Journal of Clinical and Diagnostic Research, ISSN - 0973 - 709X

Users Online : 4019

AbstractMaterial and MethodsResultsDiscussionConclusionReferencesDOI and Others
Article in PDF How to Cite Citation Manager Readers' Comments (0) Audio Visual Article Statistics Link to PUBMED Print this Article Send to a Friend
Advertisers Access Statistics Resources

Dr Mohan Z Mani

"Thank you very much for having published my article in record time.I would like to compliment you and your entire staff for your promptness, courtesy, and willingness to be customer friendly, which is quite unusual.I was given your reference by a colleague in pathology,and was able to directly phone your editorial office for clarifications.I would particularly like to thank the publication managers and the Assistant Editor who were following up my article. I would also like to thank you for adjusting the money I paid initially into payment for my modified article,and refunding the balance.
I wish all success to your journal and look forward to sending you any suitable similar article in future"



Dr Mohan Z Mani,
Professor & Head,
Department of Dermatolgy,
Believers Church Medical College,
Thiruvalla, Kerala
On Sep 2018




Prof. Somashekhar Nimbalkar

"Over the last few years, we have published our research regularly in Journal of Clinical and Diagnostic Research. Having published in more than 20 high impact journals over the last five years including several high impact ones and reviewing articles for even more journals across my fields of interest, we value our published work in JCDR for their high standards in publishing scientific articles. The ease of submission, the rapid reviews in under a month, the high quality of their reviewers and keen attention to the final process of proofs and publication, ensure that there are no mistakes in the final article. We have been asked clarifications on several occasions and have been happy to provide them and it exemplifies the commitment to quality of the team at JCDR."



Prof. Somashekhar Nimbalkar
Head, Department of Pediatrics, Pramukhswami Medical College, Karamsad
Chairman, Research Group, Charutar Arogya Mandal, Karamsad
National Joint Coordinator - Advanced IAP NNF NRP Program
Ex-Member, Governing Body, National Neonatology Forum, New Delhi
Ex-President - National Neonatology Forum Gujarat State Chapter
Department of Pediatrics, Pramukhswami Medical College, Karamsad, Anand, Gujarat.
On Sep 2018




Dr. Kalyani R

"Journal of Clinical and Diagnostic Research is at present a well-known Indian originated scientific journal which started with a humble beginning. I have been associated with this journal since many years. I appreciate the Editor, Dr. Hemant Jain, for his constant effort in bringing up this journal to the present status right from the scratch. The journal is multidisciplinary. It encourages in publishing the scientific articles from postgraduates and also the beginners who start their career. At the same time the journal also caters for the high quality articles from specialty and super-specialty researchers. Hence it provides a platform for the scientist and researchers to publish. The other aspect of it is, the readers get the information regarding the most recent developments in science which can be used for teaching, research, treating patients and to some extent take preventive measures against certain diseases. The journal is contributing immensely to the society at national and international level."



Dr Kalyani R
Professor and Head
Department of Pathology
Sri Devaraj Urs Medical College
Sri Devaraj Urs Academy of Higher Education and Research , Kolar, Karnataka
On Sep 2018




Dr. Saumya Navit

"As a peer-reviewed journal, the Journal of Clinical and Diagnostic Research provides an opportunity to researchers, scientists and budding professionals to explore the developments in the field of medicine and dentistry and their varied specialities, thus extending our view on biological diversities of living species in relation to medicine.
‘Knowledge is treasure of a wise man.’ The free access of this journal provides an immense scope of learning for the both the old and the young in field of medicine and dentistry as well. The multidisciplinary nature of the journal makes it a better platform to absorb all that is being researched and developed. The publication process is systematic and professional. Online submission, publication and peer reviewing makes it a user-friendly journal.
As an experienced dentist and an academician, I proudly recommend this journal to the dental fraternity as a good quality open access platform for rapid communication of their cutting-edge research progress and discovery.
I wish JCDR a great success and I hope that journal will soar higher with the passing time."



Dr Saumya Navit
Professor and Head
Department of Pediatric Dentistry
Saraswati Dental College
Lucknow
On Sep 2018




Dr. Arunava Biswas

"My sincere attachment with JCDR as an author as well as reviewer is a learning experience . Their systematic approach in publication of article in various categories is really praiseworthy.
Their prompt and timely response to review's query and the manner in which they have set the reviewing process helps in extracting the best possible scientific writings for publication.
It's a honour and pride to be a part of the JCDR team. My very best wishes to JCDR and hope it will sparkle up above the sky as a high indexed journal in near future."



Dr. Arunava Biswas
MD, DM (Clinical Pharmacology)
Assistant Professor
Department of Pharmacology
Calcutta National Medical College & Hospital , Kolkata




Dr. C.S. Ramesh Babu
" Journal of Clinical and Diagnostic Research (JCDR) is a multi-specialty medical and dental journal publishing high quality research articles in almost all branches of medicine. The quality of printing of figures and tables is excellent and comparable to any International journal. An added advantage is nominal publication charges and monthly issue of the journal and more chances of an article being accepted for publication. Moreover being a multi-specialty journal an article concerning a particular specialty has a wider reach of readers of other related specialties also. As an author and reviewer for several years I find this Journal most suitable and highly recommend this Journal."
Best regards,
C.S. Ramesh Babu,
Associate Professor of Anatomy,
Muzaffarnagar Medical College,
Muzaffarnagar.
On Aug 2018




Dr. Arundhathi. S
"Journal of Clinical and Diagnostic Research (JCDR) is a reputed peer reviewed journal and is constantly involved in publishing high quality research articles related to medicine. Its been a great pleasure to be associated with this esteemed journal as a reviewer and as an author for a couple of years. The editorial board consists of many dedicated and reputed experts as its members and they are doing an appreciable work in guiding budding researchers. JCDR is doing a commendable job in scientific research by promoting excellent quality research & review articles and case reports & series. The reviewers provide appropriate suggestions that improve the quality of articles. I strongly recommend my fraternity to encourage JCDR by contributing their valuable research work in this widely accepted, user friendly journal. I hope my collaboration with JCDR will continue for a long time".



