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PubMed1997

Increased scalp skin and serum 5 alpha-reductase reduced androgens in a man relevant to the acquired progressive kinky hair disorder and developing androgenetic alopecia.

BACKGROUND: The acquired progressive kinking of scalp hair is a disorder in which affected hairs resemble secondary sexual hairs. Some authors have evoked an androgen-related disorder that heralds the onset of androgenetic alopecia. To verify this hypothesis, we focused our attention on a 23-year-old man who has this unusual disorder, which is progressing toward androgenetic alopecia. Patient's circulating 5 alpha-reductase reduced androgen levels; scalp skin 5 alpha-dihydrotestosterone formation; and trichography, histological, scanning, and polarizing electron microscopy analyses were compared in normal and affected scalp skin areas. OBSERVATIONS: Results of histological and scalp skin 5 alpha-dihydrotestosterone formation analyses and comparison of growth pattern of kinky hair in the affected areas with that of healthy hair were similar to those found in androgenetic alopecia. CONCLUSIONS: No data are available to confirm the presence of a sole entity, even if our arguments support our hypothesis. The confirmation of this tendency warrants further investigation.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

PubMed1997

Carbon dioxide laser-assisted hair transplantation. The effect of laser parameters on scalp tissue--a histologic study.

BACKGROUND: "Char-free" carbon dioxide lasers are capable of precise tissue vaporization with minimum residual thermal damage. These lasers deliver very high bursts of energy for extremely short durations, and can vaporize recipient sites during hair transplantation, which are consistent in depth and diameter. OBJECTIVE: To determine the depth of ablation and lateral thermal damage of scalp tissue using various laser parameters with the Sharplan 80XJ Silklaser. METHODS: Two hundred forty laser recipient sites were created, using 24 different laser parameters in each of 10 specimens of scalp tissue removed during scalp reduction. These specimens were evaluated histologically for depth of ablation and lateral thermal damage. RESULTS: While some laser parameters worked better regarding consistent depth of ablation of scalp tissue, lateral thermal damage was quite narrow (average, 20-50 microns). CONCLUSIONS: None of the laser parameters tested in this study should be problematic when used clinically for hair transplantation.

Hair↗

PubMed1997

A controlled study of the effects of RU58841, a non-steroidal antiandrogen, on human hair production by balding scalp grafts maintained on testosterone-conditioned nude mice.

Human hair growth can be monitored for several months after the transplantation of scalp samples from men with androgen-dependent alopecia on to female nude mice. Hair production from balding sites has been shown to be inhibited in testosterone-conditioned nude mice. We used this recently reported model to study the effect of a new non-steroidal antiandrogen-RU58841-on human hair growth. Twenty productive scalp grafts from balding men were maintained for 8 months after grafting on to nude mice, and hair production was monitored monthly for 6 months. All mice were conditioned by the topical application of testosterone (testosterone propionate, 300 micrograms in 10 microL; 5 days/week) on the non-grafted flank. The scalp samples were divided equally according to the estimated hair production potential, which was based on the amount of hair present on the scalp samples before grafting. Each of the two equal groups of grafts was further allocated at random to be treated topically (5 days/week) with blinded solutions of either RU58841 1% in ethanol, or ethanol as a control. Twenty-eight active follicles appeared on the 10 control grafts. Among them only two follicles (7%) initiated a second hair cycle. However, the 10 RU58841-treated grafts bore a total of 29 active follicles, and eight of them (28%) showed a second cycle. The values for the linear hair growth rates (LHGR) were significantly (P < 0.04) higher in the RU58841-treated group. Recycling and increased LHGR indicate a positive action for RU58841 on human hair growth from balding samples grafted on to testosterone-conditioned nude mice, and encourage a clinical trial to evaluate its potential in the treatment of androgen-dependent alopecia.

Alopecia↗

PubMed1998

Localized crusted scabies of the scalp and feet.

An atypical case of crusted scabies in a patient with acquired immunodeficiency syndrome is presented in which lesions at the time of evaluation were confined to the scalp and feet. Because of the unusual presentation, the scalp involvement (which clinically mimicked seborrheic dermatitis) was initially missed. Although both the crusted variant of scabies and scabietic involvement of the scalp are well documented to occur in immunocompromised patients, to our knowledge scabies confined to the scalp and feet has not been previously reported.

