Magnetic Resonance Imaging Research Papers (original) (raw)

Mitochondrial DNA depletion syndromes (MDSs) form a group of autosomal recessive disorders characterized by profoundly decreased mitochondrial DNA copy numbers in affected tissues. Three main clinical presentations are known: myopathic,... more

Mitochondrial DNA depletion syndromes (MDSs) form a group of autosomal recessive disorders characterized by profoundly decreased mitochondrial DNA copy numbers in affected tissues. Three main clinical presentations are known: myopathic, encephalomyopathic and hepatocerebral. The first is associated with mutations in thymidine kinase 2 (TK2) and p53-induced ribonucleotide reductase B subunit (RRM2B); the second with mutations in succinate synthase A (SUCLA2) and B (SUCLG1); the third with mutations in Twinkle (PEO1), pol-γA (POLG1), deoxyguanosine kinase (DGUOK) and MPV17 (MPV17). In this work, we review the MDS-associated phenotypes and present our own experience of 32 MDS patients, with the aim of defining the mutation frequency of the known genes, the clinical spectrum of the diseases, and the genotype–phenotype correlations. Five of our patients carried previously unreported mutations in one of the eight MDS genes.

In this fMRI study we investigated functional connectivity between components of the mentalising system during a social emotion task, using psychophysiological interaction (PPI) analysis. Ten adults (22–32 years) and 18 adolescents (11–18... more

In this fMRI study we investigated functional connectivity between components of the mentalising system during a social emotion task, using psychophysiological interaction (PPI) analysis. Ten adults (22–32 years) and 18 adolescents (11–18 years) were scanned while thinking about scenarios in which a social or a basic emotion would be experienced. Unlike basic emotions (such as disgust and fear), social emotions (such as embarrassment and guilt) require the representation of another’s mental states. In both adults and adolescents, an anterior rostral region of medial prefrontal cortex (arMPFC) involved in mentalising showed greater connectivity with the posterior superior temporal sulcus (pSTS) bordering on the temporo-parietal junction (TPJ) and with anterior temporal cortex (ATC) during social than during basic emotion. This result provides novel evidence that components of the mentalising system interact functionally during a social emotion task. Furthermore, functional connectivity differed between adolescence and adulthood. The adolescent group showed stronger connectivity between arMPFC and pSTS/TPJ during social relative to basic emotion than did the adult group, suggestive of developmental changes in functional integration within the mentalising system.

Diagnostic workup of scrotal lesions should begin with a complete clinical history and physical examination, including analysis of risk factors such as family history of testicular cancer, personal history of tumor in the contralateral... more

Diagnostic workup of scrotal lesions should begin with a complete clinical history and physical examination, including analysis of risk factors such as family history of testicular cancer, personal history of tumor in the contralateral testis, and cryptorchidism, followed by imaging. Scrotal ultrasonography (US) with a combination of gray-scale and color Doppler techniques has been the first-line imaging modality for evaluation of testicular and extratesticular lesions because of its low cost, wide availability, and high diagnostic accuracy. However, US has limitations related to operator dependence, the relatively small field of view, and lack of tissue characterization. Magnetic resonance (MR) imaging, because of its superior soft-tissue contrast and multiplanar capabilities, is increasingly being used as a supplemental diagnostic problem-solving tool in cases where scrotal US findings are inconclusive or nondiagnostic. In addition to morphology, lesion location, and tissue charac...

This study was performed with the aim of determining the diagnostic profile of newborns with hypotonia and of analyzing the usefulness of different procedures in the diagnostic process. One hundred thirty-eight hypotonic newborns were... more

This study was performed with the aim of determining the diagnostic profile of newborns with hypotonia and of analyzing the usefulness of different procedures in the diagnostic process. One hundred thirty-eight hypotonic newborns were identified through the search of hospital records in a 10-year period: 121 (88%) had central hypotonia and 13 (9%) had peripheral hypotonia, whereas 4 (3%) remained unclassified. Analysis of the contribution of clinical data and results of investigations led to the construction of an algorithm, by which all cases in the group were diagnosed. Step 1, which included clinical data and results of examinations, solved 50% of all diagnosed cases. Neuroimaging techniques made up step 2 and contributed to the diagnosis in 13%. Step 3 was accomplished by a search through Oxford Medical Databases, which yielded the final diagnosis in 9%, whereas karyotyping and fluorescent in situ hybridization for Prader-Willi syndrome comprised step 4 and contributed to the di...

