Circumferential Pannus at C1-C2 Causing Spinal Cord Compression.

Periodontoid pannus formation is a pathologic condition caused by a multitude of different etiologies, however, it is most commonly due to rheumatoid arthritis. In these cases, the pannus is typically located in the retro-odontoid space ventral to the spinal cord, leading to progressive neural compression. We describe in this report, a patient who presented with progressive high cervical myelopathy, who on imaging revealed both a retro-odontoid pannus and a posterior C1-C2 mass causing severe circumferential compression of the spinal cord. The patient was successfully treated with a C1-C2 laminectomy and occipitocervical fusion. Periodontoid pannus is a common entity; however, the presence of a C1-C2 posterior pannus is a unique finding. To our knowledge, circumferential pannus at C1-C2 causing neural compression is a clinical entity that has not been previously reported.

Autologous Cranioplasty with Bone Flap Preserved in Conventional Freezers: An Adequate Option in Low Resource Settings.

BACKGROUND: Autologous cranioplasty has been used for decades and is the gold standard treatment in patients who underwent decompressive craniectomy (DC). One of the most common methods to store the cranial bone flap is cryopreservation at very low temperatures (-70 to -80°). The only way to achieve these low temperatures is by using special freezers which are not always available in all medical facilities, especially in low-resource centers. This paper describes our experience with the storage of cranial bone flaps in freezers of conventional refrigerators. METHODS: This retrospective study included patients treated with autologous cranioplasty, operated between 2015 and 2020. The cranial bone flap was stored at -18°C in the freezer of conventional refrigerators. Complications and outcomes were analyzed and compared with reports of patients in whom ultra-low temperature freezers were used for bone flap preservation. RESULTS: Twenty-five patients were included. The average follow-up period was 33 months. Trauma was the most common cause of DC, followed by stroke. The mean age was 36.7. Aseptic bone flap resorption was observed in 4 cases (16%). No cases of infection were observed. CONCLUSIONS: The use of freezers from conventional refrigerators may be an acceptable alternative for the preservation of the cranial bone flap in facilities where special freezers are not available. The rate of aseptic bone necrosis and infections observed in this paper was similar to the incidence of these complications reported in studies where ultra-low temperatures were used.

Robotic-assisted single-position lateral for multilevel circumferential lumbar interbody fusion: how I do it.

BACKGROUND: Lateral lumbar interbody fusion supplemented with insertion of pedicle screws is a surgical procedure that has gained popularity in the last years, becoming an important tool in the armamentarium of spine surgeons. In recent years, there is a trend to complete both procedures in a single position, thus avoiding flipping the patient prone to insert the pedicle screws. METHODS: We describe a step-by-step workflow of the robotic-assisted technique for multilevel lateral lumbar interbody fusion supplemented with posterior instrumentation. The surgical procedure is performed in a single lateral position. For access to L4-5 or L5-S1, an oblique abdominal incision is performed in the same position, and the desired disc space is approached through an oblique or anterior corridor in the retroperitoneal space. CONCLUSION: Robotic-assisted single-position lateral for multilevel circumferential lumbar interbody fusion is a safe and effective procedure in patients where lumbar stabilization is required. This technique provides patients with a faster recovery and low risk of complications.

Seizure-Induced Spinal Fractures: A Systematic Review.

BACKGROUND: Patients with epilepsy have a higher risk of skeletal injuries, and some of these fractures occur in the spine during a seizure. Seizure-induced spinal fractures (SISF) are unusual injuries that typically occur in the thoracolumbar spine. Because these skeletal injuries are not well described in the literature, this article aims to analyze the characteristics of this uncommon clinical entity. METHODS: A PubMed and Scopus search adhering to preferred reporting items for systematic reviews and meta-analyses guidelines was performed to include studies reporting patients with SISF. The data gathered from this review were analyzed to characterize this condition. RESULTS: The search yielded 34 articles with a total of 38 patients with SISF. All studies were case reports (level 5 evidence). Most fractures occurred in the thoracic and lumbar spine, and the most common injuries were type A1 and A4 fractures according to the AO spine classification system. Different characteristics of SISF are described including demographics, clinical findings, imaging, and treatment. CONCLUSIONS: SISF should be ruled out in patients who have a recent history of seizures and who report persistent dorsolumbar pain or neurological deficit. SISF usually occurs in the thoracolumbar spine and less frequently in the cervical spine. This review shows that different patterns of neurological deficits, some of them severe, may occur in approximately a quarter of patients with SISF. CLINICAL RELEVANCE: This study provides awareness of an uncommon spine condition. Physicians should suspect SISF in patients with persistent dorsolumbar pain after a seizure.

An environmental assessment for municipal organic waste and sludge treated by hydrothermal carbonization.

