Uterine leiomyomata (fibroids) are the leading cause of hysterectomy in the United States. Black women have a greater fibroid burden than whites, yet no study has systematically evaluated the growth of fibroids in blacks and whites. We prospectively tracked growth for 262 fibroids (size range: 1–13 cm in diameter) from 72 premenopausal participants (38 blacks and 34 whites). Fibroid volume was measured by computerized analysis of up to four MRI scans over 12 months. We used mixed effects models to identify factors that are associated with growth, and results were converted to percent change per 6 months for clinical relevance. The median growth rate was 9% (range: −89% to +138%). Seven percent of fibroids regressed (>20% shrinkage). Tumors from the same woman grew at different rates (within-woman component of variation was twice the component among women; both were significant, P < 0.001). Black and white women less than 35 years of age had similar fibroid growth rates. However, growth rates declined with age for whites but not for blacks ( P = 0.05). The odds of a tumor growing more than 20% in 6 months also decreased with age for whites but not for blacks ( P < 0.01). Growth rates were not influenced by tumor size, location, body mass index, or parity. We conclude that ( i ) spontaneous regression of fibroids occurs; ( ii ) fibroids from the same woman grow at different rates, despite a uniform hormonal milieu; ( iii ) fibroid size does not predict growth rate; and ( iv ) age-related differences in fibroid growth between blacks and whites may contribute to the higher symptom burden for black women.
24 April 2007 in Journal of Magnetic Resonance Imaging
“When one admits that nothing is certain one must, I think, also admit that some things are much more nearly certain than others.” Bertrand Russell (1872–1970) Computed tomography (CT) is one of the largest contributors to man‐made radiation doses in medical populations. CT currently accounts for over 60 million examinations in the United States, and its use continues to grow rapidly. The principal concern regarding radiation exposure is that the subject may develop malignancies. For this systematic review we searched journal publications in MEDLINE (1966–2006) using the terms “CT,” “ionizing radiation,” “cancer risks,” “MRI,” and “patient safety.” We also searched major reports issued from governmental U.S. and world health‐related agencies. Many studies have shown that organ doses associated with routine diagnostic CT scans are similar to the low‐dose range of radiation received by atomic‐bomb survivors. The FDA estimates that a CT examination with an effective dose of 10 mSv may be associated with an increased chance of developing fatal cancer for approximately one patient in 2000, whereas the BEIR VII lifetime risk model predicts that with the same low‐dose radiation, approximately one individual in 1000 will develop cancer. There are uncertainties in the current radiation risk estimates, especially at the lower dose levels encountered in CT. To address what should be done to ensure patient safety, in this review we discuss the “as low as reasonably achievable” (ALARA) principle, and the use of MRI as an alternative to CT. J. Magn. Reson. Imaging 2007;25:900–909.
An NIH-sponsored phase I clinical trial is underway to test a potential treatment for giant axonal neuropathy (GAN) using viral-mediated GAN gene replacement (https://clinicaltrials.gov/ct2/show/NCT02362438). This trial marks the first instance of intrathecal (IT) adeno-associated viral (AAV) gene transfer in humans. GAN is a rare pediatric neurodegenerative disorder caused by autosomal recessive loss-of-function mutations in the GAN gene, which encodes the gigaxonin protein. Gigaxonin is involved in the regulation, turnover, and degradation of intermediate filaments (IFs). The pathologic signature of GAN is giant axonal swellings filled with disorganized accumulations of IFs. Herein, we describe the development and characterization of the AAV vector carrying a normal copy of the human GAN transgene (AAV9/JeT-GAN) currently employed in the clinical trial. Treatment with AAV/JeT-GAN restored the normal configuration of IFs in patient fibroblasts within days in cell culture and by 4 weeks in GAN KO mice. IT delivery of AAV9/JeT-GAN in aged GAN KO mice preserved sciatic nerve ultrastructure, reduced neuronal IF accumulations and attenuated rotarod dysfunction. This strategy conferred sustained wild-type gigaxonin expression across the PNS and CNS for at least 1 year in mice. These results support the clinical evaluation of AAV9/JeT-GAN for potential therapeutic outcomes and treatment for GAN patients.
23 August 2001 in Journal of Magnetic Resonance Imaging
The purpose of this study was to evaluate the spectrum of appearances of gastrointestinal carcinoid tumors at magnetic resonance imaging (MRI) and to elucidate patterns of appearances of carcinoid liver metastases on precontrast and postgadolinium images. The MR examinations of 29 patients (11 men, 18 women; age range, 33–87 years) with histologically confirmed gastrointestinal carcinoid tumors, representing our complete 9.5 years of experience with this entity, were retrospectively reviewed. Twelve patients had MR examinations prior to resection or biopsy of the primary tumor (preoperative group); 17 patients were imaged postsurgically (postoperative group). All MR studies were performed at 1.5 T and comprised T1‐weighted spoiled gradient echo (SGE), T2‐weighted fat‐suppressed turbo spin echo, HASTE, and serial postgadolinium T1‐weighted SGE sequences without and with fat suppression. Morphology, signal intensity, and contrast enhancement of primary tumors and of metastases to the mesentery, peritoneum, and liver were evaluated. Primary tumors were visualized in 8 of 12 patients and best demonstrated on postgadolinium T1‐weighted fat‐suppressed images. The appearance of primary tumors was a nodular mass originating from the bowel wall (4 of 12 patients) or regional uniform bowel wall thickening (4 of 12 patients) with moderate intense enhancement on postgadolinium images. In 4 of 12 patients the primary tumor was prospectively not seen. Mesenteric metastases, seen in eight patients, presented as nodular masses and were associated with mesenteric stranding in seven patients. A total of 156 liver metastases were evaluated in 16 patients. On precontrast T1‐ and T2‐weighted images, 117 metastases (75%) were hypointense and hyperintense, respectively. A total of 146 metastases (94%) were hypervascular, showing moderate intense enhancement during the hepatic arterial phase, and 9 metastases (6%) were hypovascular. Twenty‐three metastases (15%) were visible only on immediate postgadolinium images. MRI is able to demonstrate findings in carcinoid tumors, including the primary tumor, mesenteric metastases, and liver metastases. Liver metastases are commonly hypervascular and may be demonstrable only on immediate postgadolinium images. J. Magn. Reson. Imaging 2001;14:261–269.