Grenz zone

Absent Grenz zone, loss of elastic fibers, elastogenesis, decreased thickness, microvasculature normal, no evidence of inflammation... 

Grenz zone prominent, elastogenesis, elastosis, collagen degeneration, loss of anchoring fibrils... 

This paragraph particularly concerns superficial peels or peels to the Grenz zone . Papillary dermal peels are not really indicated in cases of active acne. 

Results of the treatment of hyperpigmentation disorders depend entirely on the depth of the problem and the depth of the treatment. They are frequently treated with peels that reach or go beyond the Grenz zone, in conjunction with appropriate daily care. The only way to treat melasma permanently is by completely destroying the cells that produce melanin, by peeling beneath the... 

Solar or senile lentigines respond partially to peels to the Grenz zone and the papillary dermis. They sometimes require a peel to the reticular dermis to get rid of them completely. This deep peeling can be local. 

The basic protocol for ETCA is intended to reach the basal layer of the epidermis or the Grenz zone. There are (many) other deeper protocols but they are not as straightforward as ETCA and the risk of complications is relatively much higher. ETCA is not necessarily a light peel it can be used to reach all depths, from the basal layer of the epidermis to the reticular dermis, depending on the protocol used. The relatively superficial action of the ETCA solution (basic protocol) strongly stimulates the skin regeneration... 

It takes 10 minutes to apply ETCA to the basal layer or the Grenz zone, from the time patients lie down to when they get up. 

See Chapter 34 for application of the Lip Eyelid formula. Although it must be taken into account that four peels to the Grenz zone are not necessarily as efficient as one peel to the papillary dermis. The latter can destroy a large number of lesions that peels to the Grenz zone do not always reach. Some studies suggest that DMAE can eliminate the lipo-fuchsin in lentigines. 

Grenz zone Destruction of the Grenz zone Medium duration... 

On the other hand, when the desired effect is destruction of deeper layers of the dermis and epidermis to eliminate certain lesions, a single deeper peel may be a better indication than repeating several peels to the Grenz zone, as is the case when treating lentigines and mixed or dermal melasma. 

Lentiginosis and photoaging, (a) Before treatment, there are about 40 lentigines and/or actinic keratoses, (b) After four sessions of Easy TCA peels to the Grenz zone, there are only about 10 lentigines/keratoses left. The signs of photoaging are visibly reduced fine lines, quality of the skin, improved eyelid tension, etc. 

A peel to the basal layer lightens the freckles, sometimes only temporarily. A peel to the Grenz zone removes many freckles and lightens others. A peel to the papillary or reticular dermis gets rid of freckles altogether (Figure 13.11). 

Here too a combination of techniques proves worthwhile. Acne responds well to a TCA peel to the basal layer or the Grenz zone, whether it is comedonal, microcystic (Figure 13.16), papular or papulopustular. Deeper peels, to the papillary dermis, should not be used when acne is still active, because of the increased risk of infection (see Chapter 37). The number of open or closed comedones can be expected to decrease after several TCA peels. We shall see how the Easy TCA technique allows comedones and microcysts to be opened immediately before the peel, which gives faster and better results. Seborrhea is often reduced after TCA... 

Insulin-dependent diabetes depending on the depth of the peel and the risk of infection. Type 2 diabetes is not a contraindication for peels. Patients with stable insulin-dependent diabetes can be given a peel to the Grenz zone... 

Local anesthetic is never needed when TCA is used to treat the epidermis to the Grenz zone. It may be necessary when the TGA reaches the papillary or reticular dermis. 

Cloudy-white frosting the peel has reached the Grenz zone (Figure 14.3) Flaking light, thin skin (Figure 14.4)... 

Basic protocol removal of the Grenz zone. The peel reaches the Grenz zone Cloudy-white frosting 4 peels 1 per week... 

After pure white frosting has appeared on the lesions, ETCA is applied to the rest of the face following the basic protocol. The protocol to the Grenz zone reduces the number of small superficial AKs or SLs, as well as lesions that are too small to be seen by the naked eye. 

The fibroblasts in the papillary dermis are stimulated and proliferate they synthesize a large quantity of new collagen, which is deposited in bands beneath the epidermis (in the Grenz zone). The intercellular matrix is enriched in gly-cosaminoglycans. Further down, short-lived but rapid vasodilation occurs, that signaling the presence of dermal inflammation. 

Litton proposed using a detergent other than septisol and recommended using glycerol. He was one of the first to describe an increase in the thickness of the Grenz zone after a phenol peel. 

Keratinocytes Epidermal basal layer Grenz zone Papillary dermis Reticular dermis Elypodermis... 

On contact with the papillary dermis, phenol destroys the entire elastotic layer within it. Thereafter, the architecture of the dermis is spectacularly restored. Immediately underneath the basal membrane, in the Grenz zone, a dense new layer of collagen fibers is formed, arranged parallel to the... 

The patient in Figure 29.9 is a typical case where the facial photoaging would benefit far more from a full-face phenol peel than from a neck- and face-lift. Nevertheless, phenol, with difficulty, tightens and rejuvenates the neck, which will only benefit from surgery followed by a peel to the papillary dermis or several peels to the Grenz zone (with ETCA) to improve the quality and the color of the skin after the surgical face-lift. 

Normal face-lift scars are not usually too unsightly, but some patients want a treatment to soften them or get rid of them completely. A full-face phenol peel is the best option (Figure 30.19), but a local application of phenol precisely on the scar is also a possibility, in combination with another more superficial peel (to the papillary dermis, the Grenz zone or the basal layer). Standard scars from an upper blepharoplasty do not seem to respond as well to a... 

After an intraepidermal peel, to the basal layer or the Grenz zone, the skin regenerates from leftover islets of ker-atinocytes. In the case of a deep peel, the skin regenerates from its appendages. The face has more pilosebaceous units than the neck, and facial skin regenerates more quickly, with less risk of scarring. 

An evening-out peel is necessary to prevent demarcation lines, it should be applied on the rest of the face when the Lip Eyelid application has finished and before any occlusion is applied. Patients with a light skin type could be given four weekly sessions of Easy TCA (to the Grenz zone) or a single session of Unideep (to the papillary dermis). 

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