Dr. Arundhathi. S
MBBS, MD (Pathology),
Sanjay Gandhi institute of trauma and orthopedics,
Bengaluru.
On Aug 2018




Dr. Mamta Gupta,
"It gives me great pleasure to be associated with JCDR, since last 2-3 years. Since then I have authored, co-authored and reviewed about 25 articles in JCDR. I thank JCDR for giving me an opportunity to improve my own skills as an author and a reviewer.
It 's a multispecialty journal, publishing high quality articles. It gives a platform to the authors to publish their research work which can be available for everyone across the globe to read. The best thing about JCDR is that the full articles of all medical specialties are available as pdf/html for reading free of cost or without institutional subscription, which is not there for other journals. For those who have problem in writing manuscript or do statistical work, JCDR comes for their rescue.
The journal has a monthly publication and the articles are published quite fast. In time compared to other journals. The on-line first publication is also a great advantage and facility to review one's own articles before going to print. The response to any query and permission if required, is quite fast; this is quite commendable. I have a very good experience about seeking quick permission for quoting a photograph (Fig.) from a JCDR article for my chapter authored in an E book. I never thought it would be so easy. No hassles.
Reviewing articles is no less a pain staking process and requires in depth perception, knowledge about the topic for review. It requires time and concentration, yet I enjoy doing it. The JCDR website especially for the reviewers is quite user friendly. My suggestions for improving the journal is, more strict review process, so that only high quality articles are published. I find a a good number of articles in Obst. Gynae, hence, a new journal for this specialty titled JCDR-OG can be started. May be a bimonthly or quarterly publication to begin with. Only selected articles should find a place in it.
An yearly reward for the best article authored can also incentivize the authors. Though the process of finding the best article will be not be very easy. I do not know how reviewing process can be improved. If an article is being reviewed by two reviewers, then opinion of one can be communicated to the other or the final opinion of the editor can be communicated to the reviewer if requested for. This will help one’s reviewing skills.
My best wishes to Dr. Hemant Jain and all the editorial staff of JCDR for their untiring efforts to bring out this journal. I strongly recommend medical fraternity to publish their valuable research work in this esteemed journal, JCDR".



Dr. Mamta Gupta
Consultant
(Ex HOD Obs &Gynae, Hindu Rao Hospital and associated NDMC Medical College, Delhi)
Aug 2018




Dr. Rajendra Kumar Ghritlaharey

"I wish to thank Dr. Hemant Jain, Editor-in-Chief Journal of Clinical and Diagnostic Research (JCDR), for asking me to write up few words.
Writing is the representation of language in a textual medium i e; into the words and sentences on paper. Quality medical manuscript writing in particular, demands not only a high-quality research, but also requires accurate and concise communication of findings and conclusions, with adherence to particular journal guidelines. In medical field whether working in teaching, private, or in corporate institution, everyone wants to excel in his / her own field and get recognised by making manuscripts publication.


Authors are the souls of any journal, and deserve much respect. To publish a journal manuscripts are needed from authors. Authors have a great responsibility for producing facts of their work in terms of number and results truthfully and an individual honesty is expected from authors in this regards. Both ways its true "No authors-No manuscripts-No journals" and "No journals–No manuscripts–No authors". Reviewing a manuscript is also a very responsible and important task of any peer-reviewed journal and to be taken seriously. It needs knowledge on the subject, sincerity, honesty and determination. Although the process of reviewing a manuscript is a time consuming task butit is expected to give one's best remarks within the time frame of the journal.
Salient features of the JCDR: It is a biomedical, multidisciplinary (including all medical and dental specialities), e-journal, with wide scope and extensive author support. At the same time, a free text of manuscript is available in HTML and PDF format. There is fast growing authorship and readership with JCDR as this can be judged by the number of articles published in it i e; in Feb 2007 of its first issue, it contained 5 articles only, and now in its recent volume published in April 2011, it contained 67 manuscripts. This e-journal is fulfilling the commitments and objectives sincerely, (as stated by Editor-in-chief in his preface to first edition) i e; to encourage physicians through the internet, especially from the developing countries who witness a spectrum of disease and acquire a wealth of knowledge to publish their experiences to benefit the medical community in patients care. I also feel that many of us have work of substance, newer ideas, adequate clinical materials but poor in medical writing and hesitation to submit the work and need help. JCDR provides authors help in this regards.
Timely publication of journal: Publication of manuscripts and bringing out the issue in time is one of the positive aspects of JCDR and is possible with strong support team in terms of peer reviewers, proof reading, language check, computer operators, etc. This is one of the great reasons for authors to submit their work with JCDR. Another best part of JCDR is "Online first Publications" facilities available for the authors. This facility not only provides the prompt publications of the manuscripts but at the same time also early availability of the manuscripts for the readers.
Indexation and online availability: Indexation transforms the journal in some sense from its local ownership to the worldwide professional community and to the public.JCDR is indexed with Embase & EMbiology, Google Scholar, Index Copernicus, Chemical Abstracts Service, Journal seek Database, Indian Science Abstracts, to name few of them. Manuscriptspublished in JCDR are available on major search engines ie; google, yahoo, msn.
In the era of fast growing newer technologies, and in computer and internet friendly environment the manuscripts preparation, submission, review, revision, etc and all can be done and checked with a click from all corer of the world, at any time. Of course there is always a scope for improvement in every field and none is perfect. To progress, one needs to identify the areas of one's weakness and to strengthen them.
It is well said that "happy beginning is half done" and it fits perfectly with JCDR. It has grown considerably and I feel it has already grown up from its infancy to adolescence, achieving the status of standard online e-journal form Indian continent since its inception in Feb 2007. This had been made possible due to the efforts and the hard work put in it. The way the JCDR is improving with every new volume, with good quality original manuscripts, makes it a quality journal for readers. I must thank and congratulate Dr Hemant Jain, Editor-in-Chief JCDR and his team for their sincere efforts, dedication, and determination for making JCDR a fast growing journal.
Every one of us: authors, reviewers, editors, and publisher are responsible for enhancing the stature of the journal. I wish for a great success for JCDR."



