This is the fourth part of a series of posts on comparing Welch Allyn products that will help incoming first year medical students learn about and select different medical instrument components to construct the right Welch Allyn diagnostic kit (otoscope and ophthalmoscope). The focus of this discussion is on Welch Allyn diagnostic kit otoscope heads.
Unlike prior posts in this series that assist medical students in deciding on which type of products to purchase, this one will focus more on the variability normally encountered by medical students when they first hit the clinic. Most retailers offer only one option for otoscopes in their diagnostic kit even though Welch Allyn manufactures two varieties, so purchasing decisions are not really an issue. However med students still need to know how to use all the historically popular versions and accessories, and what to avoid if buying an older model. As with ophthalmoscope heads, all of the below otoscopes are the 3.5 volt version, which refers to the standard power handles, and are in contrast to miniature “pocket sized” versions of these instruments.
First, let’s review the older pneumatic otoscopes, seen right. The thing to take away from the discussion of this type of scope is that you should not buy one. The general concept is the same as all the other otoscopes, without the shiny distracting bells and whistles you’ll never use. However the big difference between this and the next Welch Allyn otoscope type is the tip. Notice how the base of the tip is rather wide? It is essentially the diameter of the barrel of the scope itself. There is no inherent problem with such tips, as they work perfectly well if you can actually find them, but the chances of coming across one in hospitals and clinics is rather low unless that clinic is specifically using this type of otoscope. So, if you happen to come across one in clinic, you now know to shove the wide-base tip into the wide barrel of the otoscope. However you are also aware that buying one of these most likely comes with providing your own lifetime supply of tips.
Next, let’s look at one of the latest Welch Allyn models to become obsolete for absolutely no reason: the standard diagnostic otoscope. This is the model you are most likely to come across in clinics and hospitals, because they are generally a solid and reliable means of assessing ears. You will also come across other otoscope makers that produce similar looking scopes (to be reviewed in future posts). If you do want to save money by buying an older used diagnostic kit, this is the otoscope head to get.
Unlike the previous otoscope, this model and the following one both use standard otoscope tips, but through different means. The covered end of the scope (under the black plastic tip) is conical metal, and has a groove cut into the top of it that helps lock in a bump of plastic on the inside of the tip. The common mistake med students make is just shoving the tip on without lining up bump with groove, which means the tip doesn’t actually make a secure connection with the otoscope and readily falls off during the examination. While it is especially hilarious to observe medical students accidentally detach the tip and find it dangling out of the patient’s ear (sometimes without their knowledge), this is generally a newbie move to avoid. You should be able to give a slight tug on the tip to ensure it is secure.
The other difference to note between this and its predecessor is the input for the insufflator bulb, which is an accessory used to push air into the ear and gauge movement of the tympanic membrane. You may never use an insufflator bulb throughout med school, and should not buy one. Pediatric offices that require their use will supply them. Nonetheless, Welch Allyn decided to change up the industry standard of having a tube attach onto an external plug (female port) to an extra piece of plastic that gets plugged into a hole in the side of the scope (male port). You can see the additional end piece in the image on the right. I’m sure they saw a minor rise in sales because of that change, but medical students should not purchase this accessory.
Lastly, we come to the unnecessary but unavoidable up-sell, the Welch Allyn Macroview Otoscope. Despite decades of doctors being able to visualize the ear canal perfectly well with standard otoscopes, Welch Allyn claims “this instrument is a significant advance in hand-held otoscopy…”
Their key selling points are that this otoscope doubles the field of view and increases magnification by 30% compared to other models. The former may be helpful, but otherwise you can simply move the scope if you want to view the tympanic membrane periphery. That’s how doctors have done it for decades. The increased magnification simply isn’t noticeable. Remember back when you last used a microscope? The lowest setting was the 10X lens, followed by the 40X lens. That’s 400% greater magnification. This offers a 30% increase, which would be like moving up to a 13X lens on your microscope. In the world of light otoscopy, it sounds like a big improvement, but this really isn’t doing much. This also comes with “the ability to adjust focus for variable ear canal length or farsighted eyes,” which is yet another issue doctors have never really had a big problem with historically.
The macroview otoscope also uses standard tips, but instead of holding onto them by a groove internal to the tip, they actually secure the tip externally. Ridges found near the tip base actually twist under the end of the otoscope head. This is actually a nice improvement, as it does a better job of securing the tips. Of note, you most likely should not need to purchase otoscope tips yourself, as clinics provide them. Be sure to always grab 10 or so extra for your case, just in case you run into a clinic which is not so courteous.
Another key difference in the Welch Allyn Macroview Otoscope is that its lens cannot be rotated or slid aside for direct access to the ear with a curette through the barrel of the otoscope. This is often used to remove ear wax under direct visualization. However, most attendings will not want medical students to be performing manual cerumen disimpaction, as there have been rare case reports of bones in the ear accidentally being removed during this process. Remember: never manually disimpact unless you can directly visualize some portion of the tympanic membrane!
Despite this article poking holes in the advertising of Welch Allyn, this is overall a great otoscope to have. It is reliable, sturdy, and a great tool to visualize the ear canal, which are all excellent qualities as it is most likely your only diagnostic kit option. Unlike differing ophthalmoscope designs that require different learning and skill sets to actually use, there is no difference in the physical use of any of the above otoscopes. That essentially means you can purchase and learn on the Welch Allyn Macroview Otoscope, and still know how to use any standard wall-mounted otoscope in an office or emergency department setting.
In summary, the direct comparison is as follows:
in New Kit
||$150||Large Base||yes||special order only|
|* prices are for the otoscope heads only. handles are sold separately.|
Prices are higher if you purchase components separately, so try to buy a value meal (a complete diagnostic kit sold as a single unit) unless you can find a really great deal. With that being said, the above three scopes were added to the price-check plugin as a reference.