Discover the most talked about and latest scientific content & concepts.

Concept: Scalp


Body hair shafts from the beard, trunk, and extremities can be used to treat baldness when patients have inadequate amounts of scalp donor hair, but reports in the literature concerning use of body hair to treat baldness are confined to case reports.

Concepts: Human body, Hair, Hair transplantation, Scalp, Facial hair, Follicular unit transplantation, Follicular Unit Extraction, Beard


Follicular unit transplantation is the most commonly performed technique in modern restorative hair transplantation surgery. It relies on the acquisition of intact follicular units from microdissected scalp skin strips and their subsequent transplantation into the recipient regions affected by alopecia. Ideally, the translocation of follicular units from the balding-resistant areas of the scalp (usually the occipital region) to the recipient site should not result in any morphological change in the grafts. Nevertheless, the insults associated with surgical intervention present grafted follicles to mechanical and chemical cues differently from those of the physiological steady-state conditions in undamaged skin. This disruption of the normal follicular microenvironment might alter important aspects of hair biology in grafts, for example, hair cycle and pigmentation, and, in turn, could lead to differences in hair appearance, eventually culminating in a diminished esthetical outcome of the surgery. In this study, the authors analyzed native and grafted scalp hair follicles (HFs) from 2 patients who had undergone follicular unit transplantation surgeries formerly. Scanning electron microscopy and light microscopy-based histomorphometry revealed a marked enlargement of follicular structures in the grafts with a concomitant increase in hair shaft diameter. Immunohistological staining confirmed a thickening of the dermal sheath in transplanted HFs that also harbored a denser vascular network. Taken together, these results show that the grafted HFs analyzed were subjected to marked morphological changes during their residence in the recipient site and that this phenomenon is associated with a modulation of follicular vascularization.

Concepts: Surgery, Chemotherapy, Skin, Hair, Hair follicle, Scalp, Follicular unit transplantation, Follicular Unit Extraction


Limited information is available about the anatomical feasibility and clinical applications of flaps based on distal divisions of the superficial temporal artery (STA). The aim of this study was to investigate the anatomy of the STA, focusing on the number and reliability of distal branches and to show representative cases for the use of such flaps for zygomatic, parieto-frontal and occipital reconstructions.

Concepts: External carotid artery, Anatomy, Human anatomy, Scalp, Temple, Superficial temporal artery


In this 3-dimensional video, we perform a side-to-side and end-to-side double anastomosis using the parietal-branch of the superficial temporal artery (STA) to provide flow augmentation in a symptomatic 59-yr-old male with bilateral internal carotid artery occlusion at the origin, and left M1 segment occlusion. The patient suffered multiple left hemispheric strokes despite maximal medical therapy and was found to have poor hemodynamic reserve in the left hemisphere during evaluation with regional and global blood oxygenation level-dependent functional magnetic resonance imaging with CO2-challenge as well as quantitative magnetic resonance angiography and noninvasive optimal vessel analysis pre- and post-acetazolamide challenge. Postoperatively, the patient did very well and his hemodynamic studies improved significantly. The importance of this technique relies on the fact that we are using a single donor vessel to perform 2 anastomoses, and carries the following advantages: (1) the frontal STA branch remains intact and therefore can still be used at a later time if further revascularization is needed; (2) wound complications related to devascularizing the scalp from harvesting both STA branches are reduced; (3) 2 vascular territories are augmented (frontal and temporal) while using a single donor; (4) we are maximizing donor potential and optimizing cut flow index (CFI; total bypass flow postanastomosis divided by bypass cut flow) by flow augmenting 2 separate vascular beds therefore increasing demand. To explain that fourth point further: if the STA donor is able to carry a maximum 100 mL/min when cut, and after performing the first anastomosis bypass flow is only 37 mL/min, CFI will be 37/100 = 0.37, reflecting low demand, a poor indicator of graft patency, as previously published.1,2 By adding a second anastomosis which demands an additional 60 mL/min from the same STA donor, CFI (60 + 37)/100 improves to 1. Institutional Review Board approval was obtained for the review of patient chart and video files. Informed consent was obtained directly from the patient via telephone regarding use of media for educational and publication purposes.

Concepts: Medical imaging, Magnetic resonance imaging, Common carotid artery, External carotid artery, Arteries of the head and neck, Scalp, Temple, Superficial temporal artery


There is increasing evidence for weight-based discrimination against persons with obesity. This study aimed to examine the physiological impact of perceived weight discrimination on cortisol in hair, an indicator of chronic stress exposure.

