scholarly journals An Early Detection of Acute Compartment Syndrome in Fastened Zip-Tie Rat Model Using Dynamic Phosphorous-31 Magnetic Resonance Spectroscopy at 9.4 Tesla

Author(s):  
Hiroki Ohta ◽  
Nhat-Minh Van Vo ◽  
Junichi Hata ◽  
Koshiro Terawaki ◽  
Takako Shirakawa ◽  
...  

Abstract IntroductionAcute compartment syndrome (ACS) leads to a series of health problems, limb salvage, disability, and even death. In vivo phosphorus-31 magnetic resonance spectroscopy (31P-MRS) provides a unique non-invasive method to assess skeletal muscle metabolisms such as inorganic phosphate (Pi), phosphocreatine (PCr), and adenosine triphosphate (ATP). The study aims to assess the ability of dynamic 31P-MRS in the early detection of muscular damage in ACS.Materials & MethodsThe study induced the fastened zip-tie model of ACS on normotensive Sprague-Dawley rats (n = 6). The spectra were acquired in Bruker 9.4-Tesla preclinical scanner using 1H/31P surface coil. 31P-MRS spectra and blood samples were obtained at time 0 (pre-ischemic phase) and every 15 minutes during the compression (120 minutes) and the reperfusion phase (90 minutes). 31P-MRS spectra findings were compared with plasma creatine phosphokinase (CPK).ResultsPCr/(Pi + PCr) ratio significantly decreased after muscle was compressed (P < 0.05). In contrast to this, CPK did not change significantly (P > 0.05). Both intracellular pH and arterial pH decreased over time. However, intracellular declined significantly (P < 0.05) at 60 minutes of ischemic state, and at 5 minutes and 60 minutes of reperfusion, while arterial pH slightly changed. After 30 minutes of ischemic, phosphomonoesters (PME) peak was detected, which was not seen at the pre-ischemic phase. It gradually increased and reached its highest peak at 120 minutes. At reperfusion state, 31P-MRS spectra and pH did not fully recover to their pre-ischemic state, and PME peak disappeared. There was a correlation between T2-weighted images and CPK from blood tests (R2 = 0.1996, P < 0.05).ConclusionsDynamic 31P-MRS technique is more clearly and rapidly detect the bioenergetic and mitochondrial functions change than blood test in a fastened zip-tie rat model of ACS. This technique is a promising non-invasive method to detect the early ischemic muscular damage in ACS.

Diagnostics ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 586
Author(s):  
Hiroki Ohta ◽  
Nhat-Minh Van Vo ◽  
Junichi Hata ◽  
Koshiro Terawaki ◽  
Takako Shirakawa ◽  
...  

Introduction: Disasters, including terrorism and earthquakes, are significant threats to people and may lead to many people requiring rescue. The longer the rescue takes, the higher the chances of an individual contracting acute compartment syndrome (ACS). ACS is fatal if diagnosed too late, and early diagnosis and treatment are essential. Objective: To assess the ability of dynamic phosphorus magnetic resonance spectroscopy (31P-MRS) in the early detection of muscular damage in ACS. Materials and Methods: Six ACS model rats were used for serial 31P-MRS scanning (9.4 Tesla). Skeletal muscle metabolism, represented by the levels of phosphocreatine (PCr), inorganic phosphate (Pi), and adenosine triphosphate (ATP), was assessed. The PCr/(Pi + PCr) ratio, which decreases with ischemia, was compared with simultaneously sampled plasma creatine phosphokinase (CPK), a muscle damage marker. Results: The PCr/(Pi + PCr) ratio significantly decreased after inducing ischemia (from 0.86 ± 0.10 to 0.18 ± 0.06; p < 0.05), while CPK did not change significantly (from 89 ± 29.46 to 241.50 ± 113.28; p > 0.05). The intracellular and arterial pH index decreased over time, revealing significant differences at 120 min post-ischemia (from 7.09 ± 0.01 to 6.43 ± 0.13, and from 7.47 ± 0.03 to 7.39 ± 0.04, respectively). In the reperfusion state, the spectra and pH did not return to the original values. Conclusions: The dynamic 31P-MRS technique can rapidly detect changes in muscle bioenergetics. This technique is a promising non-invasive method for determining early muscular damage in ACS.


