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A 62-year-old woman had a defect in the vertex of the scalp that was created by the excision of a basal cell carcinoma. This was closed with three local, hair-bearing, rhomboid flaps. This allowed us to reconstruct the natural whorl pattern of hair in this region.
Far-field somatosensory evoked potentials (SSEPs) after median nerve stimulation were recorded from scalp- (Fz), epidural- (ED) and intravascular electrodes (basilar artery [Bas]) to study the nature of the controversial N18a component of the widespread N18 potential. In healthy volunteers frequently an N18a potential was recorded at Fz. Simultaneous Fz and ED recordings at the pontomesencephalic junction as well as Bas-recordings at the caudal basilar artery showed N18a components identical in latency and shape. With intravascular recordings the shapes differed between the top of the basilar artery and the caudal artery recordings. These findings support the existence of a separate N18a potential. The generator of the N18a is likely to be localized within the upper brainstem.
Previously, electrical impedance tomography (EIT) has been used to image impedance decreases in the exposed cortex of rabbits during brain activity. These are due to increased blood volume at the site of the stimulated cortex; as blood has a lower impedance than brain, the impedance decreases. During human brain activity similar blood flow changes have been detected using positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). If blood volume also changes then the impedance of human cortex will change during brain activity; this could theoretically be imaged with EIT. EIT data were recorded from a ring of 16 scalp electrodes in 34 recordings in 19 adult volunteers before, during and after stimulation with (1) a visual stimulus produced by an 8 Hz oscillating checkerboard pattern or (2) sensory stimulation of the median nerve at the wrist by a 3 Hz electrical square wave stimulus. Reproducible impedance changes, with a similar timecourse to the stimulus, were seen in all experiments. Significant impedance changes were seen in 21 +/- 5% (n = 16, mean +/- SEM) and 19 +/- 3% (n = 18) of the electrode measurements for visual and somatosensory paradigms respectively. The reconstructed 2D EIT images showed reproducible impedance changes in the approximate region of the stimulated cortex in 7/16 visual and 5/18 somatosensory experiments. This demonstrates that reproducible impedance changes can be measured during human brain activity. The final images contained spatial noise; the reasons for this and strategies to reduce this in future are discussed.
Theories concerning the cause of right- or left-hand preference in humans vary from purely learned behavior, to solely genetics, to a combination of the two mechanisms. The cause of handedness and its relation to the biologically specified scalp hair-whorl rotation is determined here. The general public, consisting of mostly right-handers (RH), shows counterclockwise whorl rotation infrequently in 8.4% of individuals. Interestingly, non-right-handers (NRH, i.e., left-handers and ambidextrous) display a random mixture of clockwise and counterclockwise swirling patterns. Confirming this finding, in another independent sample of individuals chosen because of their counterclockwise rotation, one-half of them are NRH. These findings of coupling in RH and uncoupling in NRH unequivocally establish that these traits develop from a common genetic mechanism. Another result concerning handedness of the progeny of discordant monozygotic twins suggests that lefties are one gene apart from righties. Together, these results suggest (1) that a single gene controls handedness, whorl orientation, and twin concordance and discordance and (2) that neuronal and visceral (internal organs) forms of bilateral asymmetry are coded by separate sets of genetic pathways. The sociological impact of the study is discussed.
Uptake of aluminum (Al), cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) from aqueous solutions by human scalp hair (water/hair = 100:1) has been studied in the concentration range 0-50 mg/L. Hair metal levels were determined by a wet digestion procedure and atomic absorption spectrometry. Under conditions used, uptake followed a sigmoid concentration-response relationship. The order of binding capacity of hair to the metals was as follows: Al greater than Cd greater than Cu greater than Pb greater than Zn. Using logit transformation 50% saturation was evaluated at the following metal concentrations (hair metal concentration of saturation is given in parenthesis): 0.34 mg/L for Al (0.154 mg/g); 1.82 mg/L for Cd (0.363 mg/g); 2.21 mg/L for Cu (0.651 mg/g); 2.52 mg/L for Pb (0.986 mg/g); 23.84 mg/L for Zn (1.616 mg/g). Percentage elution of trace metals from hair after treatment with metal-enriched solutions by five different procedures ranged from 14.5 to 46.5% for Al, from 11.1 to 28.9% for Zn, from 11.5 to 28.4% for Pb, from 8.9 to 13.6% for Cd, and from 0.1 to 11.8% for Cu. In addition, trace element concentrations were measured in tap water samples and shampoos.
A 60-year-old woman presented with multicentric skin tumors of the head. The histologically proven hemangioendothelioma was bleeding as a result of disseminated coagulopathy. In addition to immunotherapy, 6 MeV electron beam radiotherapy was used for the purpose of hemostasis with a single portal, 20 x 20 cm in size, covering the whole scalp from the top of the head. The radiotherapy was discontinued after 39 Gy/13 fractions/20 days because of the progress in size of a peripheral tumor and the stability of coagulopathy. After another electron boost delivery by two portals focused to exophytic parietal and temporal tumors of 20 Gy/10 fractions, high dose rate brachytherapy with a surface mold technique was performed, 3 Gy/fraction, four fractions/week, for a total of 36 Gy. It induced partial regression of the tumor and complete recovery of platelet counts from 2.5 x 10(4) to 18.2 x 10(4). The tumor disappeared in 3 months. No late side effects occurred, except for permanent alopecia. The patient developed a cervical lymph node metastasis 1 year after and marginal recurrence 2 years after the initial treatment. Both recurrent tumors were successfully treated by 4 MV external photons of 60 Gy/20 fractions/46 days and electron beam irradiation of 60 Gy/20 fractions/29 days, respectively. She has remained disease free for 3 years after the initial presentation.
