Journal of oral and facial pain and headache, Jun 1, 2014
To examine (1) the occurrence of magnetic resonance imaging (MRI) signal changes in the painful r... more To examine (1) the occurrence of magnetic resonance imaging (MRI) signal changes in the painful regions of patients with atypical odontalgia (AO) and (2) the correlation of such findings to periapical bone defects detected with a comprehensive radiographic examination including cone beam computed tomography (CBCT). Methods: A total of 20 patients (mean age 52 years, range 34 to 65) diagnosed with AO participated. Mean pain intensity (± standard deviation) was 5.6 ± 1.8 on a 0-10 numerical rating scale, and mean pain duration was 4.3 ± 5.2 years. The inclusion criterion was chronic pain (> 6 months) located in a region with no clear pathologic cause identified clinically or in periapical radiographs. In addition to a clinical examination and a self-report questionnaire, the assessments included radiographic examinations (panoramic, periapical, and CBCT images), and an MRI examination. Changes in MRI signal in the painful region were recorded. Spearman's rank correlation between radiographic and MRI findings was calculated. Results: Eight of the patients (40%) had MRI signal changes in the pain region. The correlation to radiographic periapical radiolucencies was 0.526 (P = .003). Of the eight teeth displaying changes in MRI signal, six showed periapical radiolucency in the radiographs. Conclusion: MRI examination revealed no changes in the painful region in a majority of patients with AO, suggesting that inflammation was not present. MRI findings were significantly correlated to radiographic findings.
The aim of this study was to analyze the MRI findings and assess the prevalence of different asso... more The aim of this study was to analyze the MRI findings and assess the prevalence of different associated structural abnormalities in children with scoliosis and to determine if the age of onset is a possible indicator of intraspinal pathology. This is a retrospective analysis of 663 consecutive MR examinations (319 patients). Thirteen patients with known intraspinal tumors were excluded and a total of 306 patients aged 2–18 years with scoliosis were subjected for analysis. The scoliosis was regarded as idiopathic in 62% of patients. Among the remaining 38% the most commonly seen abnormality was syrinx and Chiari malformations. There was no statistically significant difference in the occurrence of syrinx only or syrinx associated with Chiari I malformation in patients younger than ten years and those older than ten years. MRI examination is an essential part of the work up of scoliosis in the pediatric population especially before any corrective surgery. This study and a review of the...
The aim of this study was to analyze the added utility of contrast administration for spine MRI i... more The aim of this study was to analyze the added utility of contrast administration for spine MRI in children with scoliosis. A retrospective review of 663 consecutive contrast-enhanced spine MRI performed in 319 patients as part of the work up of scoliosis in children 2–18 years with clinically suspected or known scoliosis over a seven year period. Those patients with known tumors (13 patients) being evaluated for scoliosis were excluded from the study. In 306 patients with scoliosis and no history of tumor pathologic contrast enhancement was seen in seven (2%) patients. Lack of enhancement helped to characterize benign lesions in 31 (10%) of the patients. Although MRI is often recommended to exclude intraspinal pathology in pediatric patients with scoliosis, the need for contrast enhanced imaging is very limited and contrast medium should not be administered unless questionable pathology is detected on noncontrast MR spine imaging.
The aim of this study was to evaluate the added utility of gadolinium administration in the magne... more The aim of this study was to evaluate the added utility of gadolinium administration in the magnetic resonance imaging evaluation of developmental delay in children less than 2 years of age. A computerized retrospective study identified all brain magnetic resonance imaging examinations using gadolinium performed at our institution from 1995-2002 for children under the age of 2 years. Review of the clinical records and magnetic resonance imaging reports identified 170 brain magnetic resonance imaging examinations that were performed for developmental delay. Magnetic resonance imaging studies with enhancing lesions were reviewed by two staff neuroradiologists and two radiology residents. Contrast administration was rated as essential, helpful, or not helpful for each study. In the 107 patients in whom developmental delay was the primary concern, there were no cases in which the findings would have been missed without gadolinium administration. In the 63 patients in whom developmental delay was a secondary concern, there were several cases (11%) where contrast was helpful but not essential in reaching a radiologic diagnosis. In conclusion, intravenous gadolinium has an extremely low yield in children under the age of 2 where developmental delay is the primary concern. In young children for whom developmental delay is a secondary concern, we advocate the use of gadolinium particularly where tumor or infection is clinically suspected.
