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Evolution of sinkholes over Wink, Texas, observed by high-resolution optical and SAR imagery
摘要： Two caprock and cover collapse sinkholes, Wink Sinks #1 and #2, in Winkler County, Texas, collapsed in 1980 and 2002, respectively. They are located in a region underlain by the Salado Formation on the eastern edge of the Delaware Basin. The sinkhole collapses were associated with intense hydrocarbon drilling and production activities in the Hendrick oilfield. Production records and prior investigations imply the sinkholes developed after salt dissolution due to freshwater intrusion, cavity formation, roof failure, and successive upward cavity migration. High-resolution (1 m) aerial photography shows the ensuing expansion of Wink Sink #2 from 2002 through 2010 and relative stability of the ground surface after 2010. Very high-resolution (25 cm) staring spotlight mode TerraSAR-X reveals the spatiotemporal details of Wink sinkhole deformations. The vicinities around the two existing sinkholes (Wink Sinks #1, #2) deformed at a rate of 5 cm/yr in line-of-sight (LOS) direction from October 2015 to March 2016, and the deformation was possibly caused by the gradual deposit of the debris from overlying unconsolidated Alluvium and Santa Rosa sandstones infilling the cavity after the sinkhole collapse. Specifically, the largest deformation of 53 cm/yr in LOS direction was found 1 km east of Wink Sink #2. Our study suggests that severe drought in 2011 widened and created fractures as well as ground fissures in the rocks overlying and underlying the salt formation due to the increased effective stress. Fractures, ground fissures, and the abandoned unplugged boreholes or improperly completed wells opened one or more vertical pathways of freshwater from groundwater flow and precipitation toward the salt bed, finally causing the rapid salt dissolution and the opening of new cavities. To explain the onset of a rapid subsidence near the Wink sinkholes, our study considers the combined effect of natural perturbation (i.e., drought, rock fractures, ground fissures, subsurface drainage, precipitation) and anthropogenic effects (i.e., improper well control). Our method to explore high-resolution imagery can be applied to characterize the sinkhole deformation and mitigate sinkhole-related geohazards.
关键词： Fractures,High-resolution InSAR,Aerial photography,Wink sinkholes,Ground fissures,Rapid subsidence
更新于2025-09-23 15:23:52
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A method of percutaneous vertebroplasty under the guidance of two C-arm fluoroscopes
摘要： Objective: To compare the clinical application in the percutaneous vertebroplasty under the guidance of one or two C-arm fluoroscopes. Methods: One hundred forty three elderly patients with Osteoporotic vertebral compression fractures (OVCFs) underwent percutaneous vertebroplasty under the guidance of one or two C-arm fluoroscopes. The number of pulsed imagings, the time of operation and the incidence of cement leakage were recorded. Results: The average number of pulsed imagings was 16.00±1.58 vs 13.07±2.00 per patient under the guidance of one vs two C-arm fluoroscopes. The average time of operation was 48.42±5.00 minutes vs 39.70±7.42 minutes per patient under the guidance of one vs two C-arm fluoroscopes. The incidence of cement leakage was 20% vs 15.7% of the patients under the guidance of one vs two C-arm fluoroscopes. The differences in the number of pulsed imagings and the time of operation were statistically significant. The difference in incidence of cement leakage was not statistically significant. Conclusion: The two-fluoroscopic technique reduce the labor cost, the radiation, the time of operation and the operation risk.
关键词： Percutaneous vertebroplasty,Two C-arm fluoroscopes,Osteoporotic vertebral compression fractures
更新于2025-09-23 15:22:29
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Effective management of bone fractures with the IlluminOss? photodynamic bone stabilization system: initial clinical experience from the European Union registry
摘要： The IlluminOss? system (IS) uses a light-curable polymer contained within an inflatable balloon catheter, forming a patient customized intramedullary implant. A registry was established in Germany and The Netherlands to prospectively collect technical and clinical outcomes in patients treated with IS for fractures of the phalange, metacarpal, radius, ulna, distal radius, fibula, clavicle and/or olecranon. Humeral, femoral, tibial and pelvic fractures were included. Procedural success included successful placement of the device at the target fracture site and achievement of fracture stabilization. Clinical and radiographic assessments were made postoperatively through 12 months. One hundred thirty two patients (149 fractures) were enrolled with most fractures (85%) resulting from low-energy trauma. Simple fractures predominated (47%) followed by complex (23%) and wedge (16%) fractures. Procedural success was achieved in all patients and no implants required removal or revision. Normal range of motion was realized in 87% of fractures. Radiographically, there was substantial cortical bridging, total dissolution of the fracture line, and complete fracture healing. Across a variety of fracture types, the IS provides a safe and effective approach for rapid healing and functional recovery.