Climate change is the world's greatest challenge today, the reason why it is urgent to optimize industrial processes and find new renewable energy sources. Hydrothermal carbonization (HTC) is one of the Waste-to-Energy technologies with greater projections due to its operative advantages. However, for its large-scale implementation, there are challenges related to the variability of the composition of the waste biomass and the seasonal and geographical availability. This research applied the Life Cycle Analysis methodology to evaluate the environmental impacts caused by three biomasses blends as raw material in the HTC process at laboratory scale. The blends analyzed considered different organic fractions of municipal solid waste (food and pruning) and sewage sludge. The results showed that blend 1 had a lower environmental impact for the case of production in the experimental laboratory level, compared with blends 2 and 3. This is mainly due to its greater calorific value and mass yield, which allows obtaining more hydrochar compared with the other blends, increasing the energy efficiency of the process. Also, between 87.94% and 98.00% of the energy reduction is required to obtain neutral impacts regarding the energy requirements in the experimental laboratory level scenario and the Chilean energy matrix. The processing of blends in HTC has excellent potential in a context where municipal solid wastes have been disposed in sanitary landfills or dumps, as in most emerging countries. Since this study incorporated data from the literature, future studies should perform an elemental analysis to provide experimental and differentiated data.

Hypertensive primary intraventricular hemorrhage: a systematic review.

Primary intraventricular hemorrhage (PIVH) is a special subtype of intraventricular hemorrhage (IVH) without a hemorrhagic parenchymal component. Different conditions may cause this uncommon hemorrhage including trauma, vascular anomalies, coagulation disorders, and others. Frequently, PIVH is associated with structural vascular anomalies such as aneurysms, arteriovenous malformations, and dural fistulas. Traditionally, hypertension has been considered a predisposing factor for PIVH. A wide variety of studies have been published describing patients with PIVH; however, studies describing exclusively patients with hypertensive PIVH are lacking in the literature. For this reason, the features of PIVH secondary to hypertension are not well described. The purpose of this study is to analyze and describe the characteristics of hypertensive PIVH. A PubMed and Scopus search adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed to include studies reporting patients with hypertensive PIVH. The search yielded 19 articles reporting retrospective case series. The diagnosis of hypertensive PIVH should be established in patients meeting the following criteria: (a) elevation of blood pressure is observed at admission, (b) a cerebral angiography is negative for vascular anomalies, and (c) other causes of intracranial hemorrhage are ruled out. The prognosis is poorer in patients who present with low Glasgow Coma Score (GCS), old age, hydrocephalus, or more extensive intraventricular bleeding. The results of this study show that hypertension is the most common cause of PIVH, followed by hemorrhage caused by vascular anomalies. Hypertension may be a direct cause of PIVH, but also it may be a predisposing factor for bleeding in cases of an associated vascular anomaly.

Orbito-cranial gunshot injury: the case of the missing entrance wound.

This paper presents the case of a 68 years old male who was admitted to the hospital after being attacked by another person. The main clinical signs were confusion and severe periorbital edema, findings of gunshot injury were not evident initially. However, a CT scan showed findings compatible with an orbito-cranial perforating gunshot injury. To the best of the author's knowledge, cases like this have not been reported in the literature. This report shows us that an orbito-cranial gunshot injury should be ruled out in cases of severe periorbital edema, especially if the cause of the injury remains unidentified.

Valorization of oat husk by hydrothermal carbonization: Optimization of process parameters and anaerobic digestion of spent liquors.

The hydrothermal carbonization (HTC) optimization of oat husk was performed using a response surface methodology. Furthermore, anaerobic digestion (AD) of spent liquor and hydrochar addition were evaluated in the biomethane potential (BMP) test. Results found that temperature influences the most in the studied responses (i.e., mass yield (MY) and higher heating value (HHV)). Optimal hydrochar MY (53.8%) and HHV (21.5 MJ/kg) were obtained for 219.2 °C, 30 min, and 0.08 of biomass/water ratio. A successful prediction capability of the optimization approach was observed, archiving an error < 1% between predicted and validated responses. The BMP experiment showed the feasibility of spent liquor as a potential substrate to be treated by AD (144 NmLCH4/gCOD). Hydrochar boosted the methane production of spent liquor increasing up to 17% compared to digestion with no hydrochar addition. These findings provide new insights regarding oat husk valorization by integrating HTC and AD for energy production.

The black carbon dispersion in the Southern Hemisphere and its transport and fate to Antarctica, an Anthropocene evidence for climate change policies.

