In Ovo Monitoring of Smooth Muscle Fiber Development in the Chick Embryo: Diffusion Tensor Imaging with Histologic Correlation

, and to determine the correlation between histologically-derived muscle fiber fraction, day of incubation and diffusion tensor imaging fractional anisotropy values and length of tracked fibers.From a set of 82 normally developing fertile chicken eggs, 5 eggs were randomly chosen each day from incubation days 5 to 18 and cooled using a dual-cooling technique prior to and during magnetic resonance imaging at 3.0 Tesla. Smooth muscle fibers of the gizzard were tracked using region of interests placed over the gizzard. Following imaging, the egg was cracked and the embryo was fixated and sectioned, and a micrograph most closely corresponding to the acquired magnetic resonance image was made. Smooth muscle fiber fraction was determined using an automated computer algorithm. development of smooth muscle tissue

In ovo serial skeletal muscle diffusion tractography of the developing chick embryo using DTI: feasibility and correlation with histology

Abstract Background Magnetic resonance imaging is a noninvasive method of evaluating embryonic development. Diffusion tensor imaging (DTI), based on the directional diffusivity of water molecules, is an established method of evaluating tissue structure. Yet embryonic motion degrades the in vivo acquisition of long-duration DTI. We used a dual-cooling technique to avoid motion artifact and aimed to investigate whether DTI can be used to monitor chick embryonic skeletal muscle development in ovo, and to investigate the correlation between quantitative DTI parameters fractional anisotropy (FA) and fiber length and quantitative histologic parameters fiber area percentage (FiberArea%) and limb length. Results From 84 normally developing chick embryos, 5 were randomly chosen each day from incubation days 5 to 18 and scanned using 3.0 Tesla magnetic resonance imaging. A dual-cooling technique is used before and during imaging. Eggs were cracked for making histological specimen after imaging. 3 eggs were serially imaged from days 5 to 18. We show that skeletal muscle fibers can be tracked in hind limb in DTI beginning with incubation day 8. Our data shows a good positive correlation between quantitative DTI and histologic parameters (FA vs FiberArea%: r= 0.943, p\u3c0.0001; Fiber_length vs Limb_length: r=0.974, p\u3c0.0001). The result of tracked fibers in DTI during incubation corresponds to the development of chick embryonic skeletal muscle as reported in the literature. Conclusion Diffusion tensor imaging can provide a noninvasive means of evaluating skeletal muscle development in ovo

Improved Siderotic Nodule Detection in Cirrhosis with Susceptibility-Weighted Magnetic Resonance Imaging: A Prospective Study

BACKGROUND: Hepatic cirrhosis is a common pathway of progressive liver destruction from multiple causes. Iron uptake can occur within the hepatic parenchyma or within the various nodules that form in a cirrhotic liver, termed siderotic nodules. Siderotic nodule formation has been shown to correlate with inflammatory activity, and while the relationship between siderotic nodule formation and malignancy remains unclear, iron distribution within hepatic nodules has known implications for the detection of hepatocellular carcinoma. We aimed to evaluate the role of abdominal susceptibility-weighted imaging in the detection of siderotic nodules in cirrhotic patients. METHODOLOGY/PRINCIPAL FINDINGS: Forty-six (46) cirrhotic patients with at least one siderotic nodule detected on previous imaging underwent both computed tomography and magnetic resonance imaging (T1-, T2-, T2*-, and susceptibility-weighted imaging) at 3.0 Tesla. Imaging data was independently analyzed by two radiologists. Siderotic nodule count was determined for each modality and imaging sequence. For each magnetic resonance imaging technique, siderotic nodule conspicuity was assessed on a 3 point scale (1 = weak, 2 = moderate, 3 = strong). More nodules were detected by susceptibility weighted imaging (n = 2935) than any other technique, and significantly more than by T2* weighted imaging (n = 1696, p<0.0001). Lesion conspicuity was also highest with susceptibility-weighted imaging, with all nodules found to be moderate (n = 6) or strong (n = 40); a statistically significant difference (p<0.001). CONCLUSIONS: Susceptibility-weighted imaging had the greatest lesion conspicuity and detected the highest number of siderotic nodules suggesting it is the most sensitive imaging technique to detect siderotic nodules in cirrhotic patients

Sonography of placental abnormalities: a pictorial review

Often overlooked during routine ultrasound evaluation of a normal pregnancy, the placenta forms the biologic interface between the mother and fetus and is critical to fetal growth and development. Malformations in development, positioning, and vascularity can have profound implications for both maternal and fetal well-being. As such, a judicious inspection of the placenta is warranted as an integral part of every screening or emergent prenatal ultrasound. Herein, we present a pictorial review of a variety of placental pathologic conditions including abnormalities in positioning, adherence, vascularity, and hemorrhage as well as potential peri-placental masses and gestational trophoblastic disease, all of which are readily encountered in a busy emergency radiology practice

Pearls and pitfalls of early obstetric ultrasound in the acute setting

First trimester ultrasound is commonly performed to establish dates or evaluate early pregnancy complications. With improvement in ultrasound technology, visualization of fetal structures has improved. While the emergent evaluation does not typically focus on detailed fetal anatomic evaluation (since this is typically performed at 18-20 weeks), various fetal structural abnormalities can now be visualized, especially during the late first trimester and early second trimester. We present a pictorial review of potential pitfalls encountered in early obstetric ultrasound with an emphasis on fetal structural abnormalities as well as normal fetal anatomy that can be confused with developmental abnormalities

Voriconazole-induced periostitis post transplant: an illustrative review of thoracic computed tomography imaging manifestations

