Purpose: Advances in medicine and multidisciplinary care have resulted in increased life expectan... more Purpose: Advances in medicine and multidisciplinary care have resulted in increased life expectancy and improved quality of life for patients with chronic congenital urological conditions (CUC). Current survival into adulthood approaches 80%. These patients are often followed with multiple serial radiographic studies to monitor their health and improve clinical outcomes. We created an inter-disciplinary improvement program to optimize the utilization of diagnostic imaging (DI) for patients with CUC, i.e. patients with Spina Bifida (SB) and Posterior Urethral Valves (PUV). In this study we present the baseline data on cost and dosimetry associated with DI in this patient population during their care in a Pediatric Hospital. Methods: A collaborative study was undertaken to review DI practices to determine utilization of DI resources, patient dosimetry, and cost to the healthcare system. IRB approval was obtained. A cohort of patients with CUC treated from birth to age 21 years was ide...
LEARNING OBJECTIVES 1) Identify basic skills, techniques, and pitfalls of freehand invasive sonog... more LEARNING OBJECTIVES 1) Identify basic skills, techniques, and pitfalls of freehand invasive sonography, with specific focus on small part applications. 2) Define and discuss technical aspects, rationale, and pitfalls involved in musculoskeletal, breast, head and neck, and pediatric interventional sonographic care procedures. 3) Successfully perform basic portions of hands-on US-guided procedures in a tissue simulation learning model, to include core biopsy, small abscess coaxial catheter drainage, cyst and ganglion aspiration, lymphatic malformation macrocyst access, soft tissue foreign body removal, and intraarticular steroid injection. 4) Incorporate these component skill sets into further life-long learning for expansion of competency and preparation for more advanced interventional sonographic learning opportunities. ABSTRACT
Iodinated and gadolinium contrast agents pose some risk for certain pediatric patients, including... more Iodinated and gadolinium contrast agents pose some risk for certain pediatric patients, including allergic-like reactions, contrast-induced nephropathy (CIN) and nephrogenic systemic fibrosis (NSF). Digital flat-panel detectors enhance image quality during angiography and might allow use of more dilute contrast material to decrease risk of complications that might be dose-dependent, such as CIN and NSF. To assess the maximum dilution factors for iodine- and gadolinium-based contrast agents suitable for vascular imaging with fluoroscopy and digital subtraction angiography (DSA) on digital flat-panel detectors in an animal model. We performed selective catheterization of the abdominal aorta, renal artery and common carotid artery on a rabbit. In each vessel we performed fluoroscopy and DSA during contrast material injection using iodinated and gadolinium contrast material at 100%, 80%, 50%, 33% and 20% dilutions. An image quality score (0 to 3) was assigned by each of eight evaluators. Intracorrelation coefficient, paired t-test, one-way repeated analysis of variance, Spearman correlation and receiver operating characteristic curve analysis were applied to the data. Overall the image quality scores correlated linearly with dilution levels. For iodinated contrast material, the optimum cut-off level for DSA when a score of at least 2 is acceptable is above 33%; it is above 50% when a score of 3 is necessary. For gadolinium contrast material, the optimum cut-off for DSA images is above 50% when a score of at least 2 is acceptable and above 80% when a score of 3 is necessary. Knowledge of the relationship between image quality and contrast material dilution might allow a decrease in overall contrast load while maintaining appropriate image quality when using digital flat-panel detectors.
As interventional procedures have become pro-gressively more sophisticated and lengthy, the poten... more As interventional procedures have become pro-gressively more sophisticated and lengthy, the potential for high patient radiation dose has increased. Staff exposure arises from patient scatter, so steps to minimize patient dose will in turn reduce operator and staff dose. The practice of ALARA in an interventional radiology (IR) suite, there-fore, requires careful attention to technical detail in order to reduce patient dose. The choice of imaging modality should minimize radiation when and where possible. In this paper practical steps are outlined to reduce patient dose. Further details are included that specifically reduce oper-ator exposure. Challenges unique to pediatric intervention are reviewed. Reference is made to experience from modern pediatric interventional suites. Given the potential for high exposures, the practice of ALARA is a team responsibility. Various measures are outlined for considera-tion when implementing a quality assurance (QA) program for an IR service.
