Scalp Removal Research Articles

Non-invasive transcranial volumetric ultrasound localization microscopy of the rat brain with continuous, high volume-rate acquisition

Rationale: Structure and function of the microvasculature provides critical information about disease state, can be used to identify local regions of pathology, and has been shown to be an indicator of response to therapy. Improved methods of assessing the microvasculature with non-invasive imaging modalities such as ultrasound will have an impact in biomedical theranostics. Ultrasound localization microscopy (ULM) is a new technology which allows processing of ultrasound data for visualization of microvasculature at a resolution better than allowed by acoustic diffraction with traditional ultrasound systems. Previous application of this modality in brain imaging has required the use of invasive procedures, such as a craniotomy, skull-thinning, or scalp removal, all of which are not feasible for the purpose of longitudinal studies. Methods: The impact of ultrasound localization microscopy is expanded using a 1024 channel matrix array ultrasonic transducer, four synchronized programmable ultrasound systems with customized high-performance hardware and software, and high-performance GPUs for processing. The potential of the imaging hardware and processing approaches are demonstrated in-vivo. Results: Our unique implementation allows asynchronous acquisition and data transfer for uninterrupted data collection at an ultra-high fixed frame rate. Using these methods, the vasculature was imaged using 100,000 volumes continuously at a volume acquisition rate of 500 volumes per second. With ULM, we achieved a resolution of 31 µm, which is a resolution improvement on conventional ultrasound imaging by nearly a factor of ten, in 3-D. This was accomplished while imaging through the intact skull with no scalp removal, which demonstrates the utility of this method for longitudinal studies. Conclusions: The results demonstrate new capabilities to rapidly image and analyze complex vascular networks in 3-D volume space for structural and functional imaging in disease assessment, targeted therapeutic delivery, monitoring response to therapy, and other theranostic applications.

Neurocranial abnormalities in the Middle Pleistocene Homo erectus fossils from Hexian, China

AbstractThe Middle Pleistocene Homo erectus cranium from Hexian (Hexian 1, PA 830), in central eastern China, has been studied fairly extensively with respect to its evolutionary position. However, analysis of a series of neurocranial abnormalities identified on the Hexian fossil has never been attempted. Here, we present the first study of these abnormalities identified on the Hexian cranium, including (1) multiple breakages (including cracking) that fracture radially across the whole vault, caused by taphonomic modifications; (2) postmortem erosional lacunae with a matrix layer on the external surface of the supraorbital torus; (3) and two healed lesions with resorption and new bone formation on the back of the head, likely the result of trauma (tensile trauma to the scalp or partial scalp removal) or burning (with damage to the scalp and superficial neurocranium). The Hexian 1 individual was a young adult and had experienced multiple neurocranial alterations of antemortem traumatic lesions and postmortem taphonomic damage. The Hexian 1 specimen adds to the growing list of examples of bone surface modifications on Pleistocene hominin fossils across the Old World—a list that documents clearly the high level of risk experienced by Middle Pleistocene hominins.

Cerebral Effects of Commonly Used Vasopressor-Inotropes: A Study in Newborn Piglets