The purpose of this study was to evaluate the efficiency of biologic augmentation of rotator cuff repair with iliac crest bone marrow-derived mesenchymal stem cells (MSCs). The prevalence of healing and prevention of re-tears were... more

The purpose of this study was to evaluate the efficiency of biologic augmentation of rotator cuff repair with iliac crest bone marrow-derived mesenchymal stem cells (MSCs). The prevalence of healing and prevention of re-tears were correlated with the number of MSCs received at the tendon-to-bone interface. Forty-five patients in the study group received concentrated bone marrow-derived MSCs as an adjunct to single-row rotator cuff repair at the time of arthroscopy. The average number of MSCs returned to the patient was 51,000 ± 25,000. Outcomes of patients receiving MSCs during their repair were compared to those of a matched control group of 45 patients who did not receive MSCs. All patients underwent imaging studies of the shoulder with iterative ultrasound performed every month from the first postoperative month to the 24th month. The rotator cuff healing or re-tear was confirmed with MRI postoperatively at three and six months, one and two years and at the most recent follow up ...

GRANT SUPPORT This project was funded by the Research Council of Norway. BACKGROUND Oxygen uptake through the gastrointestinal tract after oral administration of oxygenated water in humans is not well studied and is debated in the... more

GRANT SUPPORT This project was funded by the Research Council of Norway. BACKGROUND Oxygen uptake through the gastrointestinal tract after oral administration of oxygenated water in humans is not well studied and is debated in the literature. Due to the paramagnetic properties of oxygen and deoxyhemoglobin, MRI as a technique might be able to detect changes in relaxometry values caused by increased oxygen levels in the blood. PURPOSE To assess whether oxygen dissolved in water is absorbed from the gastrointestinal tract and transported into the bloodstream after oral administration. STUDY TYPE A randomized, double-blinded, placebo-controlled crossover trial. POPULATION/SUBJECTS Thirty healthy male volunteers age 20-35. FIELD STRENGTH/SEQUENCE 3T/Modified Look-Locker inversion recovery (MOLLI) T1 -mapping and multi fast field echo (mFFE) T2 *-mapping. ASSESSMENT Each volunteer was scanned in two separate sessions. T1 and T2 * maps were acquired repeatedly covering the hepatic portal ...

Hypoxic-ischemic encephalopathy (HIE) occurs in 1 to 8 per 1000 live births in developed countries. Historically, the clinician has had little to offer neonates with HIE other than systemic supportive care. Recently, the neuroprotective... more

Hypoxic-ischemic encephalopathy (HIE) occurs in 1 to 8 per 1000 live births in developed countries. Historically, the clinician has had little to offer neonates with HIE other than systemic supportive care. Recently, the neuroprotective therapy of hypothermia has emerged as the standard of care, and other complementary therapies are rapidly transitioning from the basic science to clinical care. To examine the pathophysiology of HIE and the state of the art for the clinical care of neonates with HIE. We performed a literature review using the PubMed database. Results focused on reviews and articles published from January 1, 2004, through December 31, 2014. Articles published earlier than 2004 were included when appropriate for historical perspective. Our review emphasized evidence-based management practices for the clinician. A total of 102 articles for critical review were selected based on their relevance to the incidence of HIE, pathophysiology, neuroimaging, placental pathology, ...

Traumatic brain injury (TBI) has been recently recognized as a leading cause of pituitary dysfunction. Current data clearly demonstrated that sports related head trauma due to boxing, kickboxing, and soccer might results in pituitary... more

Traumatic brain injury (TBI) has been recently recognized as a leading cause of pituitary dysfunction. Current data clearly demonstrated that sports related head trauma due to boxing, kickboxing, and soccer might results in pituitary hormone deficiencies, isolated growth hormone (GH) deficiency in particular. In the present report physiologic dose GH replacement therapy (GHRT) was performed in two GH deficient retired amateur boxers for the first time. The boxers received recombinant GH for 6 months. After 6 months of GHRT there were substantial improvements, but not complete normalization, in the body composition parameters, lipid profiles and quality of life scores in both boxers. These preliminary results suggest that GHRT may have beneficial effects in retired boxers with severe isolated GH deficiency due to sports related head trauma. But more data with higher number of boxers and longer GHRT duration are warranted.

Traumatic brain injury (TBI) is one of the leading causes of morbidity and mortality among people worldwide. It commonly results from high-velocity vehicle accidents, falls from heights, assaults and sport injuries. TBI can be classified... more

Traumatic brain injury (TBI) is one of the leading causes of morbidity and mortality among people worldwide. It commonly results from high-velocity vehicle accidents, falls from heights, assaults and sport injuries. TBI can be classified as mild, moderate and severe depending on the score on the Glasgow Coma Scale (GCS). In terms of neurosurgical emergencies, accurate imaging diagnosis is essential. In these cases, computed tomography (CT) is the most widely used and readily available neuroimaging modality. Mild TBI (mTBI) presents approximately 90% of all head injuries. A great number of mTBIs are believed to cause only transient functional impairments to the brain due to the lack of sufficient radiological evidence on conventional CT and magnetic resonance imaging (MRI) scans. Generally, the diagnosis is based on the data obtained from the history and the neurological status. In some cases, categorized as ―complicated mTBI‖, CT may present with visible focal contusions consistent ...