Susan Palasis | Northwestern University (original) (raw)
Papers by Susan Palasis
Diffusion-weighted imaging (DWI) is one of the most powerful imaging tools available to radiologi... more Diffusion-weighted imaging (DWI) is one of the most powerful imaging tools available to radiologists today. DWI of the brain revolutionized neuroimaging when it was introduced in the mid-1990s. Until recently, clinically useful DWI of the spine has not been possible using standard single shot EPI techniques due to susceptibility artifacts and the need for higher spatial resolution. The novel 2D-navigator-corrected readout-segmented EPI sequence known as RESOLVE (REadout Segmentation Of Long Variable Echo trains) can obtain images with higher spatial resolution and reduced distortion of the spine RESOLVE: A Powerful Tool for Imaging the Pediatric Spine
Journal of Pediatric Neuroradiology, 2015
White matter (WM) injury is increasingly recognized as central to the impact on the quality of li... more White matter (WM) injury is increasingly recognized as central to the impact on the quality of life of patients with all severity levels of traumatic brain injury. It can be the determinant of death or persistent disability. This article reviews the characteristics of the developing brain in relation to trauma, the primary and secondary phases of WM injury, and advanced magnetic resonance techniques in the evaluation of brain trauma. Special emphasis is placed on non-accidental trauma and sports-related WM injury, respectively.
Pediatric Radiology, 2010
The Lancet Child & Adolescent Health
Journal of the American College of Radiology
Journal of Child Neurology
Purpose: Tuberous sclerosis complex is a multisystem genetic disorder characterized by multiorgan... more Purpose: Tuberous sclerosis complex is a multisystem genetic disorder characterized by multiorgan hamartomas, seizures, and developmental delay. Current consensus recommendations for tuberous sclerosis complex include brain magnetic resonance imaging (MRI) without and with contrast every 1 to 3 years until age 25 years for subependymal giant cell astrocytoma screening, and more often in patients with known subependymal giant cell astrocytoma. Recent reports in the literature regarding gadolinium deposition have prompted us to investigate the added value of intravenous contrast in this setting. Materials and Methods: Thirty-nine MRI examinations from 12 tuberous sclerosis complex patients with known subependymal giant cell astrocytoma were retrospectively reviewed for all caudothalamic groove lesions larger than 1 cm. Lesions were measured in 2 planes on both noncontrast and contrast-enhanced axial 3-dimensional (3D) T1-weighted imaging in a randomized fashion by 2 attending pediatri...
Journal of the American College of Radiology
Scoliosis is frequently encountered in childhood, with prevalence of 2%. The majority is idiopath... more Scoliosis is frequently encountered in childhood, with prevalence of 2%. The majority is idiopathic, without vertebral segmentation anomaly, dysraphism, neuromuscular abnormality, skeletal dysplasia, tumor, or infection. As a complement to clinical assessment, radiography is the primary imaging modality used to classify scoliosis and subsequently monitor its progression and response to treatment. MRI is utilized selectively to assess for neural axis abnormalities in those at higher risk, including those with congenital scoliosis, early onset idiopathic scoliosis, and adolescent idiopathic scoliosis with certain risk factors. CT, although not routinely employed in the initial evaluation of scoliosis, may have a select role in characterizing the bone anomalies of congenital scoliosis and in perioperative planning. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
Journal of the American College of Radiology
Choosing the appropriate imaging in children with accidental traumatic spine injuries can be chal... more Choosing the appropriate imaging in children with accidental traumatic spine injuries can be challenging because the recommendations based on scientific evidence at this time differ from those applied in adults. This differentiation is due in part to differences in anatomy and physiology of the developing spine. This publication uses scientific evidence and a panel of pediatric experts to summarize best current imaging practices for children with accidental spine trauma.
