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1.
Methods Mol Biol ; 2856: 63-70, 2025.
Artigo em Inglês | MEDLINE | ID: mdl-39283446

RESUMO

Three-dimensional (3D) chromosome structures are closely related to various chromosomal functions, and deep analysis of the structures is crucial for the elucidation of the functions. In recent years, chromosome conformation capture (3C) techniques combined with next-generation sequencing analysis have been developed to comprehensively reveal 3D chromosome structures. Micro-C is one such method that can detect the structures at nucleosome resolution. In this chapter, I provide a basic method for Micro-C analysis. I present and discuss a series of data analyses ranging from mapping to basic downstream analyses, including loop detection.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Software , Fluxo de Trabalho , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Cromossomos/genética , Biologia Computacional/métodos , Mapeamento Cromossômico/métodos , Nucleossomos/química , Nucleossomos/genética , Nucleossomos/metabolismo
2.
Notas enferm. (Córdoba) ; 25(43): 62-65, jun.2024.
Artigo em Espanhol | LILACS, BDENF, UNISALUD, InstitutionalDB, BINACIS | ID: biblio-1561284

RESUMO

El síndrome compartimental agudo requiere de la descompresión quirúrgica, mediante fasciotomía, esta técnica debe ser urgente y será clave para evitar la instauración de graves secuelas. El posterior abordaje de estas heridas de difícil y lenta cicatrización suponen un reto para los profesionales de la salud y un problema para la salud pública debido a los altos costes y elevada morbilidad. La terapia de presión negativa (TPN) o cura por vacío (VAC, "vacuum assisted closure") es un tratamiento no invasivo que consigue la curación de las heridas favoreciendo la vascularización, la aparición del tejido de granulación y eliminación del exceso de exudado[AU]


Acute compartment syndrome requires surgical decompression by fasciotomy, this technique must be urgent and will be key to avoid the establishment of serious sequels. The subsequent approach to these wounds, which are difficult and slow to heal, is a challenge for health professionals and a problem for public health due to high costs and high morbidity. Negative pressure therapy (NPWT) or vacuum assisted closure (VAC) is a non-invasive treatment that achieves wound healing by promoting vascularization, the appearance of granulation tissue and elimination of excess exudate[AU]


A síndrome compartimental aguda requer descompressão cirúrgica, por fasciotomia, esta técnica deve ser urgente e será fundamental para evitar o estabelecimento de sequelas graves. O tratamento subsequente destas feridas difíceis e de cicatrização lenta é um desafio para os profissionais de saúde e um problema desaúde pública devido aos elevados custos e à elevada morbilidade. A terapia por pressão negativa (NPWT) ou o encerramento assistido por vácuo (VAC) é um tratamento não invasivo que permite a cicatrização de feridas através da promoção da vascularização, do aparecimento de tecido de granulação e da remoção do excesso de exsudado[AU]


Assuntos
Humanos , Fasciotomia
3.
Int J Surg Case Rep ; 123: 110215, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39232349

RESUMO

INTRODUCTION: Traditional bone setting, a centuries-old practice, remains a common method for treating musculoskeletal injuries in many parts of the world, particularly in developing regions. In Indonesia, traditional bone-setters are widely sought after in managing various bone and joint conditions. Despite the widespread use of traditional bone settings, there is limited documentation of their treatment outcomes and potential complications. Complications such as a necrotic limb due to vascular interruption as shown in our case are common complications of fracture reduction by individuals who have not been formally trained. CASE REPORT: This case report presents a 4-year-old boy, who came in the emergency department with pain on the arm after falling from the stairs. After a thorough examination, it was concluded that this patient has a displaced right proximal humerus fracture. The patient and family are educated about the surgery to treat the patient, but they refuse to do so. Two days later, the patient was referred to our hospital with a complaint of a blackened upper arm after undergoing a traditional bone-setting procedure. The patient's condition was characterized by loss of motor and sensory function in the affected limb, which was confirmed through clinical examination and imaging studies. He underwent shoulder disarticulation by an orthopedic surgeon in our center. This was decided because the limb was non-functional, inconvenient, and is at risk of becoming a focus of infection. DISCUSSION: Dead limb caused by traditional bone setters is a major factor leading to amputations in numerous developing nations. Techniques such as scarification, massage with herbal preparations, and the application of tightly fitting splints can result in infections, vascular impairment, and compartment syndrome, ultimately culminating in gangrene or limb loss. This case highlights the progressive and potentially limb-threatening nature of such infections, underscoring the critical need for early identification of compartment syndrome, prompt resuscitation or stabilization efforts, and immediate, vigorous treatment. CONCLUSION: This case is reported to highlight the risks associated with traditional bone-setting practices and the inherent dangers they pose. Individuals misled by misconceptions should be educated through public awareness campaigns. Additionally, governmental legislation should be enacted to integrate traditional bone-setting practices with modern orthopedic care services.

