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.