Biomedical subjects
Publications and source records attributed to F A Hoffer.
We present a unique case of Budd-Chiari syndrome caused by Gaucher's disease. The diagnosis was based on Doppler sonography, magnetic resonance imaging, contrast-enhanced three-dimensional magnetic resonance angiography, standard venography, and venous pressure measurements and was confirmed histologically.
PURPOSE: In a preclinical model of neuroblastoma, administration of irinotecan daily 5 days per week for 2 consecutive weeks ([qd x 5] x 2) resulted in greater antitumor activity than did a single 5-day course with the same total dose. We evaluated this protracted schedule in children. PATIENTS AND METHODS: Twenty-three children with refractory solid tumors were enrolled onto a phase I study. Cohorts received irinotecan by 1-hour intravenous infusion at 20, 24, or 29 mg/m(2) (qd x 5) x 2 every 21 days. RESULTS: The 23 children (median age, 14.1 years; median prior regimens, two) received 84 courses. Predominant diagnoses were neuroblastoma (n = 5), osteosarcoma (n = 5), and rhabdomyosarcoma (n = 4). The dose-limiting toxicity was grade 3/4 diarrhea and/or abdominal cramps in six of 12 patients treated at 24 mg/m(2), despite aggressive use of loperamide. The maximum-tolerated dose (MTD) on this schedule was 20 mg/m(2)/d. Five patients had partial responses and 16 had disease stabilization. On day 1, the median systemic exposure to SN-38 (the active metabolite of irinotecan) at the MTD was 106 ng-h/mL (range, 41 to 421 ng-h/mL). CONCLUSION: This protracted schedule is well tolerated in children. The absence of significant myelosuppression and encouraging clinical responses suggest compellingly that irinotecan be further evaluated in children using the (qd x 5) x 2 schedule, beginning at a dose of 20 mg/m(2). These results imply that data obtained from xenograft models can be effectively integrated into the design of clinical trials.
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PURPOSE: We report the treatment of 10 children for progressive desmoid tumor not amenable to standard surgical or radiation therapy with the use of vinblastine (VBL) and methotrexate (MTX). PATIENTS AND METHODS: Ten patients aged 6.4 to 18 years with primary (two patients) or recurrent (eight patients) desmoid tumor were treated with VBL and MTX for 2 to 35 months. Patients with recurrent tumors had been previously treated with surgical resection with (two patients) or without (five patients) radiation therapy or with radiation therapy alone (one patient). No patient had previously received cytotoxic chemotherapy. The tumor response was assessed at routine intervals by physical examination and magnetic resonance imaging (MRI). RESULTS: Five patients had clinical evidence of response to therapy with complete resolution (three patients) or partial resolution (two patients) of physical examination and radiographic abnormalities. Three patients had stable disease during 10 to 35 months of treatment. Two of these patients had progressive disease 9 and 37 months after treatment stopped; one patient had no progression 16 months after therapy. Two additional patients with stable disease had chemotherapy discontinued after 2 and 3 months. Common side effects included mild alopecia and myelosuppression and moderate nausea and vomiting. In patients with responding tumors, MRI showed decreased tumor size and, in two patients, changes consistent with fibrosis and decreased cellularity of the tumor. CONCLUSION: Combination chemotherapy with VBL and MTX appears to control desmoid tumor without significant acute or long-term morbidity in most children. This may allow for further growth and development in these patients, which may decrease the morbidity of subsequent definitive therapy.
OBJECTIVE: The purpose of this study is to report our technique for MR cholangiography in children and to describe the postoperative imaging findings in children who have undergone liver transplantation from living related donors. CONCLUSION: MR cholangiography can be used to delineate anatomy and morphology of the bile ducts of the left lateral segment graft in children who have undergone liver transplantation from living related donors. This information can guide treatment of postoperative biliary complications with interventional radiology or surgery.
