Navigated Hybrid Open/Muscle-sparing Approach to 2-level Cement Augmentation of the UIV and UIV+1 for Prevention of Proximal Junctional Failure: Supplemental Manuscript to Operative Video.

STUDY DESIGN: Operative video and supplemental manuscript. OBJECTIVE: To present a cement augmentation technique of the upper instrumented vertebra (UIV) and UIV+1 for prevention of proximal junctional fractures (PJFs) in multi-level thoracolumbar posterior instrumented fusions. SUMMARY OF BACKGROUND DATA: PJFs are unfortunately a common occurrence after multi-level thoracolumbar instrumented fusions to the pelvis for adult spinal deformity that can result in significant functional disability and often require costly revision operations. As such, their prevention is key. METHODS: A surgical video illustrates the nuances of a 2-level cement augmentation technique, consisting of an open vertebroplasty of the UIV through fenestrated screws and a muscle-sparing kyphoplasty of the UIV+1. RESULTS: Utility of performing an open vertebroplasty of the UIV through fenestrated screws and muscle-sparing kyphoplasty of the UIV+1 lies in its ability to minimize soft-tissue disruption at the adjacent segment while providing additional structural support to the anterior column at this high-risk zone. CONCLUSIONS: Cement augmentation of the UIV and UIV+1 consisting of a hybrid open vertebroplasty and muscle-sparing kyphoplasty can be an effective strategy to decrease the incidence of PJF after multi-level posterior thoracolumbar instrumented fusions to the pelvis for adult spinal deformity.

Coupling effect of superfine zeolite and fiber on enhancing the long-term performance of stabilized/solidified Pb-contaminated clayey soils.

The focus of the present study was on the applicability of superfine zeolite (SZ) and polypropylene fibers in improving the geo-environmental parameters as well as the durability of cement-based stabilized/solidified low plasticity clay containing different dosages of Pb. The leaching data revealed that while adding a low range (≤ 7.5%) of sole cement even in the severely polluted soils could fully eliminate the Pb bioavailability, the metal retention capacity might portray a marked sensitivity to the acid-washing process. A major reduction was also observed in the mechanical/leaching performance of those samples after undergoing the wetting-drying (w-d) cycle, especially at a high proportion of Pb, which could weaken the cementation bonding dramatically; hence, much more cement was needed to pass the required stabilization/solidification (S/S) standards. Besides, the micro level tests indicated that the application of SZ (with 25% cement replacement) would alleviate the Pb declining impact on the S/S reactions and modify the porous network of soil. As a result, the specimens amended by cement-SZ (CSZ) were more functional (~ 1.4 times) in immobilizing the toxic ions than the cement alone was. However, the CSZ admixture might not perfectly restrain the w-d forces/deteriorations. Such a potential drawback was found to be solvable by the insertion of fiber, in which case, an enhancement in the ductility and the metal capsulation could be also manifested. In fact, the CSZ/fiber treatment could form a well-intertwined matrix, showing high success rates in stabilizing/solidifying the contaminated soils alongside a significant decrease (~ 2-folds) in the quantity of needed amount of cement to give the S/S satisfactory operation under the harsh environmental conditions.

Combined effects of calcium-alginate coating and Artemisia fragrance essential oil on chicken breast meat quality.

