Clinical application of bone turnover markers in treating osteoporotic vertebral compression fractures and their role in predicting fracture progression.

This study aimed to investigate whether changes in the bone turnover markers (BTMs) during teriparatide therapy for osteoporotic vertebral compression fractures could reflect therapeutic effects by analyzing the relationship between clinical and radiological features and BTMs. A total of 33 patients with 51 osteoporotic vertebral compression fracture segments were included. Plain radiographs and BTM levels were evaluated at the pretreatment and at 3 months after teriparatide treatment. Based on serial vertebral compression ratio analysis, the progression of fracture was defined as a vertebral compression ratio decrease of ≥10%, relative to the pretreatment values. All segments were divided into 2 groups: the "maintain" group with 32 (62.7%) segments and the "progression" group with 19 (37.3%) segments. After the teriparatide treatment, serum osteocalcin and serum C-terminal telopeptide of type I collagen levels (P = .028 and .008, respectively), and change amounts of them were significantly larger, increasing (P = .001) in the progression group. The vitamin D (25OH-D) levels were significantly lower (P = .038) in the progression group; however, the relative changes in the 25OH-D levels between the 2 groups, before and after the treatment, were not significantly different (P = .077). The parathyroid hormone (PTH) levels were reduced by the teriparatide treatment in both groups, while the decrease in PTH concentration after the treatment was significantly more pronounced in the progression group (P = .006). Significant increase in the osteocalcin and serum C-terminal telopeptide of type I collagen levels and a simultaneous decrease in the PTH levels during the teriparatide treatment suggest that clinicians should assume the progression of fracture.

Risks and benefits of timely screw removal after thoracolumbar spine fractures treated with non-fusion technique.

BACKGROUND: Percutaneous-short segment screw fixation (SSSF) without bone fusion has proven to be a safe and effective modality for thoracolumbar spine fractures (TLSFs). When fracture consolidation is confirmed, pedicle screws are no longer essential, but clear indications for screw removal following fracture consolidation have not been established. METHODS: In total, we enrolled 31 patients with TLSFs who underwent screw removal following treatment using percutaneous-SSSF without fusion. Plain radiographs, taken at different intervals, measured local kyphosis using Cobb' angle (CA), vertebra body height (VBH), and the segmental motion angle (SMA). A visual analogue scale (VAS) and the Oswestry disability index (ODI) were applied pre-screw removal and at the last follow-up. RESULTS: The overall mean CA deteriorated by 1.58° (p < 0.05) and the overall mean VBH decreased by 0.52 mm (p = 0.001). SMA preservation was achieved in 18 patients (58.1%) and kyphotic recurrence occurred in 4 patients (12.9%). SMA preservation was statistically significant in patients who underwent screw removal within 12 months following the primary operation (p = 0.002). Kyphotic recurrence occurred in patients with a CA ≥ 20° at injury (p < 0.001) with a median interval of 16.5 months after screw removal. No patients reported worsening pain or an increased ODI score after screw removal. CONCLUSION: Screw removal within 12 months can be recommended for restoration of SMA with improvement in clinical outcomes. Although, TLSFs with CA ≥ 20° at the time of injury can help to predict kyphotic recurrence after screw removal, the clinical outcomes are less relevant.

Langerhans Cell Histiocytosis Involving Second Cervical Vertebra and the Hypothalamus and Pituitary in an Adult.

BACKGROUND: Adult-onset Langerhans cell histiocytosis (LCH) with simultaneous involvement of the high cervical spine and the hypothalamus is rare. CASE DESCRIPTION: We have reported a case of adult-onset LCH in the second cervical vertebra with bony destruction and subsequent diabetes insipidus due to simultaneous involvement of the hypothalamus and pituitary stalk. Magnetic resonance imaging of the hypothalamus and pituitary lesion and immunohistochemistry of the cervical lesion revealed LCH. Posterior fusion of the cervical spine (first, third, and fourth cervical vertebrae) was performed, followed by systemic chemotherapy. The cervical fusion was well maintained, and the patient achieved clinical remission. No new LCH lesion was found during the follow-up of >2 years. CONCLUSIONS: Patients with known LCH of the spine showing new symptoms of diabetes insipidus should be examined for infiltrating lesions of the pituitary stalk or hypothalamus. In cases of severe instability of the spine, surgical treatment should be performed. If multiple and systemic LCH lesions are found, systemic chemotherapy should be administered.