Leiomyosarcomas primary in the skin and subcutaneous tissue are rare neoplasms. Metastatic leiomyosarcomas in general are exceptional. The authors present herein clinical, histopathological, and ultrastructural findings in a case of several metastases to the scalp and back from a leiomyosarcoma primary in the uterus.
The ultrastructural and immunohistochemical characteristics of a high-grade epithelioid angiosarcoma of the scalp are reported. By light microscopy, the neoplasm simulated a poorly differentiated carcinoma, either primary or metastatic from some occult site. Immunohistochemical study, using a specific antibody against factor VIII-related antigen, was positive when direct immunofluorescence was applied to frozen specimens of the neoplasm. Application of immunoperoxidase (avidin-biotin complex method) on paraffin-embedded tissue using the same antibody was negative. Ultrastructually, the neoplasm had a prominent cytoskeleton of intermediate filaments, numerous pinocytotic vesicles, small intercellular lumina with microvilli on their surfaces, and characteristic intracytoplasmic vacuoles. A brief discussion of the differential diagnostic features is made.
Squamous-cell carcinoma may arise in scars of chronic discoid lupus erythematosus. Although there have been 19 cases reported previously, detailed histopathologic features of this entity have not been recorded. We report a patient with extensive chronic discoid lupus erythematosus involving the scalp with subsequent development of multiple squamous-cell carcinomas. The tumors were locally aggressive with recurrences and invasion into the underlying skull and dura. The patient died of respiratory failure 4 1/2 years after initial surgical treatment. There was no clinical evidence of metastasis. Squamous carcinoma arising in discoid lupus erythematosus can be regarded as a low-grade carcinoma. Although about 20% of patients developed local recurrences and metastasis developed in about 30%, fatality occurred in only two patients (10.5%). Pertinent literature is reviewed, and the histopathologic findings, differential diagnosis, and biologic behavior of this tumor are discussed.
We report a case of vulvar epithelioid sarcoma with metastases to the scalp, an inguinal lymph node, lungs, liver, and kidneys. Epithelioid sarcoma typically involves the extremities of young men and may be confused histologically with various benign and malignant processes. Only five cases of primary vulvar epithelioid sarcoma have been previously reported. The present case represents the first report of cutaneous metastases from this primary site. We also review the literature pertaining to the clinical, pathologic, and immunohistochemical features of this rare tumor.
We describe a case of giant trichoblastoma that had been present for many years on the scalp of a 69-year-old man. The specimen was examined histopathologically, immunohistochemically, and ultrastructurally. Histopathologic examination showed that neoplastic cells were arranged in different patterns from area to area, including rippled, adenoid, and palisading patterns. In some areas of the neoplasm, foci of sebaceous differentiation were also present. The ultrastructural characteristics of neoplastic cells support the notion that trichoblastomas are neoplasms composed mostly of follicular germinative cells.
A case of well-differentiated syringomatous carcinoma in a 50-year-old woman is reported. The tumor was located on the scalp and manifested as a slowly enlarging patch of alopecia. It was misdiagnosed as alopecia areata for years and subsequently was erroneously considered to be a benign syringoma on the basis of the results of a punch biopsy. When the correct diagnosis was made, the patient was referred to a plastic surgery department for the complete removal of her lesion.
The cutaneous ciliated cyst (CCC) is an unusual lesion found in young women that typically occurs on the lower extremities. This report describes a case of CCC arising in the scalp, a previously undescribed anatomic location for this lesion. In addition, positive nuclear staining for estrogen and progesterone receptors is demonstrated by immunohistochemical methods. Possible pathogenetic mechanisms are discussed.
Five cases of a distinctive benign soft tissue lesion of the scalp in patients ranging from 4 months to 40 years of age are described. Clinically, the lesions appeared as solitary, subcutaneous nodules suggestive of a cystic vascular malformation or other benign condition. Histologically, however, the lesions were characterized by a monotonous, pseudoinfiltrative proliferation of cuboidal epithelioid cells arranged in clusters within the dermis and subcutaneous tissue in intimate association with vessels, adipose tissue, and other connective tissue elements. A prominent feature in all cases was the presence of areas simulating freely anastomosing vascular channels lined by round to spindle-shaped, slightly hyperchromatic epithelioid cells reminiscent of angiosarcoma. Immunohistochemically, these cells were negative for factor VIII-related antigen and Ulex europaeus lectin but were strongly positive with vimentin and epithelial membrane antigen antibodies, this latter being in keeping with the immunohistochemical profile of meningothelial cells. The meningothelial nature of these cells was supported by the electron microscopic demonstration in one case of cells with complex, interdigitating cytoplasmic processes that were joined by scattered cell junctions and contained abundant intracytoplasmic intermediate filaments. The intimate admixture of meningothelial elements with haphazardly arranged connective tissue elements sets these lesions apart from cutaneous meningiomas and warrants their designation as hamartomas with an ectopic meningothelial component.
No single modality is appropriate for treatment of the huge invasive basal cell carcinoma. Mohs' chemosurgery is perhaps the most efficacious ablative method, but it must be supplemented by a reconstructive procedure in nearly all sizable lesions. A case history is presented of a patient with massive basal cell carcinoma involving the entire posterior scalp and deep tissues in which chemosurgical ablation and major staged reconstruction proceeded concurrently to a successful conclusion. The advantages of this approach are discussed.
A free inguinal flap was transferred to correct a skull and scalp defect following resection of squamous cell carcinoma.
We present a monopedicled diagonal frontoparietooccipital flap to reconstruct the pilous implant hemiline of the scalp. We use this design to obtain the greatest possible length, closing the donor site with an advancement flap.
We present some variations of the monopedicled flap with temporal pedicle, used for treatment of traumatic scalp alopecias of different origin. Emphasis is on the frontal region--the most important area aesthetically.