Histologic and clinical cross-sectional study of chronic hair loss in patients with cutaneous chronic graft-versus-host disease.

BACKGROUND: While scalp alopecia represents a distinctive feature of chronic graft-versus-host disease (cGVHD), little is known about the clinical and histologic presentation of hair loss. OBJECTIVES: We sought to classify the clinical presentations and histologic findings of chronic hair loss in patients with cutaneous cGVHD. METHODS: A prospective cohort of 17 adult hematopoietic cell transplantation (HCT) recipients with cutaneous cGVHD was enrolled. Dermatologic examinations were performed, and punch biopsy specimens of the scalp were obtained. Biopsy specimens were analyzed with hematoxylin-eosin and immunohistochemical stains in all cases and fluorescence in situ hybridization analyses in specific cases. RESULTS: Clinically, 4 patterns of hair loss were described-patchy nonscarring (41.2%), diffuse nonscarring (11.8%), diffuse sclerotic (11.8%), and patchy sclerotic (5.9%). The location of the inflammatory infiltrate on hematoxylin-eosin-stained specimens correlated with the hair loss pattern patients had clinically, with cell populations around the bulb and bulge in nonscarring and sclerotic cases, respectively. Fluorescence in situ hybridization studies in female cGVHD patients with male donors demonstrated green Y chromosomes limited to the area of the hair follicle affected by inflammatory cells. CONCLUSION: This study describes the various clinical and histologic subtypes of long-standing alopecia in adult cGVHD patients and suggests that this alopecia may be a direct manifestation of cGVHD of the hair follicle.

Ictal and preictal power changes outside of the seizure focus correlate with seizure generalization.

OBJECTIVE: The treatment of focal epilepsies is largely predicated on the concept that there is a "focus" from which the seizure emanates. Yet, the physiological context that determines if and how ictal activity starts and propagates remains poorly understood. To delineate these phenomena more completely, we studied activity outside the seizure-onset zone prior to and during seizure initiation. METHODS: Stereotactic depth electrodes were implanted in 17 patients with longstanding pharmacoresistant epilepsy for lateralization and localization of the seizure-onset zone. Only seizures with focal onset in mesial temporal structures were used for analysis. Spectral analyses were used to quantify changes in delta, theta, alpha, beta, gamma, and high gamma frequency power, in regions inside and outside the area of seizure onset during both preictal and seizure initiation periods. RESULTS: In the 78 seizures examined, an average of 9.26% of the electrode contacts outside of the seizure focus demonstrated changes in power at seizure onset. Of interest, seizures that were secondarily generalized, on average, showed power changes in a greater number of extrafocus electrode contacts at seizure onset (16.7%) compared to seizures that remained focal (3.8%). The majority of these extrafocus changes occupied the delta and theta bands in electrodes placed in the ipsilateral, lateral temporal lobe. Preictally, we observed extrafocal high-frequency power decrements, which also correlated with seizure spread. SIGNIFICANCE: This widespread activity at and prior to the seizure-onset time further extends the notion of the ictogenic focus and its relationship to seizure spread. Further understanding of these extrafocus, periictal changes might help identify the neuronal dynamics underlying the initiation of seizures and how therapies can be devised to control seizure activity.

Streamlined, Inexpensive 3D Printing of the Brain and Skull.

Neuroimaging technologies such as Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) collect three-dimensional data (3D) that is typically viewed on two-dimensional (2D) screens. Actual 3D models, however, allow interaction with real objects such as implantable electrode grids, potentially improving patient specific neurosurgical planning and personalized clinical education. Desktop 3D printers can now produce relatively inexpensive, good quality prints. We describe our process for reliably generating life-sized 3D brain prints from MRIs and 3D skull prints from CTs. We have integrated a standardized, primarily open-source process for 3D printing brains and skulls. We describe how to convert clinical neuroimaging Digital Imaging and Communications in Medicine (DICOM) images to stereolithography (STL) files, a common 3D object file format that can be sent to 3D printing services. We additionally share how to convert these STL files to machine instruction gcode files, for reliable in-house printing on desktop, open-source 3D printers. We have successfully printed over 19 patient brain hemispheres from 7 patients on two different open-source desktop 3D printers. Each brain hemisphere costs approximately $3-4 in consumable plastic filament as described, and the total process takes 14-17 hours, almost all of which is unsupervised (preprocessing = 4-6 hr; printing = 9-11 hr, post-processing = <30 min). Printing a matching portion of a skull costs $1-5 in consumable plastic filament and takes less than 14 hr, in total. We have developed a streamlined, cost-effective process for 3D printing brain and skull models. We surveyed healthcare providers and patients who confirmed that rapid-prototype patient specific 3D models may help interdisciplinary surgical planning and patient education. The methods we describe can be applied for other clinical, research, and educational purposes.