关键词： Long bone,Fractures,Minimally-invasive,Appendicular,Photodynamic
更新于2025-09-23 15:22:29
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Application of Laser Phoresis in Complicated Postmenopausal Osteoporosis
摘要： This study presents postmenopausal osteoporosis as a feature of metabolic systemic diseases of the skeleton, with abnormalities of the bone microarchitecture and reduction in bone mineral density, leading to an increased risk of fractures with a low level of trauma. The neurological manifestations of such fractures are uncharacteristic, representing a differential diagnostic indication. There is a change of posture in the form of hyperkyphosis of the thoracic spine and loss of height due to the increase in the number of modified vertebrae. The age of these patients is between 66 and 68 years, which limits the use of traditional analgesic preparations. The ionized gel ‘Giasulf’ was applied in 29 cases according to the developed technology. The description of the composition of the gel that provides maximum analgesic effect, reinforced by the influence of laser radiation on the cell membranes, is presented. A significant antinociceptive effect was obtained.
关键词： Analgesia,Osteoporotic fractures,Laser phoresis,Giasulf,Osteoporosis
更新于2025-09-16 10:30:52
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Radiation exposure during direct versus indirect image acquisition during fluoroscopy-controlled internal fixation of a hip fracture: Results of a randomized controlled trial
摘要： Background: Intra-operative image acquisition can be obtained indirectly (via verbal request to a technician) or directly (executed at the tableside, by a surgeon stepping on a foot pedal). Direct image acquisition could reduce the exposure time and thus the risk of radiation damage. The aim of this randomized controlled trial was to compare direct surgeon-controlled fluoroscopy with indirect technician-operated fluoroscopy during internal fixation of a hip fracture. Methods: From March 5, 2014 to August 19, 2015, 100 patients who had sustained a hip fracture that required internal fixation were enrolled. Patients were randomized between direct surgeon-controlled image acquisition using a foot pedal (n = 52) and indirect image acquisition by a radiology technician (n = 48). The primary outcome measure was the radiation exposure time; secondary outcome measures were the associated effective radiation dose and the dose area product. (DAP) Results: A total of 96 patients (with a median age of 84 years) were enrolled in this study. Eighty-nine (93%) patients had a pertrochanteric fracture. No statistically significant differences between direct image acquisition and indirect image acquisition were found for overall radiation time, total radiation dose or DAP for the total population. When adjusted for potential confounders, a difference in overall radiation time of 18.50 s (95% CI 2.19; 34.81, p = 0.027) was found in favour of indirect image acquisition. Conclusion: This study showed statistically significantly lower radiation duration using indirect fluoroscopy for the total population and the pertrochanteric fracture subgroup when adjusted for several confounders. No significant effect on radiation dose and DAP was found.
关键词： Radiation dosage,Radiation protection,Hip fractures,Fluoroscopy,Femoral fractures
更新于2025-09-11 14:15:04
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Structural mapping of rock walls imaged with a LiDAR mounted on an unmanned aircraft system
摘要： Structural mapping of rock walls to determine fracture orientation provides critical geological information in support of mining operations. A helicopter-style UAS (rotor diameter 2 m; take-off mass 35 kg; payload mass 11 kg) instrumented with a high-resolution LiDAR imaged a 75 m long and 10-15 m high series of 4 adjacent rock walls at the Canadian Wollastonite mine. A point cloud with a density of 484 point/m2 acquired at an angle of incidence of ~41.7° from a flight altitude of 41.7 m above ground level was selected for structural mapping. The point cloud was first meshed using the Poisson surface reconstruction method, and then remeshed to achieve an even element size distribution. Visualization of the remeshed Poisson mesh using a 360° hue-saturation-lightness colour wheel highlighted areas of higher fracture density, whereas visualization using a 180° colour wheel accentuated sliver-like geological features. Two joint sets were identified at 156/82 and 241/86 (strike/dip in degrees). A total of 18 virtual strike measurements and 13 virtual dip measurements were within 10% of manual compass measurements. This study demonstrated that the task of structural mapping of large rock walls can be automated by processing 3D images acquired with a LiDAR mounted on a UAS.
关键词： rock fractures,open pit mining,airborne LiDAR,unmanned helicopter,3D imaging
更新于2025-09-09 09:28:46