BackgroundDespite widespread use in sick infants, it is still debated whether vasopressor-inotropes have direct cerebral effects that might affect neurological outcome. We aimed to test direct cerebrovascular effects of three commonly used vasopressor-inotropes (adrenaline, dopamine and noradrenaline) by comparing the responses to those of nonpharmacologically induced increases in blood pressure. We also searched for reasons for a mismatch between the response in perfusion and oxygenation.MethodsTwenty-four piglets had long and short infusions of the three vasopressor-inotropes titrated to raise mean arterial blood pressure (MAP) 10 mmHg in random order. Nonpharmacological increases in MAP were induced by inflation of a balloon in the descending aorta. We measured cerebral oxygenation (near-infrared spectroscopy), perfusion (laser-Doppler), oxygen consumption (co-oximetry of arterial and superior sagittal sinus blood), and microvascular heterogeneity (side stream dark field video microscopy).ResultsVasopressor-inotropes increased cerebral oxygenation significantly less (p≤0.01) compared to non-pharmacological MAP increases, whereas perfusion was similar. Furthermore, cerebral total hemoglobin concentration increased significantly less during vasopressor-inotrope infusions (p = 0.001). These physiologic responses were identical between the three vasopressor-inotropes (p>0.05). Furthermore, they induced a mild, although insignificant increase in cerebral metabolism and microvascular heterogeneity (p>0.05). Removal of the scalp tissue did not influence the mismatch (p>0.05).ConclusionWe demonstrated a moderate vasopressor-inotrope induced mismatch between cerebral perfusion and oxygenation. Scalp removal did not affect this mismatch, why vasopressor-inotropes appear to have direct cerebral actions. The statistically nonsignificant increases in cerebral metabolism and/or microvascular heterogeneity may explain the mismatch. Alternatively, it may simply reflect a vasopressor-inotrope-induced decrease in the arterial-to-venous volume ratio as detected by near-infrared spectroscopy.

Automatic segmentation of white matter hyperintensities by an extended FitzHugh & nagumo reaction diffusion model

To evaluate the efficiency and reproducibility of the extended FitzHugh & Nagumo (FHN) reaction-diffusion model proposed in this study for white matter hyperintensities (WMH) segmentation. Five types of magnetic resonance T2-weighted fluid-attenuated inversion-recovery (T2FLAIR) images of 127 patients with different scanning parameters from five clinical scanner systems were selected for this study. After skull and scalp removal and denoise, the T2FLAIR images were processed by the proposed extended FHN model to obtain WMH. This new technique replaced the global threshold constant with a local threshold matrix. There was no significant difference between the segmentation results of the training set and the manual contouring against those between the test set and the manual contouring based on similarity index (SI) values (P = 0.5217). The SI values of the five types of T2FLAIR images were 86.0% ± 15.4%, 85.8% ± 10.5%, 84.1% ± 14.8%, 87.2% ± 14.6%, 86.3% ± 12.7%, respectively, comparing the segmentation results using the proposed method to the manual delineations. The overall SI value of the images was 86.5% ± 14.5%. This approach also demonstrated a better WMH segmentation performance over its classic form (P < 0.001). The proposed approach is efficient and could provide a more effective and convenient tool for clinical quantitative WMH analysis.

Possible cases of scalping from pre‐hispanic highland Peru

AbstractFor years, the pre‐Hispanic Chachapoya of Northern Peru have been described as the ‘Warriors of the Clouds’. A more detailed look at newly excavated osteological samples from the highland site of Kuelap allows us to better examine the types of traumatic injuries among the Chachapoya. This paper describes an individual with evidence of a recent scalp removal including cut marks encircling the vault and a large area of active inflammatory response due to exposure of the outer table. The degree of osseous response and a small area of healing indicate short‐term survival. A second fragmentary skull demonstrates similar features but more advanced healing. The location and patterning of the cut marks are consistent with North American Indian pre‐historic and historic cases of scalping. The skulls of these two individuals provide the first osteological evidence of scalp removal from a pre‐Hispanic South American Andean context, although it is difficult to determine the motivation whether for therapeutic treatment or trophy taking. These cases, along with other evidence of interpersonal violence and cranial trauma, serve to elucidate the possible volatile nature of cultural contact between this region and lowland Amazonian tribes, where scalps and trophy heads were commonly taken in raids. Copyright © 2009 John Wiley &amp; Sons, Ltd.