Thanking you
With sincere regards
Dr. Rajendra Kumar Ghritlaharey, M.S., M. Ch., FAIS
Associate Professor,
Department of Paediatric Surgery, Gandhi Medical College & Associated
Kamla Nehru & Hamidia Hospitals Bhopal, Madhya Pradesh 462 001 (India)
E-mail: drrajendrak1@rediffmail.com
On May 11,2011




Dr. Shankar P.R.

"On looking back through my Gmail archives after being requested by the journal to write a short editorial about my experiences of publishing with the Journal of Clinical and Diagnostic Research (JCDR), I came across an e-mail from Dr. Hemant Jain, Editor, in March 2007, which introduced the new electronic journal. The main features of the journal which were outlined in the e-mail were extensive author support, cash rewards, the peer review process, and other salient features of the journal.
Over a span of over four years, we (I and my colleagues) have published around 25 articles in the journal. In this editorial, I plan to briefly discuss my experiences of publishing with JCDR and the strengths of the journal and to finally address the areas for improvement.
My experiences of publishing with JCDR: Overall, my experiences of publishing withJCDR have been positive. The best point about the journal is that it responds to queries from the author. This may seem to be simple and not too much to ask for, but unfortunately, many journals in the subcontinent and from many developing countries do not respond or they respond with a long delay to the queries from the authors 1. The reasons could be many, including lack of optimal secretarial and other support. Another problem with many journals is the slowness of the review process. Editorial processing and peer review can take anywhere between a year to two years with some journals. Also, some journals do not keep the contributors informed about the progress of the review process. Due to the long review process, the articles can lose their relevance and topicality. A major benefit with JCDR is the timeliness and promptness of its response. In Dr Jain's e-mail which was sent to me in 2007, before the introduction of the Pre-publishing system, he had stated that he had received my submission and that he would get back to me within seven days and he did!
Most of the manuscripts are published within 3 to 4 months of their submission if they are found to be suitable after the review process. JCDR is published bimonthly and the accepted articles were usually published in the next issue. Recently, due to the increased volume of the submissions, the review process has become slower and it ?? Section can take from 4 to 6 months for the articles to be reviewed. The journal has an extensive author support system and it has recently introduced a paid expedited review process. The journal also mentions the average time for processing the manuscript under different submission systems - regular submission and expedited review.
Strengths of the journal: The journal has an online first facility in which the accepted manuscripts may be published on the website before being included in a regular issue of the journal. This cuts down the time between their acceptance and the publication. The journal is indexed in many databases, though not in PubMed. The editorial board should now take steps to index the journal in PubMed. The journal has a system of notifying readers through e-mail when a new issue is released. Also, the articles are available in both the HTML and the PDF formats. I especially like the new and colorful page format of the journal. Also, the access statistics of the articles are available. The prepublication and the manuscript tracking system are also helpful for the authors.
Areas for improvement: In certain cases, I felt that the peer review process of the manuscripts was not up to international standards and that it should be strengthened. Also, the number of manuscripts in an issue is high and it may be difficult for readers to go through all of them. The journal can consider tightening of the peer review process and increasing the quality standards for the acceptance of the manuscripts. I faced occasional problems with the online manuscript submission (Pre-publishing) system, which have to be addressed.
Overall, the publishing process with JCDR has been smooth, quick and relatively hassle free and I can recommend other authors to consider the journal as an outlet for their work."



Dr. P. Ravi Shankar
KIST Medical College, P.O. Box 14142, Kathmandu, Nepal.
E-mail: ravi.dr.shankar@gmail.com
On April 2011
Anuradha

Dear team JCDR, I would like to thank you for the very professional and polite service provided by everyone at JCDR. While i have been in the field of writing and editing for sometime, this has been my first attempt in publishing a scientific paper.Thank you for hand-holding me through the process.


Dr. Anuradha
E-mail: anuradha2nittur@gmail.com
On Jan 2020

Important Notice

Original article / research
Year : 2025 | Month : January | Volume : 19 | Issue : 1 | Page : TC01 - TC06 Full Version

Evaluation of Metabolic Characteristics of Brain Tumours Utilising 31-Phosphorus MR Spectroscopy in 3T MRI: A Cross-sectional Study


Published: January 1, 2025 | DOI: https://doi.org/10.7860/JCDR/2025/67394.20491
Nivetha Kannan, Babu Peter Sathyanathan

1. Assistant Professor, Department of Radiodiagnosis, Madras Medical College, Chennai, Tamil Nadu, India. 2. Head, Department of Radiodiagnosis, Madras Medical College, Chennai, Tamil Nadu, India.

Correspondence Address :
Dr. Babu Peter Sathyanathan,
Head, Department of Radiodiagnosis, Madras Medical College, Chennai-600003, Tamil Nadu, India.
E-mail: drbabupeter@gmail.com

Abstract

Introduction: The characterisation of brain tumours is predominantly based on Magnetic Resonance Imaging (MRI) for structural details and invasive histopathology for certainty. MR spectroscopy, a non invasive technique has provided access to the novel field of metabolomics in-vivo. Proton (H+) MR spectroscopy has gained unanimous acceptance as a neuroimaging technique. In addition, 31-Phosphorus MR spectroscopy provides insight into the energetics of normal and abnormal tissues.

Aim: To metabolically characterise brain tumours and compare them with normal brain parenchyma using 31-Phosphorus spectroscopy by obtaining applicable parameters for evaluation, diagnosis and grading of brain tumours.

Materials and Methods: This cross-sectional study was conducted at the Barnard Institute of Radiology, Madras Medical College, Chennai, Tamil Nadu, India, from December 2019 to December 2021. The study included 32 patients diagnosed with brain tumours based on conventional MR imaging, followed by histopathology, and 10 normal healthy volunteers who underwent 31-Phosphorus MR spectroscopy using a customised birdcage 31-P dual-tuned head coil on a Siemens 3-Tesla MRI scanner (Rapid Biomedical, Wurzburg, Germany). The phosphorus metabolites and ratios analysed included Phosphodiesters {Glycerophosphoethanolamine (GPE) and Glycerophosphocholine (GPC)}, Gamma Adenosine Triphosphate (γ-ATP), Phosphocreatine (PCr), and Inorganic Phosphate (Pi). The metabolite ratios assessed were GPC/GPE, GPC/Pi, GPC/PCr, GPC/γ-ATP, GPE/Pi, GPE/PCr, GPE/γ-ATP, PCr/Pi, PCr/γ-ATP, and Pi/γ-ATP. Additionally, pH was derived. The values were recorded within the tumour, in the peritumoural oedema, and in the normal-appearing contralateral brain parenchyma. These values were compared with each other and also with the brain parenchymal values of the controls. One-way Analysis of Variance (ANOVA) was used to compare the metabolite ratios observed in various sites.