AIDS-Related Opportunistic Infections↗

PubMed1976

[Scalp avulsion injuries (author's transl)].

In a recent scalp avulsion injury, the scalp should always be re-implanted without delay if at all available. Subsequent normal hair growth can hardly be expected, but at least an original skin replacement has been effected. The reconstruction of only a part of the scalp should be performed in such a way that the hairless area is situated in the centre. The surrounding hair will cover this centre part. Rotation flaps in the region of the scalp follow other rules than apply to all other areas of the body. If applied correctly, good results can be achieved because of the excellent blood supply.

Accidents↗

PubMed1984

Scalp potential fields evoked by grating stimuli: effects of spatial frequency and orientation.

Visually evoked potentials were recorded from an array of 16 electrodes over the occipital cortex in 12 subjects. Grating stimuli of different spatial frequencies were presented on a circular test field, and potential fields evoked by vertical, horizontal and oblique stimuli were compared. Component latencies were determined by computing a reference-independent measure of field power. Scalp field maps were constructed at component latencies and compared over all conditions. Significant influences of both spatial frequency and orientation on component latencies were found. Component latencies were shortest for 2.3 c/deg gratings, and for vertically oriented stimuli. Latencies increased for horizontal, and further for oblique, gratings. The effect of spatial frequency or orientation on the location of the major components on the scalp was less pronounced. On the other hand, there were significant differences both in component latency and scalp distribution when upper and lower hemiretinal stimuli were compared. Upper hemiretinal stimulation yielded shorter latencies and a more anteriorly located potential peak on the scalp.

Adult↗

PubMedDate not supplied

Origin of scalp far-field N18 of SSEPs in response to median nerve stimulation.

To identify the origin of scalp-recorded far-field negativity of short-latency somatosensory evoked potentials to median nerve stimulation (designated N18), direct records were made from the thalamus and ventricular system during 4 stereotaxic and 3 posterior fossa operations. In the thalamus a negative potential with almost the same latency as the scalp N18 was restricted to the Vim nucleus, but there was a large positive potential in the VC nucleus and medial lemniscus. Vim negativity increased in amplitude when high frequency stimulation was given to the median nerve, indicative of a facilitation effect. In contrast, the amplitude of scalp N18 decreased at high frequency stimulus. Direct recordings made through the medulla oblongata to the mid-brain showed a negative potential with gradually increasing latency. Above the upper pons, there was stationary negativity with no latency shift. The similarity between this negative potential and N18 is shown by their having the same latency and same response to the amplitude reduction and latency prolongation produced by high frequency stimulus. Our data suggest that scalp N18 comes from brain-stem activity between the upper pons and the mid-brain rather than from the thalamus.

Adult↗

PubMed1996

Event-related potential scalp fields during parallel and serial visual searches.

Event-related potential (ERP) scalp fields generated during parallel and serial searches were compared using a bootstrap resampling technique. Two different parallel search tasks required the detection of a single feature either color or orientation. A serial search task required the detection of the feature conjunction target: color and orientation. Identical stimuli were used for both parallel searches and a similar stimulus for the serial search. No evidence for scalp field differences earlier than 150 ms were discovered, suggesting that "low-level' visual processing is the same in both types of searches. ERP scalp fields that distinguished parallel from serial searches were identified between 150 and 250 ms. It is proposed that these different scalp fields represent timing and/or magnitude differences in the regions of cortex activated during parallel and serial searches.

Adult↗

PubMed2003

A disturbance of nonlinear interdependence in scalp EEG of subjects with first episode schizophrenia.