4.
Int J Surg Case Rep ; 123: 110192, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39241478

RESUMO

INTRODUCTION: Colorectal cancer leads to peritoneal metastasis in 8-15 % of cases and necessitates treatments, such as hyperthermic intraperitoneal chemotherapy (HIPEC). However, HIPEC may result in perioperative complications, some often overlooked, such as abdominal compartment syndrome. CASE PRESENTATION: A 52-year-old female with colorectal cancer and peritoneal metastasis underwent debulking surgery followed by HIPEC. During HIPEC, a sudden increase in airway pressure and severe hypotension were noted. Pneumothorax with abdominal compartment syndrome (ACS) was suspected and HIPEC was terminated. Despite intravenous fluids and vasopressors, she experienced circulatory and respiratory collapse. Laparotomy sutures were promptly removed, which effectively alleviated the intra-abdominal hypertension and immediately restored the vital signs. An inadequately repaired diaphragm defect was identified and repaired. A chest tube was inserted for pleural effusion. DISCUSSION: ACS is characterized by an increase in abdominal cavity pressure above 20 mmHg, leading to end-organ damage. It can mimic physiological effects of HIPEC and result in adverse outcomes. Early detection of ACS is essential, especially when complicated by pneumothorax from diaphragmatic tumor dissection. The closed technique for HIPEC, while efficient, can increase the risk of ACS and requires careful management. CONCLUSIONS: This case underscores the complexity of HIPEC and the importance of promptly identifying and managing ACS during the procedure. Monitoring intra-abdominal pressure during HIPEC is essential. Thoroughly check for iatrogenic injuries, including the diaphragm, is crucial before starting before HIPEC.

5.
Magn Reson Med ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39323069

RESUMO

PURPOSE: To investigate microstructural alterations induced by perfusion fixation in brain tissues using advanced diffusion MRI techniques and estimate their potential impact on the application of ex vivo models to in vivo microstructure. METHODS: We used oscillating gradient spin echo (OGSE) and b-tensor encoding diffusion MRI to examine in vivo and ex vivo microstructural differences in the marmoset brain. OGSE was used to shorten effective diffusion times, whereas b-tensor encoding allowed for the differentiation of isotropic and anisotropic kurtosis. Additionally, we performed Monte Carlo simulations to estimate the potential microstructural changes in the tissues. RESULTS: We report large changes (˜50%-60%) in kurtosis frequency dispersion (OGSE) and in both anisotropic and isotropic kurtosis (b-tensor encoding) after perfusion fixation. Structural MRI showed an average volume reduction of about 10%. Monte Carlo simulations indicated that these alterations could likely be attributed to extracellular fluid loss possibly combined with axon beading and increased dot compartment signal fraction. Little evidence was observed for reductions in axonal caliber. CONCLUSION: Our findings shed light on advanced MRI parameter changes that are induced by perfusion fixation and potential microstructural sources for these changes. This work also suggests that caution should be exercised when applying ex vivo models to infer in vivo tissue microstructure, as significant differences may arise.