Results: The subjects included 13 females and 19 males, with a mean age of 41.7 years and 43.4 years respectively. A mild alkalinisation trend was observed within the brain tumours (pH 7.1±0.12) compared to the control group (7.05±0.02). Significantly increased GPE/γ-ATP and PCr/γ-ATP values, as well as significantly decreased PCr/Pi values, were observed within the tumour in comparison to the control group (p-value <0.05). Gliomas and metastases showed relatively higher pH compared to the controls (7.05±0.02). High-grade gliomas exhibited alkaline pH compared to low-grade gliomas, with a p-value of 0.000439. Significant differences were noted between gliomas and metastases compared to the control group.

Conclusion: A 31-Phosphorus MR spectroscopy has provided new insights into cellular metabolism in the pathological brain and has enhanced the understanding of the ongoing pathomechanisms in various brain tumours.

Keywords

Glioma, Intracellular pH of brain, Metastasis, 31-P MRS, Brain tumours

The alteration of biochemical pathways has been postulated as the basis of human diseases. It is an understatement to say that knowledge of the biochemistry of pathological tissues will prove useful in the diagnosis, grading, staging, treatment, and response evaluation of diseases. Analytical techniques existing for metabolic analysis, such as gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, and thin-layer chromatography, are performed with biological samples. In contrast, Nuclear Magnetic Resonance Spectroscopy (NMRS) can be done non invasively and in-vivo (1).

Proton MR spectroscopy has become an invaluable tool in the field of neuro-oncology for the characterisation of brain tumours. However, 31-phosphorus MR spectroscopy is a less-exploited potential tool that can elucidate the bioenergetics of normal and pathological tissues in-vivo. The lower concentration of phosphorus metabolites compared to protons in water molecules (2), along with the Larmor frequency of 31-phosphorus being 15 times lower than that of protons (3) leads to reduced sensitivity of the MR spectrum, which has limited the utility of 31-phosphorus MR spectroscopy in clinical practice.

The advantages of 31-phosphorus MR spectroscopy include the natural 100% abundance of Phosphorus-31 Nuclear Magnetic Resonance (31-P NMR) nuclei compared to carbon-13 and oxygen-17, making it easily detectable in spectroscopy. The 31-P spectrum comprises only a few resonance peaks, allowing for precise quantification of metabolites. No suppression techniques are necessary, as is the case with proton spectroscopy, due to the absence of dominant water or fat signals. Additionally, the reduced T1 relaxation time of phosphate metabolites at higher field strengths enables 31-phosphorus MR spectroscopy to be performed with short Repetition Times (TR) (4),(5).

The phosphorus metabolites detected from the spectra include Phosphocreatine (PCr), Inorganic Phosphate (Pi), Adenosine Triphosphate (ATP), Phosphomonoesters (PME), and Phosphodiesters (PDE) (Table/Fig 1). Direct estimation of metabolite concentrations from the spectra can be challenging due to factors such as coil sensitivity, field inhomogeneity, and relaxation time (6).

Hence, metabolite ratios are more commonly used in the evaluation of bioenergetics in both normal and pathological tissues.

The current study is aimed to obtain useful parameters from 31-phosphorus MR spectroscopy for the characterisation of various brain tumours and to evaluate the metabolic differences in various regions of pathological and normal brain tissue for comparison.

Material and Methods

This cross-sectional study was undertaken at the Barnard Institute of Radiology, Madras Medical College, Chennai, Tamil Nadu, India, from December 2019 to December 2021. Local Institutional Ethical Committee approval was sought, and informed written consent was obtained from the study participants before the 31P-MR spectroscopic examination. The study adhered to the revised Declaration of Helsinki 2013.

Inclusion and Exclusion criteria: Consecutive patients undergoing routine clinical brain MRI who were detected to have a brain tumour were included in the study and followed with histopathology. Patients with smaller lesions that could not be evaluated using MR spectroscopy, histopathologically confirmed non-tumourous lesions, lesions with a predominant cystic or haemorrhagic component, and post-radiation lesions were excluded from the study. Eventually, 32 patients were included in the study. In addition, 10 healthy volunteers with no history of recent trauma, infarct, or migraine were also subjected to 31P-MR spectroscopy.

Study Procedure

MR spectroscopy and data acquisition: Conventional MRI was performed using the regular institutional protocol, followed by 31P-MR spectroscopy conducted in a 3-Tesla MRI (Skyra, Siemens Healthineers, Erlangen, Germany) using a customised birdcage 31P dual-tuned head coil (Rapid Biomedical, Wurzburg, Germany) equipped with quadrature polarisation capable of performing 1H decoupling. The coil used had an inner diameter of 26.5 cm and a housing length of 43 cm, weighing approximately 10 kg. For 31P spectroscopy, planning was done in a 3D Magnetic Resonance Spectroscopic Imaging (MRSI) sequence with full phase encoding, a flip angle of 90 degrees, a bandwidth of 1000 Hz, a repetition time of 1500 ms, an echo time of 2.3 ms, an acquisition delay of 2.3 ms, and an acquisition duration of 512 ms. Post-processing was performed on the Siemens workstation Syngovia. The voxel of interest was selected with an extrapolated 8×8×16 matrix and a field of view of 230×230 mm2, resulting in a voxel size of 40.0×40.0×25.0 mm3, and was placed in three selected areas of interest. The regions of interest for the study included contrast-enhancing tumours, non enhancing peritumoural oedema, and contralateral normal-appearing brain parenchyma.