Our objective was to review the frequency and pattern of signal abnormalities seen on conventiona... more Our objective was to review the frequency and pattern of signal abnormalities seen on conventional MRI in patients with suspected neuropsychiatric systemic lupus erythematosus (NP-SLE). We reviewed 116 MRI examinations of the brain performed on 85 patients with SLE, (81 women, four men, aged 21-78 years, mean 40.6 years) presenting with neurological disturbances. MRI was normal or nearly normal in 34%. In 60% high-signal lesions were observed on T2-weighted images, frequently in the frontal and parietal subcortical white matter. Infarct-like lesions involving gray and white matter were demonstrated in 21 of cases. Areas of restricted diffusion were seen in 12 of the 67 patients who underwent diffusion-weighted imaging. Other abnormalities included loss of brain volume, hemorrhage, meningeal enhancement, and bilateral high signal in occipital white-matter. The MRI findings alone did not allow us to distinguish between thromboembolic and inflammatory events in many patients. Some patients with normal MRI improved clinically while on immunosuppressive therapy. More sensitive and/or specific imaging methods, such as spectroscopy and perfusion-weighted imaging, should be investigated in these subgroups of patients with suspected NP-SLE.
We review the theoretical background to diffusion tensor imaging (DTI) and some of its commoner c... more We review the theoretical background to diffusion tensor imaging (DTI) and some of its commoner clinical applications, such as cerebral ischemia, brain maturation and traumatic brain injury. We also review its potential use in diseases such as epilepsy, multiple sclerosis, and Alzheimer's disease. The value of DTI in the investigation of brain tumors and metabolic disorders is assessed.
A parallel, double-blind, randomized study comparing iohexol and metrizamide--both 180 mg l/ml--i... more A parallel, double-blind, randomized study comparing iohexol and metrizamide--both 180 mg l/ml--in lumbar myelography was carried out in 60 consecutive patients. Eight to 15 ml of contrast medium were administered with the upper level at the middle thoracic column. A detailed neurologic examination was performed before and 24 hr after myelography. EEG recordings--evaluated visually and with fast Fourier transformation analysis--and somatosensory evoked responses were registered before, 6 hr after, and 24 hr after myelography. All patients were observed for adverse reactions for 24-48 hr. Iohexol did not produce any epileptiform activity but epileptiform activity was detected in five patients receiving metrizamide. Iohexol produced significantly less frequent and less severe EEG changes than did metrizamide both at visual evaluation (p less than .0025) and at fast Fourier transformation analysis (p less than .04). No significant changes occurred in the early components of the somatos...
An attempt was made to assess the usefulness of using an animal model to predict the neural toler... more An attempt was made to assess the usefulness of using an animal model to predict the neural tolerability in man of iodinated contrast media (CM) in general, and of the new nonionic dimer iodixanol in particular. For this purpose, the results from 6 animal experiments evaluating excitative and depressive effects of subarachnoidally injected CM in nonanesthetized rabbits were compared with the results from 22 randomized double-blind clinical trials dealing with post-myelographic adverse reactions. Comparisons were made as regards the nonionic monomers metrizamide, iohexol, and iopamidol, and the dimer iotrolan. The results seem to justify the conclusion that the convulsive effects of CM can be reliably predicted from animal experiments. The animal model cannot be used to predict specific types of nonconvulsive adverse reactions in man, but reflects well the differences in frequencies of minor reactions following clinical myelography with different nonionic CM. In general, the neural tolerability of iodixanol may be expected to be better than that of the nonionic monomers and approximately equal to that of iotrolan.
Measurements of skin dose, integrated skin dose area, and integral dose in combined conventional ... more Measurements of skin dose, integrated skin dose area, and integral dose in combined conventional and magnification renal angiography using lanthanoxibromide screens MR 600 and carbon fibre plate in filmchangertop have been made. The mean skin dose in magnification technique was 0.56 rad./film with focus-skin distance of 35 cm, FFD 1 m, 85-90 kV and sagittal diameter of abdomen of 20 cm. The combination of angiographic technique with and without magnification and the use of a high-sensitivity receiving unit makes it possible to keep the total skin dose per investigation (8.5 rad.) within the limits accepted in conventional abdominal angiography.