6.
Cureus ; 16(8): e67886, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39328622

RESUMO

Well-leg compartment syndrome is a rare and severe complication that occurs after prolonged surgery in the lithotomy position. This review outlines the presentation, diagnosis, and management of well-leg compartment syndrome after colorectal surgery. A comprehensive and systematic search of various electronic databases was conducted. All case reports and case series of well-leg compartment syndrome after colorectal surgery were included. Patient demographics, operative details, presenting symptoms, investigations, management, and treatment outcomes were collected from the eligible reports. Twenty-three articles, reporting a total of 36 patients, were eligible for inclusion in this review. Most of the included patients were male (88.9%), with an age range of 7-74 years. All reported cases in this review were placed in lithotomy position variations (standard lithotomy, Lloyd-Davies, and modified lithotomy) with an operative time exceeding four hours. Moreover, the presenting symptoms were lower limb pain, swelling, and loss of sensation on postoperative days 0 and 1. Fasciotomy was performed in 88.9% of cases, and half of the patients developed permanent sensory or motor dysfunction in the lower limbs. In conclusion, well-leg compartment syndrome is a rare, devastating complication that may result in permanent sensory or motor dysfunction. Early diagnosis and management are paramount for preserving limb function and optimising patient outcomes.

7.
Front Plant Sci ; 15: 1403226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39290732

RESUMO

Plant-associated microbial communities are crucial for plant growth and health. However, assembly mechanisms of microbial communities and microbial interaction patterns remain elusive across vary degrees of pathogen-induced diseases. By using 16S rRNA high-throughput sequencing technology, we investigated the impact of wildfire disease on the microbial composition and interaction network in plant three different compartments. The results showed that pathogen infection significantly affect the phyllosphere and rhizosphere microbial community. We found that the primary sources of microbial communities in healthy and mildly infected plants were from the phyllosphere and hydroponic solution community. Mutual exchanges between phyllosphere and rhizosphere communities were observed, but microbial species migration from the leaf to the root was rarely observed in severely infected plants. Moreover, wildfire disease reduced the diversity and network complexity of plant microbial communities. Interactions among pathogenic bacterial members suggested that Caulobacter and Bosea might be crucial "pathogen antagonists" inhibiting the spread of wildfire disease. Our study provides deep insights into plant pathoecology, which is helpful for the development of novel strategies for phyllosphere disease prediction or prevention.

8.
Front Cell Dev Biol ; 12: 1464337, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39291266

RESUMO

After the endocytic and biosynthetic pathway converge, they partially share the route to the lysosome/vacuole. Similarly, the endocytic recycling and secretory pathways also partially share the route to the plasma membrane. The interaction of these transport pathways is mediated by endosomes and the trans-Golgi network (TGN), which act as sorting stations in endocytic and biosynthesis pathway, and endosomes has a bidirectional transport to and from the TGN. In mammalian cells endosomes can be largely classified as early/sorting, late, and recycling endosomes, based on their morphological features and localization of Rab family proteins, which are key factors in vesicular trafficking. However, these endosomes do not necessarily represent specific compartments that are comparable among different species. For instance, Rab5 localizes to early endosomes in mammalian cells but is widely localized to early-to-late endosomes in yeast, and to pre-vacuolar endosomes and the TGN in plant cells. The SNARE complexes are also key factors widely conserved among species and localized specifically to the endosomal membrane, but the localization of respective homologs is not necessarily consistent among species. These facts suggest that endosomes should be classified more inclusively across species. Here we reconsider the mammalian endosome system based on findings in budding yeast and other species and discuss the differences and similarities between them.

