Advances in Molecular Imaging
ISSN / EISSN : 2161-6728 / 2161-6752
Current Publisher: Scientific Research Publishing, Inc. (10.4236)
Total articles ≅ 55
Latest articles in this journal
Advances in Molecular Imaging, Volume 11, pp 1-15; doi:10.4236/ami.2021.111001
Therapies based on stem cell transplants offer significant potential in the field of regenerative medicine. Monitoring the fate of the transplanted stem cells in a timely manner is considered one of the main limitations for long-standing success of stem cell transplants. Imaging methods that visualize and track stem cells in vivo non-invasively in real time are helpful towards the development of successful cell transplantation techniques. Novel molecular imaging methods which are non-invasive particularly such as MRI have been of great recent interest. Hence, mouse models which are of clinical relevance have been studied by injecting contrast agents used for labelling cells such as super-paramagnetic iron-oxide (SPIO) nanoparticles for cellular imaging. The MR techniques which can be used to generate positive contrast images have been of much relevance recently for tracking of the labelled cells. Particularly when the off-resonance region in the vicinity of the labeled cells is selectively excited while suppressing the signals from the non-labeled regions by the method of spectral dephasing. Thus, tracking of magnetically labelled cells employing positive contrast in vivo MR imaging methods in a burn mouse model in a non-invasive way has been the scope of this study. The consequences have direct implications for monitoring labeled stem cells at some stage in wound healing. We suggest that our approach can be used in clinical trials in molecular and regenerative medicine.
Advances in Molecular Imaging, Volume 10, pp 15-29; doi:10.4236/ami.2020.103003
Introduction: 68Ga-PSMA-PET/CT has proven its value in prostate cancer with high positive predictive value for lymph node metastasis and superior detection of distant metastasis. There is growing evidence that 68Ga-PSMA- PET/CT has high sensitivity for detection of tumor lesions in the prostate as well. Studies thus far have mainly been performed in patients prior to prostatectomy. Aim of this study is to evaluate diagnostic accuracy in a mixed population of men with increased risk of prostate cancer and evaluate diagnostic possibilities with respect to extra-capsular extension and seminal vesicle invasion. Methods: The population consisted of a retrospectively included sequential cohort of 69 patients with 68Ga-PSMA-PET/CT and mpMRI available. 68Ga-PSMA-PET/CT was re-evaluated by two readers blinded for mpMRI and clinical information. Likelihood of tumour presence, extra-prostatic extension and seminal vesicle invasion was scored on 5-point Likert scale and localized schematically. Results were compared with mpMRI. Available pathological outcome served as gold standard. SUVmax of index lesions was measured and correlated to index tumor Gleason grade. Results: Clinically significant prostate cancer (Gleason ≥ 3 + 4) was detected in 57 (83%) of 69 patients. Diagnostic accuracy was 89% for PET reader 1, 93% for PET reader 2 and 86% for mpMRI. Lesion concordance of 68Ga-PSMA-PET/CT and mpMRI was 97%. SUVmax of the index lesion correlated to Gleason grade. Sensitivity for extracapsular extension in the prostatectomy group was 62% for PET reader 1, 33% for PET reader 2 and 50% for mpMRI. Specificity was 62% for PET reader 1, 100% for PET reader 2 and 69% for mpMRI. Conclusion: Ga68-PSMA-PET shows high accuracy in the detection of tumor lesions in the prostate. Results on evaluating extra-capsular extension and seminal vesicle invasion are comparable to mpMRI. This study adds to the increasing evidence that 68Ga-PSMA-PET/CT is imperative in detection of prostate cancer prior to biopsy.
Advances in Molecular Imaging, Volume 10, pp 7-13; doi:10.4236/ami.2020.102002
We report herein a case of a 40-year-old male patient with chronic renal failure presenting a severe hyperparathyroidism with an elevation of parathormone level evaluated in nuclear medicine department for MIBI-Technetium-99m parathyroid scintigraphy. The parathyroid scintigraphy revealed the appearance of a preferential fixation of the MIBI-99mTc opposite the lower left pole of the thyroid and opposite the upper part of the right hemi thorax. A subsequent single-photon emission computed tomography-computed tomography focused on the cervico-thoracic region was performed and showed an ectopic parathyroid adenoma associated with an incidental brown tumor mimicking bone and lung metastases. Our case report confirms the usefulness of additional hybrid SPECT-CT imaging in the management of hyperparathyroidism.
Advances in Molecular Imaging, Volume 10, pp 1-5; doi:10.4236/ami.2020.101001
Planar bone Scintigraphy has been frequently used to assess the active or inactive nature of mandibular hypercondylia. We report here the case of a patient whose diagnosis of active mandibular hypercondylia was retained after a complement with SPECT/CT imaging, the planar bone scan being negative. This case confirms the use of SPECT/ CT as the examination of choice for full assessment of mandibular hypercondylia in adults. Using bone Scintigraphy SPECT/CT improves both sensitivity and specificity of diagnosing this condition.
Advances in Molecular Imaging, Volume 10, pp 31-37; doi:10.4236/ami.2020.104004
Background: Research studies made in Cameroon on compliance and relevance in the various areas of imaging, show the failure to comply with administrative and clinical criteria. These research studies led to recommendations meant for result amelioration. However, the orthopantomogram (OPT) field remains less studied in that regard in Cameroon. Aim: Evaluate the relevance and compliance of examination requests for panoramic dental radiography. Setting and Design: It is a descriptive cross-sectional study with a consecutive sample of dental panoramic requests identified during the study period in 4 radiology centres of Yaoundé. Material and Methods: Variables studied here were the validity criteria of imaging examination. Request: Five of which are of administrative order (date of the request, requesting department, patient’s identity, patient’s age, applicant’s identity) and three of clinical order (anatomic region, reason for the examination and the purpose of the examination). Statistical Analysis: Chi-squared test was used with confidence interval of 95%. Results: Patient’s identity (name) was the criteria carrying the highest information (98.9%), followed by the name of the applicant physician (91.6%). Out of 179 requests analysed, 8.6% had complete information. 46.4% of requests had no indications. Dental surgeon was the top prescriber with a total of 112 (62.6%). Conclusion: The quality of dental panoramic requests was not optimal in Yaounde, with lack of precision mostly noted at the level of clinical criteria.