Thoracolumbar burst fractures in patients with neurological deficit: Anterior approach versus posterior percutaneous fixation with laminotomy.

BACKGROUND: Thoracolumbar burst fractures (TLBFs) are the most common spinal trauma; however, their appropriate management has not yet been determined. In this study, we aimed to compare the clinical and radiological results of percutaneous pedicle screw fixation (PPSF) following posterior decompression technique versus anterior corpectomy and fusion technique for the treatment of TLBFs. METHODS: A total of 46 patients (2002-2015) with TLBFs were included in this study. The inclusion criteria were a single-level Magerl type A3 burst fracture of the thoracolumbar junctional spine (T12-L2). The patients were divided into two groups; Group A (22 patients) underwent anterior corpectomy and fusion, and Group B (24 patients) underwent PPSF after posterior decompression. Anterior corpectomy and fusion surgery were performed in 22 cases before April 2009, and PPSF following posterior decompression technique was used in 24 cases since then. For radiological assessment, the kyphosis angle was measured preoperatively, early postoperatively, and at the last follow-up using the Cobb angle. Mean correction of the Cobb angle after surgery, and loss of correction between the immediate postoperative and final Cobb angle were calculated accordingly. All neurological deficits were identified in the initial evaluation and graded using the American Spinal Injury Association(ASIA) grading system. Perioperative parameters including operation time, amount of blood loss, and mean hospital stay were also evaluated. RESULTS: The patients comprised 17 males and 5 females in Group A and 13 males and 11 females in Group B. In terms of the involved levels, there were three cases of T12, twelve L1, and seven L2 in Group A and one case of T12, thirteen L1, and ten L2 in Group B. The mean follow-up duration was 44.9 months in Group A and 14.7 months in Group B. The kyphotic angle was significantly corrected after surgery by 6.4° in Group A (p = 0.001) and 9.2° in Group B (p < 0.001). Among patients with neurological deficit, 11 of 15 in Group A and 20 of 23 in Group B demonstrated improvement by at least one ASIA grade at the final observation. However, there was no significant difference in neurological improvement between the two groups (p = 0.13). Mean operation time was significantly shorter (p < 0.001) and mean blood loss was significantly less (p < 0.001) in Group B than in Group A. Mean hospital stay was also significantly shorter in Group B (p < 0.001). CONCLUSIONS: Spinal canal decompression through small laminectomy followed by PPSF in the treatment of TLBFs with neurological deficits offers excellent clinical and radiological improvement as well as biomechanical stability. Furthermore, this can be a safe and effective surgical option with the advantage of less invasiveness in the treatment of TLBFs.

Stress Release Effect of Micro-hole Arrays for Flexible Electrodes and Thin Film Transistors.

The effects of micro-hole arrays in the thin metal films were studied as a method to release bending stress in flexible electrodes and flexible thin film transistors (TFTs). Interest in flexible electronics is increasing, and many approaches have been suggested to solve the issue of the electrical failure of electrodes or electrical components such as TFTs after repeated bending. Here, we demonstrate a micro-hole array structure as a common solution to release bending stress. Although micro-size cracks were generated and propagated from the hole edges, the cracks stopped within a certain range when enough stress was released. Moreover, since the crack sites were predictable and controllable, a fatal electrical breakdown in a conductive layer such as a metal electrode or the semiconducting junction of a TFT can be prevented by specifically arranging the hole arrays. Thin film layers fabricated without holes suffered an electrical breakdown due to random crack propagation during bending tests. Aluminum thin film electrodes prepared with arrays of 3 µm diameter holes and 25% hole area showed excellent durability after 300,000 bending cycles. The change in resistance was below 3%. The electrical characteristics of an a-IGZO TFT with the micro-hole structure were almost equivalent to a standard a-IGZO TFT. After 10,000 bending cycles, ION and the ratio of ION/IOFF remained >107 A and ∼107, respectively. Since the effective hole diameter is micrometer in size, fabrication does not require additional process steps or expensive process equipment. Therefore, the approach can be an important way to enhance the reliability of various electrical devices in flexible and wearable applications.