Pediatric Radiology
The original version on this paper contained an error. The COI statement is incorrectly presented... more The original version on this paper contained an error. The COI statement is incorrectly presented. The correct statement is presented below: Conflicts of interest Drs. Narang, Palusci and Hedlund have been paid as expert consultants in cases of suspected abusive head trauma. Drs. Choudhary, Christian, Servaes, Nelson, Palasis, Rossi and Offiah provide medical-legal expert work in child abuse cases. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Journal of the American College of Radiology
Sinusitis is common in children that usually resolves spontaneously. Imaging is not part of the s... more Sinusitis is common in children that usually resolves spontaneously. Imaging is not part of the standard of care for initial diagnosis, however may be necessary in cases with persistent or chronic sinusitis to guide surgical intervention, or to rule out intracranial and vascular complications of sinusitis. Computed tomography (CT) and magnetic resonance imaging (MRI) are the leading imaging modalities. In this article, appropriateness in use of imaging modalities are discussed under common/clinically relevant scenarios. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
Pediatric radiology, Aug 23, 2018
Abusive head trauma (AHT) is the leading cause of fatal head injuries in children younger than 2 ... more Abusive head trauma (AHT) is the leading cause of fatal head injuries in children younger than 2 years. A multidisciplinary team bases this diagnosis on history, physical examination, imaging and laboratory findings. Because the etiology of the injury is multifactorial (shaking, shaking and impact, impact, etc.) the current best and inclusive term is AHT. There is no controversy concerning the medical validity of the existence of AHT, with multiple components including subdural hematoma, intracranial and spinal changes, complex retinal hemorrhages, and rib and other fractures that are inconsistent with the provided mechanism of trauma. The workup must exclude medical diseases that can mimic AHT. However, the courtroom has become a forum for speculative theories that cannot be reconciled with generally accepted medical literature. There is no reliable medical evidence that the following processes are causative in the constellation of injuries of AHT: cerebral sinovenous thrombosis, h...
Journal of the American College of Radiology : JACR, 2018
Headaches in children are not uncommon and have various causes. Proper neuroimaging of these chil... more Headaches in children are not uncommon and have various causes. Proper neuroimaging of these children is very specific to the headache type. Care must be taken to choose and perform the most appropriate initial imaging examination in order to maximize the ability to properly determine the cause with minimum risk to the child. This evidence-based report discusses the different headache types in children and provides appropriate guidelines for imaging these children. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and tr...
Journal of the American College of Radiology : JACR, 2017
It is now generally accepted that nontraumatic back pain in the pediatric population is common. T... more It is now generally accepted that nontraumatic back pain in the pediatric population is common. The presence of isolated back pain in a child has previously been an indication for imaging; however, recently a more conservative approach has been suggested using clinical criteria. The presence of constant pain, night pain, and radicular pain, alone or in combination, lasting for 4 weeks or more, constitute clinical red flags that should prompt further imaging. Without these clinical red flags, imaging is likely not indicated. Exceptions include an abnormal neurologic examination or clinical and laboratory findings suggesting an infectious or neoplastic etiology, and when present should prompt immediate imaging. Initial imaging should consist of spine radiographs limited to area of interest, with spine MRI without contrast to evaluate further if needed. CT of the spine, limited to area of interest, and Tc-99m bone scan whole body with single-photon emission computed tomography may be u...
Journal of magnetic resonance imaging : JMRI, Mar 1, 2017
To examine the effects of repetition time (TR) on metabolite concentration measurements in the hu... more To examine the effects of repetition time (TR) on metabolite concentration measurements in the human brain in (1) H magnetic resonance spectroscopy at 3 Tesla (T). Spectra were acquired from the posterior cingulate of five healthy adults at repetition times of 1.5 s, 3.0 s, 4.0 s, 6.0 s, and 8.0 s on a 3T MRI system. Relaxation data were also acquired for the water signal in the voxel of interest to separate tissue water and cerebrospinal fluid signal contributions. All data were quantified relative to total creatine and relative to the tissue water signal. On average, the variance for absolute metabolite concentrations was smaller than that of ratio concentrations (P = 0.003). Metabolite ratio concentrations calculated from a short TR of 1.5 s significantly differed (P < 0.05) from their "true" ratios, i.e., ratios corrected for T1 -weighting. In comparison, absolute metabolite concentrations exhibited significant differences (P < 0.05) up to a 4-s TR. To minimize p...
Neurosurgery, Mar 1, 2017
Journal of pediatric hematology/oncology, Oct 26, 2016
Identifying neuroblastoma (NBL) metastases is crucial to treatment and prognosis. Metaiodobenzylg... more Identifying neuroblastoma (NBL) metastases is crucial to treatment and prognosis. Metaiodobenzylguanidine and Tc99M bone scans are standard for identifying bony metastases but can underestimate disease. Diffusion-weighted imaging (DWI) of the spine has shown promise in evaluating bony metastases but has been limited by artifacts. Readout-segmented echo planar imaging is a technique for DWI that minimizes artifacts allowing for improved identification of spinal disease. This report illustrates the utility of DWI of the spine using readout-segmented echo planar imaging in the detection of bony NBL metastases in a child, lending support that DWI should be included in magnetic resonance imaging scans for NBL.
