Benchmarking Various Radiomic Toolkit Features While Applying the Image Biomarker Standardization Initiative toward Clinical Translation of Radiomic Analysis

Journal of Digital Imaging - The image biomarkers standardization initiative (IBSI) was formed to address the standardization of extraction of quantifiable imaging metrics. Despite its effort,...     

Accuracy of conventional digital palpation and ultrasound of the cricothyroid membrane in obese women in labour

Success of cricothyroidotomy depends on accurate identification of anatomical neck landmarks. Anaesthetists palpated the cricothyroid membrane of 28 obese and 28 non‐obese women in labour (cut‐off BMI 30 kg.m^?2) and marked the entry point for device insertion with an ultraviolet invisible pen. Ultrasonography was used to mark the midpoint of the cricothyroid membrane and the distance between the two marks was measured. The median (IQR [range]) distance between the two marks was significantly greater in the obese than the non‐obese patients (5 (2–9.5 [0–34]) mm vs 1.8 (0.1–6 [0–15]) mm, respectively; p = 0.02). The cricothyroid membrane was accurately identified with digital palpation in only 39% (11/28) of obese compared with 71% (20/28) of non‐obese patients (p = 0.03). Increased neck circumference in obese patients was significantly associated with inaccuracy in locating the cricothyroid membrane. Percutaneous identification of the cricothyroid membrane in obese women in labour was poor. Pre‐procedural ultrasound may help improved the identification of neck landmarks for cricothyroidotomy.     

“Ride-on” technique and other simple and logical solutions to counter most common complications of silicone implants in augmentation rhinoplasty

Augmentation rhinoplasty can be carried out using a wide range of materials including autologous bone and/or cartilage as well as alloplasts. Use of biologic bone and cartilage grafts results in lower infection rates, but they are associated with long-term resorption and donor-site morbidity. Alloplastic materials, in particular silicone, have been associated in literature with extrusion, necrosis of the tip, mobility and deviation or displacement of the implant, immobile nasal tip and infection. However, they have the advantages of being readily available and easy to reshape with no requirement for harvesting autografts.

Aim:

To overcome these problems associated with silicone implants for which the authors have devised a novel technique, the “rideon technique”.

Materials and Methods:

The present study was carried out on 11 patients over a period of 4 years. The authors have devised a simple technique to fix the silicone implant and retain it in place. Restricting the implant to only dorsum avoided common complications related to the silicone implant.

Results:

The authors have used this technique in 11 patients with encouraging results. Follow-up ranged from 12 months to 36 months during which patients were assessed for implant mobility, implant extrusion and tip necrosis. There was no incidence of above mentioned complications in these patients.

Conclusion:

The “rideon technique” provides excellent stability to silicone implants and restricting the implant only to dorsum not only eliminates chances of tip necrosis and thus implant extrusion but also maintains natural shape, feel and mobility of the tip.KEY WORDS: Alloplasts, autografts, rhinoplasty, silicone implants     

Contrast‐Enhanced Sonography for Monitoring Neoadjuvant Chemotherapy in Soft Tissue Sarcomas

Neoadjuvant chemotherapy is a mainstay in treating soft tissue sarcomas. Soft tissue sarcomas can show an increase in size and central necrosis, with a decrease in the viable tumor, as an initial response to neoadjuvant chemotherapy. Thus, the maximum tumor diameter may not reliably assess the response to this therapy. Contrast‐enhanced sonography may address this limitation. We evaluated 4 patients with soft tissue sarcomas by contrast‐enhanced sonography, performed concomitantly with conventional imaging (computed tomography, magnetic resonance imaging, or positron emission tomography). Quantitative analysis was also performed on 1 sarcoma. A viable, enhancing tumor versus tumor necrosis was nearly identical on contrast‐enhanced sonography and conventional imaging. Preliminary results demonstrate potential for contrast‐enhanced sonographic monitoring of soft tissue sarcomas during neoadjuvant chemotherapy.     