Unexpected Intradural Lumbar Disk Herniation Found During Transforaminal Endoscopic Surgery.

BACKGROUND: Intradural disk herniation (IDH) is defined as the displacement of the intervertebral disk nucleus pulposus into the dural sac. In this lumbar lesion, the affected level differs from that of a traditional extradural herniation: 55% of cases occur at the level of L4-5, 16% at L3-4, and 10% at L5-S1. Upper lumbar IDH is extremely rare. We present a case of an IDH at the level of L2-3 that was diagnosed during endoscopic surgery. CASE DESCRIPTION: A 65-year-old male patient presented with severe radiating pain in the anterior right thigh that was accompanied by a tingling sensation in the right calf and difficulty in walking. Physical examination showed normal strength. Bladder and bowel function was normal, but mild hypesthesia of the L3 sensory dermatome was observed. Magnetic resonance imaging revealed a herniated disk at the level of L2-L3 that was compressing the right side of the dura. A percutaneous transforaminal endoscopic lumbar diskectomy was planned. After foraminoplasty, no ruptured disk fragments could be found. During dissection of the adhesion between the dura and protruded disk, the dura was torn. Interestingly, through this dural opening, multiple fragmented disk portions were visualized among the nerve rootlets. We removed some of the soft disk material; however, complete removal of the disk fragments was predicted to damage the rootlets, and we decided to convert to microscopic surgery. The disk fragments were successfully removed via durotomy under microscopic assistance. The incised dorsal dura was primarily sutured with continuous stitches, and the defect on the ventrolateral side of the dura was patched and sealed using a harvested inner ligamentum flavum and Gelfoam (Pfizer, New York, New York, USA). After the operation, the patient's symptoms improved. There was no cerebrospinal fluid leakage. CONCLUSIONS: If there is any preoperative clinical or radiologic suspicion of IDH, a microscopic surgical approach should be considered to be the first-line option, as this is a safe and effective method for achieving IDH removal and dura repair without a postoperative neurologic deficit. Even during endoscopic surgery, if the surgeon expects even minor complications, we suggest converting to open surgery. In addition, the adequate sealing of the dura may be sufficient to prevent cerebrospinal fluid leakage, without the need for dural suture and lumbar drainage.

Outcomes of Anterior Cervical Fusion Using Polyetheretherketone Cage with Demineralized Bone Matrix and Plate for Management of Subaxial Cervical Spine Injuries.

OBJECTIVE: We evaluated the usefulness of a polyetheretherketone (PEEK) cage filled with demineralized bone matrix (DBM) and plate fixation in anterior interbody fusions for subaxial cervical spine injuries. METHODS: A retrospective review of 98 patients (58 women, 40 men; mean age, 49.7 years; range, 17-78 years) who underwent single-level anterior cervical discectomy and fusion (ACDF) using a PEEK cage filled with DBM and plate fixation for subaxial cervical spine injuries from March 2005 to June 2018 was conducted. Bone fusion, interbody height (IBH), segmental lordosis, and adjacent segment degeneration (ASD) development were assessed with plain radiographs and computed tomography. Clinical outcomes were assessed using a visual analog scale (VAS) for pain and the Frankel grade for neurologic function. RESULTS: The mean follow-up period was 27.6 months (range, 6-142 months). Twenty-one patients (21.4%) had an improvement of at least one Frankel grade. The mean preoperative and final follow-up neck pain VAS scores were 8.3±0.9 and 2.6±1.5 (p<0.05). All patients showed solid fusion at the final follow-up. The mean preoperative and final Cobb's angles were -3.7±7.9° and 1.9±5.1° (p<0.05). The mean preoperative and final IBHs were 36.9±1.7 mm and 38.2±1.8 mm (p<0.05). Five patients (5%) showed ASD. CONCLUSION: ACDF using a PEEK cage filled with DBM and plate fixation yielded high fusion rates and satisfactory clinical outcomes without donor-site morbidity. This procedure is safe and effective for single-level subaxial cervical spine injuries.