The integral values and ratios undertaken for this study included Phosphodiesters (GPE and GPC), Gamma ATP (γ-ATP), Phosphocreatine (PCr), and Inorganic phosphate (Pi), with metabolite ratios namely GPC/GPE, GPC/Pi, GPC/PCr, GPC/γ-ATP, GPE/Pi, GPE/PCr, GPE/γ-ATP, PCr/Pi, PCr/γ-ATP, and Pi/γ-ATP calculated. In addition, pH was derived by exploiting the chemical shift difference between pH-dependent Inorganic Phosphate (Pi) and a pH-independent reference peak, which was Phosphocreatine (PCr), using two different Henderson-Hasselbalch equations (7),(8),(9).

pH= 6.66+log(δPi-3.08)/5.57-δPi

pH= 6.77+log(δPi-3.29)/5.68-δPi

δpi- difference in chemical shift of Pi and PCr

Statistical Analysis

The statistical analysis was conducted using IBM Statistical Package for the Social Sciences (SPSS) Statistics for Windows, version 23.0 (Armonk, NY: IBM Corp). Categorical variables were evaluated using frequency analysis and percentage analysis, while the mean and Standard Deviation (SD) were used to assess continuous variables. The Mann-Whitney U test was used to determine the significant difference between the high-grade and low-grade gliomas (7 cases of Grade 2 and 5 cases of Grade 4 glioma). To compare metabolite ratios across various brain sites and with the controls, one-way ANOVA was utilised. A probability value of 0.05 was considered significant.

Results

A total of 32 patients, which included 13 females and 19 males, with a mean age of 41.7 years and 43.4 years respectively, were subjected to the study. The histopathological composition of the study group comprised 12 cases of glioma, 11 cases of metastasis, 3 cases of meningioma, 2 cases of ependymoma, and one case each of medulloblastoma, haemangioblastoma, oligodendroglioma, and pituitary macroadenoma. Representative images of pituitary macroadenoma and meningioma with the 31-P spectra are shown in (Table/Fig 2) and (Table/Fig 3)a-c. The control group comprised 10 subjects with a mean age of 40.6 years.

The total scan time for 31-Phosphorus MR spectroscopy was about 15 minutes, including localisation. GPE/γATP and PCr/γATP showed a significant increase within the lesion and in the contralateral normal-appearing brain parenchyma compared to the controls, with p-values of 0.001 and 0.0005, respectively (Table/Fig 4). PCr/Pi values were found to be very low in the control group compared to the lesion, periphery and the normal appearing brain parenchyma with a p value of <0.05 (Table/Fig 2) Increased ratio of Pi/ATP was observed within the normal cells compared to the tumour cells, but the difference was statistically insignificant.

Glioma: In glioma, the intracellular pH recorded was highest within the lesion (pH 7.11±0.09), with decreasing pH in the controls (7.06±0.03) (Table/Fig 5). When comparing high-grade and low-grade gliomas, no significant differences could be observed in the metabolite ratios (Table/Fig 6). A representative image of glioma is shown in (Table/Fig 7). However, an alkaline pH of 7.13 was observed in high-grade gliomas (n=7), compared to 7.05 in low-grade gliomas (n=5), with a significant p-value of 0.000439 (Table/Fig 8).

Metastasis (Table/Fig 9)a-c: Integral value of γATP was significantly lower in brain metastasis compared to normal parenchyma. An alkalinisation tendency was observed within metastasis (pH 7.1±0.09) compared to controls (pH 7.06±0.03). Decreased metabolite ratios of GPE/γATP, GPE/PCr, PCr/γATP, and Pi/γATP were noted within the metastatic lesion in comparison to the control group.

Discussion

31-Phosphorus spectra: 31-P MR spectroscopy provides three basic types of information, namely the energy pool—represented by PCr, Pi and three isotopomers of ATP; the synthesis and degradation of phospholipids, which constitute the cell membrane—represented by PME and phosphodiesters, respectively; and the quantification of intracellular pH and concentration of magnesium (10).

Due to the abundance of PCr in brain tissue, which leads to the dominant signal and relative stability, PCr is assigned a chemical shift of 0 ppm. PCr is a high-energy molecule indicative of mitochondrial oxidative capacity. To the left of PCr are inorganic phosphate and phospholipids. Inorganic phosphate, a compound directly involved in the synthesis of ATP, resonates at 6.5 ppm, while the phospholipids, including PME at 4.9 ppm and phosphodiesters at 2.6 ppm, are found in this region. PME, consisting of Phosphoethanolamine (PE) and Phosphocholine (PC), represents the anabolic activity of cell membranes, as they are the precursors of membrane synthesis. PDE, constituted by Glycerophosphoethanolamine (GPE) and GPC, indicates the catabolism of cell membranes (11). The ratio of PME to PDE is indicative of cell membrane turnover (12).

The three peaks of ATP, the molecular currency of intracellular energy transfer, fall to the right of PCr (γ-, α-, and β-ATP from left to right at -7.8, -16.3, and -2.7 ppm, respectively). ATP, comprising the phosphate groups namely the alpha (α), beta (β), and gamma (γ) phosphates, is typically related to adenosine nucleotide. Energy for anabolic reactions is driven by the hydrolysis of the gamma phosphate group on the ATP molecules. The gamma phosphate has a higher energy of hydrolysis than either the alpha or beta phosphate (13). Thus, the γ phosphate group was taken up for the study.

Intracellular pH: The 31-Phosphorus MR spectroscopy utilises the chemical shift difference between Pi and PCr, using Henderson-Hasselbalch equation for the estimation of pH [7-9]. Contrary to the prevailing theory that tumour cells exhibit acidic pH due to increased production of lactic acid during anaerobic glycolysis, studies using 31-P MR spectroscopy on brain tumours have demonstrated that the intracellular pH in these tumours is alkaline [14-16]. An alkaline pH is essential for the optimal functioning of various enzymes involved in the glycolytic pathway and also enhances key components of cellular proliferation, such as protein, Ribonucleic Acid (RNA), and Deoxyribonucleic Acid (DNA) synthesis. The alkaline environment within tumour cells is maintained by various transporters that move excess H+ ions into the extracellular space, thereby creating an extracellular acidic pH. This process enhances the invasiveness of tumour cells and promotes angiogenesis (14),(17). In coherence with many other similar studies (18),(19),(20), the present research demonstrated a tendency towards alkalinisation within tumour cells, with a mean pH of 7.1±0.12 compared to normal brain tissue.