Pulmonary nodules in pediatric oncology patients can present a diagnostic and treatment dilemma. ... more Pulmonary nodules in pediatric oncology patients can present a diagnostic and treatment dilemma. Imaging findings are often nonspecific and tissue diagnosis may be required for appropriate treatment. The smaller subpleural nodules may not be visualized and cannot be palpated during video-assisted thoracoscopic surgical (VATS) resection. Preoperative localization has been beneficial in obtaining an adequate pathological specimen. This study presents experience in a large pediatric hospital using CT-guided preoperative localization of pulmonary nodules combining two previously utilized techniques, hook wire and methylene blue blood patch localization. A search of the electronic medical record utilizing a medical record search application was performed to identify all patients who underwent preoperative lung nodule localization during a 12.5-year period (July 1999 through January 2012). A retrospective chart review of these patients was then performed. Pre- and postoperative imaging, i...
Clinical cancer research : an official journal of the American Association for Cancer Research, Jan 15, 2017
Purpose: HSV1716 is an oncolytic herpes simplex virus-1 (HSV-1) studied in adults via injection i... more Purpose: HSV1716 is an oncolytic herpes simplex virus-1 (HSV-1) studied in adults via injection into the brain and superficial tumors. To determine the safety of administering HSV1716 to pediatric patients with cancer, we conducted a phase I trial of image-guided injection in young patients with relapsed or refractory extracranial cancers.Experimental Design: We delivered a single dose of 10(5) to 10(7) infectious units of HSV1716 via computed tomography-guided intratumoral injection and measured tumor responses by imaging. Patients were eligible for up to three more doses if they achieved stable disease. We monitored HSV-1 serum titers and shedding by PCR and culture.Results: We administered a single dose of HSV1716 to eight patients and two doses to one patient. We did not observe any dose-limiting toxicities. Adverse events attributed to virus included low-grade fever, chills, and mild cytopenias. Six of eight HSV-1 seronegative patients at baseline showed seroconversion on day 2...
JPEN. Journal of parenteral and enteral nutrition, Jan 8, 2016
Establishing postnatal nutrition delivery is challenging in neonates with immature sucking and sw... more Establishing postnatal nutrition delivery is challenging in neonates with immature sucking and swallowing ability. Enteral feeding is the gold standard for such patients, but their small size and fragility present challenges in nasogastric (NG) feeding tube placement. Feeding tubes are typically placed with x-ray guidance, which provides minimal soft tissue contrast and exposes the baby to ionizing radiation. This research investigates magnetic resonance (MR) guidance of NG feeding tube placement in neonates to provide improved soft tissue visualization without ionizing radiation. A novel feeding tube incorporating 3 solenoid coils for real-time tracking and guidance in the MR environment was developed. The feeding tube was placed 5 times in a rabbit with conventional x-ray guidance to assess mechanical stability and function. After x-ray procedures, the rabbit was transferred to a neonatal MR system, and the tube was placed 5 more times. In procedures guided by x-ray and MR, the fe...
ABSTRACT A cloacal malformation is a congenital malformation in which the urinary tract, gynecolo... more ABSTRACT A cloacal malformation is a congenital malformation in which the urinary tract, gynecological system and distal rectum fail to separate and form a common channel with a single perineal opening. Precise anatomical information is required to plan surgery and predict prognosis for children with this abnormality. Conventional fluoroscopic studies provide limited information, primarily due to the overlap of structures and inability to make accurate measurements. Rotational fluoroscopy and 3-D reconstruction help clarify overlapping structures and allow for precise measurement of the common channel, thereby helping to predict the complexity of the surgical case as well as the long-term prognosis regarding bowel, bladder and sexual function.