Ruptured choroidal artery aneurysms in patients with moyamoya disease: Two case series and review of the literatures.

Distal peripheral artery aneurysms in moyamoya disease (MMD) remain difficult to treat given their deep location, small size, and fragility. Here, we report two cases of choroidal artery aneurysms associated with MMD who were treated through direct clipping and coil embolization. Timing of aneurysm formation remains unclear, however, annual follow-up DSA for surveillance of hemodynamic status is necessary and prompt treatment of aneurysm should be performed when diagnosed. Moreover, choroidal artery aneurysms may benefit from endovascular coil embolization due to their characteristics.

Wireless thin film transistor based on micro magnetic induction coupling antenna.

A wireless thin film transistor (TFT) structure in which a source/drain or a gate is connected directly to a micro antenna to receive or transmit signals or power can be an important building block, acting as an electrical switch, a rectifier or an amplifier, for various electronics as well as microelectronics, since it allows simple connection with other devices, unlike conventional wire connections. An amorphous indium gallium zinc oxide (α-IGZO) TFT with magnetic antenna structure was fabricated and studied for this purpose. To enhance the induction coupling efficiency while maintaining the same small antenna size, a magnetic core structure consisting of Ni and nanowires was formed under the antenna. With the micro-antenna connected to a source/drain or a gate of the TFT, working electrical signals were well controlled. The results demonstrated the device as an alternative solution to existing wire connections which cause a number of problems in various fields such as flexible/wearable devices, body implanted devices, micro/nano robots, and sensors for the 'internet of things' (IoT).

Differences in the clinical courses of pediatric and adult pilocytic astrocytomas with progression: a single-institution study.

PURPOSE: Pilocytic astrocytoma (PA) is a World Health Organization grade I neoplasm that generally follows a benign course. However, in some patients, PA exhibits an aggressive clinical course. Here, we examined the clinical course of pediatric and adult PAs with progression at a single institution. METHODS: Between 1995 and 2013, 39 patients with PA were treated. Nineteen were pediatric patients (mean age, 12 years; range, 1-17 years) with a male-to-female patient ratio of 10:9, while 20 were adults (mean age, 36.4 years; range, 19-65 years) with a male-to-female ratio of 9:11. We analyzed and compared tumor location, extent of tumor resection, adjuvant treatment, and clinical course in all patients. RESULTS: In the 19 pediatric patients, tumors were located in the cerebellar vermis, cerebellar hemisphere, optic pathways plus hypothalamus, hypothalamus, brainstem, and the temporal lobe in 6 (31.6%), 5 (26.3%), 3 (15.8%), 2 (10.5%), and 2 (10.5%) patients and 1 (5.3%) patient, respectively. The mass was totally, subtotally, or partially resected in 11 (57.9%), 2 (10.5%), and 4 (21.1%) patients, respectively; biopsies were performed in 2 (10.5%) patients. Immediate postoperative adjuvant treatment was carried out in 6 patients. Tumor progression was detected in 3 patients at 3.0, 4.6, and 5.2 years after treatment, respectively, without significant symptoms. In the 20 adult patients, tumors were located in the cerebellar hemisphere, cerebellar vermis, hypothalamus, brainstem, cerebral hemisphere, and lateral ventricle in 5 (25%), 4 (20%), 3 (15%), 3 (15%), 3 (15%), and 2 (10%) patients, respectively. The mass was totally, subtotally, or partially resected in 11 (55%) and 6 (30%) patients and 1 (5%) patient, respectively; biopsies were performed in 2 patients. Immediate adjuvant treatment was carried out in 2 patients. Progression was detected in 3 patients at 0.3, 0.9, and 2.5 years after treatment, respectively, with progressive neurologic symptoms. There was one case of disease-related mortality during follow-up among the adult patients. CONCLUSION: Most of the PA cases evaluated in this study were benign. However, tumor progression in adult PAs followed a more aggressive clinical course than those in pediatric PAs.

The clinical experience of recurrent central nervous system hemangioblastomas.