Concepts: Anxiety, Metabolic syndrome, Stress, Scalp, Scalping


Low level laser therapy (LLLT) has been used to promote hair growth. A double-blind randomized controlled trial was undertaken to define the safety and physiologic effects of LLLT on males with androgenic alopecia.

Concepts: Randomized controlled trial, Laser, Avicenna, Infrared, Visible spectrum, Scalp, Alopecia, Androgenic alopecia


Giant cell arteritis typically involves the temporal arteries, but can involve other cranial arteries. Temporal artery biopsy is the mainstay for the diagnosis of giant cell arteritis; however, biopsy may be problematic if giant cell arteritis involves other cranial arteries that are inaccessible for sampling. In these situations, magnetic resonance angiography is a useful, non-invasive adjunctive method in the diagnosis of giant cell arteritis. In this case report, we describe a case of giant cell arteritis involving only the occipital artery which was revealed by magnetic resonance angiography.

Concepts: Atherosclerosis, Atheroma, Medical imaging, External carotid artery, Arteries of the head and neck, Scalp, Giant cell arteritis, Temple


Adversity early in life can disrupt the functioning of the hypothalamic-pituitary-adrenal axis (HPAA) and increase risk for negative health outcomes. Recent research suggests that cortisol in scalp hair represents a promising measure of HPAA function. However, little is known about the relationship between early exposure to traumatic events and hair cortisol concentrations (HCC) in childhood, a critical period of HPAA development. The current study measured HCC in scalp hair samples collected from 70 community-based children (14 males, mean age=9.50) participating in the Imaging Brain Development in the Childhood to Adolescence Transition Study (iCATS). Data were also collected on lifetime exposure to traumatic events and current depressive symptoms. Lifetime exposure to trauma was associated with elevated HCC; however, HCC was not associated with current depressive symptoms. Consistent with some prior work, males were found to have higher HCC than females, although results should be treated with caution due to the small number of males who took part. Our findings suggest that hair cortisol may represent a biomarker of exposure to trauma in this age group; however, further study is necessary with a particular focus on the characterization of trauma and other forms of adversity.

Concepts: Measurement, Childhood, Developmental psychology, The Current, Scalp, Critical period


Successful total scalp replantation was performed in our case. Based on the angiosome concept and anatomical study, the avulsed scalp survived with unilateral anastomosis of the superficial temporal artery and superficial temporal vein, largely due to the presence of rich arterial and venous arcades in the scalp. The patient currently has no problems with activities of daily living, although total hypoaesthesia and dysfunction of the left frontal muscle of the forehead are present. In addition, the combined findings of hair growth pattern indicated the vascular territories of the scalp skin.

Concepts: Blood, Heart, Artery, Vein, Scalp, Temple, Superficial temporal artery, Superficial temporal vein


With the current tendency of increasing minimally invasive cosmetic surgeries, some rare but disastrous complications of facial filler injections come into sight, such as visual loss. The study aims to investigate the possible route that the injected droplet accesses the ophthalmic artery to explain and prevent such devastating complications. We searched the National Library of Medicine’s PubMed database for cases of visual loss secondary to cosmetic facial filler injection, and reviewed relevant case reports/surveys, as well as accompanying references. Data obtained were analyzed, with special interest in injected sites and filler material, and clinical features of visual loss. Based on the anatomy of facial vessels, we inferred the possible route of injected droplet migrating from injection sites to ophthalmic artery. Most physicians propose a retrograde embolic mechanism, but the culprit artery when injecting different sites is not determined. We consider accidentally breaking into supraorbital artery or supratrochlear artery may cause occlusion of ophthalmic artery when injecting into glabella or forehead region. Speaking of the nasolabial fold and nasal dorsum region, any injections in the anastomosis of the dorsal nasal artery, angular artery, and lateral nasal artery can lead to retrograde embolism. Similarly, in the temporal region, we believe there is abnormal anastomosis between frontal branch of superficial temporal artery from external carotid artery and supraorbital artery from ophthalmic artery. In our hypothesis, we can explain the accompanying brain infarction after iatrogenic visual loss. If the injecting pressure is forceful enough, it may push the embolic materials into middle cerebral artery. Although iatrogenic ophthalmic artery occlusion is a rare complication after the facial filler injection surgery, it is usually devastating. Both the patient and the surgeon should be aware of the risk of irreversible blindness. Ideally, the injection sites should avoid the small vessels nearby, the injecting force and velocity should be as gentle and slow as possible.

Concepts: Internal carotid artery, External carotid artery, Arteries of the head and neck, Parotid gland, Scalp, Ophthalmic artery, Superficial temporal artery, Facial artery