It has been proposed that schizophrenia arises through a disturbance of coupling between large-scale cortical systems. This "disconnection hypothesis" is tested by applying a measure of dynamical interdependence to scalp EEG data. EEG data were collected from 40 subjects with a first episode of schizophrenia and 40 matched healthy controls. An algorithm for the detection of dynamical interdependence was applied to six pairs of bipolar electrodes in each subject. The topographic organization of the interdependence was calculated and served as the principle measure of cortical integration. The rate of occurrence of dynamical interdependence did not statistically differ between subject groups at any of the sites. However, the topography across the scalp was significantly different between the two groups. Specifically, nonlinear interdependence tended to occur in larger concurrent "clusters" across the scalp in schizophrenia than in the healthy subjects. This disturbance was reflected most strongly in left intrahemispheric coupling and did not differ significantly according to symptomatology. Medication dose and subject arousal were not observed to be confounding factors. The study of dynamical interdependence in scalp EEG data does not support a straightforward interpretation of the disconnection hypothesis-that there is a decrease in the strength of functional coupling between adjacent cortical regions. Rather, it suggests a dysregulation in the organization of dynamical interactions across supraregional brain systems.

Adolescent↗

PubMed2003

Scalp ringworm in south-east London and an analysis of a cohort of patients from a paediatric dermatology department.

BACKGROUND: Scalp ringworm or tinea capitis has become an increasingly important public health issue in the past decade in Great Britain. Recently, certain dermatology departments in London have seen a large increase in tinea capitis in all its forms. OBJECTIVES: The aim of this paper is to present the detailed analysis of a cohort of 277 patients with tinea capitis seen during a 2-year period together with the latest local figures of tinea capitis cases from an inner city paediatric dermatology service. Methods Demographic, clinical and laboratory data were collected prospectively over 2 years from all cases of ringworm in patients seen in a paediatric clinic specially set up for scalp problems. RESULTS: Sixty-two per cent of 277 cases of scalp ringworm were caused by Trichophyton tonsurans, occurring mainly (91%) in patients with Afro-Caribbean hair type, more often in boys (68%), and in the 3-8 year olds (70%). Only 7% of the patients had received appropriate treatment with oral griseofulvin. An additional 156 cases from the general paediatric dermatology clinic showed 91%T. tonsurans infections. CONCLUSIONS: The prevalence of scalp ringworm appears to be reaching epidemic proportions in certain areas that include south-east London. The clinical problem is not yet well recognized by local general practitioners.

Age Distribution↗

PubMed2003

The effectiveness of scalp cooling in preventing alopecia for patients receiving epirubicin and docetaxel.

The aim of this study was to establish the effectiveness of scalp cooling in preventing alopecia for patients with breast cancer who received the trial combination chemotherapy of Epirubicin and Docetaxel. Doubt remains about the general effectiveness of scalp cooling in preventing hair loss for patients receiving chemotherapy. There is very little information available about its specific effectiveness with combinations of Taxanes and Anthracycline drugs. Of the 40 patients who received this drug combination, 10 were included in a pilot study whereas the remaining 30 constituted the main study sample. A randomized controlled study was undertaken whereby the intervention group received scalp cooling via gel cool caps and the control group received no specific preventative intervention. Nurses assessed participants' hair loss using a modified version of the WHO scale at seven time points and also recorded hair loss photographically. Two independent experts rated the photographs using the same scale. Patients self-reported in relation to overall hair loss, hair condition, levels of emotional upset, negativity about appearance, hair re-growth and wig use. Significantly greater hair loss was apparent in the control group during most of the treatment period. However, the level of protection afforded by the cool caps was relatively poor with this chemotherapy combination. The marginal benefits of scalp cooling in this context must be clearly explained to patients.

Alopecia↗

PubMedDate not supplied

A sporadic case of congenital hypotrichosis simplex of the scalp: difficulties in diagnosis and classification.

Hereditary hypotrichosis simplex of the scalp is a genotrichosis characterized by a hair defect limited to the scalp in the absence of other ectodermal or systemic abnormalities. Only large pedigrees consistent with autosomal dominant transmission have been described to date. In this article the clinical and scanning electron microscopy findings of a nonfamilial case of congenital scalp hypotrichosis simplex are reported. In some patients the diagnosis of sporadic hypotrichosis simplex of the scalp should be considered after ruling out all other possible causes of congenital and hereditary hypotrichosis.

Child, Preschool↗

PubMed2001

The effects of clonidine premedication and scalp infiltration of lidocaine on hemodynamic responses to laryngoscopy and skull pin head-holder insertion during skull base procedures.