Primary central nervous system lymphoma (PCNSL), glioblastoma multiforme (GBM) and metastases may... more Primary central nervous system lymphoma (PCNSL), glioblastoma multiforme (GBM) and metastases may be difficult to differentiate based on conventional imaging alone. The aim of this study was to investigate the value of perfusion weighted imaging (PWI) in differentiating homogeneously enhancing PCNSL from homogeneously enhancing GBM and metastases. Seven consecutive patients presenting with homogeneously enhancing intraaxial tumors on MRI were retrospectively analyzed. All seven patients (three immunocompetent patients with PCNSL, three with GBM, and one with cerebral metastases) were examined with identical MR-sequences including PWI. The relative regional Cerebral Blood Volume (rrCBV) and the rrCBV ratio (rrCBVratio) were calculated. In lymphomas rrCBVratio was 0.93 ± 0.42 (mean ± SD) compared with 7.93 ± 1.44 in GBM and metastases. All lymphomas had rrCBVratio < 1.43 while all GBM and metastases had rrCBVratio > 1.43 (Fischer exact test; p < 0.001). PWI may be a valuable ...
To examine (1) the occurrence of magnetic resonance imaging (MRI) signal changes in the painful r... more To examine (1) the occurrence of magnetic resonance imaging (MRI) signal changes in the painful regions of patients with atypical odontalgia (AO) and (2) the correlation of such findings to periapical bone defects detected with a comprehensive radiographic examination including cone beam computed tomography (CBCT). A total of 20 patients (mean age 52 years, range 34 to 65) diagnosed with AO participated. Mean pain intensity (± standard deviation) was 5.6 ± 1.8 on a 0-10 numerical rating scale, and mean pain duration was 4.3 ± 5.2 years. The inclusion criterion was chronic pain (> 6 months) located in a region with no clear pathologic cause identified clinically or in periapical radiographs. In addition to a clinical examination and a self-report questionnaire, the assessments included radiographic examinations (panoramic, periapical, and CBCT images), and an MRI examination. Changes in MRI signal in the painful region were recorded. Spearman's rank correlation between radiogr...
Journal of oral and facial pain and headache, Jun 1, 2014
To examine (1) the occurrence of magnetic resonance imaging (MRI) signal changes in the painful r... more To examine (1) the occurrence of magnetic resonance imaging (MRI) signal changes in the painful regions of patients with atypical odontalgia (AO) and (2) the correlation of such findings to periapical bone defects detected with a comprehensive radiographic examination including cone beam computed tomography (CBCT). Methods: A total of 20 patients (mean age 52 years, range 34 to 65) diagnosed with AO participated. Mean pain intensity (± standard deviation) was 5.6 ± 1.8 on a 0-10 numerical rating scale, and mean pain duration was 4.3 ± 5.2 years. The inclusion criterion was chronic pain (> 6 months) located in a region with no clear pathologic cause identified clinically or in periapical radiographs. In addition to a clinical examination and a self-report questionnaire, the assessments included radiographic examinations (panoramic, periapical, and CBCT images), and an MRI examination. Changes in MRI signal in the painful region were recorded. Spearman's rank correlation between radiographic and MRI findings was calculated. Results: Eight of the patients (40%) had MRI signal changes in the pain region. The correlation to radiographic periapical radiolucencies was 0.526 (P = .003). Of the eight teeth displaying changes in MRI signal, six showed periapical radiolucency in the radiographs. Conclusion: MRI examination revealed no changes in the painful region in a majority of patients with AO, suggesting that inflammation was not present. MRI findings were significantly correlated to radiographic findings.
The aim of this study was to analyze the MRI findings and assess the prevalence of different asso... more The aim of this study was to analyze the MRI findings and assess the prevalence of different associated structural abnormalities in children with scoliosis and to determine if the age of onset is a possible indicator of intraspinal pathology. This is a retrospective analysis of 663 consecutive MR examinations (319 patients). Thirteen patients with known intraspinal tumors were excluded and a total of 306 patients aged 2–18 years with scoliosis were subjected for analysis. The scoliosis was regarded as idiopathic in 62% of patients. Among the remaining 38% the most commonly seen abnormality was syrinx and Chiari malformations. There was no statistically significant difference in the occurrence of syrinx only or syrinx associated with Chiari I malformation in patients younger than ten years and those older than ten years. MRI examination is an essential part of the work up of scoliosis in the pediatric population especially before any corrective surgery. This study and a review of the...