Black carbon (BC) has been measured in Antarctica's air, and its global warming effect can potentially speed up the ice melting in the most solid water reservoir of the planet. However, the primary responsible sources are not well evidenced in this region. The dispersion of black carbon emissions from the Southern Hemisphere was conducting using atmospheric chemical transport model and we compared the results with satellite registries from March 1st to April 30th in 2014. The emission inventory considered the anthropogenic and biomass burning emissions from global datasets. The largest and most populated cities in Southern Hemisphere showed the higher emission of BC. As a result, the average daily concentrations of atmospheric BC were around 4 ng/m3 in most regions of Antarctica according to its pristine characteristics. We analyzed fifteen relevant sites in coastal zones of Antartica and some peaks registered by the satellite records were not replicated by model outputs and it was mainly associated with the lack of emissions. Finally, we made simulations in the same period without biomass burning emissions and we observed decreased concentrations of BC in the range of 20-50%. As a result, we show that the black carbon transportation from the continental land to the polar region took place in 17-24 days during the Austral summer and the biomass burning emissions were the primary source. Black Carbon deposition in Antarctica is not permanent, but the uncontrolled emissions from Southern Hemisphere can increase its transportation to the white continent and make its accumulation during the period when the weak polar vortex occurs.

Motor Neuron Disease in a Patient With Cervical Spondylotic Myelopathy: Too Much Bad Luck.

Cervical spondylotic myelopathy (CSM) and amyotrophic lateral sclerosis (ALS) share some clinical findings. Hence, motor neuron disease (MND) should be considered in the differential diagnosis of patients presenting with signs and symptoms of CSM. This unique case demonstrates the coexistence of both conditions in the same patient. The author reports the case of a 74-year-old male who initially underwent posterior cervical decompression and instrumented fusion for cervical myelopathy. He demonstrated postoperative improvement followed subsequently by unexplained neurological deterioration. A repeat MRI showed adequate decompression of the cervical cord and persistence of T2 hyperintense signal in the spinal cord. Based on the presence of signs and symptoms of lower motor neuron disease, electromyography (EMG) was performed demonstrating findings of MND. The presence of MND in a patient with CSM is unique and can be difficult to diagnose based on overlapping symptoms. This case highlights the importance of EMG and the vigilance that spine surgeons need to display to identify ALS or other MND, despite the presence of ongoing cervical myelopathy. In cases where patients show discordant symptoms, further studies should be performed.

Bilateral Large Vessel Occlusion Causing Massive Ischemic Stroke in a COVID-19 Patient.

The case of a 70-year-old male presenting an ischemic stroke related to COVID-19 infection is described. He was initially admitted to the hospital with respiratory insufficiency syndrome secondary to pneumonia caused by SARS Co2. In the next days, he developed rapid neurological deterioration characterized by drowsiness which progressed to deep coma. D-dimer was elevated. Brain CT scan showed bilateral massive ischemic stroke located in the anterior circulation, CT angiogram showed occlusion in the left internal carotid artery and the right middle cerebral artery. The deterioration of the patient continued and he subsequently died. Large vessel occlusion has been reported in COVID-19 patients, but this clinical presentation is usually unilateral. Cases of bilateral occlusion of large vessels have not been previously reported in COVID-19 patients. This report shows that bilateral massive stroke may occur in COVID-19 cases and it should be suspected in patients who show rapid neurological deterioration without focal deficits.

Chondromas of the Lumbar Spine: A Systematic Review.

STUDY DESIGN: Systematic review and illustrative case. OBJECTIVES: Lumbar spinal chondromas (LSCs) are rare spine tumors. The characteristics of these intraspinal lesions are not well described in the literature. The goal of this article is to describe the features of this rare spinal tumor. METHODS: A PubMed and Scopus search adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed to include studies reporting patients with LSCs. The data gathered from this review was analyzed to characterize LSCs. RESULTS: The search yielded 14 cases of patients with LSCs. All studies were case reports (Level V of evidence). Different characteristics of LSCs are described, including demographics, clinical findings, imaging, and treatment. CONCLUSIONS: The results of this review show that LSCs are almost exclusively seen in the extradural space and may adopt a dumbbell shape. LSCs frequently manifest in a very similar way to lumbar disc herniations; therefore, they should be considered in the differential diagnosis of sciatica, especially if magnetic resonance imaging with gadolinium shows peripheral rim enhancement of the lesion. Different degrees of improvement are usually observed after surgical treatment of these patients.

Black and organic carbon fractions in fine particulate matter by sectors in the South Hemisphere emissions for decision-making on climate change and health effects.

Some databases report global emissions of certain pollutants. Emissions Database for Global Atmospheric Research (EDGAR) project is one of these, which also records emissions by sources. In this study, the emissions of black and organic carbon and fine particulate matter from the EDGAR database were used as an input to process it in the Sparse Matrix Operator Kernel Emissions (SMOKE) model. We showed the spatial distribution of the fraction of black and organic carbon in particulate matter from each source in the Southern Hemisphere. Also, we extracted these ratios for several cities in the domain of analysis. The results and methodology of this study could improve the emission inventories with bottom-up methodology in areas without information located at Southern Hemisphere. Also, it could be relevant to obtain better performance in air quality modeling at the local level for decision-making on climate change and health effects.