This study was designed to determine if oral clonidine or lidocaine, injected into the scalp before head-holder (H-H) insertion, would attenuate the hemodynamic effects associated with intubation and H-H placement. Thirty-four patients undergoing skull base procedures were randomized to four groups. Group 1 received clonidine 5 mcg/kg po before surgery with 10 to 15 ml of 1% lidocaine infiltrated at pin insertion sites; Group 2 received clonidine with saline infiltration; Group 3 received a placebo preoperatively and had lidocaine infiltrated at pin sites; and Group 4 received a placebo with saline infiltrated. All patients had a standard anesthetic titrated to a 10 to 14 Hz EEG endpoint during laryngoscopy and H-H placement. Mean arterial pressure (MAP) was similar between groups during intubation, but heart rate (HR) increased in patients who did not receive clonidine. H-H application increased HR and MAP in Group 4. HR also increased after H-H placement in patients who received oral clonidine, while patients receiving scalp lidocaine or both clonidine and scalp lidocaine had little change in either value. Clonidine attenuated HR increases after laryngoscopy but not after H-H placement. Lidocaine injected at the pin sites reduced HR, and MAP increased after H-H insertion. The combination of oral clonidine and scalp lidocaine blunted hemodynamic responses to both intubation and H-H placement.

Journal Article↗

PubMed2001

A method to standardize a reference of scalp EEG recordings to a point at infinity.

The effect of an active reference in EEG recording is one of the oldest technical problems in EEG practice. In this paper, a method is proposed to approximately standardize the reference of scalp EEG recordings to a point at infinity. This method is based on the fact that the use of scalp potentials to determine the neural electrical activities or their equivalent sources does not depend on the reference, so we may approximately reconstruct the equivalent sources from scalp EEG recordings with a scalp point or average reference. Then the potentials referenced at infinity are approximately reconstructed from the equivalent sources. As a point at infinity is far from all the possible neural sources, this method may be considered as a reference electrode standardization technique (REST). The simulation studies performed with assumed neural sources included effects of electrode number, volume conductor model and noise on the performance of REST, and the significance of REST in EEG temporal analysis. The results showed that REST is potentially very effective for the most important superficial cortical region and the standardization could be especially important in recovering the temporal information of EEG recordings.

Algorithms↗

PubMed2003

'Bad hair days', scalp sebum excretion and the menstrual cycle.

BACKGROUND: Many women complain that their hair is periodically unmanageable, popularly known as 'bad hair days' (BHDs). At an anecdotal level BHDs are more common around the time of menstruation and, in view of previous studies reporting menstrual variation in sebum excretion, the authors hypothesised that changes in scalp sebum levels during the menstrual cycle might contribute to perceive differences in hair quality. AIMS: To test whether there is a relationship between BHDs, the menstrual cycle and scalp sebum excretion. METHODS: Thirteen women were studied through three menstrual cycles. Sebum levels on the scalp and forehead were measured twice weekly using a Sebumeter and each subject kept a record of hair quality and hair washing practice. RESULTS: BHDs occurred throughout the menstrual cycle but were more common during menstruation. There was no discernible variation in sebum levels on the scalp or forehead during the menstrual cycle and there was no correlation between individual mean skin sebum levels and the frequency of BHDs. However, BHDs were more common in those women who washed their hair infrequently, although the association between the frequency of hair washing and BHDs just failed to reach statistical significance (p = 0.06). CONCLUSIONS: BHDs are more common during menstruation and in women who wash their hair infrequently. This may relate to a build-up of sebum on the hair but menstrual variations in the frequency of BHDs are unrelated to sebum levels.

Journal Article↗

PubMed2005

Efficacy of a new antidandruff thermophobic foam: a randomized, controlled, investigator-blinded trial vs. ketoconazole 2% scalp fluid.