The objective of the present study was to evaluate the effects of calcium-alginate (CA) containing Artemisia fragrance essential oils (AFEOs) as a potential antioxidant and antimicrobial coating on quality attributes and shelf life of chicken meat throughout keeping period (4°C). Five treatments were produced as follows: T1 (distilled water as control), T2 (2% CA), T3 (2% CA +500 ppm AFEOs), T4 (2% CA +1000 ppm AFEOs), and T5 (2% CA +1500 ppm AFEOs). The chicken meats packaged in polyethylene bags at atmospheric condition and physicochemical, microbiological, and organoleptic properties were assessed at days 1, 4, 8, and 12. There was no remarkable difference in proximate composition (moisture, ash, protein, and fat) of meat samples by treating with CA or AFEOs. The results revealed that CA +AFEOs coating reduced significantly the pH, total volatile base nitrogen (TVB-N), and thiobarbituric acid reactive substances (TBARS) values and also displayed higher contents of the total phenolic content (TPC) and redness value when compared with control. According to results, 2% CA +1500 ppm AFEOs reduced 58.3 (mg MDA (malondialdehyde)/kg) and 0.63 (mg/100 g) of TBARS and TVB-N values when compared to control, respectively. The microbiological count showed that CA +AFEOs had a significantly higher inhibitory impact on the total viable count (TVC), coliforms, molds and yeasts. At day 12, 6.89 Log CFU (colony-forming units)/g was recorded for TVC in 2% CA +1500 ppm AFEOs, which was the lowest overall. This treatment also displayed the reduction of 2.97 Log CFU/g in coliforms and 3.3 Log CFU/g in molds and yeasts in comparison with uncoated samples. The outcomes of pH, TBARS, TPC, color values, microbiological count, and organoleptic properties suggested 2% CA +1500 ppm AFEOs as an efficient coating for quality stability and improving the shelf life of chicken breast meat without negative impact on organoleptic properties.

Internal Acoustic Canal Stenosis Due to Hyperostosis.

Background Exostoses and osteomas are benign, insidious lesions of the bone involving the internal acoustic canal (IAC). We present two cases of IAC exostoses managed with surgical decompression and review the clinical outcomes of previously reported cases in the literature. Methods A comprehensive search was conducted using PubMed Central, Web of Science Core Collection, and Google Scholar databases to identify previous reports of IAC exostoses and osteomas. A total of 26 reported cases were identified, and patient presenting symptoms, management strategies, and response to surgery was obtained when available. Results Of the 13 patients who underwent surgical decompression, 8 patients had resolution of vertigo symptoms, 10 patients had improvement of tinnitus symptoms, and all patients maintained some level of serviceable hearing. Conclusion IAC exostoses and osteomas are rare lesions that lead to insidious onset of debilitating symptoms from vestibulocochlear nerve dysfunction. Although the role of surgical decompression remains unclear, it appears that patients presenting with vertigo have more favorable response to surgical decompression as compared with those presenting with tinnitus and sensorineural hearing loss.

Long-term impacts of road salt application on the groundwater contamination in urban environments.

This study explores the contamination potential of groundwater due to the use of sodium chloride (NaCl) in the wintertime. The research was conducted in two Iranian cities, Malayer and Hamedan, where groundwater is the major source of water for drinking and irrigating purposes. However, the amount of deicing salt used in the former is about 10 times less than that used in the latter. The assessment of geochemical dataset from 2004 to 2018 revealed no significant trend in the groundwater characteristics of Malayer where the water quality indices were in the range of WHO and USEPA permissible limits. In contrast, the indices had a continually increasing trend (~ 2.3% annually) in Hamedan's supply wells over the same period and particularly near the urban areas that showed higher levels (> 5 times on average) than those observed in Malayer. This could mainly be ascribed to the influx of halite. Based on the USSL diagram, the water samples retrieved from the latter system were mostly classified as C3-S1 (decreasing the soil fertility) and even as C4-S2 (harmful for agriculture activities). Chloride contamination rates also reached 250 mg/L, which could negatively affect the water potability and threaten the aquatics microorganisms. In this region, a rather similar distribution of NaCl and arsenic was observed, implying mobilization of toxic trace metals with the increased salt encroachment into the aquifer. Based on such findings, it is suggested that in snow-influenced cities (e.g., Hamedan), new approaches for winter maintenance be considered to prevent the gradual deterioration of water resources.

The Optimal Surgical Approach to Intradural Spinal Tumors: Laminectomy or Hemilaminectomy?