9.
Heliyon ; 10(17): e37057, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39286135

RESUMO

Background: The present study aimed to investigate the relationship between swollen limb circumference and compartment pressure after a snakebite and to evaluate the diagnostic value of the circumference difference between the healthy and affected sides and the circumference growth rate for snake venom-induced compartment syndrome (CS). Method: The study was based on a prospective cohort study of snakebite patients at the emergency department of West China Hospital from May 2021 to October 2022. The snakebite patients were divided into the CS and non-compartment syndrome (NCS) groups. The diagnostic value of the circumference of the swollen limb for the CS after snakebite was evaluated using a receiver-operating characteristic curve analysis, and the cut-off value of the circumference of the swollen limb for CS after snakebite was calculated with sensitivity and specificity. Result: The present study enrolled 115 patients with severely swollen limbs after snakebite. The mean age was 59.1 ± 13.6 years, with 58 (50.4 %) female cases and 57 (49.6 %) male cases. There were 33 (28.7 %) cases where the upper limbs were injured and 82 (71.3 %) cases where the lower limbs were injured. These patients were divided into CS (n = 19) and NCS (n = 96) groups. The area under the curve (AUC) for the 15 cm circumference difference and circumferential growth rate of the upper edge of the patella was 0.683 (95 % CI 0.508 to 0.858, P = 0.037), and 0.685 (95 % CI 0.512 to 0.858, P = 0.035). The optimal cut-off values for the 15 cm circumference difference and circumferential growth rate of the upper edge of the patella to distinguish CS and NCS were 2.8 cm (sensitivity = 76.9 %, specificity = 66.7 %) and 7 % (sensitivity = 76.9 %, specificity = 66.7 %), respectively. Conclusion: Limb circumference measurement is a non-invasive, convenient, effective, and repeatable bedside test that can assist clinicians in the early detection of suspected snake venom-induced CS in patients exhibiting limb swelling after snake bites.

10.
J Exp Orthop ; 11(3): e70017, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39296360

RESUMO

Purpose: To identify patient characteristics associated with forearm chronic exertional compartment syndrome (CECS) and to demonstrate the distribution of intramuscular pressure (IMP) values at 1 min postexercise in a cohort of patients with exercise-induced forearm pain. Methods: A consecutive series of 99 patients seeking orthopaedic consultation for chronic exertional forearm pain underwent IMP measurements between 2010 and 2023. The diagnosis of CECS was confirmed (n = 34) or ruled out (n = 65) based on the patient's history, clinical examination and IMP measurements. Results: There were significantly more male patients in the CECS group than in the group of patients where the diagnosis was ruled out. Furthermore, a significantly higher proportion of the CECS patients had been previously treated for CECS of the lower legs. The most common occupation was office worker (21%), followed by craftsperson (18%). The most common main physical activities were strength training (21%) and cycling (15%). The median (range) 1-min postexercise IMP values for patients with CECS were 34 (23-68) mmHg for the flexor compartment and 32 (25-67) mmHg for the extensor compartment. Conclusion: This study demonstrates a more general population of CECS patients compared to previous studies. Notably, more than a fifth of the CECS patients had previously been treated for CECS in the lower legs. Importantly, considering the 95% confidence interval for IMP values in patients without CECS, the most used IMP cutoff value for diagnosing CECS appears to be too high for the forearm compartments. Level of Evidence: Level II.

11.
Orthop Traumatol Surg Res ; : 104001, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39313023

RESUMO

BACKGROUND: Chronic Exertional Compartment Syndrome (CECS) of the forearm is characterized by an increase of the pressure in the forearm compartments during repeated activities. Its diagnosis is challenging because of the lack of clearly established diagnostic criteria. PURPOSE: We aimed to provide a comprehensive description of the diagnostic methods used for CECS of the forearm, to assess if a more effective diagnosis strategy could be identified. METHODS: We used PubMed, Google Scholar, Cochrane Library and Science Direct databases to search articles. We carried out multiple searches using the mesh terms ("Chronic Exertional Compartment Syndrome" OR "Chronic compartment syndrome" OR "Exertional compartment") AND ("forearm" OR "upper limb"). Inclusion criteria were prospective or retrospective studies on CECS of the forearm including case reports. We used PRISMA guidelines. The included studies were critically appraised using GRADE approach. RESULTS: A total of 625 articles were screened and 33 studies were included. It represented 590 patients (505 men and 85 women), with a mean age of 26.6 years old. Among them, 282 competed at an elite level. Motorcycling and motocross were the most frequent sports (66%). Six diagnostic methods were employed. Intra-compartmental pressure (ICP) measurement was the most frequently used method in 26 studies. Magnetic resonance imaging was performed in 9 studies, while electromyography was employed in only 2 studies. One study reported the measurement of grip strength using a manual dynamometer, one study compared forearm circumference before and after effort, and one used myotonometry. Various exercise protocols were observed. Stress-testing using a hand-grip was the most common protocol in 14 studies. Exercise duration varied from 2 min to 60 min. CONCLUSION: Existing data do not provide sufficient evidence to favor an alternative diagnostic method over ICP measurements that should be used cautiously given the absence of formal validation. Non-invasive methods might be easier to use, but should be subjected to further research. LEVEL OF EVIDENCE: III.