Author(s):  
Jordan David Fliss ◽  
Brandon Zanette ◽  
Yonni Friedlander ◽  
Siddharth Sadanand ◽  
Andras A Lindenmaier ◽  
...  

Premature infants often require mechanical ventilation and oxygen therapy which can result in bronchopulmonary dysplasia (BPD), characterized by developmental arrest and impaired lung function. Conventional clinical methods for assessing the prenatal lung are not adequate for the detection and assessment of long-term health risks in infants with BPD, highlighting the need for a non-invasive tool for the characterization of lung microstructure and function. Theoretical diffusion models, like the Model of Xenon Exchange (MOXE), interrogate alveolar gas exchange by predicting the uptake of inert Hyperpolarized (HP) 129Xe gas measured with HP 129Xe magnetic resonance spectroscopy (MRS). To investigate HP 129Xe MRS as a tool for non-invasive characterization of pulmonary microstructural and functional changes in vivo, HP 129Xe gas exchange data were acquired in an oxygen exposure rat model of BPD that recapitulates the fewer and larger distal airways and pulmonary vascular stunting characteristics of BPD. Gas exchange parameters from MOXE, including airspace mean chord length (L­m), apparent hematocrit in the pulmonary capillaries (HCT), and pulmonary capillary transit time (tx), were compared with airspace mean axis length and area density (MAL and ρ­A) and percentage area of tissue and air (PTA and PAA) from histology. L­m was significantly larger in the exposed rats (p=0.003) and correlated with MAL, ρ­A, PTA, and PAA (0.59<|ρ|<0.66 and p<0.05). Observed increase in HCT (p=0.012) and changes in tx are also discussed. These findings support the use of HP 129Xe MRS for detecting fewer, enlarged distal airways in this rat model of BPD, and potentially in humans.


2021 ◽  
Vol 15 (3) ◽  
pp. 72-79
Author(s):  
Viktoriya V. Sinkova ◽  
Irina A. Krotenkova ◽  
Alina A. Lyaskovik ◽  
Rodion N. Konovalov ◽  
Marina V. Krotenkova

Magnetic resonance spectroscopy is an important non-invasive method that measures concentration and spatial distribution of certain biochemically significant tissue metabolites. This relatively new method has now evolved from a research tool to an independent diagnostic neuroimaging method, which provides answers to a number of important clinical and diagnostic questions at the early stages of the disease, and allows evaluation of treatment efficacy and determination of clinical outcome. The article provides a review of data on sodium magnetic resonance spectroscopy, which is a very sensitive method for assessing cell viability and ion homeostasis. It can be used to measure early biochemical disturbances in the tissues in various degenerative diseases. We describe pathophysiology and technology underlying sodium magnetic resonance spectroscopy, as well as the most promising points of application of this method in central nervous system disorders seen by radiologists and neurologists in their clinical practice.


Author(s):  
Sandra Pérez Rial ◽  
Esther Barreiro Portela ◽  
María Jesús Fernández Aceñero ◽  
María Encarnación Fernández Valle ◽  
Nicolás González Mangado ◽  
...  

Author(s):  
T. N. Trofimova ◽  
A. D. Khalikov ◽  
M. D. Semenova ◽  
A. A. Bogdan

The article demonstrates the first Russian experience of prenatal proton magnetic resonance spectroscopy (1Н MRS) of the brain. The results of the study are analyzed, the metabolic changes during the gestation period is evaluated. Neuroimaging methods of assessing brain metabolism may play a role in the diagnosis and prognosis of some perinatal neurological disorders, that is why the information about normal cerebral metabolic processes is extremely important. Prenatal 1Н MRS of the brain is an informative, non invasive diagnostic method that is performed complementary to MRI and provides unique information about the cerebral biochemical composition. Brain metabolic changes may precede structural, e.g. the appearance of changes in the spectrograms may outgo the changes in traditional MRI, therefore, the method may be useful in the early detection of a pathology. Early detection of abnormal metabolic brain processes may be helpful in identifying future potential therapeutic strategies.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Vinicius da Eira Silva ◽  
Vitor de Salles Painelli ◽  
Samuel Katsuyuki Shinjo ◽  
Wagner Ribeiro Pereira ◽  
Eduardo Maffud Cilli ◽  
...  

