Power modulation contrast enhanced ultrasound for postoperative perfusion monitoring following free tissue transfer in head and neck surgery

This feasibility study evaluated whether contrast enhanced ultrasound (CEU) was able to assess free flap perfusion following free tissue transfer in the head and neck region. Thirty-six patients underwent standard clinical monitoring (SCM) and CEU postoperatively. The time taken for each technique to detect flap failure was recorded. Qualitative CEU analysis by visual assessment predicted survival in 30/30 (100%) and failure in 5/6 (83%) flaps with sensitivity, specificity, positive (PPV) and negative (NPV) predictive values of 100, 86, 97 and 100%, respectively. Quantitative CEU measurement of blood volume (α) values within healthy perfused flaps was over 60 times higher than in failing flaps (8.25 ± 2.82 dB vs. 0.12 ± 0.17 dB, respectively, P < 0.0001). If a cut-off α value of <1.5 dB was used to predict future flap failure, the accuracy of the test was 100% (sensitivity, specificity, PPV, NPV). If a cut-off α value of >1.9 dB indicated flap success, the PPV and NPV are 100%. Following surgery, SCM took 76 (±15) h to detect flap failure compared with 18 (±38) h with CEU (P < 0.05). CEU is highly accurate in its ability to distinguish between perfused and failing flaps. The technique is quick (<10 min) and capable of imaging all flap types.     

Giant benign schwannoma on scalp causing 'double-head'

Abstract- Schwannomas are tumors derived from Schwann cells. They are usually small and comparatively rare on scalp. A 25-year old woman presented with huge mass on posterior side of the scalp that gave the appearance of 'double-head'. The mass was excised and reconstruction was achieved by primary closure. Histology proved to be a benign schwannoma. The patient is well at 6-months of follow up. Giant benign schwannoma on scalp is extremely rare. Clinicians that came across the giant tumors of the scalp should suspect this possibility as these tumors have favorable prognosis.     

Association of ApoE genetic variants with obstructive sleep apnea in children

BACKGROUND AND PURPOSE: Although several studies have reported an association between obstructive sleep apnea (OSA) and the chromosomal region containing the Apolipoprotein E (ApoE) gene, findings about the exact location in the ApoE gene have been inconsistent. The objective of our study was thus to determine the allele, genotype, and haplotype frequencies at several single nucleotide polymorphisms (SNPs) in the region of ApoE and test their association with OSA status in children. PATIENTS AND METHODS: Caucasian children, ranging in age from 2 to 21 years, with polysomnographic evidence of OSA (>1 obstructive apnea or obstructive hypopnea episodes per hour of sleep) were recruited in the case group. Our race- and gender-matched control group was recruited from a population-based cohort of children enrolled in the Princeton School District Study. RESULTS: Comparison of allele and genotype frequencies between cases (n=92) and controls (n=92) revealed significant differences for SNPs rs405509 and rs7412. Multivariate logistic regression analysis with age and body mass index (BMI) as covariates revealed a significant association between OSA status and SNPs rs157580, rs405509, rs769455 and rs7412. The sliding window haplotype trend regression test revealed that SNP rs405509 was included in all haplotypes that are significantly associated with OSA status. CONCLUSIONS: We conclude that polymorphisms involving more than one locus in the ApoE gene and its regulatory region are associated with OSA in children. Further studies replicating these findings in different populations are needed as are studies involving fine mapping of this region.     

Estimation of drug precipitation upon dilution of pH-controlled formulations

An equation is developed for estimating the precipitation that may occur upon diluting or injecting a (pH-)solubilized drug formulation. Since it is based on equilibrium, it is the worst case scenario for precipitation. This equation can be programmed in any commercially available spread sheet program such as Excel. According to the proposed equation, the type and the strength of the buffer species are the most significant factors that affect the pH and solubility of a drug in its microenvironment during dilution. To demonstrate the utility and robustness of the proposed equation, experimental measurements were performed using phenytoin as the model drug. The result suggests that the proposed equation can be used to indicate the possibility and the degree of precipitation that would occur upon injection. This provides a useful tool for the design of a successful pH-controlled solution formulation.     

ACR Appropriateness Criteria® Acute Onset Flank Pain-Suspicion of Stone Disease

ABSTRACT: Low dose (<3 mSv) noncontrast CT (NCCT) is the imaging study of choice for accurate evaluation of patients with acute onset of flank pain and suspicion of stone disease (sensitivity 97%, specificity 95%). NCCT can reliably characterize the location and size of an offending ureteral calculus, identify complications, and diagnose alternative etiologies of abdominal pain such as appendicitis. By comparison, the sensitivity of radiographs (59%) and ultrasound (24-57%) for the detection of renal and ureteral calculi is relatively poor. Ultrasound can accurately diagnose pelvicaliectasis and ureterectasis, but it may take several hours for these findings to develop. In the pregnant patient, however, ultrasound is a first line test as it does not expose the fetus to ionizing radiation. MR is an accurate test for the diagnosis of pelvicaliectasis and ureterectasis, but is less sensitive than CT for the diagnosis of renal and ureteral calculi. For patients with known stone disease whose stones are visible on radiographs, radiographs are a good tool for post-treatment follow-up.The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every two years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.     

Inhibition of tumorigenesis by a cytosine–DNA, methyltransferase, antisense oligodeoxynucleotide

This paper tests the hypothesis that cytosine DNA methyltransferase (DNA MeTase) is a candidate target for anticancer therapy. Several observations have suggested recently that hyperactivation of DNA MeTase plays a critical role in initiation and progression of cancer and that its up-regulation is a component of the Ras oncogenic signaling pathway. We show that a phosphorothioate-modified, antisense oligodeoxynucleotide directed against the DNA MeTase mRNA reduces the level of DNA MeTase mRNA, inhibits DNA MeTase activity, and inhibits anchorage independent growth of Y1 adrenocortical carcinoma cells ex vivo in a dose-dependent manner. Injection of DNA MeTase antisense oligodeoxynucleotides i.p. inhibits the growth of Y1 tumors in syngeneic LAF1 mice, reduces the level of DNA MeTase, and induces demethylation of the adrenocortical-specific gene C21 and its expression in tumors in vivo. These results support the hypothesis that an increase in DNA MeTase activity is critical for tumorigenesis and is reversible by pharmacological inhibition of DNA MeTase.