, these devices allow you to move from room to room between patients in a busy practice with the need for only one unit, thereby cutting costs.