The aim of this study was to analyze the added utility of contrast administration for spine MRI i... more The aim of this study was to analyze the added utility of contrast administration for spine MRI in children with scoliosis. A retrospective review of 663 consecutive contrast-enhanced spine MRI performed in 319 patients as part of the work up of scoliosis in children 2–18 years with clinically suspected or known scoliosis over a seven year period. Those patients with known tumors (13 patients) being evaluated for scoliosis were excluded from the study. In 306 patients with scoliosis and no history of tumor pathologic contrast enhancement was seen in seven (2%) patients. Lack of enhancement helped to characterize benign lesions in 31 (10%) of the patients. Although MRI is often recommended to exclude intraspinal pathology in pediatric patients with scoliosis, the need for contrast enhanced imaging is very limited and contrast medium should not be administered unless questionable pathology is detected on noncontrast MR spine imaging.
The aim of this study was to evaluate the added utility of gadolinium administration in the magne... more The aim of this study was to evaluate the added utility of gadolinium administration in the magnetic resonance imaging evaluation of developmental delay in children less than 2 years of age. A computerized retrospective study identified all brain magnetic resonance imaging examinations using gadolinium performed at our institution from 1995-2002 for children under the age of 2 years. Review of the clinical records and magnetic resonance imaging reports identified 170 brain magnetic resonance imaging examinations that were performed for developmental delay. Magnetic resonance imaging studies with enhancing lesions were reviewed by two staff neuroradiologists and two radiology residents. Contrast administration was rated as essential, helpful, or not helpful for each study. In the 107 patients in whom developmental delay was the primary concern, there were no cases in which the findings would have been missed without gadolinium administration. In the 63 patients in whom developmental delay was a secondary concern, there were several cases (11%) where contrast was helpful but not essential in reaching a radiologic diagnosis. In conclusion, intravenous gadolinium has an extremely low yield in children under the age of 2 where developmental delay is the primary concern. In young children for whom developmental delay is a secondary concern, we advocate the use of gadolinium particularly where tumor or infection is clinically suspected.
Our objective was to review the frequency and pattern of signal abnormalities seen on conventiona... more Our objective was to review the frequency and pattern of signal abnormalities seen on conventional MRI in patients with suspected neuropsychiatric systemic lupus erythematosus (NP-SLE). We reviewed 116 MRI examinations of the brain performed on 85 patients with SLE, (81 women, four men, aged 21-78 years, mean 40.6 years) presenting with neurological disturbances. MRI was normal or nearly normal in 34%. In 60% high-signal lesions were observed on T2-weighted images, frequently in the frontal and parietal subcortical white matter. Infarct-like lesions involving gray and white matter were demonstrated in 21 of cases. Areas of restricted diffusion were seen in 12 of the 67 patients who underwent diffusion-weighted imaging. Other abnormalities included loss of brain volume, hemorrhage, meningeal enhancement, and bilateral high signal in occipital white-matter. The MRI findings alone did not allow us to distinguish between thromboembolic and inflammatory events in many patients. Some patients with normal MRI improved clinically while on immunosuppressive therapy. More sensitive and/or specific imaging methods, such as spectroscopy and perfusion-weighted imaging, should be investigated in these subgroups of patients with suspected NP-SLE.
We review the theoretical background to diffusion tensor imaging (DTI) and some of its commoner c... more We review the theoretical background to diffusion tensor imaging (DTI) and some of its commoner clinical applications, such as cerebral ischemia, brain maturation and traumatic brain injury. We also review its potential use in diseases such as epilepsy, multiple sclerosis, and Alzheimer's disease. The value of DTI in the investigation of brain tumors and metabolic disorders is assessed.
