Spider veins are dilated venules, not distended capillaries and for sure not “varicose veins” as considered by some in purpose to mislead naive readers but mainly insurance carriers…
Capillaries (Latin “capillaris” meaning: “of/or resembling hair”) are the smallest of body’s blood vessels having an inner diameter of only 5-10 µn or microns (a micron is a thousand’s of a millimeter or 0.001mm). Spider veins measuring between 0.1-1mm have a much larger internal diameter therefore they are venules and not distended capillaries.
Spider veins (from the resemblance to a spider’s web) are also called telangiectasia (Greek for “distended distal (“far”) blood vessel”) are usually localized mainly on the legs and face but can be occasionally seen on the neck and chest as well. There is a recognized familiar tendency and women are mostly affected thus female hormones and of course pregnancies are incriminated in their formation. Certainly, there are many other reasons among which increase in venous pressure in the legs as frequently seen in patients with varicose veins or mainly deep vein problems when they are specifically localized at the ankle area and called "ankle flare". Occasionally, local trauma can induce spider veins as well. If present on the neck and upper chest they could be the result of excessive sun exposure.
Spider veins represent basically just a cosmetic nuisance. Indeed, localized barely beneath the surface of the skin they are visible due to the relative abundant blood flowing through them. Being multiple and minute in size removing them by surgery is not an option; closing them to prevent blood flow is the only practical therapeutic goal. This is achieved by injection sclerotherapy or by heat destruction/desiccation by lasers.
I would classify spider veins in two major types: the smallest in diameter the red ones and the more larger, the darker blue ones. The “larger” i.e. darker the vein the sclerotherapic response will be better. Usually several injection sessions are needed however, in avarege 2-4. Excessive treatment is to be avoided as it can induce creation of even smaller so called second generation spider veins or matting which are difficult, sometimes almost impossible to treat.
By the way, there is no cure for the condition and 70-80% improvement is considered a good result. However, the rule of the thumb is their tendency to reoccur with passage of time, same or different places.
Lasers have been introduced with much fanfare in the mid/late nineties. The word LASER stands for Light Amplification by Stimulated Emission of Radiation. Applied through the skin the therapeutic principle is that the energized/stimulated monochromatic light beam’s generated high temperature should literally “evaporate” the small veins. Unfortunately, and simply put, on leg’s spider veins lasers just do not work and sometimes the condition is made worse as depicted in two pictured cases . This is not just my personal experience but experiences of many moral and ethical practitioners I came in contact during the years who like myself will never offer this therapeutic modality for leg's spider veins. I know dozens of dissatisfied patients who felt cheated after spending large sums of money for a procedure that failed them. The only place I have seen much improvement is on small spider veins of the face.
The known complications are skin burn if the power and length of time was excessive. One should be also careful getting sunburned after treatment. In conclusion, the only effective therapeutic modality for leg's spider veins remains injection sclerotherapy.
Sclerotherapy involves injecting directly into the vein different substances that will cause a chemical injury of the inner lining of the vein. Like any other type of body injury, this chemical injury will end up healing and the (non visible) scar tissue formed will close and shrink the vein(s). As blood will not be able to flow through the injected vein, the net result being that the unwanted vein will not be visible anymore or at least will much fade. Of course this imply a good therapeutic response from the treated patient. Indeed, the practitioner has to master a good injection technique, has to know what to inject, what volume, and what concentration to use. The actual spider vein closure is done by the patient’s response to this therapeutic challenge.
The word Sclerotherapy implies closing of an unwanted vein by the formed scar tissue. It is known that scar tissue is a hard tissue and since hard in Greek is sclera; sclerotherapy is basically “treatment/therapy by hardening”.
Several sclerosing agents are available today: Sodium tetradecyl sulfate (Sotradecol or STD) and Ethoxysclerol/Polidocanol / Sclerovein / or Asclera in the US being the two most frequently used. STD is an American solution introduced in 1946. Asclera was used in Europe since 1968!! yet the FDA only approved it –finally- in 2010! Sotradecol is probably a more stronger sclerosant, however, for spider veins both solutions can be used in appropriate concentration.
Please note, that the delivery of the two above-mentioned solutions can be in the original liquid form as it was done for decades or in a more recent foam/froth form i.e. solution mixed with air. As injecting air directly into the circulation can have unpleasant even dangerous side effects (confusional states, limb paralysis, transient blindness) the volume injected per session has to be much limited increasing possibly the number of needed sessions.
Saline solution (hypertonic saline or basically concentrated table salt) is used by mainly dermatologists. We prefer not to use it as it is painful when injected; it is also a strong solution with higher potential for local complications such as brown pigmentation and skin ulceration that will end in a lifetime scar.
Several setups are also using compression after sessions mainly in a form of an elastic stocking. It is not a mistake, however, personally I use it rarely as the experience teaches it is not needed in well above 95% of cases.
Brown pigmentation/freckling and even tissue damage in form of small skin ulceration (see picture attached) will happen if the solution concentration was to high relative to the vein size. The ulceration will certainly heal ending in a small scar, similar to scars left behind chicken pox. In case of a much larger vein (several mm in diameter) compression may be need to prevent clot formation and subsequent brown pigmentation or freckling of the skin. Occasionally, post injection, a larger vein gets inflamed, (not infected) around the clot causing local pain, swelling and redness, a typical case of superficial phlebitis. Treatment in these cases will be evacuation of the clot local compression and NSAID drugs like Advil/Motrin, Aleve etc. for several days. Antibiotics are never necessary!! If you are on birth control pill or hormonal treatment the incidence of this complication is increased.Occasional ankle swelling is possible especially if the treated area is close to the ankle. Bruising is almost visible at the beginning of the treatment in most cases especially if you bruise easily and most women do. It will fade without any treatment in 10-14 days. Raised reddish skin (welts) and itching (similar to a flee or mosquito bite) after the sessions is a frequent occurrence and it is caused by the liberated histamine in the skin.
People very sensitive to the pain caused by multiple injections should be offered a topical anesthetic available in creams (Emla, Lidocaine) or skin patches (Lidoderm).
Systemic complications such as allergic reactions have been only rarely reported in the literature. Since 1984 and thousand of patients treated I have not encountered one such reactions. I have seen several patients without history of migraines developing at the end of the session (and after resuming the upright position) unpleasant visual field defects. Usually after 10-20 minutes of rest in the office the patients were able to leave the office and drive away. Such occurrences basically represent a migraine equivalent and the release of histamine with other vasoactive substances probably play a role in inducing them.