Objective Traditionally, laminectomy has been the preferred surgical approach for the resection of intradural spinal tumors. Recent trends towards minimally invasive techniques have generated interest in hemilaminectomy as an effective alternative surgical approach to resect spinal tumors. However, it remains unclear if the potential benefits of hemilaminectomies, used in other routine spinal procedures, apply to intradural spinal tumors. This report presents a six-year single institutional analysis of open resection of intradural tumors using laminectomies as compared to hemilaminectomies. Methods A single institution, multisurgeon, retrospective review of 52 patients undergoing resection of intradural spinal tumors over a six-year period was performed. Estimated blood loss, operative time, post-operative complications, length of stay, and post-operative clinical spinal instability were analyzed and compared between the two surgical techniques. Results The mean follow-up was 34 and 20 months for the laminectomy and hemilaminectomy groups, respectively. There was no statistically significant difference in operative times between the two groups (hemilaminectomy: 250.13±76.44 minutes, laminectomy: 244.49±92.85 minutes; p=0.43). Similarly, there was no difference in overall estimated blood loss (hemilaminectomy: 125±74 cc, laminectomy: 256.05±320.8 cc; p=0.27) or mean hospital length of stay (hemilaminectomy: 4.00±2.12 days, laminectomy: 5.26±3.0 days; p=0.60). No patient in either surgical group had post-operative evidence of clinical spinal instability. Conclusion Hemilaminectomy is a viable approach for the resection of intradural spinal tumors, with similar rates of post-operative complications to laminectomy when using an open surgical approach. The laminectomy allows for bilateral exposure of the entire spinal canal and neural foramina; and continues to be the preferred method for resection of large tumors with complex morphology.

The molecular oncology of bilateral high-grade thalamic astrocytomas in children.

BACKGROUND: Bilateral thalamic astrocytomas in children are exceedingly rare. These highly malignant tumors seldom respond to conventional treatment strategies and carry a grim prognosis for patients. However, recent advances in molecular oncology have had a positive impact on prognostication and treatment strategies of these tumors. CASE-BASED REVIEW: We present a new case of WHO grade III bilateral thalamic astrocytoma in a child and review the pathophysiology, molecular oncogenesis, and relevant treatment strategies for this rare disease. CONCLUSIONS: High-grade thalamic astrocytomas affecting both thalami pose a challenge to pediatric neurosurgeons, neuro-oncologists, and neuropathologists given the lack of effective treatment strategies. Understanding recent revelations in the field of molecular oncology can assist clinicians in adequately formulating a treatment plan in this patient population.

Measurement of eye and lens doses in the presence and absence of shield during whole brain irradiation.

AIM: The aim was to measure doses of eyes and lenses in the presence and absence of shield during whole brain irradiation (WBI). In addition, the dose calculations accuracy of radiation therapy dose plan treatment planning system (TPS) in dose calculation of the eyes and lenses in WBI was evaluated. MATERIALS AND METHODS: To measure the eyes and lenses doses during WBI, an inhomogeneous phantom of human head was used. Then, the eyes and lenses doses in the presence and absence of shield were measured by EBT3 film. RESULTS: In single fraction with 200 cGy to reference point, average doses received by the left and right eyes in the absence of shield were 20 ± 1.5 and 22 ± 1.0 cGy, respectively, and for the left and right eyes in the presence of shield were 18 ± 2.2 and 21 ± 2 cGy, respectively. In addition, the average dose received by the left and right lenses in the absence of shield were 19.5 ± 0.5 and 18.5 ± 0.5 cGy, respectively, and for the left and right lenses in the presence of shield were 20.5 ± 1.5 and 19.5 ± 1.5 cGy, respectively. The results showed the TPS compared to the film underestimates doses for the eyes and lenses. CONCLUSION: The average dose received by the eyes and lenses during WBI were estimated around 9-11% of prescribed dose. According to the results, there is probability of radiation-induced cataractogenesis during WBI. By investigating the effect of shield on the lenses and eyes doses, using shield during WBI is not recommended. In addition, the results showed dose calculation accuracy of the TPS for the estimation of doses received by the eyes and lenses during WBI is not acceptable.

Glioblastoma Multiforme of the Conus Medullaris-Management Strategies and Complications.