Renal Mechanisms of Association between Fibroblast Growth Factor 1 and Blood Pressure

The fibroblast growth factor 1 (FGF1) gene is expressed primarily in the kidney and may contribute to hypertension. However, the biologic mechanisms underlying the association between FGF1 and BP regulation remain unknown. We report that the major allele of FGF1 single nucleotide polymorphism rs152524 was associated in a dose-dependent manner with systolic BP (P=9.65×10⁻⁵) and diastolic BP (P=7.61×10⁻³) in a meta-analysis of 14,364 individuals and with renal expression of FGF1 mRNA in 126 human kidneys (P=9.0×10⁻³). Next-generation RNA sequencing revealed that upregulated renal expression of FGF1 or of each of the three FGF1 mRNA isoforms individually was associated with higher BP. FGF1-stratified coexpression analysis in two separate collections of human kidneys identified 126 FGF1 partner mRNAs, of which 71 and 63 showed at least nominal association with systolic and diastolic BP, respectively. Of those mRNAs, seven mRNAs in five genes (MME, PTPRO, REN, SLC12A3, and WNK1) had strong prior annotation to BP or hypertension. MME, which encodes an enzyme that degrades circulating natriuretic peptides, showed the strongest differential coexpression with FGF1 between hypertensive and normotensive kidneys. Furthermore, higher level of renal FGF1 expression was associated with lower circulating levels of atrial and brain natriuretic peptides. These findings indicate that FGF1 expression in the kidney is at least under partial genetic control and that renal expression of several FGF1 partner genes involved in the natriuretic peptide catabolism pathway, renin-angiotensin cascade, and sodium handling network may explain the association between FGF1 and BP.     

An Anatomic Study on Whether the Patella is Centered in an Ideal Anteroposterior Radiograph of the Knee

BackgroundCurrently, an anteroposterior radiograph of the knee is judged based on a centered position of the patella between the femoral condyles. We are not aware of any anatomic literature supporting this recommendation.Questions/PurposesOrthogonal images are required for accurate assessment of knee deformity. Although an image with the patella centered at the distal femur is generally accepted as a true anteroposterior (AP) radiograph of the knee, there is minimal anatomic data to support that this view is orthogonal to a true lateral view of the knee where the condyles are overlapped. We designed an anatomical study to test the relationship between these two radiographic views.MethodsWe studied 428 well-preserved cadaveric skeletons ranging from 40 to 79 years of age at death. Centering of the patella was calculated based on distal femoral and patellar widths. Multiple regression analysis was then performed to determine the relationship between patellar centering and age, gender, ethnicity, mechanical lateral distal femoral angle (mLDFA), medial proximal tibial angle (MPTA), femoral anteversion, and contralateral centering.ResultsAverage patellar centering was 0.13 ± 0.04, indicating that the average patella was laterally positioned in the distal femur. Only mLDFA and contralateral centering showed statistically significant independent correlations with patellar centering with modest standardized beta coefficients of 0.10 and 0.23, respectively.ConclusionsIn the average specimen, the patella is laterally deviated by 13% of the condylar width. Clinicians should be aware that a lateral view with the femoral condyles overlapped is not always orthogonal to a patella-centered AP view when planning and implementing deformity correction.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-014-9419-3) contains supplementary material, which is available to authorized users.     

Pyrazinamidase activity of Mycobacterium tuberculosis--a test of sensitivity to pyrazinamide

Pyrazinamidase activity has been found to correlate with pyrazinamide sensitivity in strains of Mycobacterium tuberculosis. In vitro sensitivity to pyrazinamide in acidified L?wenstein-Jensen medium, and pyrazinamidase activity by the Wayne method, were determined in 378 clinical isolates of M. tuberculosis. A close correlation was observed between the results of both tests. This method of detecting pyrazinamidase activity was found to be a rapid, simple and reliable substitute for pyrazinamide sensitivity testing, and it overcomes the difficulty of growing M. tuberculosis at pH 5.5, as required in the standard method.