ABSTRACT PURPOSE Because of the high morbidity of thromboembolic disease and the difficultly of a... more ABSTRACT PURPOSE Because of the high morbidity of thromboembolic disease and the difficultly of anticoagulation in some patients, inferior vena cava (IVC) filters are used as an alternative prophylactic measure for prevention of pulmonary embolism (PE). Concern about the long term morbidity of permanent filters has increased interest in retrievable filters, but experience with their use in children has been limited. We review our experience with IVC filters in pediatric population. METHOD AND MATERIALS Retrospective review of all children who underwent placement and/or retrieval of IVC filters over a 10 year period at our pediatric institution was performed. RESULTS Patient population included 11 females and 7 males from 11 to 18 years of age (mean 15 years). Indications for filter placement included deep venous thrombosis (DVT) and PE, contraindications for anticoagulation and failed anticoagulation. 17 filters were successfully inserted at our institution. One child had the filter (Gunther tulip) inserted at an outside institution which was retrieved at our institute. Before 2003, 6 filters were placed, all were permanent (2 Greenfield and 4 trapease). Since the availability of retrievable filters at our institute (2003), 9 of 11 filters placed were retrievable. The 9 retrievable included 8 Gunther tulip (G-T) and 1 recovery; the 2 permanent were 1 trapease and 1 venatech. 4 G-T and 1 recovery filter were successfully retrieved. No immediate complications occurred during placement or retrieval. The mean interval time between placement and retrieval was 74 days. Filter retrieval was not attempt in 4 children: 2 due to recurrent thrombotic disease, 1 lost to follow-up and 1 is being followed for DVT. 1 G-T filter could not be retrieved due to long indwell time (356 days). CONCLUSION Placement and retrieval of IVC filters can be safely and successfully performed in children. We noted an increase in the use of IVC filters in children at our institution since the availability of retrievable filters at our institute. Our experience with retrievable IVC filters has been encouraging, allowing us to offer a safe, effective temporary prophylatic measure for children at high risk of PE or with contraindications to anticoagulation. CLINICAL RELEVANCE/APPLICATION 1. Management of pulmonary embolism in children.
ABSTRACT PURPOSE Typical indices of Skin Entrance Dose and Dose Area Product in interventional ra... more ABSTRACT PURPOSE Typical indices of Skin Entrance Dose and Dose Area Product in interventional radiology (IR) provide no information about effective dose (ED) or individual organ dose. We evaluated ED and organ dose of digital pulsed angiography and fluoroscopy dose in a modern pediatric IR suite. METHOD AND MATERIALS All studies were performed on a Philips Integris bi-plane angio/interventional system. Using MOSFET dosimetry in a 5 y.o. phantom typical single plane DSA abdominal aortography protocols were performed using 9" and 12" image intensifiers (II) in AP, lateral, and oblique orientations. Cerebral angiography was evaluated with a 9" II in AP bi-plane and lateral and oblique single plane projections. AP and lateral abdominal and cerebral fluoroscopy was performed at the 3 commercially available settings (Low, Normal, High). RESULTS ED in mSv: Abd aortography 12"/9" II (AP=0.48/0.60, Lat=2.13/2.38, Obl=0.89/1.14). Cerebral 9" II (AP Bi-plane=0.11, Lat=0.009, Obl=0.12). Fluoroscopy Dose (mSv/min): Low/Normal/High: Abd(AP=0.77/1.13/2.00, Lat=2.13/2.82/5.19), Cerebral(AP=0.1/0.14/0.23, Lat=0.04/0.06/0.1). Selected organ doses will be presented. CONCLUSION Fluoroscopy dose, effective dose, and specific organ dosimetry can be estimated for angiography in a modern pediatric IR suite. Similar dosimetry studies should be performed for CTA and conventional fluoroscopy so relative dose comparisons can be made. CLINICAL RELEVANCE/APPLICATION Fluoroscopy dose, Effective Dose and specific organ dose can be estimated for angiography in a modern pediatric interventional radiology suite.