Primary spinal glioblastoma multiforme (GBM) of the conus medullaris is a rare and devastating pathologic entity. The presenting symptoms commonly include progressive neurologic deficits in the lower extremities, bowel and bladder dysfunction, and low back pain. Histologically, these tumors have high-grade features similar to their intracranial counterparts. However, recent advancements in the field of molecular oncology have been beginning to elucidate a unique molecular blueprint for these spinal gliomas. Given the lack of standardized treatment strategies, we have presented our institutional experience in treating a small series of patients with conus medullaris GBM and have reviewed the reported data on the relevant molecular markers, management strategies, and complication avoidance for this malignant pathologic entity.

A Multilayered Technique for Repair of the Suboccipital Retrosigmoid Craniotomy.

Objective Our primary objective was to retrospectively review our single institution experience using an anatomic multilayered repair of the retrosigmoid suboccipital craniotomy. Our secondary objective was to review the existing body of literature on the repair of this craniotomy and compare our outcomes to previous results. Design Retrospective review of 25 consecutive patients undergoing repair for the retrosigmoid craniotomy. Setting University of California Davis Medical Center (2010-2016). Participants A total of 25 consecutive patients who underwent retrosigmoid craniotomy and repair. Exclusion criteria included patients who were under the age of 18 years. Main Outcome Measures Main outcomes included incidence of postoperative headache, cerebrospinal fluid leak, and wound infections. Results Postoperative headache was reported in two patients in this series (8%). None of the patients in the series developed cerebrospinal fluid leak or wound infections. Mean follow-up period was 16 months. Conclusion Our multilayered anatomic repair after retrosigmoid suboccipital craniotomy results in favorable clinical results and may help reduce the risks associated with this operation.

Review of the Neural Oscillations Underlying Meditation.

Objective: Meditation is one type of mental training that has been shown to produce many cognitive benefits. Meditation practice is associated with improvement in concentration and reduction of stress, depression, and anxiety symptoms. Furthermore, different forms of meditation training are now being used as interventions for a variety of psychological and somatic illnesses. These benefits are thought to occur as a result of neurophysiologic changes. The most commonly studied specific meditation practices are focused attention (FA), open-monitoring (OM), as well as transcendental meditation (TM), and loving-kindness (LK) meditation. In this review, we compare the neural oscillatory patterns during these forms of meditation. Method: We performed a systematic review of neural oscillations during FA, OM, TM, and LK meditation practices, comparing meditators to meditation-naïve adults. Results: FA, OM, TM, and LK meditation are associated with global increases in oscillatory activity in meditators compared to meditation-naïve adults, with larger changes occurring as the length of meditation training increases. While FA and OM are related to increases in anterior theta activity, only FA is associated with changes in posterior theta oscillations. Alpha activity increases in posterior brain regions during both FA and OM. In anterior regions, FA shows a bilateral increase in alpha power, while OM shows a decrease only in left-sided power. Gamma activity in these meditation practices is similar in frontal regions, but increases are variable in parietal and occipital regions. Conclusions: The current literature suggests distinct differences in neural oscillatory activity among FA, OM, TM, and LK meditation practices. Further characterizing these oscillatory changes may better elucidate the cognitive and therapeutic effects of specific meditation practices, and potentially lead to the development of novel neuromodulation targets to take advantage of their benefits.

Toward a Neuroscience of Adult Cognitive Developmental Theory.

Piaget's genetic epistemology has provided the constructivist approach upon which child developmental theories were founded, in that infants are thought to progress through distinct cognitive stages until they reach maturity in their early 20's. However, it is now well established that cognition continues to develop after early adulthood, and several "neo-Piagetian" theories have emerged in an attempt to better characterize adult cognitive development. For example, Kegan's Constructive Developmental Theory (CDT) argues that the thought processes used by adults to construct their reality change over time, and reaching higher stages of cognitive development entails becoming objectively aware of emotions and beliefs that were previously in the realm of the subconscious. In recent years, neuroscience has shown a growing interest in the biological substrates and neural mechanisms encompassing adult cognitive development, because psychological and psychiatric disorders can arise from deficiencies therein. In this article, we will use Kegan's CDT as a framework to discuss adult cognitive development in relation to closely correlated existing constructs underlying social processing, such as the perception of self and others. We will review the functional imaging and electrophysiologic evidence behind two key concepts relating to these posited developmental changes. These include self-related processing, a field that distinguishes between having conscious experiences ("being a self") and being aware of oneself having conscious experiences ("being aware of being a self"); and theory of mind, which is the objective awareness of possessing mental states such as beliefs and desires (i.e., having a "mind") and the understanding that others possess mental states that can be different from one's own. We shall see that cortical midline structures, including the medial prefrontal cortex and cingulate gyrus, as well as the temporal lobe, are associated with psychological tasks that test these models. In addition, we will review computational modeling approaches to cognitive development, and show how mathematical modeling can provide insights into how sometimes continuous changes in the neural processing substrate can give rise to relatively discrete developmental stages. Because deficiencies in adult cognitive development can result in disorders such as autism and depression, bridging the gaps between developmental psychology, neuroscience, and modeling has potential implications for clinical practice. As neuromodulation techniques such as deep brain and transcranial stimulation continue to advance, interfacing with these systems may lead to the emergence of novel investigational methods and therapeutic strategies in adults suffering from developmental disorders.

