Person:

Grant, Frederick

Summary: Lymphedema is the progressive enlargement of tissue due to inadequate lymphatic function. Obesity-induced lymphedema of the lower extremities can occur once a patient’s body mass index (BMI) exceeds 50. We report our first patient with obesity-induced lower extremity lymphedema who was followed prospectively before and after weight loss. A 46-year-old woman with a BMI of 80 presented to our Lymphedema Program complaining of bilateral lower extremity swelling. Lymphoscintigraphy showed impaired lymphatic drainage of both lower extremities consistent with lymphedema. She was referred to a bariatric surgical weight-loss center and underwent a sleeve gastrectomy. After reaching her new steady-state BMI of 36 eighteen months following her procedure, lymphoscintigraphy showed no improvement in lower extremity lymphatic function. Patients at risk for obesity-induced lymphedema should be counseled that they should seek weight-loss interventions before their BMI reaches 50, a threshold at which point lower extremity lymphedema may occur. Unlike other comorbidities that reverse following massive weight loss, obesity-induced lymphedema may not resolve.

The medical cost associated with back pain in the United States is considerable and growing. Although the differential diagnosis of back pain is broad, epidemiological studies suggest a correlation between adult and adolescent complaints. Injury of the pars interarticularis is one of the most common identifiable causes of ongoing low back pain in adolescent athletes. It constitutes a spectrum of disease ranging from bone stress to spondylolysis and spondylolisthesis. Bone stress may be the earliest sign of disease. Repetitive bone stress causes bone remodeling and may result in spondylolysis, a non-displaced fracture of the pars interarticularis. A fracture of the pars interarticularis may ultimately become unstable leading to spondylolisthesis. Results in the literature support the use of bone scintigraphy to diagnose bone stress in patients with suspected spondylolysis. Single photon emission computed tomography (SPECT) provides more contrast than planar bone scintigraphy, increases the sensitivity and improves anatomic localization of skeletal lesions without exposing the patient to additional radiation. It also provides an opportunity for better correlation with other imaging modalities, when necessary. As such, the addition of SPECT to standard planar bone scintigraphy can result in a more accurate diagnosis and a better chance for efficient patient care. It is our expectation that by improving our ability to correctly diagnose bone stress in patients with suspected injury of the posterior elements, the long-term cost of managing this condition will be lowered.

The year, 2016, marked the 75th anniversary of Dr. Saul Hertz first using radioiodine to treat a patient with thyroid disease. In November of 1936, a luncheon was held of the faculty of Harvard Medical School where Karl Compton, PhD, president of the Massachusetts Institute of Technology was invited to give a presentation entitled “What Physics Can Do for Biology and Medicine.” Saul Hertz who attended the luncheon spontaneously asked the very pertinent question that perhaps changed the course of treatment of thyroid disease, “Could iodine be made radioactive artificially?” We review the events leading up to the asking of this question, the preclinical investigations by Dr. Hertz and his colleague Arthur Roberts prior to the treatment of the first patient and what occurred in the years following this landmark event. This commentary seeks to set the record straight to the sequence of events leading to the first radioiodine therapy, so that those involved can be recognized with due credit.

PET/CT plays an important role in the diagnosis, staging and management of many pediatric malignancies. The techniques for performing PET/CT examinations in children have evolved, with increasing attention focused on reducing patient exposure to ionizing radiation dose whenever possible and minimizing scan duration and sedation times, with a goal toward optimizing the overall patient experience. This review outlines our approach to performing PET/CT, including a discussion of the indications for a PET/CT exam, approaches for optimizing the exam protocol, and a review of different approaches for acquiring the CT portion of the PET/CT exam. Strategies for PACS integration, image display, interpretation and reporting are also provided. Most practices will develop a strategy for performing PET/CT that best meets their respective needs. The purpose of this article is to provide a comprehensive overview for radiologists who are new to pediatric PET/CT, and also to provide experienced PET/CT practitioners with an update on state-of-the art CT techniques that we have incorporated into our protocols and that have enabled us to make considerable improvements to our PET/CT practice.

Background: Lymphedema is the chronic enlargement of tissue due to inadequate lymphatic function. Diagnosis is made by history and physical examination and confirmed with lymphoscintigraphy. The purpose of this study was to assess the accuracy of lymphoscintigraphy for the diagnosis of lymphedema and to determine characteristics of patients with false-negative tests. Methods: Individuals referred to our lymphedema program with “lymphedema” between 2009 and 2016 were analyzed. Subjects were assessed by history, physical examination, and lymphoscintigraphy. Patient age at presentation, duration of lymphedema, location of disease, gender, previous infections, and lymphedema type were analyzed. Results: The study included 227 patients (454 limbs); lymphedema was diagnosed clinically in 169 subjects and confirmed by lymphoscintigraphy in 162 (117 primary, 45 secondary; 96% sensitivity). Fifty-eight patients were thought to have a condition other than lymphedema, and all had negative lymphoscintigrams (100% specificity). A subgroup analysis of the 7 individuals with lymphedema clinically, but normal lymphoscintigrams, showed that all had primary lymphedema; duration of disease and infection history were not different between true-positive and false-negative lymphoscintigram results (P = 0.5). Two patients with a false-negative test underwent repeat lymphoscintigraphy, which then showed lymphatic dysfunction consistent with lymphedema. Conclusion: Lymphoscintigraphy is very sensitive and specific for lymphedema. All patients with false-negative studies had primary lymphedema. A patient with a high clinical suspicion of lymphedema and a normal lymphoscintigram should be treated conservatively for the disease and undergo repeat lymphoscintigraphy.