OBJECTIVE: Our objective was to offer a preliminary description of MR lymphangiography; its uses and limitations; and its findings in infants, children, and young adults. SUBJECTS AND METHODS: Twenty-nine patients underwent 32 MR lymphangiographic examinations for evaluation of vascular malformations, other masses, soft-tissue swelling, gigantism, fluid accumulation, or pain. MR lymphangiography was based on a heavily T2-weighted fast spin-echo sequence and a maximum-intensity-projection algorithm. We assessed the axial and off-axial lymphatic channels in conjunction with MR venography to help differentiate veins from lymphatics. Correlation was made with published lymphangiograms and anatomic diagrams to assist interpretation and (when available) with histologic specimens (n = 11) for validation. RESULTS: Presumed lymphatic channels were seen universally, although 14 examinations showed incomplete venous signal suppression. Lymphatic channels appeared normal in eight children and in 20 of the 21 asymptomatic contralateral limbs. Ten patients had an increased number and size of off-axial channels, including seven children with large, diffuse low-flow vascular malformations. Enlarged axial and off-axial channels were seen in five patients, four of whom had Klippel-Trénaunay syndrome. Six patients, each with an extensive hemangioendothelioma, Klippel-Trénaunay syndrome, Gorham syndrome, or unilateral body edema, showed absence or interruption of axial channels. CONCLUSION: MR lymphangiography appears to be a useful noninvasive technique to study superficial and deep lymphatic channels in children with local or diffuse vascular lesions or swelling of extremities. Its limitations notwithstanding, the technique may offer further insight into the nature of vascular anomalies, may direct therapy, and may predict prognosis.
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This article addresses the most common types of interventional procedures performed in the pediatric abdomen. Nonvascular interventions are stressed because they are more common than vascular interventions.
The diagnostic, developmental, and surgical aspects of left pulmonary artery sling associated with right lung agenesis in 3 patients are described. Cardiac catheterization may be avoided by the combined use of echocardiography and magnetic resonance imaging and/or computed tomography.
This paper reviews the techniques that we employ to perform musculoskeletal magnetic resonance imaging in the pediatric patient. We examine the procedures for preparation and screening of the patient and the protocols for sedation. The selection of imaging coils and sequences for the evaluation of the pediatric musculoskeletal system is also addressed, followed by a summary of scanning protocols.
Contrast angiography can demonstrate the vascular components of a vascular malformation, but can be technically challenging in small patients with complex venous anomalies. We reviewed the role of magnetic resonance venography (MRV) in the evaluation of children with predominantly low-flow, vascular malformations of the extremities. MRV (2D time-of-flight technique) and magnetic resonance (MR) imaging examinations were performed in ten young patients with congenital predominantly low-flow vascular malformations of the extremities. MR imaging was used to characterize and determine the extent of the malformations, and MRV to evaluate the deep and superficial venous channels. In all patients, MRV studies were reviewed in conjunction with contrast angiograms, considered the gold standard, to confirm the findings. All significant channel anomalies seen with contrast angiography were identified with MRV. In addition, MRV demonstrated some veins that were not intentionally opacified during contrast studies. MRV demonstrates both the superficial and deep conducting veins, whereas contrast angiography is a more directed study, evaluating only those channels intentionally opacified. Together, MR imaging and MRV data can non-invasively form the basis for determining the prognosis and choosing the individual treatment of congenital vascular malformations of the extremities.
Treatment for children with congenital deformities of the lower extremities may vary, depending on the state of the unossified skeletal structures and surrounding soft tissues. The purpose of our study was to demonstrate the spectrum of the osteochondral and extrasosseous abnormalities as depicted with MR imaging. We retrospectively reviewed MR examinations of 13 limbs of ten children (aged 1 month-9 years, mean 2.1 years) with longitudinal and transverse deformities of the lower extremities. The lesions imaged were fibular hemimelia (n = 5), tibial hemimelia (n = 5), and congenital constriction bands (n = 3). Each examination was assessed for abnormalities in the osteocartilaginous and extraosseous (articular or periarticular components such as ligaments, tendons, and menisci; the muscles and the arteries) structures. Abnormalities were seen in all patients. Osteocartilaginous abnormalities in the patients with longitudinal deformities included abnormal distal femoral epiphyses, abnormal proximal tibial physes, hypertrophied and dislocated proximal fibular epiphyses, unsuspected fibular and tibial remnants, and absence or coalition of the tarsal bones. No osteocartilaginous abnormalities were seen in the patients with congenital constriction bands. Articular abnormalities about the knee in patients with either form of hemimelia included absent cruciate ligaments and menisci, dislocated or absent cartilaginous patellae, absent patellar tendons, and abnormal collateral ligaments. All but one limb imaged had absent or attenuated muscle groups. Of the nine MR arteriograms performed at the level of the knee, eight were abnormal. The normal popliteal trifurcation was absent or in an abnormal location. We conclude that MR imaging of children with congenital lower extremity deformities shows many osteochondral and extraosseous abnormalities that are not depicted by conventional radiography. This information can help to plan early surgical intervention and prosthetic rehabilitation.