Cervical spine fractures in osteopetrosis: a case report and review of the literature.

While management of appendicular fractures has been well described in the setting of osteopetrosis, there is limited information on managing fractures of the axial spine. Here we present an osteopetrotic patient with multiple traumatic multiple, comminuted, unstable cervical spinal fractures managed with non-operative stabilization, and provide a review of the pathophysiology, genetic characteristics, and special considerations that must be explored when determining operative versus non-operative management of spinal injury in osteopetrosis. A PubMed query was performed for English articles in the literature published up to June 2016, and used the following search terms alone and in combination: "osteopetrosis", "spine", "fractures", "osteoclasts", and "operative management". Within four months after initial injury, treatment with halo vest allowed for adequate healing. The patient was asymptomatic with cervical spine dynamic radiographs confirming stability at four months. On four-year follow up examination, the patient remained without neck pain, and CT scan demonstrated partially sclerotic fracture lines with appropriate anatomical alignment. In conclusion, external halo stabilization may be an effective option for treatment of multiple unstable acute traumatic cervical spine fractures in patients with osteopetrosis. Given the challenge of surgical stabilization in osteopetrosis, further research is necessary to elucidate the optimal form of treatment in this select patient population.

Mycobacterium Genavense Granuloma Mimicking a Brain Tumor: A Case Report.

Mycobacterium genavense (M. genavense) is a rare, non-tuberculous organism that commonly leads to gastrointestinal infections in immunocompromised patients. Only two cases of intracranial M. genavense infection have been reported to date. We describe a third case of M. genavense granuloma mimicking a right parietal intracranial mass, and review the literature on this exceedingly rare pathology.

Intradural Chordoma of Cerebellopontine Angle: Case Report and Review.

BACKGROUND: Chordomas are rare, notochord-derived neoplasms. Of these tumors, intradural chordomas are exceedingly rare. Most occur within the prepontine, parasellar, or other midline intradural locations. An intradural chordoma arising from the cerebellopontine angle has not been described previously. CASE REPORT: We describe the first case of an intradural chordoma originating from the left cerebellopontine angle resected over the course of 2 operations. CONCLUSIONS: Intradural chordomas are rare and can arise anywhere in the posterior fossa. Lack of bony involvement on computed tomography and magnetic resonance imaging are indicative of this pathology when there is also a lack of markers indicating the presence of more common cerebellopontine angle tumors. Treatment goals should include gross total resection and possible radiation therapy.

Effect of Stereoscopic Anaglyphic 3-Dimensional Video Didactics on Learning Neuroanatomy.

