"Which dermatoscope is best for diagnosing melanoma?"

Not too infrequently, customers will directly ask, “which dermatoscope is best for diagnosing melanoma?”

Those of you who are truly into dermoscopy understand that there's no single answer to that question. Dermatoscopes do vary in their features, but most would agree that 𝗶𝘁'𝘀 𝗮𝗰𝘁𝘂𝗮𝗹𝗹𝘆 𝘁𝗵𝗲 𝗱𝗲𝗿𝗺𝗼𝘀𝗰𝗼𝗽𝗶𝘀𝘁 (𝗮𝗻𝗱 𝘁𝗵𝗲𝗶𝗿 𝘀𝗸𝗶𝗹𝗹 𝗹𝗲𝘃𝗲𝗹) 𝘄𝗵𝗶𝗰𝗵 𝗺𝗮𝗸𝗲𝘀 𝘁𝗵𝗲 𝗴𝗿𝗲𝗮𝘁𝗲𝘀𝘁 𝗱𝗶𝗳𝗳𝗲𝗿𝗲𝗻𝗰𝗲.

That being said, there are some general "rules of thumb" that those who are new to dermoscopy should consider:

𝗟𝗮𝗿𝗴𝗲𝗿-𝗹𝗲𝗻𝘀𝗲𝗱 𝗱𝗲𝗿𝗺𝗮𝘁𝗼𝘀𝗰𝗼𝗽𝗲𝘀 𝗮𝗿𝗲 𝗺𝗼𝗿𝗲 𝗹𝗶𝗸𝗲𝗹𝘆 𝘁𝗼 𝗶𝗻𝗰𝗹𝘂𝗱𝗲 𝘁𝗵𝗲 𝗲𝗻𝘁𝗶𝗿𝗲 𝗹𝗲𝘀𝗶𝗼𝗻 𝘄𝗶𝘁𝗵𝗶𝗻 𝘁𝗵𝗲 𝗳𝗶𝗲𝗹𝗱 𝗼𝗳 𝘃𝗶𝗲𝘄 (𝗙𝗢𝗩). Some dermatoscopes, like the DL100, Carbon, and DL1 have lenses which are relatively small at only 15mm in diameter. 

Most "serious" dermoscopists tend to buy dermatoscopes which have lenses that are twice as large (or more). For example, the DL5's lens measures 32mm in diameter, the DL4's lens measures 30mm, and the DL200 line measures 25mm.

When you're dealing with a large lesion that doesn't "fit" within the FOV, one could argue that not seeing the entire lesion at once could potentially increase the likelihood of something being missed. But this is just speculation, as there's really no evidence that smaller lenses result in increased errors. 

One thing is for sure though, which is that larger lenses are more convenient and comfortable to use - no shifting, moving around, scanning in "sections" is needed.

𝗠𝗮𝗴𝗻𝗶𝗳𝗶𝗰𝗮𝘁𝗶𝗼𝗻 𝗼𝗳 𝟭𝟬𝘅 𝗶𝘀 𝗰𝗼𝗻𝘀𝗶𝗱𝗲𝗿𝗲𝗱 𝘁𝗵𝗲 "𝘀𝘁𝗮𝗻𝗱𝗮𝗿𝗱" 𝗳𝗼𝗿 𝗽𝗶𝗴𝗺𝗲𝗻𝘁𝗲𝗱 𝗹𝗲𝘀𝗶𝗼𝗻 𝗲𝘃𝗮𝗹𝘂𝗮𝘁𝗶𝗼𝗻.

Nearly all dermatoscopes we offer provide 10x magnification, but some don't. 

For example, the Lumio S is 4x. The Dermlite GL has two lenses, the strongest of which is 6x. 

All magnification levels will enhance your diagnostic accuracy, but in order to see some of the very subtle details, colors and structures that are most associated with melanoma, 10x is ideal.

https://pubmed.ncbi.nlm.nih.gov/24002051/

https://pubmed.ncbi.nlm.nih.gov/29138058/

The largest lens and highest magnification won't make a difference if the dermatoscope itself isn't being used. 

This is one of the reasons why, for some docs, owning two dermatoscopes would actually be the ideal setup. 

For those who don't carry their dermatoscope with them into every examination, the question is, "why?'

For those who don't like to squint, a larger-lensed dermatoscope like the Lumio S would be a great "carry around" dermatoscope. Its magnification limits could be offset by also owning a 10x dermatoscope which could be used "here and there" when particularly suspicious lesions need a closer examination.

The verdict is that there is no single best dermatoscope for diagnosing melanoma.

If regardless of the size, weight, or shape of a dermatoscope, you know that you'll use it consistently during all skin exams, then go for the largest-lensed, 10x Dermlite dermatoscope you can afford.

However, if other factors play an important role in your comfort (and willingness to use the dermatoscope regularly), there's nothing wrong with admitting that! Just be honest with yourself, and purchase whichever dermatoscope is light enough, large enough, or small enough that it motivates you to carry and use it regularly during all skin exams.