2021 ◽  
Vol 3 (Supplement_1) ◽  
pp. i2-i2
Author(s):  
Georgios Batsios ◽  
Celine Taglang ◽  
Meryssa Tran ◽  
Anne Marie Gillespie ◽  
Joseph Costello ◽  
...  

Abstract Telomere shortening constitutes a natural barrier to uncontrolled proliferation and all tumors must find a mechanism of maintaining telomere length. Most human tumors, including high-grade primary glioblastomas (GBMs) and low-grade oligodendrogliomas (LGOGs) achieve telomere maintenance via reactivation of the expression of telomerase reverse transcriptase (TERT), which is silenced in normal somatic cells. TERT expression is, therefore, a driver of tumor proliferation and, due to this essential role, TERT is also a therapeutic target. However, non-invasive methods of imaging TERT are lacking. The goal of this study was to identify magnetic resonance spectroscopy (MRS)-detectable metabolic biomarkers of TERT expression that will enable non-invasive visualization of tumor burden in LGOGs and GBMs. First, we silenced TERT expression by RNA interference in patient-derived LGOG (SF10417, BT88) and GBM (GS2) models. Our results linked TERT silencing to significant reductions in steady-state levels of NADH in all models. NADH is essential for the conversion of pyruvate to lactate, suggesting that measuring pyruvate flux to lactate could be useful for imaging TERT status. Recently, deuterium (2H)-MRS has emerged as a novel, clinically translatable method of monitoring metabolic fluxes in vivo. However, to date, studies have solely examined 2H-glucose and the use of [U-2H]pyruvate for non-invasive 2H-MRS has not been tested. Following intravenous injection of a bolus of [U-2H]pyruvate, lactate production was higher in mice bearing orthotopic LGOG (BT88 and SF10417) and GBM (GS2) tumor xenografts relative to tumor-free mice, suggesting that [U-2H]pyruvate has the potential to monitor TERT expression in vivo. In summary, our study, for the first time, shows the feasibility and utility of [U-2H]pyruvate for in vivo imaging. Importantly, since 2H-MRS can be implemented on clinical scanners, our results provide a novel, non-invasive method of integrating information regarding a fundamental cancer hallmark, i.e. TERT, into glioma patient management.


QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
A A Hafez ◽  
M A Nasr ◽  
N L Salman

Abstract Background Exclusion of malignancy in ovarian mass is of paramount importance. It is the most crucial step after identification of a mass and it has a profound effect on the patient's management. So, a reliable method with which to differentiate a benign from a malignant ovarian mass would provide a basis for optimal preoperative planning and may also reduce the number of unnecessary laparotomies for patients undergoing treatment for benign disease. Objective The aim of our study is to highlight the role of magnetic resonance spectroscopy as a non-invasive technique which may effectively assist in differentiating benign from malignant ovarian masses. Patients and Methods This study included 20 patients with adnexal masses as suggested by preliminary pelvic ultrasound examination. referred from the Gynecology Department to the Radiology Department at Ain shams university hospitals. nine were benign, two were borderline, and six were malignant tumors and 3 were hemorrhagic cyst. Endometriosis, tubo-ovarian abscess. Results Our study revealed sharp choline peak in some benign as well as some malignant cases and so Cho peak could not help in the differential diagnosis between benign and malignant tumors, creatine, lipid and NAA were detected in both benign and malignant tumors, also Choline/Creatine Ratio fairly can differentiate between benign and malignant tumors with cut off point = 3.750 at sensitivity = 75.0% & specificity = 100.0% . Conclusion Our study had some factors that affect the results. First, the sample size were not enough to achieve a good results, second, diversity of samples and the complicated tumor histopathologic and morphologic features.


Sign in / Sign up

Export Citation Format

Share Document