A parallel, double-blind, randomized study comparing iohexol and metrizamide--both 180 mg l/ml--i... more A parallel, double-blind, randomized study comparing iohexol and metrizamide--both 180 mg l/ml--in lumbar myelography was carried out in 60 consecutive patients. Eight to 15 ml of contrast medium were administered with the upper level at the middle thoracic column. A detailed neurologic examination was performed before and 24 hr after myelography. EEG recordings--evaluated visually and with fast Fourier transformation analysis--and somatosensory evoked responses were registered before, 6 hr after, and 24 hr after myelography. All patients were observed for adverse reactions for 24-48 hr. Iohexol did not produce any epileptiform activity but epileptiform activity was detected in five patients receiving metrizamide. Iohexol produced significantly less frequent and less severe EEG changes than did metrizamide both at visual evaluation (p less than .0025) and at fast Fourier transformation analysis (p less than .04). No significant changes occurred in the early components of the somatos...
An attempt was made to assess the usefulness of using an animal model to predict the neural toler... more An attempt was made to assess the usefulness of using an animal model to predict the neural tolerability in man of iodinated contrast media (CM) in general, and of the new nonionic dimer iodixanol in particular. For this purpose, the results from 6 animal experiments evaluating excitative and depressive effects of subarachnoidally injected CM in nonanesthetized rabbits were compared with the results from 22 randomized double-blind clinical trials dealing with post-myelographic adverse reactions. Comparisons were made as regards the nonionic monomers metrizamide, iohexol, and iopamidol, and the dimer iotrolan. The results seem to justify the conclusion that the convulsive effects of CM can be reliably predicted from animal experiments. The animal model cannot be used to predict specific types of nonconvulsive adverse reactions in man, but reflects well the differences in frequencies of minor reactions following clinical myelography with different nonionic CM. In general, the neural tolerability of iodixanol may be expected to be better than that of the nonionic monomers and approximately equal to that of iotrolan.
Measurements of skin dose, integrated skin dose area, and integral dose in combined conventional ... more Measurements of skin dose, integrated skin dose area, and integral dose in combined conventional and magnification renal angiography using lanthanoxibromide screens MR 600 and carbon fibre plate in filmchangertop have been made. The mean skin dose in magnification technique was 0.56 rad./film with focus-skin distance of 35 cm, FFD 1 m, 85-90 kV and sagittal diameter of abdomen of 20 cm. The combination of angiographic technique with and without magnification and the use of a high-sensitivity receiving unit makes it possible to keep the total skin dose per investigation (8.5 rad.) within the limits accepted in conventional abdominal angiography.
Primary central nervous system lymphoma (PCNSL), glioblastoma multiforme (GBM) and metastases may... more Primary central nervous system lymphoma (PCNSL), glioblastoma multiforme (GBM) and metastases may be difficult to differentiate based on conventional imaging alone. The aim of this study was to investigate the value of perfusion weighted imaging (PWI) in differentiating homogeneously enhancing PCNSL from homogeneously enhancing GBM and metastases. Seven consecutive patients presenting with homogeneously enhancing intraaxial tumors on MRI were retrospectively analyzed. All seven patients (three immunocompetent patients with PCNSL, three with GBM, and one with cerebral metastases) were examined with identical MR-sequences including PWI. The relative regional Cerebral Blood Volume (rrCBV) and the rrCBV ratio (rrCBVratio) were calculated. In lymphomas rrCBVratio was 0.93 ± 0.42 (mean ± SD) compared with 7.93 ± 1.44 in GBM and metastases. All lymphomas had rrCBVratio < 1.43 while all GBM and metastases had rrCBVratio > 1.43 (Fischer exact test; p < 0.001). PWI may be a valuable ...
To examine (1) the occurrence of magnetic resonance imaging (MRI) signal changes in the painful r... more To examine (1) the occurrence of magnetic resonance imaging (MRI) signal changes in the painful regions of patients with atypical odontalgia (AO) and (2) the correlation of such findings to periapical bone defects detected with a comprehensive radiographic examination including cone beam computed tomography (CBCT). A total of 20 patients (mean age 52 years, range 34 to 65) diagnosed with AO participated. Mean pain intensity (± standard deviation) was 5.6 ± 1.8 on a 0-10 numerical rating scale, and mean pain duration was 4.3 ± 5.2 years. The inclusion criterion was chronic pain (> 6 months) located in a region with no clear pathologic cause identified clinically or in periapical radiographs. In addition to a clinical examination and a self-report questionnaire, the assessments included radiographic examinations (panoramic, periapical, and CBCT images), and an MRI examination. Changes in MRI signal in the painful region were recorded. Spearman's rank correlation between radiogr...
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Papers by Pavel Maly