Tumor Mapping in 2 Large Multigenerational Families With CYLD Mutations

To comprehensively ascertain the extent and severity of clinical features in affected individuals from 2 large families with proven heterozygous mutations in the CYLD locus and to correlate these findings with the 3 appendageal tumor predisposition syndromes (familial cylindromatosis, Brooke-Spiegler syndrome, and multiple familial trichoepitheliomas) known to be associated with such germline mutations. Interfamilial and intrafamilial observational study. Tertiary genetic and dermatology referral center. Thirty-four individuals recruited from 2 large multigenerational families with CYLD mutations. Clinical details, history, and tumor maps were obtained from all participants; in 18, the information was corroborated by detailed clinical examination. Tumor density, distribution and histologic findings, associated medical conditions, patient symptoms, and impact of disease on quality of life. The severity of penetrance and phenotype varied within families. Although an approximately equal female to male predisposition was noted, 5 women and 1 man (of 26 patients surveyed [23%]) had undergone total scalp removal. The average age at onset was 16 years (range, 8-30 years). Symptoms reported by affected patients included painful tumors (in 12 of 23 patients [52%] who answered the question), conductive deafness, and sexual dysfunction. Of the 26 surveyed patients, tumors were noted on the scalp in 21 (81%), on the trunk in 18 (69%), and in the pubic area in 11 (42%). Tumor mapping provided clinical evidence that correlated with hormonally stimulated hair follicles being particularly vulnerable to loss of heterozygosity and tumor induction. The burden of disease at sites other than the head and neck appears to be underreported in the literature and greatly affects quality of life. Differentiation between the clinical diagnoses has little prognostic or clinical utility in genetic counseling, even within individuals from the same family. Thus, we suggest an encompassing diagnosis of "CYLD cutaneous syndrome." Finally, the clinical distribution of tumors suggests that hormonal factors may play an important role in tumor induction in these patients.

An ectocranial lesion on the middle Pleistocene human cranium from Hulu Cave, Nanjing, China

The earlier Middle Pleistocene human partial cranium from Hulu Cave, Tangshan, Nanjing (Hulu 1) exhibits an ectocranial lesion which covers most of the anterior neurocranium, largely between the temporal lines and extending from the supratoral sulcus to the anterior parietal bone. The endocranial surfaces and the remainder of the cranium (upper facial skeleton, lateral frontal bone, posterior parietal bones, and mid-occipital bone) are normal. The healed lesion exhibits both resorption and the laying down of new bone. Differential diagnosis suggests that the lesion was caused by either trauma (broad compressive trauma, tensile trauma to the scalp, or partial scalp removal) or burning (with damage to scalp and superficial neurocranium). Dietary deficiencies, infection, and neoplastic disorders do not fit the lesion characteristics. The Hulu 1 specimen therefore joins a growing sample of Pleistocene Homo remains with nonfatal and nontrivial disorders.

BrainSuite: An automated cortical surface identification tool

We describe a new magnetic resonance (MR) image analysis tool that produces cortical surface representations with spherical topology from MR images of the human brain. The tool provides a sequence of low-level operations in a single package that can produce accurate brain segmentations in clinical time. The tools include skull and scalp removal, image nonuniformity compensation, voxel-based tissue classification, topological correction, rendering, and editing functions. The collection of tools is designed to require minimal user interaction to produce cortical representations. In this paper we describe the theory of each stage of the cortical surface identification process. We then present classification validation results using real and phantom data. We also present a study of interoperator variability.

A reproducible method for automated extraction of brain volumes from 3D human head MR images.

An automated method for extracting brain volumes from three commonly acquired three-dimensional (3D) MR images (proton density, T1 weighted, and T2-weighted) of the human head is described. The procedure is divided into four levels: preprocessing, segmentation, scalp removal, and postprocessing. A user-provided reference point is the sole operator-dependent input required. The method's parameters were first optimized and then fixed and applied to 30 repeat data sets from 15 normal older adult subjects to investigate its reproducibility. Percent differences between total brain volumes (TBVs) for the subjects' repeated data sets ranged from .5% to 2.2%. We conclude that the method is both robust and reproducible and has the potential for wide application.