BACKGROUND: The teaching of neuroanatomy in medical education has historically been based on didactic instruction, cadaveric dissections, and intraoperative experience for students. Multiple novel 3-dimensional (3D) modalities have recently emerged. Among these, stereoscopic anaglyphic video is easily accessible and affordable, however, its effects have not yet formally been investigated. OBJECTIVE: This study aimed to investigate if 3D stereoscopic anaglyphic video instruction in neuroanatomy could improve learning for content-naive students, as compared with 2-dimensional (2D) video instruction. METHODS: A single-site controlled prospective case control study was conducted at the School of Education. Content knowledge was assessed at baseline, followed by the presentation of an instructional neuroanatomy video. Participants viewed the video in either 2D or 3D format and then completed a written test of skull base neuroanatomy. Pretest and post-test performances were analyzed with independent Student's t-tests and analysis of covariance. RESULTS: Our study was completed by 249 subjects. At baseline, the 2D (n = 124, F = 97) and 3D groups (n = 125, F = 96) were similar, although the 3D group was older by 1.7 years (P = 0.0355) and the curricula of participating classes differed (P < 0.0001). Average scores for the 3D group were higher for both pretest (2D, M = 19.9%, standard deviation [SD] = 12.5% vs. 3D, M = 23.9%, SD = 14.9%, P = 0.0234) and post-test performances (2D, M = 68.5%, SD = 18.6% vs. 3D, M = 77.3%, SD = 18.8%, P = 0.003), but the magnitude of improvement across groups did not reach statistical significance (2D, M = 48.7%, SD = 21.3%, vs. 3D, M = 53.5%, SD = 22.7%, P = 0.0855). CONCLUSION: Incorporation of 3D video instruction into curricula without careful integration is insufficient to promote learning over 2D video.

Intracerebroventricular opiate infusion for refractory head and facial pain.

AIM: To study the risks and benefits of intracerebroventricular (ICV) opiate pumps for the management of benign head and face pain. METHODS: SSix patients with refractory trigeminal neuralgia and/or cluster headaches were evaluated for implantation of an ICV opiate infusion pump using either ICV injections through an Ommaya reservoir or external ventricular drain. Four patients received morphine ICV pumps and two patientS received a hydromorphone pump. Of the Four patients with morphine ICV pumps, one patient had the medication changed to hydromorphone. Preoperative and post-operative visual analog scores (VAS) were obtained. Patients were evaluated post-operatively for a minimum of 3 mo and the pump dosage was adjusted at each outpatient clinic visit according to the patient's pain level. RESULTS: All 6 patients had an intracerebroventricular opiate injection trial period, using either an Ommaya reservoir or an external ventricular drain. There was an average VAS improvement of 75.8%. During the trial period, no complications were observed. Pump implantation was performed an average of 3.7 wk (range 1-7) after the trial injections. After implantation, an average of 20.7 ± 8.3 dose adjustments were made over 3-56 mo after surgery to achieve maximal pain relief. At the most recent follow-up (26.2 mo, range 3-56), VAS scores significantly improved from an average of 7.8 ± 0.5 (range 6-10) to 2.8 ± 0.7 (range 0-5) at the final dose (mean improvement 5.0 ± 1.0, P < 0.001). All patients required a stepwise increase in opiate infusion rates to achieve maximal benefit. The most common complications were nausea and drowsiness, both of which resolved with pump adjustments. On average, infusion pumps were replaced every 4-5 years. CONCLUSION: These results suggest that ICV delivery of opiates may potentially be a viable treatment option for patients with intractable pain from trigeminal neuralgia or cluster headache.

Clinical efficacy of stem cell mediated osteogenesis and bioceramics for bone tissue engineering.

Lower back pain is a common disorder that often requires bony spinal fusion for long-term relief. Current arthrodesis procedures use bone grafts from autogenous bone, allogenic backed bone or synthetic materials. Autogenous bone grafts can result in donor site morbidity and pain at the donor site, while allogenic backed bone and synthetic materials have variable effectiveness. Given these limitations, researchers have focused on new treatments that will allow for safe and successful bone repair and regeneration. Mesenchymal stem cells (MSCs) have received attention for their ability to differentiate into osteoblasts, cells that synthesize the extracellular matrix and regulate matrix mineralization. Successful bone regeneration requires three elements: MSCs that serve as osteoblastic progenitors, osteoinductive growth factors and their pathways that promote development and differentiation of the cells as well as an osteoconductive scaffold that allows for the formation of a vascular network. Future treatments should strive to combine mesenchymal stem cells, cell-seeded scaffolds and gene therapy to optimize the efficiency and safety of tissue repair and bone regeneration.