12.
Artigo em Alemão | MEDLINE | ID: mdl-39304586

RESUMO

This article reports on a complicated case of a soft tissue defect with challenging soft tissue coverage on the lower leg. After a lower leg fracture and treatment with a tibial nail, a 29-year-old man developed compartment syndrome due to massive secondary bleeding with a lesion of the common peroneal nerve and muscle necrosis around the fibular muscles. The initial coverage with split skin showed no tendency to heal, so the patient was admitted to this hospital with a soft tissue defect of approximately 25 cm × 10 cm on the lateral lower leg with an exposed tibia over a length of 15 cm. The primary attempt was coverage with a split-thickness skin graft after secondary granulation; however, due to the previously damaged vascular supply, the wound demonstrated a delayed incomplete healing over 8 months. In addition, X­ray imaging revealed a nonunion and a resulting screw fracture of the two distal locking screws. The indications for revision surgery to treat the fracture and change the implant were fulfilled. In the same procedure, the residual cutaneous defects were closed. Given the previously complication-prone course and a difficult local blood flow situation, the choice of reconstruction procedures was limited. A bridge flap of the medial lower leg was performed in an interdisciplinary approach. The lifting defect was covered with split-thickness skin. In this way, the wound was finally adequately covered after 1 year.

13.
Injury ; 55(11): 111879, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39305834

RESUMO

INTRODUCTION: Tibial plateau fractures are often associated with high-energy trauma necessitating external fixation as a means of temporization. There is evidence that pin placement and fracture distraction may result in transient increases in compartment pressures, and the optimal timing of external fixator placement is unknown. This study sought to determine the effect of early versus late external fixator placement on the risk of compartment syndrome after a tibial plateau fracture. METHODS: The Trauma Quality Improvement Program was retrospectively queried between 2015 and 2019 for adult patients with a tibial plateau fracture who underwent external fixator placement. Patients with concomitant tibial shaft and/or distal femur fractures, requiring lower extremity fasciotomy before external fixation, or external fixation >7 days after admission were excluded. The primary study outcome was inpatient compartment syndrome. Secondary outcomes were inpatient acute respiratory failure/unplanned intubation, surgical site infection, and venous thromboembolism (VTE). A time threshold of delayed external fixation was identified at which the odds of compartment syndrome no longer significantly decreased with increasing time using a Markov Chain Monte Carlo simulation of a restricted cubic spline model. The odds of each outcome were compared between patients who underwent early versus delayed external fixation on or after the time threshold, adjusting for potential confounding by patients, injury, and hospital characteristics. Significance was defined as p < 0.05. RESULTS: A threshold for delayed external fixation was identified at 28.8 h from admission. Of the 3,185 eligible patients, 2,656 (83.4 %) were classified as early external fixation and 529 (16.6 %) were classified as delayed external fixation. Delayed external fixation was associated with lower adjusted odds (aOR) of compartment syndrome (aOR: 0.31, 95 % Confidence Interval (CI): 0.13-0.74, p = 0.008) and higher aOR of acute respiratory failure/unplanned intubation (aOR: 2.13, 95 % CI: 1.13-4.0.2, p = 0.019), however no significant differences in adjusted odds of surgical site infection or VTE were observed. CONCLUSION: Patients with tibial plateau fractures who underwent closed reduction and external fixation within 28.8 h of admission were associated with greater odds of compartment syndrome than those undergoing external fixation after this time threshold.