Spontaneous Extrusion of Ventriculopleural Shunt Catheter Associated with Pleural Effusion.

BACKGROUND: Ventriculopleural (VPL) shunts are used infrequently in management of hydrocephalus. The main complication associated with these shunts is pleural effusion. CASE DESCRIPTION: A 28-year-old man with a history of congenital hydrocephalus had a VPL shunt inserted. Two years later, he noticed a soft bulging in the surgical scar area of the chest, suggestive of fluid accumulation. The scar subsequently opened up spontaneously exposing the distal catheter, which extruded through the opening. Chest radiographs and computed tomography scan showed an important pleural effusion on the same side. The VPL shunt was removed, and a contralateral shunt was inserted. CONCLUSIONS: To our knowledge, spontaneous extrusion of the distal catheter of a VPL shunt has not been previously reported in the literature. Physicians treating patients with hydrocephalus must be aware of this potential complication when a VPL shunt is inserted.

Sarcoidosis of the Skull: A Systematic Review.

BACKGROUND: Lesions of the skull make up a small but important part of neurosurgical practice. Several systemic disorders may involve the cranial vault including neoplastic and non-neoplastic conditions. Sarcoidosis of the skull is a little-known cause of calvarial involvement that has been rarely reported in the literature. The available information about skull sarcoidosis (SS) is sparse and is not well described; for this reason, we consider that a detailed description of this uncommon condition is necessary. METHODS: An illustrative case of SS is presented; in addition, a PubMed and Scopus search adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed to include studies reporting patients with SS. Different information was analyzed in these cases to describe the characteristics of this condition. Also, different sources of literature were analyzed to complete the description of this clinical entity. RESULTS: The search yielded 22 cases of patients with SS showing a variety of clinical manifestations. All studies were case reports. Most patients diagnosed with SS had no previous history of systemic sarcoidosis. Different characteristics of SS are analyzed and described in this paper. CONCLUSIONS: The information collected from this review shows that SS is a rare condition that frequently is observed in patients without previous diagnosis of sarcoidosis. SS may manifest in different ways, and even may be found incidentally in some patients. The diagnosis of SS should be considered when multiple lytic skull lesions are observed, especially in cases of patients without a previous history of malignancy.

Retro-Odontoid Pseudotumor without Radiologic Atlantoaxial Instability: A Systematic Review.

BACKGROUND: Retro-odontoid pseudotumor (RP) can be caused by several diseases, especially rheumatoid arthritis, and is usually associated with the presence of atlantoaxial instability. On the other hand, a different group of patients have been identified in whom RP is observed without radiologic findings of atlantoaxial instability. The pathophysiology, clinical characteristics, and prognosis of this latter group of patients are not well described in the literature. METHODS: A PubMed and Scopus search adhering to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines was performed to include studies reporting patients with RP without radiologic instability (RPWRI). The data gathered from this review were analyzed to characterize RPWRI. RESULTS: The search yielded 36 articles with a total of 62 patients. All studies were case reports and small case series. Different characteristics of RPWRI are described, including causes, pathophysiology, and treatment. CONCLUSIONS: The results of this review show that RPWRI has different causes such as hypermobility, deposition of substances, and perhaps disc herniation. Depending on the cause of RPWRI, the pathophysiologic mechanism is different. Treatment should be tailored based on the primary cause of RP and the degree of compression of the cervicomedullary junction. Different degrees of improvement are usually observed after surgical treatment in these patients regardless of the treatment used, but a higher rate of mass regression was observed in those patients in whom the atlantoaxial joint was stabilized.

Spine Injuries Related to Ocean Waves: Case Series of Unusual Injuries.

Spine injuries related to ocean wave accidents are little known because they exclusively occur in beach destinations. This unusual type of trauma happens when these patients are slammed or caught by a wave, rolled over, and driven into the water, usually hitting the head on the seabed. Due to the kinematics of ocean wave accidents, spine injuries occur almost exclusively in the subaxial cervical spine. Several cases of spine injuries associated with ocean wave accidents are described. These ocean bathers presented with spinal trauma in levels other than the subaxial cervical spine. Two patients presented with injuries in the upper cervical spine, another patient showed a thoracic fracture, and finally, another patient sustained a lumbar compression fracture. All patients were tourists with minimal experience with swimming in the ocean who very likely ignored the danger of waves. This study shows that spine injuries related to ocean waves can occur at any level of the spine. Therefore, emergency physicians and spine surgeons must be aware of unusual locations of this unique type of trauma.