Advances in Molecular Imaging, Volume 9, pp 6-18; doi:10.4236/ami.2019.91002
Advances in Molecular Imaging, Volume 9, pp 43-52; doi:10.4236/ami.2019.93004
Background: Systematic chest X-ray is the most prescribed examination by occupational physicians during periodic medical check-ups in our context, unlike in most countries where this practice has been discontinued. Objective: The objective was to determine the diagnostic yield and cost-effectiveness of chest radiography during periodic medical check-ups of workers in Ngaoundere. Materials and Methods: A cross-sectional and descriptive study was carried out in Ngaoundere Regional Hospital from January to December 2018, concerning all persons coming to perform a systematic chest X-ray in the context of the periodic medical check-up having been consented to participate in the study. Posteroanterior (PA) chest radiographs were obtained from all workers during this periodic medical check-up. The variables studied were: age, sex, clinical manifestations, antecedents, job type, cost, and chest X-ray results. Statistical analysis was performed using the Sphinx Plus2-Lexica-V5 Edition software. Results: 753 workers were selected for this study, of whom 88.04% were men and 11.96% were women, a sex ratio H/F is of 7.4, the average age was 39 ± 7.89 years with extremes of 24 and 56 years, the most frequent job type was the administration (38.37%), the storekeepers (17.92) and the drivers (15.27%), most of them were asymptomatic (97.47%), some had cough (2.52%), chest pain (2.12%), dyspnea (0.26%) and fever (0.13%). History was dominated by lung infection (2.39%), pleurisy (1.06%) and tuberculosis (0.79%). 7.43% of workers occasionally smoked tobacco and consumed alcohol. 41 cases of pathologies (5.44%) were found on the chest X-ray, including 1 case (0.13%) of evolutionary pathology, 40 cases (5.31%) of sequelae pathologies. When the results of the chest X-ray are compared with the clinical signs and the pathological history of the workers, it is found that the only case with evolutionary abnormalities on the chest X-ray showed clinical signs and that the other cases with sequelae abnormalities had either clinical signs or antecedents related to these abnormalities. The cost of a chest X-ray at the time of our study was 5,000 FCFA ($8.59), for a total of 3,765,000 FCFA ($6473.74) for all the X-rays performed. Conclusion: In view of the low rate of abnormalities on the chest X-ray and the sequelae nature of the pathologies, it can be said that the routine X-ray of the chest during the periodic medical check-ups has a low diagnostic yield and a low cost-effectiveness ratio and is not profitable. It should be non-systematic and case-by-case based on the clinical context and background of workers.
Advances in Molecular Imaging, Volume 9, pp 1-5; doi:10.4236/ami.2019.91001
Sphenoid sinuses are carved into the body of the sphenoid bone. They are probably the most variably pneumatized structures of the skull. They begin their pneumatization at the age of three and finished at adolescence. Several anatomic variants of sphenoid sinuses have been described in the literature. The agenesis of sphenoid sinuses in adults is very rarely found. We report two incidental cases of sphenoid sinuses agenesis discovered on CT scan in Benin, West Africa.
Advances in Molecular Imaging, Volume 9, pp 19-42; doi:10.4236/ami.2019.92003
Background: The unavoidable links between the benefits of conventional systemic treatment of cancer and the side effects such as lymphopenia. Objective: To analyze this phenomenon in view of the newly discovered trophic function of circulating hematopoietic stem cells (HSC) and their lymphocyte descendants. Method: We used population statistics and recent current research involving natural aging and preliminary aging with cancer, its cytotoxic therapy, eclampsia at pregnancy, and radiation hormesis. Results: In contrast to immune-defense interpretations of these health conditions, the trophic influence of HSC and morphogenic lymphocytes on natural tissue renewal and regeneration after sublethal injuries eliminates the majority of covered inconsistencies, which are inherent to the dominating idea of cellular immunity. Conclusion: Our examination led to the feeding influence of lymphopoiesis on tumor progression, an indirect mechanism of tumor growth control by systemic therapy via either destruction of trophic cells, or by competitive distraction from malignant tissue via reparation of sublethal injuries in normal tissues. Analyses also involved similarities of the mechanisms of systemic chemotherapy and total body/half body radiotherapy in low doses, as well as the futility of the theoretical opposition of the radiation hormesis phenomenon to the linear non-threshold model, dominant in radiobiology.
Advances in Molecular Imaging, Volume 9, pp 53-59; doi:10.4236/ami.2019.94008
One of the commercially available capillary-based microfluidic synthesizers is Advion NanoTek Microfluidic Synthesis System and is currently being used across the globe. The goal of this study is to demonstrate the system capability to perform the synthesis of two compounds sequentially without cleaning the equipment between the syntheses. We have chosen to prepare two key radiotracers [F-18]FLT and [F-18]FMISO. The basic microfluidic flow chemistry module was reconfigured to allow the hydrolysis of the second tracer in a vial using reactor 1 as a heat source and the system was integrated to semi-preparative high-performance liquid chromatography with a column selector and solvent selector. The decay corrected radio chemical yields of [18F]FLT and [18F]FMISO were found to be 28.5% and 38.6% respectively. The specific activity was determined to be >2 Ci/μmol.