Purpose: Advances in medicine and multidisciplinary care have resulted in increased life expectan... more Purpose: Advances in medicine and multidisciplinary care have resulted in increased life expectancy and improved quality of life for patients with chronic congenital urological conditions (CUC). Current survival into adulthood approaches 80%. These patients are often followed with multiple serial radiographic studies to monitor their health and improve clinical outcomes. We created an inter-disciplinary improvement program to optimize the utilization of diagnostic imaging (DI) for patients with CUC, i.e. patients with Spina Bifida (SB) and Posterior Urethral Valves (PUV). In this study we present the baseline data on cost and dosimetry associated with DI in this patient population during their care in a Pediatric Hospital. Methods: A collaborative study was undertaken to review DI practices to determine utilization of DI resources, patient dosimetry, and cost to the healthcare system. IRB approval was obtained. A cohort of patients with CUC treated from birth to age 21 years was ide...
LEARNING OBJECTIVES 1) Identify basic skills, techniques, and pitfalls of freehand invasive sonog... more LEARNING OBJECTIVES 1) Identify basic skills, techniques, and pitfalls of freehand invasive sonography, with specific focus on small part applications. 2) Define and discuss technical aspects, rationale, and pitfalls involved in musculoskeletal, breast, head and neck, and pediatric interventional sonographic care procedures. 3) Successfully perform basic portions of hands-on US-guided procedures in a tissue simulation learning model, to include core biopsy, small abscess coaxial catheter drainage, cyst and ganglion aspiration, lymphatic malformation macrocyst access, soft tissue foreign body removal, and intraarticular steroid injection. 4) Incorporate these component skill sets into further life-long learning for expansion of competency and preparation for more advanced interventional sonographic learning opportunities. ABSTRACT
Iodinated and gadolinium contrast agents pose some risk for certain pediatric patients, including... more Iodinated and gadolinium contrast agents pose some risk for certain pediatric patients, including allergic-like reactions, contrast-induced nephropathy (CIN) and nephrogenic systemic fibrosis (NSF). Digital flat-panel detectors enhance image quality during angiography and might allow use of more dilute contrast material to decrease risk of complications that might be dose-dependent, such as CIN and NSF. To assess the maximum dilution factors for iodine- and gadolinium-based contrast agents suitable for vascular imaging with fluoroscopy and digital subtraction angiography (DSA) on digital flat-panel detectors in an animal model. We performed selective catheterization of the abdominal aorta, renal artery and common carotid artery on a rabbit. In each vessel we performed fluoroscopy and DSA during contrast material injection using iodinated and gadolinium contrast material at 100%, 80%, 50%, 33% and 20% dilutions. An image quality score (0 to 3) was assigned by each of eight evaluators. Intracorrelation coefficient, paired t-test, one-way repeated analysis of variance, Spearman correlation and receiver operating characteristic curve analysis were applied to the data. Overall the image quality scores correlated linearly with dilution levels. For iodinated contrast material, the optimum cut-off level for DSA when a score of at least 2 is acceptable is above 33%; it is above 50% when a score of 3 is necessary. For gadolinium contrast material, the optimum cut-off for DSA images is above 50% when a score of at least 2 is acceptable and above 80% when a score of 3 is necessary. Knowledge of the relationship between image quality and contrast material dilution might allow a decrease in overall contrast load while maintaining appropriate image quality when using digital flat-panel detectors.
As interventional procedures have become pro-gressively more sophisticated and lengthy, the poten... more As interventional procedures have become pro-gressively more sophisticated and lengthy, the potential for high patient radiation dose has increased. Staff exposure arises from patient scatter, so steps to minimize patient dose will in turn reduce operator and staff dose. The practice of ALARA in an interventional radiology (IR) suite, there-fore, requires careful attention to technical detail in order to reduce patient dose. The choice of imaging modality should minimize radiation when and where possible. In this paper practical steps are outlined to reduce patient dose. Further details are included that specifically reduce oper-ator exposure. Challenges unique to pediatric intervention are reviewed. Reference is made to experience from modern pediatric interventional suites. Given the potential for high exposures, the practice of ALARA is a team responsibility. Various measures are outlined for considera-tion when implementing a quality assurance (QA) program for an IR service.