The purpose of this study was to describe the appearance on magnetic resonance (MR) imaging of hepatic hemangioma, and how the appearance changes in infants who have received interferon alpha-2a (IFN) treatment. We retrospectively studied 16 MR examinations in seven infants (mean age 3.2 months; range 5 days to 13 months) who were symptomatic with hepatic hemangiomas. Five of these seven patients had MR examinations both before and after treatment with IFN. In six of the seven patients, the hepatic hemangiomas were multicentric; they were usually discrete, well-defined nodules, best seen on T2-weighted images as high intensity lesions. One patient had a large solitary heterogeneous lesion. They all exhibited fast flow (seen as flow voids on spin-echo images and high signal intensity structures on gradient-recalled echo images) and enlarged hepatic arteries and veins. There was enlargement of the proximal abdominal aorta with distal tapering. Treatment was followed by accelerated regression of the hemangiomas in size and number and variable shrinkage of the enlarged vessels. As the tumor nodules regressed, they were replaced by normal-appearing hepatic parenchyma; neither fat nor fibrosis was detected by MR imaging.
The authors review their experience with transrectal drainage of pelvic abscesses in seven children and adolescents (6-16 years old). Initial access was guided by transrectal ultrasound with an endovaginal transducer followed by fluoroscopy for placement of self-retaining catheters (8.5-10 F) using the Seldinger technique. All abscesses were successfully drained without complications. A transrectal catheter was well tolerated by most patients without spontaneous dislodgment. Catheters were removed after an average of 4 days (range 3-7 days). Transrectal drainage of pelvic abscess with transrectal sonographic and fluoroscopic guidance seems to be a safe and effective procedure in children.
OBJECTIVE: Intravenous antibiotics and surgical drainage are the accepted methods of treating osteomyelitis complicated by abscess formation. The objective of this study was to determine whether percutaneous drainage of subperiosteal abscess is a potential treatment for osteomyelitis. MATERIALS AND METHODS: Three pediatric patients with subperiosteal abscesses from acute osteomyelitis had percutaneous drainage with sonographic and fluoroscopic guidance using a Seldinger technique and an 8-F catheter. RESULTS: Two patients required no further intervention and had the drainage catheter removed after 72 h. After completing a course of antibiotics they healed completely. One patient, after a week of purulent drainage, required open drainage including a bone debridement of an area of septic necrosis. CONCLUSION: Percutaneous drainage of subperiosteal abscess may be an alternative to surgical drainage when medical therapy alone is inadequate. Development of intraosseous abscess, necrosis or persistent drainage suggests further intervention may be necessary.
Localization of skeletal tracer in a neuroblastoma primary is common but localization in extraskeletal metastatic sites has not received recognition. Tc-99m MDP concentration in hepatic or pulmonary metastases was noted in three of ten patients with such metastases. Lesion size appears to be important for demonstrating these metastases with Tc-99m MDP. This was particularly true for hepatic metastases, which were identified only when they were 5 cm or greater in diameter.
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Radiographic evaluation of central venous catheters (CVCs) with contrast material is a commonly performed procedure in pediatric radiology, but the criteria for interpreting the results of such studies are not well described in the literature. Careful evaluation of the images from a contrast material-enhanced CVC study frequently demonstrates a cause of CVC malfunction. In a series of 166 contrast-enhanced CVC studies performed in children, 112 studies (67%) demonstrated abnormal results. The most common abnormalities were mural thrombus, catheter tip thrombus, catheter tip against the vessel wall, and sleeve thrombus. Other causes of catheter malfunction include reservoir thrombus, catheter break, and catheter malposition. When catheter malfunction is due to catheter thrombus formation, the patient is usually treated with urokinase (bolus injection or infusion). Short catheters that ended in the innominate or subclavian vein had a much higher frequency of abnormalities than longer catheters that ended in the superior vena cava or right atrium.