The normal mean pH of healthy brain parenchyma was calculated to be 7.06±0.03, which corroborates with values from studies (7),(21),(22) but is relatively higher than those found in other studies (23),(24),(25), the mean of which was 7.005. Among all the tumours, the most alkaline pH was observed in ependymomas (7.19±0.09). Gliomas also exhibited an alkaline pH (7.12±0.09), similar to other studies (24),(26) that reported values of 7.092±0.07 and 7.12±0.02, respectively. A gradual decrease in pH was observed within the peritumoural oedema and the contralateral normal brain. High-grade gliomas demonstrated a higher pH (7.13±0.06) compared to low-grade gliomas (7.05±0.02), with a p-value of 0.000439. Although meningiomas showed an alkaline pH (7.05), it was lower compared to a study that reported a pH value of 7.16±0.03 (26). Metastatic tumours exhibited a significantly higher pH (7.10) compared to the non pathological brain, which is consistent with findings from a study that reported a pH of 7.12±0.12 (21) and another study that reported a pH of 7.45±0.56 (22), although all studies were statistically insignificant. Cases of metastasis showed a spectrum of values ranging from acidic to alkaline pH, which could possibly reflect the varied nature of the primary malignancy (22).

Membrane phospholipids metabolism: Membrane phospholipids constitute the cell membrane and are involved in maintaining structural integrity, signal transduction mechanisms, regulation of cellular proliferation, and lipoprotein metabolism, thus playing a major role in tumourigenesis (27),(28). The fixed structural integrity of phospholipids precludes the direct estimation of membrane phospholipids; however, the measurement of precursors and degradation products becomes feasible with 31 Phosphorus MR spectroscopy (29),(30). Since various studies have shown the significant role of PME, the present study attempts to investigate the role of individual phosphodiesters, namely glycerol-3-phosphoethanolamine and glycerol-3-phosphocholine, which contribute to cell wall structure. An increased concentration of these compounds indicates the presence of breakdown products of membrane metabolism. PME and PDE with respect to energy-related metabolites (Pi, PCr, and ATP) reflect tumour growth and cell reproduction rates. The present study showed decreased values of GPE/ATP in brain tumours compared to normal brain, indicating an existing catabolic state.

Gliomas exhibited a decreased ratio of GPE/γATP, and metastatic tumours revealed reduced levels of GPE/γATP and GPE/PCr in comparison with normal brain parenchyma, implying a state of increased catabolism within tumour cells (20),(31),(32). A decreased ratio of PDE/Pi was found within gliomas, although it was statistically insignificant (22),(24). In contrast, present study showed increased levels of GPC/Pi, which is one of the components of phosphodiesters, within gliomas compared to normal brain parenchyma. This possibly indicates varying roles of GPC and GPE, which need to be elucidated.

Cellular energy metabolism: Cellular energy metabolism is a major determinant of cellular proliferation and cell death (28),(33). ATP drives many important cellular processes, such as protein synthesis, synaptic signalling, active transport, and muscle contraction. The intracellular concentration of ATP remains relatively constant, as the rate of ATP generation is linked to the rate of ATP hydrolysis, indicating a high turnover (34). Under normal conditions, ATP is generated predominantly from oxidative phosphorylation within the mitochondria and minimally from the process of glycolysis within the cytosol.

The ATP synthase is a transmembrane protein complex that permits protons to enter the intermembrane space through its concentration gradient and uses the released energy from the process of oxidative phosphorylation to synthesise ATP from Adenosine Diphosphate (ADP) and Inorganic Phosphate (Pi) (35). In addition to oxidative phosphorylation, Creatine Kinase (CK) plays a key role in maintaining cellular energy homeostasis in many metabolically demanding tissues, such as muscle and brain.

During situations of high energy demand or reduced mitochondrial ATP generation, CK facilitates the rapid transfer of a high-energy phosphate group from PCr to ADP through a forward reaction. Consequently, PCr levels decline when ATP levels are minimal, such as during the early onset of heavy exercise and severe ischaemia. Therefore, PCr can be regarded as an energy reservoir that is important for maintaining ATP levels during physiological and pathological states. Contrary to the behaviour of normal cells, tumour cells have a higher demand for metabolic energy (22),(26),(33) and predominantly rely on the process of anaerobic glycolysis, even in the presence of adequate oxygen in the intracellular milieu [10,13]. The increased demand for ATP by tumour cells is met by increasing the transport of glucose into the cells and by accelerating glycolytic processes (15),(17),(28). The present study showed a decreased PCr/ATP ratio in tumour cells compared to normal brain tissue, indicating a negative energetic status within the tumour cells. The PCr/Pi ratio was also comparatively lower in tumour cells, depicting reduced oxidative capacity in comparison to the surrounding tissue and the contralateral normal brain, although this finding was not statistically significant in the present study. This is consistent with findings from other similar studies (20),(22),(31),(32),(36). The lack of ATP causes CK to buffer ATP, resulting in a decrease in PCr and an increase in creatine and Pi. Hence, the Pi/ATP ratio can be used to represent ATP turnover. In line with this theory, brain tumours demonstrated highest values within the tumour compared to the contralateral normal-appearing brain parenchyma. Gliomas showed reduced levels of PCr/Pi and PCr/γATP and increased levels of Pi/ATP compared to normal brain parenchyma, implying increased energy expenditure and ATP turnover, coupled with decreased oxidative capacity and a negative energetic state of tumour cells, possibly due to the presence of necrosis within the tumour cells. High-grade and low-grade gliomas could not be differentiated based on their energetic status.

