Enlarged Pores and Sebaceous Hyperplasia



Enlarged Pores and Sebaceous Hyperplasia


Bradley S. Bloom



ENLARGED PORES


BACKGROUND

Facial pores are a common cosmetic concern across genders and ethnicities. However, there is much confusion both among the lay public and in the medical literature surrounding the definition of “pores” and the etiology of visible pores. The term “skin pores” generally applies to the enlarged openings of pilosebaceous follicular units visible at the skin surface.1,2


PRESENTATION

Skin pores may present as empty funnel-shaped structures or openings filled with cylindrical cornified plugs, which correspond to open comedones1,3 (Figure 9.4.1).
Enlarged pores are most frequently found on the nose and medial cheeks.1






FIGURE 9.4.1 Clinical image of enlarged pores on the forehead and glabella. The pores appear as empty funnel-shaped structures.






FIGURE 9.4.2 Optical coherence tomography of control skin of the lateral cheek (A) compared with the medial cheek (B) with more pronounced pores. (Images courtesy of Bradley S. Bloom, MD.)



PATHOGENESIS

The pathogenesis of enlarged facial pores is poorly understood but is clearly multifactorial, with both intrinsic and extrinsic factors playing important roles. Although there is no consensus agreement, the 3 major pathogenic factors include (1) increased sebum production, (2) increased hair follicle volume, and (3) decreased elasticity surrounding pores.1,2,4,8,9,10 Additional factors that may play a role are genetic predisposition, recurrent acne, seborrhea, sex hormones, chronic ultraviolet light exposure, skin care regimen, topical cosmetics, and vitamin A deficiency.1,3


Sebum Production

A positive correlation of sebum output and pore size has been well described.2 This likely explains the finding that most enlarged pores are found on the nose and medial cheeks where casual sebum levels are higher compared with the lateral cheeks.1 The relationship of pore size and sebum output is particularly well described in men where sebum production is driven by androgens such as testosterone. The relationship of sebum production and pore size is more complex
in women as the sebum production varies with the menstrual cycle. Roh et al. have demonstrated that sebum output and pore size increase during the ovulation phase of the menstrual cycle, which is believed to result from the effects of increased progesterone on sebaceous gland activity.1,2 Although the relationship of sebum output with pore size is clear, there are conflicting data on the relationship of gender and pore size.


Hair Size

It is hypothesized that hair thickness is an important factor in determining pore size. This hypothesis stems from a number of pieces of evidence. First, it has been demonstrated that pore volume correlates with the visual assessment of enlarged pores by fringe projection analysis using 2 and 3-dimensional images.11 Second, pore volume is believed to be composed primarily of the hair follicle with or without the sebaceous gland.1 Third, we know the volume of the dermal papilla correlates with hair follicle diameter and is androgen responsive. Thus, effective treatments for pore size will need to address the hair within the pore.


Loss of Elasticity

Loss of elasticity of the skin is associated with both chronological aging and photoaging.12,13 Several studies have demonstrated a correlation between pore size and loss of elasticity.4,8 It has also been shown that aged and photodamaged skin have decreased expression of microfibril-associated glycoprotein-1 (MAGP-1), which normally stabilizes the microfibril and elastin matrix network of the skin.10 This protein is decreased not only in the dermis but also around pores, and it has been hypothesized that age-related loss of MAGP-1 correlates with enlarged pores.10

Jun 29, 2020 | Posted by in Dermatology | Comments Off on Enlarged Pores and Sebaceous Hyperplasia
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