14.
Environ Res ; 263(Pt 1): 120006, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39299448

RESUMO

The impacts of transgenic crops on soil microbiology and fertility are critical in determining their biosafety. While transgenic crops can alter soil microbes, their effects are often context-dependent; therefore, the ecological importance of these changes remains a topic of ongoing research. Using high-throughput sequencing, we investigated the effects of Bacillus thuringiensis (Bt) maize expressing the mcry1Ab and mcry2Ab genes (2A7) on soil nutrient dynamics, as well as the diversity and function of soil microbial communities, including bacteria and fungi, within different soil compartments. Our findings revealed a plant-shaped rhizosphere (RS) microbial community as a result of the selective recruitment of microorganisms from the surrounding environment. The transgene insertion had a significant impact on the RS niche, and several species eventually became associated with Z58 and 2A7 plants. For example, Neocosmospora rubicola fungal and Pantoea dispersa bacterial microorganisms were significantly decreased in the dual Bt-transgenic 2A7 rhizosphere but enriched in the Z58 rhizospheres. The activity of soil enzymes such as urease, invertase, and alkaline phosphatase was boosted by Bt-transgenic 2A7. LefSe analysis identified significant bacterial and fungal biomarker species that were responsible for the differential effects of Bt-transgenic 2A7 and control Z58 within rhizosphere soils. Mantel analysis further demonstrated that the root exudates of 2A7 altered nutrient-acquisition enzymes by influencing biomarker taxa. PICRUSt2 functional characterization revealed a significantly higher abundance of the phosphate-starvation-inducible protein in control Z58 than in Bt-transgenic 2A7. Furthermore, taxonomy, alpha (Shannon diversity), and beta diversity analyses all revealed niche-driven microbial profile differentiation. Niche partitioning also had a significant impact on N- and P-related COGs as well. Our findings suggests that Bt-transgenic 2A7 modulates rhizosphere microbial communities by affecting biomarker taxa and soil enzyme activity. These findings will promote sustainable agriculture practices by advancing our knowledge of the ecological effects of Bt crops on soil microbial communities.

15.
J Orthop Case Rep ; 14(9): 141-146, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39253672

RESUMO

Introduction: Compartment syndrome as a complication during intramedullary nailing of closed tibia fractures was first documented as early as 1980. Case Report: We report a case of a 19-year-old young man victim of a road accident (motorcycle accident) causing an uncomplicated closed fracture of 2 bones of the left leg. The patient underwent centromedullary nailing of the tibia. The evolution was marked by the early onset of an acute and serious compartment syndrome. Conclusion: The first symptom of compartment syndrome is pain regardless of the severity of the trauma. The diagnosis is clinical and is generally confirmed by measuring the pressure in the muscle compartment. The treatment is fasciotomy.

16.
J Surg Case Rep ; 2024(9): rjae582, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39267909

RESUMO

This report describes two similar cases in which the distal forearm was compressed between the rib cage and floor for a prolonged period owing to immobility, resulting in severe compartment syndrome and extensive penetrating necrosis in the forearm. The cases were a 59-year-old man with cervical spondylolisthesis and a 65-year-old man suspected of having Parkinson's disease. A distinctive necrotic pattern characterized by necrosis in the volar and dorsal compartments, preservation of the lateral compartment, and retention of the radial artery was commonly observed in both cases. Despite the anticipated nonfunctional outcome of the salvaged limb, a two-lobed free latissimus dorsi musculocutaneous flap transfer with interposition of the thoracodorsal nerve in the median nerve defect was performed in both cases. Although the salvaged limbs were nonfunctional, the patients were able to use it for activities such as getting up and other daily tasks.