In the present study, metastatic tumours showed decreased integral values of γATP compared to the controls, with a p-value of 0.002, and also a decreased Pi/ATP ratio, which was contradictory to another study that reported a significant increase in Pi/ATP in the tumour group, including both glioma and metastasis (0.28±0.09) (21). This discrepancy may indicate an increased propensity for necrosis. Reduced levels of PCr/γATP were observed in metastatic tumours, indicating a negative energetic state.

Limitation(s)

Fewer subjects were included, so definitive conclusions and their clinical roles could not be established. Smaller lesions, less than 2 cm, cannot be subjected to 31 Phosphorus MR spectroscopy, and the increased time required, in addition to the conventional MR sequences, can be limiting, particularly in certain groups of patients. Further studies are needed to establish the role of 31-Phosphorus MR spectroscopy as a complementary tool in the evaluation of brain tumours, particularly in cases of uncertainty and in patients with chronic renal diseases where contrast studies may be contraindicated. The main limitation of 31-phosphorus spectroscopy is the limited availability of 31-phosphorus coils due to their extreme cost, which hinders further research and clinical utility.

Conclusion

A 31-Phosphorus MR Spectroscopy appears to be a powerful non invasive tool in the study of energy metabolism in both normal and pathological brains, thus providing a new perspective in the field of metabolomics. Additionally, it can be used in the follow-up of treatment responses and in exploring future dimensions in targeted treatment of brain tumours. The intracellular pH of brain tumours showed alkalinisation and was also found to be helpful in differentiating high-grade from low-grade gliomas. Metabolite ratios such as GPE/γATP and PCr/γATP were found to be useful in differentiating various tumours, similar to other studies. The present study has raised the possibility of varying roles of GPC and GPE, which need further elucidation. Metabolic differences existed in regions of brain distant from the brain tumour which appear normal on imaging in our study reflecting the biochemical alterations in the whole brain.