Journal of Pediatric Neuroradiology, 2016
Diffusion-weighted imaging (DWI) is one of the most powerful imaging tools available to radiologi... more Diffusion-weighted imaging (DWI) is one of the most powerful imaging tools available to radiologists today. DWI of the brain revolutionized neuroimaging when it was introduced in the mid-1990s. Until recently, clinically useful DWI of the spine has not been possible using standard single shot EPI techniques due to susceptibility artifacts and the need for higher spatial resolution. The novel 2D-navigator-corrected readout-segmented EPI sequence known as RESOLVE (REadout Segmentation Of Long Variable Echo trains) can obtain images with higher spatial resolution and reduced distortion of the spine RESOLVE: A Powerful Tool for Imaging the Pediatric Spine
Journal of Pediatric Neuroradiology, 2015
White matter (WM) injury is increasingly recognized as central to the impact on the quality of li... more White matter (WM) injury is increasingly recognized as central to the impact on the quality of life of patients with all severity levels of traumatic brain injury. It can be the determinant of death or persistent disability. This article reviews the characteristics of the developing brain in relation to trauma, the primary and secondary phases of WM injury, and advanced magnetic resonance techniques in the evaluation of brain trauma. Special emphasis is placed on non-accidental trauma and sports-related WM injury, respectively.
Pediatric Radiology, 2010
The Lancet Child & Adolescent Health
Journal of the American College of Radiology
Journal of Child Neurology
Purpose: Tuberous sclerosis complex is a multisystem genetic disorder characterized by multiorgan... more Purpose: Tuberous sclerosis complex is a multisystem genetic disorder characterized by multiorgan hamartomas, seizures, and developmental delay. Current consensus recommendations for tuberous sclerosis complex include brain magnetic resonance imaging (MRI) without and with contrast every 1 to 3 years until age 25 years for subependymal giant cell astrocytoma screening, and more often in patients with known subependymal giant cell astrocytoma. Recent reports in the literature regarding gadolinium deposition have prompted us to investigate the added value of intravenous contrast in this setting. Materials and Methods: Thirty-nine MRI examinations from 12 tuberous sclerosis complex patients with known subependymal giant cell astrocytoma were retrospectively reviewed for all caudothalamic groove lesions larger than 1 cm. Lesions were measured in 2 planes on both noncontrast and contrast-enhanced axial 3-dimensional (3D) T1-weighted imaging in a randomized fashion by 2 attending pediatri...
Journal of the American College of Radiology
Scoliosis is frequently encountered in childhood, with prevalence of 2%. The majority is idiopath... more Scoliosis is frequently encountered in childhood, with prevalence of 2%. The majority is idiopathic, without vertebral segmentation anomaly, dysraphism, neuromuscular abnormality, skeletal dysplasia, tumor, or infection. As a complement to clinical assessment, radiography is the primary imaging modality used to classify scoliosis and subsequently monitor its progression and response to treatment. MRI is utilized selectively to assess for neural axis abnormalities in those at higher risk, including those with congenital scoliosis, early onset idiopathic scoliosis, and adolescent idiopathic scoliosis with certain risk factors. CT, although not routinely employed in the initial evaluation of scoliosis, may have a select role in characterizing the bone anomalies of congenital scoliosis and in perioperative planning. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
Journal of the American College of Radiology
Choosing the appropriate imaging in children with accidental traumatic spine injuries can be chal... more Choosing the appropriate imaging in children with accidental traumatic spine injuries can be challenging because the recommendations based on scientific evidence at this time differ from those applied in adults. This differentiation is due in part to differences in anatomy and physiology of the developing spine. This publication uses scientific evidence and a panel of pediatric experts to summarize best current imaging practices for children with accidental spine trauma.
