Anisotropic Morphing in Bistable Kirigami through Symmetry Breaking and Geometric Frustration.

Shape morphing in bistable kirigami enables remarkable functionalities appealing to a diverse range of applications across the spectrum of length scale. At the core of their shape shifting lies the architecture of their repeating unit, where highly deformable slits and quasi-rigid rotating units often exhibit multiple symmetries that confer isotropic deployment obeying uniform scaling transformation. In this work, symmetry breaking in bistable kirigami is investigated to access geometric frustration and anisotropic morphing, enabling arbitrarily scaled deployment in planar and spatial bistable domains. With an analysis on their symmetry properties complemented by a systematic investigation integrating semi-analytical derivations, numerical simulations, and experiments on elastic kirigami sheets, this work unveils the fundamental relations between slit symmetry, geometric frustration, and anisotropic bistable deployment. Furthermore, asymmetric kirigami units are leveraged in planar and flat-to-3D demonstrations to showcase the pivotal role of shear deformation in achieving target shapes and functions so far unattainable with uniformly stretchable kirigami. The insights provided in this work unveil the role of slit symmetry breaking in controlling the anisotropic bistable deployment of soft kirigami metamaterials, enriching the range of achievable functionalities for applications spanning deployable space structures, wearable technologies, and soft machines.

Osteochondroma of the coronoid process (Jacob's disease): an unusual cause of restricted jaw motion.

Osteochondromas are the most common benign bone tumor, most commonly found in the ends of long bones; however, they rarely involve facial bones, particularly the mandible. Osteochondromas involving the coronoid process have rarely been reported in the literature but pose a diagnostic dilemma. When large enough, osteochondromas of the mandibular coronoid process can form a joint with the zygomatic arch (Jacob's disease). This pseudoarticulation results in restricted jaw motion, which can clinically be mistaken for temporomandibular joint dysfunction. We report a case of a 39-year-old man with chronic restricted jaw motion undiagnosed for several years.

Nonenhancing brain metastases.

The hallmark radiological finding in metastatic brain disease is multiple enhancing lesions. We report a case of metastatic lung cancer to the brain with a lack of contrast enhancement. We believe that this unusual finding is due to inadvertent "treatment" of the metastases with the antiangiogenic agent bevacizumab (Avastin).

Common and unusual craniofacial manifestations of metastatic neuroblastoma.

Although neuroblastoma is a common childhood malignancy, which frequently metastasizes, involvement of the facial bones and paranasal sinuses are uncommonly reported in the literature. However, over the last several years, we have encountered an increasing number of cases of metastatic neuroblastoma to the central nervous system and head and neck. This article will review the common and uncommon imaging manifestations of metastatic neuroblastoma, with emphasis on the orbits, maxillofacial bones, and paranasal sinuses.

Imaging of metastatic CNS neuroblastoma.

OBJECTIVE: Although neuroblastoma is a common childhood malignancy, which frequently metastasizes, involvement of the CNS is rarely reported in the literature. However, over the past several years, we have encountered an increasing number of cases of metastatic neuroblastoma to the CNS. This metastatic potential and changing metastatic pattern may, in part, be due to advances in medical treatment, leading to prolonged survival. This article will review the common and uncommon manifestations of metastatic neuroblastoma with an emphasis on the skull, dura, brain, ventricles, and leptomeninges. CONCLUSION: Neuroblastoma has diverse manifestations including masquerading as primary neurologic disease. This disease must be considered in a child with any unexplained neurologic disorder. Realizing that neuroblastoma may represent the cause of neurologic disease in a child will lead to earlier diagnosis.

Craniofacial and intracranial manifestations of langerhans cell histiocytosis: report of findings in 100 patients.

OBJECTIVE: The purpose of this study was to review the craniofacial and intracranial clinical and radiologic manifestations of patients diagnosed with Langerhans cell histiocytosis (LCH). This report will compare the frequency of the various manifestations found in our series with those reported in the medical literature. CONCLUSION: In LCH, involvement of the calvaria, skull base, maxillofacial bones, and hypothalamic-pituitary axis is fairly common. The precise location of these lesions contributes to the variety of clinical manifestations of LCH, which includes scalp and/or facial swelling, seizures, hearing loss, recurrent otitis media, gingival bleeding, proptosis, diabetes insipidus, and cranial nerve palsies.

Spontaneous isolated dissection of the celiac artery: CT findings in adults.

OBJECTIVE: Our objective was to describe the CT features of spontaneous isolated celiac artery dissection in a series of six otherwise healthy patients with acute abdominal pain. CONCLUSION: Although once believed rare, isolated spontaneous celiac artery dissection should be considered in the diagnosis of acute abdominal pain, especially in middle-aged adults.