Pulmonary nodules in pediatric oncology patients can present a diagnostic and treatment dilemma. ... more Pulmonary nodules in pediatric oncology patients can present a diagnostic and treatment dilemma. Imaging findings are often nonspecific and tissue diagnosis may be required for appropriate treatment. The smaller subpleural nodules may not be visualized and cannot be palpated during video-assisted thoracoscopic surgical (VATS) resection. Preoperative localization has been beneficial in obtaining an adequate pathological specimen. This study presents experience in a large pediatric hospital using CT-guided preoperative localization of pulmonary nodules combining two previously utilized techniques, hook wire and methylene blue blood patch localization. A search of the electronic medical record utilizing a medical record search application was performed to identify all patients who underwent preoperative lung nodule localization during a 12.5-year period (July 1999 through January 2012). A retrospective chart review of these patients was then performed. Pre- and postoperative imaging, i...
Clinical cancer research : an official journal of the American Association for Cancer Research, Jan 15, 2017
Purpose: HSV1716 is an oncolytic herpes simplex virus-1 (HSV-1) studied in adults via injection i... more Purpose: HSV1716 is an oncolytic herpes simplex virus-1 (HSV-1) studied in adults via injection into the brain and superficial tumors. To determine the safety of administering HSV1716 to pediatric patients with cancer, we conducted a phase I trial of image-guided injection in young patients with relapsed or refractory extracranial cancers.Experimental Design: We delivered a single dose of 10(5) to 10(7) infectious units of HSV1716 via computed tomography-guided intratumoral injection and measured tumor responses by imaging. Patients were eligible for up to three more doses if they achieved stable disease. We monitored HSV-1 serum titers and shedding by PCR and culture.Results: We administered a single dose of HSV1716 to eight patients and two doses to one patient. We did not observe any dose-limiting toxicities. Adverse events attributed to virus included low-grade fever, chills, and mild cytopenias. Six of eight HSV-1 seronegative patients at baseline showed seroconversion on day 2...
JPEN. Journal of parenteral and enteral nutrition, Jan 8, 2016
Establishing postnatal nutrition delivery is challenging in neonates with immature sucking and sw... more Establishing postnatal nutrition delivery is challenging in neonates with immature sucking and swallowing ability. Enteral feeding is the gold standard for such patients, but their small size and fragility present challenges in nasogastric (NG) feeding tube placement. Feeding tubes are typically placed with x-ray guidance, which provides minimal soft tissue contrast and exposes the baby to ionizing radiation. This research investigates magnetic resonance (MR) guidance of NG feeding tube placement in neonates to provide improved soft tissue visualization without ionizing radiation. A novel feeding tube incorporating 3 solenoid coils for real-time tracking and guidance in the MR environment was developed. The feeding tube was placed 5 times in a rabbit with conventional x-ray guidance to assess mechanical stability and function. After x-ray procedures, the rabbit was transferred to a neonatal MR system, and the tube was placed 5 more times. In procedures guided by x-ray and MR, the fe...
ABSTRACT A cloacal malformation is a congenital malformation in which the urinary tract, gynecolo... more ABSTRACT A cloacal malformation is a congenital malformation in which the urinary tract, gynecological system and distal rectum fail to separate and form a common channel with a single perineal opening. Precise anatomical information is required to plan surgery and predict prognosis for children with this abnormality. Conventional fluoroscopic studies provide limited information, primarily due to the overlap of structures and inability to make accurate measurements. Rotational fluoroscopy and 3-D reconstruction help clarify overlapping structures and allow for precise measurement of the common channel, thereby helping to predict the complexity of the surgical case as well as the long-term prognosis regarding bowel, bladder and sexual function.