BACKGROUND: Ketoconazole (K), zinc pyrithione (ZP), and salicylic acid (SA) are compounds active in the treatment of dandruff. A thermophobic foam formulation containing K 1%, ZP 0.5%, and SA 2% is now available. STUDY AIM: To compare the efficacy of thermo phobic foam with K 2% scalp fluid in the treatment of moderate to severe dandruff. Patients and methods In a randomized, prospective, parallel-group, investigator-blinded, 4-week treatment trial, a total of 54 patients (mean age 43 +/- 8 years) were enrolled. Foam (F group) (n = 37) or K 2% scalp fluid (SF group) (n = 17) was applied daily for 7 days and twice weekly for 3 weeks thereafter. Clinical assessment of the total dandruff severity score (TDSS) was performed at baseline, after 2 and 4 weeks. The TDSS was calculated using a four-grade quantitative score (0 = no dandruff; 3 = severe dandruff) dividing the scalp area into four zones and adding the single score for each area. RESULTS: At baseline, TDSS was 7.1 +/- 2 and 5.1 +/- 1 in the F and SF groups, respectively. At the end of treatment period, beneficial effects were observed in both groups. The TDSS was reduced to 2.5 +/- 1 in the F group and to 3.7 +/- 1.2 in the SF group (mean difference in favor of F group: -1.2; 95% CI: -0.57 to -1.8) (P = 0.0003). A complete or nearly complete resolution of dandruff was observed in 24 out of 37 (64%: 95%CI: 48-77%) in the F group and in 7 out of 17 (41%: 95% CI: 21-64%) in the SF group (P = 0.06 between groups). CONCLUSIONS: This new antidandruff thermophobic foam has shown to be more effective than ketoconazole 2% scalp fluid in the treatment of severe dandruff.

Journal Article↗

PubMed2000

Interictal EEG and ictal scalp EEG propagation are highly predictive of surgical outcome in mesial temporal lobe epilepsy.

PURPOSE: Surgical outcome in patients with mesial temporal lobe sclerosis (MTS) is worse than that in patients with temporal lobe activity (TLE) with tumors. Previous studies of the ictal EEG focused on ictal EEG onset in scalp EEG or ictal EEG propagation in invasive recordings. Ictal EEG propagation with scalp electrodes has not been reported. METHODS: Ictal scalp EEG propagation patterns were studied in 347 seizures of 58 patients with MTS or nonlesional TLE. Interictal epileptiform discharges (IEDs) and the presence of unilateral mesial temporal lobe atrophy in magnetic resonance imaging (MRI) also were studied in these 58 patients. Forty-nine patients were operated on (minimal follow-up of 1 year). RESULTS: Postoperatively, seizure-free outcome was seen in (a) 82.8% of patients with regionalized EEG seizure without contralateral propagation, but in only 45.5% of patients with contralateral propagation (p = 0.007); (b) 84.6% of patients with 100% IED lateralized to one temporal lobe, but in only 52.2% with <100% unitemporal IED (p = 0.015); (c) 88.9% with 100% unitemporal IED and regionalized ictal EEG combined, 73.7% with one of both variables, and only 33.3% with <100% ipsitemporal IED combined with contralateral ictal EEG propagation (p = 0.007). CONCLUSIONS: Switch of lateralization or bitemporal asynchrony in the ictal scalp EEG and bitemporal IED are most probably an index of bitemporal epileptogenicity in MTS and are associated with a worse outcome.

Adolescent↗

PubMedDate not supplied

Readiness potentials recorded from the scalp and depth leads.

Readiness potentials on voluntary hand movements were recorded from the scalp (C3, C4), premotor cortex, subcortical white matter and VL nucleus of the thalamus. Subjects were healthy right-handed men and patients with involuntary movement disorders. We obtained a slow negative shift of brain electrical potentials from the scalp and cortex preceding voluntary hand movements. The mean time interval between the onset of the readiness potential and the onset of motor activity (mean T) was 0.8 sec on right hand movements and 1.0 sec on left hand movements in healthy men. In cases with parkinsonism, the mean T value was 1.4 sec in patients with akinesia, 1.1 sec in those without akinesia. The amplitude of readiness potentials was higher in the scalp contralateral to the hand movement. The readiness potentials recorded from the VL nucleus and white matter were reversed in polarity from those of scalp and cortex. Simultaneous recordings from cortex and VL nucleus showed early onset of readiness potentials from the cortex by approximately 0.1 sec compared with the VL nucleus.

Brain Mapping↗