OBJECTIVE: Hemangioblastomas (HBLs) of the central nervous system are benign vascular tumors that may occur sporadically or in von Hippel-Lindau disease (VHLD). We analyzed the clinical and radiological findings of HBLs focusing on recurrence. MATERIAL AND METHODS: From 1998 to 2012, 36 patients with HBLs were treated. Twenty nine patients (80.6%, mean age 46.7 years) had sporadic HBLs and seven (19.4%, mean age 39 years) had HBLs associated with VHLD. Initially, the mass was totally removed in 32 patients, subtotally in one and partially in one, and gamma knife radiosurgery was done in two patients. The mean duration of follow-up was 48.4 months. We retrospectively analyzed the clinical and radiologic findings. RESULTS: The location of cerebellum and brainstem was common. The HBLs of spinal cord and cerebral hemisphere were related with VHLD. The common radiologic findings of sporadic HBLs showed a cyst with a mural nodule in 15 patients (51.7%) and pure solid lesion in eight (27.6%). In HBLs related with VHLD, five of seven patients had multiple lesions and pure solid mass was common. Three (10.3%) and two (28.6%) patients showed recurrence in sporadic and VHLD-related HBLs, respectively. Two totally resected mural nodules on the cyst showed recurrence with similar radiologic findings 3 years later in sporadic HBLs. In recurred HBLs related with VHLD, one pure solid mass and one mural nodule on cyst showed the local recurrences after the total resection 8 years later and associated with distant recurrence. CONCLUSIONS: All patients should be more specifically followed to detect local and distant recurrence, even if the clinical course was benign and mass was totally removed.

Comparison of Clinical and Radiologic Results between Expandable Cages and Titanium Mesh Cages for Thoracolumbar Burst Fracture.

OBJECTIVE: A thoracolumbar burst fracture is usually unstable and can cause neurological deficits and angular deformity. Patients with unstable thoracolumbar burst fracture usually need surgery for decompression of the spinal canal, correction of the angular deformity, and stabilization of the spinal column. We compared two struts, titanium mesh cages (TMCs) and expandable cages. METHODS: 33 patients, who underwent anterior thoracolumbar reconstruction using either TMCs (n=16) or expandable cages (n=17) between June 2000 and September 2011 were included in this study. Clinical outcome was measured by visual analogue scale (VAS), American Spinal Injury Association (ASIA) scale and Low Back Outcome Score (LBOS) for functional neurological evaluation. The Cobb angle, body height of the fractured vertebra, the operation time and amount of intra-operative bleeding were measured in both groups. RESULTS: In the expandable cage group, operation time and amount of intraoperative blood loss were lower than that in the TMC group. The mean VAS scores and LBOS in both groups were improved, but no significant difference. Cobb angle was corrected higher than that in expandable cage group from postoperative to the last follow-up. The change in Cobb angles between preoperative, postoperative, and the last follow-up did not show any significant difference. There was no difference in the subsidence of anterior body height between both groups. CONCLUSION: There was no significant difference in the change in Cobb angles with an inter-group comparison, the expandable cage group showed better results in loss of kyphosis correction, operation time, and amount of intraoperative blood loss.

Cerebral aspergillosis with multiple enhancing nodules in the right cerebral hemisphere in the immune-competent patient.

Aspergillosis in the central nervous system (CNS) is a very rare disease in immune-competent patients. There was a case of a healthy man without a history of immune-compromised disease who had invasive aspergillosis with unusual radiologic findings. A 48-year-old healthy man with diabetes mellitus, presented with complaints of blurred vision that persisted for one month. Brain magnetic resonance imaging (MRI) showed multiple nodular enhancing lesions on the right cerebral hemisphere. The diffusion image appeared in a high-signal intensity in these areas. Cerebrospinal fluid examination did not show any infection signs. An open biopsy was done and intraoperative findings showed grayish inflammatory and necrotic tissue without a definitive mass lesion. The pathologic result was a brain abscess caused by fungal infection, morphologically aspergillus. Antifungal agents (Amphotericin B, Ambisome and Voriconazole) were used for treatment for 3 months. The visual symptoms improved. There was no recurrence or abscess pocket, but the remaining focal enhanced lesions were visible in the right temporal and occipital area at a one year follow-up MRI. This immune-competent patient showed multiple enhancing CNS aspergillosis in the cerebral hemisphere, which had a good outcome with antifungal agents.