ABSTRACT PURPOSE Because of the high morbidity of thromboembolic disease and the difficultly of a... more ABSTRACT PURPOSE Because of the high morbidity of thromboembolic disease and the difficultly of anticoagulation in some patients, inferior vena cava (IVC) filters are used as an alternative prophylactic measure for prevention of pulmonary embolism (PE). Concern about the long term morbidity of permanent filters has increased interest in retrievable filters, but experience with their use in children has been limited. We review our experience with IVC filters in pediatric population. METHOD AND MATERIALS Retrospective review of all children who underwent placement and/or retrieval of IVC filters over a 10 year period at our pediatric institution was performed. RESULTS Patient population included 11 females and 7 males from 11 to 18 years of age (mean 15 years). Indications for filter placement included deep venous thrombosis (DVT) and PE, contraindications for anticoagulation and failed anticoagulation. 17 filters were successfully inserted at our institution. One child had the filter (Gunther tulip) inserted at an outside institution which was retrieved at our institute. Before 2003, 6 filters were placed, all were permanent (2 Greenfield and 4 trapease). Since the availability of retrievable filters at our institute (2003), 9 of 11 filters placed were retrievable. The 9 retrievable included 8 Gunther tulip (G-T) and 1 recovery; the 2 permanent were 1 trapease and 1 venatech. 4 G-T and 1 recovery filter were successfully retrieved. No immediate complications occurred during placement or retrieval. The mean interval time between placement and retrieval was 74 days. Filter retrieval was not attempt in 4 children: 2 due to recurrent thrombotic disease, 1 lost to follow-up and 1 is being followed for DVT. 1 G-T filter could not be retrieved due to long indwell time (356 days). CONCLUSION Placement and retrieval of IVC filters can be safely and successfully performed in children. We noted an increase in the use of IVC filters in children at our institution since the availability of retrievable filters at our institute. Our experience with retrievable IVC filters has been encouraging, allowing us to offer a safe, effective temporary prophylatic measure for children at high risk of PE or with contraindications to anticoagulation. CLINICAL RELEVANCE/APPLICATION 1. Management of pulmonary embolism in children.
ABSTRACT PURPOSE Typical indices of Skin Entrance Dose and Dose Area Product in interventional ra... more ABSTRACT PURPOSE Typical indices of Skin Entrance Dose and Dose Area Product in interventional radiology (IR) provide no information about effective dose (ED) or individual organ dose. We evaluated ED and organ dose of digital pulsed angiography and fluoroscopy dose in a modern pediatric IR suite. METHOD AND MATERIALS All studies were performed on a Philips Integris bi-plane angio/interventional system. Using MOSFET dosimetry in a 5 y.o. phantom typical single plane DSA abdominal aortography protocols were performed using 9" and 12" image intensifiers (II) in AP, lateral, and oblique orientations. Cerebral angiography was evaluated with a 9" II in AP bi-plane and lateral and oblique single plane projections. AP and lateral abdominal and cerebral fluoroscopy was performed at the 3 commercially available settings (Low, Normal, High). RESULTS ED in mSv: Abd aortography 12"/9" II (AP=0.48/0.60, Lat=2.13/2.38, Obl=0.89/1.14). Cerebral 9" II (AP Bi-plane=0.11, Lat=0.009, Obl=0.12). Fluoroscopy Dose (mSv/min): Low/Normal/High: Abd(AP=0.77/1.13/2.00, Lat=2.13/2.82/5.19), Cerebral(AP=0.1/0.14/0.23, Lat=0.04/0.06/0.1). Selected organ doses will be presented. CONCLUSION Fluoroscopy dose, effective dose, and specific organ dosimetry can be estimated for angiography in a modern pediatric IR suite. Similar dosimetry studies should be performed for CTA and conventional fluoroscopy so relative dose comparisons can be made. CLINICAL RELEVANCE/APPLICATION Fluoroscopy dose, Effective Dose and specific organ dose can be estimated for angiography in a modern pediatric interventional radiology suite.
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