Pediatric Radiology
The original version on this paper contained an error. The COI statement is incorrectly presented... more The original version on this paper contained an error. The COI statement is incorrectly presented. The correct statement is presented below: Conflicts of interest Drs. Narang, Palusci and Hedlund have been paid as expert consultants in cases of suspected abusive head trauma. Drs. Choudhary, Christian, Servaes, Nelson, Palasis, Rossi and Offiah provide medical-legal expert work in child abuse cases. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Journal of the American College of Radiology
Sinusitis is common in children that usually resolves spontaneously. Imaging is not part of the s... more Sinusitis is common in children that usually resolves spontaneously. Imaging is not part of the standard of care for initial diagnosis, however may be necessary in cases with persistent or chronic sinusitis to guide surgical intervention, or to rule out intracranial and vascular complications of sinusitis. Computed tomography (CT) and magnetic resonance imaging (MRI) are the leading imaging modalities. In this article, appropriateness in use of imaging modalities are discussed under common/clinically relevant scenarios. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
Pediatric radiology, Aug 23, 2018
Abusive head trauma (AHT) is the leading cause of fatal head injuries in children younger than 2 ... more Abusive head trauma (AHT) is the leading cause of fatal head injuries in children younger than 2 years. A multidisciplinary team bases this diagnosis on history, physical examination, imaging and laboratory findings. Because the etiology of the injury is multifactorial (shaking, shaking and impact, impact, etc.) the current best and inclusive term is AHT. There is no controversy concerning the medical validity of the existence of AHT, with multiple components including subdural hematoma, intracranial and spinal changes, complex retinal hemorrhages, and rib and other fractures that are inconsistent with the provided mechanism of trauma. The workup must exclude medical diseases that can mimic AHT. However, the courtroom has become a forum for speculative theories that cannot be reconciled with generally accepted medical literature. There is no reliable medical evidence that the following processes are causative in the constellation of injuries of AHT: cerebral sinovenous thrombosis, h...
Journal of the American College of Radiology : JACR, 2018
Headaches in children are not uncommon and have various causes. Proper neuroimaging of these chil... more Headaches in children are not uncommon and have various causes. Proper neuroimaging of these children is very specific to the headache type. Care must be taken to choose and perform the most appropriate initial imaging examination in order to maximize the ability to properly determine the cause with minimum risk to the child. This evidence-based report discusses the different headache types in children and provides appropriate guidelines for imaging these children. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and tr...
Journal of the American College of Radiology : JACR, 2017
It is now generally accepted that nontraumatic back pain in the pediatric population is common. T... more It is now generally accepted that nontraumatic back pain in the pediatric population is common. The presence of isolated back pain in a child has previously been an indication for imaging; however, recently a more conservative approach has been suggested using clinical criteria. The presence of constant pain, night pain, and radicular pain, alone or in combination, lasting for 4 weeks or more, constitute clinical red flags that should prompt further imaging. Without these clinical red flags, imaging is likely not indicated. Exceptions include an abnormal neurologic examination or clinical and laboratory findings suggesting an infectious or neoplastic etiology, and when present should prompt immediate imaging. Initial imaging should consist of spine radiographs limited to area of interest, with spine MRI without contrast to evaluate further if needed. CT of the spine, limited to area of interest, and Tc-99m bone scan whole body with single-photon emission computed tomography may be u...
Journal of magnetic resonance imaging : JMRI, Mar 1, 2017
To examine the effects of repetition time (TR) on metabolite concentration measurements in the hu... more To examine the effects of repetition time (TR) on metabolite concentration measurements in the human brain in (1) H magnetic resonance spectroscopy at 3 Tesla (T). Spectra were acquired from the posterior cingulate of five healthy adults at repetition times of 1.5 s, 3.0 s, 4.0 s, 6.0 s, and 8.0 s on a 3T MRI system. Relaxation data were also acquired for the water signal in the voxel of interest to separate tissue water and cerebrospinal fluid signal contributions. All data were quantified relative to total creatine and relative to the tissue water signal. On average, the variance for absolute metabolite concentrations was smaller than that of ratio concentrations (P = 0.003). Metabolite ratio concentrations calculated from a short TR of 1.5 s significantly differed (P < 0.05) from their "true" ratios, i.e., ratios corrected for T1 -weighting. In comparison, absolute metabolite concentrations exhibited significant differences (P < 0.05) up to a 4-s TR. To minimize p...
Neurosurgery, Mar 1, 2017
Journal of pediatric hematology/oncology, Oct 26, 2016
Identifying neuroblastoma (NBL) metastases is crucial to treatment and prognosis. Metaiodobenzylg... more Identifying neuroblastoma (NBL) metastases is crucial to treatment and prognosis. Metaiodobenzylguanidine and Tc99M bone scans are standard for identifying bony metastases but can underestimate disease. Diffusion-weighted imaging (DWI) of the spine has shown promise in evaluating bony metastases but has been limited by artifacts. Readout-segmented echo planar imaging is a technique for DWI that minimizes artifacts allowing for improved identification of spinal disease. This report illustrates the utility of DWI of the spine using readout-segmented echo planar imaging in the detection of bony NBL metastases in a child, lending support that DWI should be included in magnetic resonance imaging scans for NBL.
Journal of Pediatric Neuroradiology, 2016