Voriconazole, first commercially approved in 2002 as a second-generation antifungal agent, is commonly used in the immunocompromised setting as both a therapeutic and prophylactic agent. Since 2009, scattered case reports and small case series have detailed a secondary drug-related hyperfluorosis-induced painful periostitis that can occur in the treated patient population. We present a pictorial review of the thoracic imaging manifestations utilizing 3 illustrative cases in the setting of both solid organ and bone marrow transplantation. Knowledge of the relatively characteristic radiographic appearance and distribution, when coupled with the appropriate clinical context and associated laboratory findings, is important in narrowing an otherwise relatively broad differential diagnosis

Acute presentation of lhermitte-duclos disease in adult patient in association with cowden syndrome

A 33-year-old female presented to the emergency department with the chief complaint of new onset severe headache, persisting for five days, with accompanying subjective intermittent ataxia. There was no relevant history of prior migraines or similar such sentinel events. Review of systems was noncontributory. CT imaging demonstrated a nonspecific hypodense mass centered in the superior right cerebellum with mild locoregional mass effect upon the fourth ventricle without evidence of obstructive hydrocephalus. The appearance was nonspecific and considerations included subacute infarct, infiltrating glioma or cerebellitis. Subsequently, MRI was performed, demonstrating the characteristic striated morphologic appearance of dysplastic gangliocytoma or so-called Lhermitte-Duclos disease. Given the prior relevant surgical history of thyroidectomy for goiter and subcutaneous lipoma resection, the findings were felt to be in conjunction with previously undiagnosed Cowden syndrome. The patient was discharged after symptomatic pain control and scheduled non-operative follow up with neurosurgery as an outpatient. The relationship with Cowden syndrome is both clinically relevant and pertinent as well due to the heightened predisposition in these patients for a vicissitude of both benign and malignant neoplasms involving the breast, thyroid, dermis, gastrointestinal, genitourinary and central nervous systems, with annual surveillance and screening measures being highly warranted. Lhermitte-Duclos disease, so named for French neurologists Jacques Lhermitte and P Duclos after their initial description of the entity in 1920, has undergone a spectrum of growth in pathophysiologic understanding recently and is now considered to be a dysplastic gangliocytoma of the cerebellum, a WHO grade 1 tumor.1 Growth is slow and there is no reported malignant potential with clinical presentation typically entailing signs of increased intracranial pressure, obstructive hydrocephalus, and cerebellar dysfunction.1,2 The MR imaging appearance is considered diagnostic and can obviate biopsy, consisting of a tigroid, striated appearance of the nonenhancing cerebellar mass with superficial bands of alternating T2 hyper- and isointensity to grey matter, iso- and hypointense on T1-weighted imaging, with sporadic calcification reported and minimal loco-regional mass effect.3,4 A strong association with Cowden syndrome, an autosomal dominant, multigenic group of germ line mutations, is now recognized. Due to the heightened risk for a host of potential neuroectodermal related malignancies associated with this phakomatosis, patients are advised to undergo appropriate targeted annual screening and surveillance. As such, the radiologist may play an important role in first suggesting the underlying syndrome based on initial neuroimaging findings

Cesarean section scar ectopic pregnancy: a clinical case series

Cesarean scar implantation represents a rare, though growing subset of potentially life-threatening ectopic pregnancy. Because of the global increase in cesarean sections as well as the improved diagnostic abilities of transvaginal ultrasound, incidence rates have continued to rise since the first reported case in 1978. Uterine rupture and catastrophic hemorrhage can ensue when diagnosis is delayed. Additionally, a higher rate of concurrent trophoblastic myometrial invasion may increase the incidence of retained products of conception or post procedural bleeding. Endovaginal ultrasound has a reported sensitivity of 85 % for detection. In difficult cases, magnetic resonance imaging is often useful as a problem solving exam in confirming diagnostic suspicions and guiding therapeutic decisions. We present a series of five illustrative cases illustrating the range of clinical and imaging findings

Differentiation of breast cancer from fibroadenoma with dual-echo dynamic contrast-enhanced MRI.

Dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) of the breast is a routinely used imaging method which is highly sensitive for detecting breast malignancy. Specificity, though, remains suboptimal. Dynamic susceptibility contrast magnetic resonance imaging (DSC MRI), an alternative dynamic contrast imaging technique, evaluates perfusion-related parameters unique from DCE MRI. Previous work has shown that the combination of DSC MRI with DCE MRI can improve diagnostic specificity, though an additional administration of intravenous contrast is required. Dual-echo MRI can measure both T1W DCE MRI and T2*W DSC MRI parameters with a single contrast bolus, but has not been previously implemented in breast imaging. We have developed a dual-echo gradient-echo sequence to perform such simultaneous measurements in the breast, and use it to calculate the semi-quantitative T1W and T2*W related parameters such as peak enhancement ratio, time of maximal enhancement, regional blood flow, and regional blood volume in 20 malignant lesions and 10 benign fibroadenomas in 38 patients. Imaging parameters were compared to surgical or biopsy obtained tissue samples. Receiver operating characteristic (ROC) curves and area under the ROC curves were calculated for each parameter and combination of parameters. The time of maximal enhancement derived from DCE MRI had a 90% sensitivity and 69% specificity for predicting malignancy. When combined with DSC MRI derived regional blood flow and volume parameters, sensitivity remained unchanged at 90% but specificity increased to 80%. In conclusion, we show that dual-echo MRI with a single administration of contrast agent can simultaneously measure both T1W and T2*W related perfusion and kinetic parameters in the breast and the combination of DCE MRI and DSC MRI parameters improves the diagnostic performance of breast MRI to differentiate breast cancer from benign fibroadenomas