18.
Artigo em Inglês | MEDLINE | ID: mdl-39256215

RESUMO

AIM: The recently introduced Long-Axial-Field-of-View (LAFOV) PET-CT scanners allow for the first-time whole-body dynamic- and parametric imaging. Primary aim of this study was the comparison of direct and indirect Patlak imaging as well as the comparison of different time frames for Patlak calculation with the LAFOV PET-CT in oncological patients. Secondary aims of the study were lesion detectability and comparison of Patlak analysis with a two-tissue-compartment model (2TCM). METHODOLOGY: 50 oncological patients with 346 tumor lesions were enrolled in the study. All patients underwent [18F]FDG PET/CT (skull to upper thigh). Here, the Image-Derived-Input-Function) (IDIF) from the descending aorta was used as the exclusive input function. Four sets of images have been reviewed visually and evaluated quantitatively using the target-to-background (TBR) and contrast-to-noise ratio (CNR): short-time (30 min)-direct (STD) Patlak Ki, short-time (30 min)-indirect (STI) Patlak Ki, long-time (59.25 min)-indirect (LTI) Patlak Ki, and 50-60 min SUV (sumSUV). VOI-based 2TCM was used for the evaluation of tumor lesions and normal tissues and compared with the results of Patlak model. RESULTS: No significant differences were observed between the four approaches regarding the number of tumor lesions. However, we found three discordant results: a true positive liver lesion in all Patlak Ki images, a false positive liver lesion delineated only in LTI Ki which was a hemangioma according to MRI and a true negative example in a patient with an atelectasis next to a lung tumor. STD, STI and LTI Ki images had superior TBR in comparison with sumSUV images (2.9-, 3.3- and 4.3-fold higher respectively). TBR of LTI Ki were significantly higher than STD Ki. VOI-based k3 showed a 21-fold higher TBR than sumSUV. Parameters of different models vary in their differential capability between tumor lesions and normal tissue like Patlak Ki which was better in normal lung and 2TCM k3 which was better in normal liver. 2TCM Ki revealed the highest correlation (r = 0.95) with the LTI Patlak Ki in tumor lesions group and demonstrated the highest correlation with the STD Patlak Ki in all tissues group and normal tissues group (r = 0.93 and r = 0.74 respectively). CONCLUSIONS: Dynamic [18F]-FDG with the new LAFOV PET/CT scanner produces Patlak Ki images with better lesion contrast than SUV images, but does not increase the lesion detection rate. The time window used for Patlak imaging plays a more important role than the direct or indirect method. A combination of different models, like Patlak and 2TCM may be helpful in parametric imaging to obtain the best TBR in the whole body in future.

19.
Artigo em Inglês | MEDLINE | ID: mdl-39224026

RESUMO

Despite improvements in implant design, surgical techniques and assistive technologies for total knee arthroplasty (TKA), anterior knee pain (AKP) remains frequently reported, even by satisfied patients. This persistent problem calls for better understanding and management of the patellofemoral or anterior compartment during surgery, just as the techniques and strategies deployed to optimize the flexion and extension spaces through personalized alignment, bone cuts and ligament balancing. Assistive technologies such as navigation and robotics provide new tools to manage this 'third space' through precise pre-operative planning and dynamic intra-operative assessment. Such endeavors must start with clear definitions of the 'third space', how it should be measured, what constitutes its 'safe zone', and how it affects outcomes. There are yet no established methods to evaluate the patellofemoral compartment, and no clear thresholds to define over- or under-stuffing. Static assessment using lateral radiographs provides a limited understanding and depends considerably on flexion angle, while dynamic evaluation at multiple flexion angles or using intra-operative computer or robotic-assistance enables a broader perspective and solutions to manage patellar tracking and anterior offset. Future studies should investigate the impact of variations in anterior offset in TKA, define its safe zone, and understand the effects of of thresholds for over- or under-stuffing. Experimental methods such as in-vivo motion analysis and force sensors could elucidate the influence of anterior offset on flexion and extension biomechanics.

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