References

1.
Griffin JL. Shockcor JP. Metabolic profiles of cancer cells. Nat Rev Cancer. 2004;4:551-61. [crossref][PubMed]
2.
Bogner W, Chmelik M, Schmid AI, Moser E, Trattnig S, Gruber S. Assessment of 31P relaxation times in the human calf muscle: a comparison between 3 T and 7 T in vivo. Magnetic Resonance in Medicine: An Official Journal of the International Society for Magnetic Resonance in Medicine. 2009;62(3):574-82. [crossref][PubMed]
3.
Qiao H, Zhang X, Zhu XH, Du F, Chen W. In vivo 31P MRS of human brain at high/ultrahigh fields: a quantitative comparison of NMR detection sensitivity and spectral resolution between 4 T and 7 T. Magnetic Resonance Imaging. 2006;24(10):1281-86. [crossref][PubMed]
4.
Liu Y, Gu Y, Yu X. Assessing tissue metabolism by phosphorous-31 magnetic resonance spectroscopy and imaging: a methodology review. Quantitative Imaging in Medicine and Surgery. 2017;7(6):707. [crossref][PubMed]
5.
Roth K, Hubesch B, Meyerhoff DJ, Naruse S, Gober JR, Lawry TJ, et al. Noninvasive quantitation of phosphorus metabolites in human tissue by NMR spectroscopy. Journal of Magnetic Resonance (1969). 1989;81(2):299-311. [crossref]
6.
Moshkova AN, Khvatova EM, Rusakova IA. Analysis and prediction of ATP concentration in the animal brain under hypoxic conditions. Neurochemical Journal. 2009;3(1):44-48. [crossref]
7.
Cichocka M, Kozub J, Urbanik A. PH measurements of the brain using phosphorus magnetic resonance spectroscopy (31PMRS) in healthy men–comparison of two analysis methods. Polish Journal of Radiology. 2015;80:509. [crossref][PubMed]
8.
Naressi A, Couturier C, Castang I, De Beer R, Graveron-Demilly D. Java-based graphical user interface for MRUI, a software package for quantitation of in vivo/medical magnetic resonance spectroscopy signals. Computers in Biology and Medicine. 2001;31(4):269-86. [crossref][PubMed]
9.
Zhang X, Lin Y, Gillies RJ. Tumour pH and its measurement. Journal of Nuclear Medicine. 2010;51(8):1167-70.[crossref][PubMed]
10.
Komoroski RA, Pearce JM, Mrak RE. 31P NMR spectroscopy of phospholipid metabolites in postmortem schizophrenic brain. Magnetic Resonance in Medicine: An Official Journal of the International Society for Magnetic Resonance in Medicine. 2008;59(3):469-74. [crossref][PubMed]
11.
Cadoux-Hudson TA, Blackledge MJ, Rajagopalan B, Taylor DJ, Radda GK. Human primary brain tumour metabolism in vivo: a phosphorus magnetic resonance spectroscopy study. British Journal of Cancer. 1989;60(3):430-36. [crossref][PubMed]
12.
Ha DH, Choi S, Oh JY, Yoon SK, Kang MJ, Kim KU. Application of 31P MR spectroscopy to the brain tumours. Korean Journal of Radiology. 2013;14(3):477-86. [crossref][PubMed]
13.
Berg JM, Tymoczko JL, Stryer L. Biochemistry (Loose-Leaf). Macmillan; 2007.
14.
Beloueche-Babari M, Chung YL, Al-Saffar NM, Falck-Miniotis M, Leach MO. Metabolic assessment of the action of targeted cancer therapeutics using magnetic resonance spectroscopy. British Journal of Cancer. 2010;102(1):01-07. [crossref][PubMed]
15.
DeBerardinis RJ, Lum JJ, Hatzivassiliou G, Thompson CB. The biology of cancer: metabolic reprogramming fuels cell growth and proliferation. Cell Metab 2008;7(1):11-20. [crossref][PubMed]
16.
Aisen AM, Chenevert TL. MR spectroscopy: clinical perspective. Radiology. 1989;173(3):593-99. [crossref][PubMed]
17.
de Souza AC, Justo GZ, de Araújo DR, Cavagis AD. Defining the molecular basis of tumour metabolism: A continuing challenge since Warburg’s discovery. Cellular Physiology and Biochemistry. 2011;28(5):771-92. [crossref][PubMed]
18.
Golder W. Magnetic resonance spectroscopy in clinical oncology. Oncology Research and Treatment. 2004;27(3):304-09. [crossref][PubMed]
19.
Kerschbaumer J, Pinggera D, Steiger R, Rietzler A, Wöhrer A, Riedmann M, et al. Results of phosphorus magnetic resonance spectroscopy for brain metastases correlate with histopathologic results. World Neurosurgery. 2019;127:e172-78. [crossref][PubMed]
20.
Dudley J, Chu WJ, Fugate EM, Lee JH. Tissue dependent metabolism in the human brain suggested by quantitative phosphorus-31 MRSI. J Spectrosc Dyn. 2014;4:19.
21.
Peter SB, Nandhan VR. 31-Phosphorus magnetic resonance spectroscopy in evaluation of glioma and metastases in 3T MRI. Indian Journal of Radiology and Imaging. 2021;31(04):873-81. [crossref][PubMed]
22.
Kamble RB, Shivashankar R. Energy status and metabolism in intracranial space occupying lesions: a prospective 31p spectroscopic study. Journal of Clinical and Diagnostic Research: JCDR. 2014;8(11):RC05. [crossref][PubMed]
23.
Albers MJ, Krieger MD, Gonzalez-Gomez I, Gilles FH, McComb JG, Nelson Jr MD, et al. Proton-decoupled 31P MRS in untreated pediatric brain tumours. Magnetic Resonance in Medicine: An Official Journal of the International Society for Magnetic Resonance in Medicine. 2005;53(1):22-29. [crossref][PubMed]
24.
Walchhofer LM, Steiger R, Rietzler A, Kerschbaumer J, Freyschlag CF, Stockhammer G, et al. Phosphorous magnetic resonance spectroscopy to detect regional differences of energy and membrane metabolism in naïve glioblastoma multiforme. Cancers. 2021;13(11):2598. [crossref][PubMed]
25.
Hubesch B, Sappey-Marinier D, Roth K, Meyerhoff DJ, Matson GB, Weiner MW. P-31 MR spectroscopy of normal human brain and brain tumours. Radiology. 1990;174(2):401-09. [crossref][PubMed]
26.
Maintz D, Heindel W, Kugel H, Jaeger R, Lackner KJ. Phosphorus-31 MR spectroscopy of normal adult human brain and brain tumours. NMR in Biomedicine: An International Journal Devoted to the Development and Application of Magnetic Resonance In Vivo. 2002;15(1):18-27. [crossref][PubMed]
27.
Hsu PP, Sabatini DM. Cancer cell metabolism: Warburg and beyond. Cell. 2008;134(5):703-07. [crossref][PubMed]
28.
Marie SK, Shinjo SM. Metabolism and brain cancer. Clinics. 2011;66:33-43. [crossref][PubMed]
29.
Delikatny EJ, Chawla S, Leung DJ, Poptani H. MR-visible lipids and the tumour microenvironment. NMR in Biomedicine. 2011;24(6):592-611. [crossref][PubMed]
30.
Puri BK, Treasaden IH. The use of 31-Phosphorus magnetic resonance spectroscopy to study brain cell membrane motion-restricted phospholipids. Neuroimaging–Methods. 2012:205.
31.
Smith SR, Martin PA, Edwards RH. Tumour pH and response to chemotherapy: an in vivo 31P magnetic resonance spectroscopy study in non-Hodgkin’s lymphoma. The British Journal of Radiology. 1991;64(766):923-28. [crossref][PubMed]
32.
Podo F. Tumour phospholipid metabolism. NMR in Biomedicine: An International Journal Devoted to the Development and Application of Magnetic Resonance In Vivo. 1999;12(7):413-39. 3.0.CO;2-U>[crossref]
33.
Solivera J, Cerdan S, Pascual JM, Barrios L, Roda JM. Assessment of 31P-NMR analysis of phospholipid profiles for potential differential diagnosis of human cerebral tumours. NMR in Biomedicine: An International Journal Devoted to the Development and Application of Magnetic Resonance In vivo. 2009;22(6):663-74. [crossref][PubMed]
34.
Andrade CS, Otaduy CG, Park EJ, Leite CC. Phosphorus-31 MR spectroscopy of the human brain: Technical aspects and biomedical applications. International Journal of Current Research and Review. 2014;6(9):41.
35.
Olah J, Klivenyi P, Gardian G, Vécsei L, Orosz F, Kovacs GG, et al. Increased glucose metabolism and ATP level in brain tissue of Huntington’s disease transgenic mice. The FEBS journal. 2008;275(19):4740-55. [crossref][PubMed]
36.
Arnold DL, Shoubridge EA, Feindel W, Villemure JG. Metabolic changes in cerebral gliomas within hours of treatment with intra-arterial BCNU demonstrated by phosphorus magnetic resonance spectroscopy. Canadian Journal of Neurological Sciences. 1987;14(4):570-75.

DOI and Others

DOI: 10.7860/JCDR/2025/67394.20491

Date of Submission: Sep 05, 2023
Date of Peer Review: Dec 07, 2023
Date of Acceptance: Oct 10, 2024
Date of Publishing: Jan 01, 2025

AUTHOR DECLARATION:
• Financial or Other Competing Interests: None
• Was Ethics Committee Approval obtained for this study? Yes
• Was informed consent obtained from the subjects involved in the study? Yes
• For any images presented appropriate consent has been obtained from the subjects. Yes

PLAGIARISM CHECKING METHODS:
• Plagiarism X-checker: Sep 11, 2023
• Manual Googling: Oct 06, 2024
• iThenticate Software: Oct 08, 2024 (8%)

ETYMOLOGY: Author Origin

EMENDATIONS: 7

JCDR is now Monthly and more widely Indexed .
  • Emerging Sources Citation Index (Web of Science, thomsonreuters)
  • Index Copernicus ICV 2017: 134.54
  • Academic Search Complete Database
  • Directory of Open Access Journals (DOAJ)
  • Embase
  • EBSCOhost
  • Google Scholar
  • HINARI Access to Research in Health Programme
  • Indian Science Abstracts (ISA)
  • Journal seek Database
  • Google
  • Popline (reproductive health literature)
  • www.omnimedicalsearch.com