Distally based anterolateral-thigh (ALT) flap with the aid of multidetector computed tomography.

The applicability of the proximally based pedicled anterolateral thigh (ALT) flap has been well described with good results, but the use of a distally based ALT flap around the knee has not been fairly presented. The case of a male patient with a soft-tissue defect around the knee who underwent skin reconstruction based on an ipsilateral distally based ALT flap is presented. Multidetector-computed tomography (MDCT) was used to study the vessels of the lower extremity, which allowed easy interpretation as it provided anatomical images with three-dimensional anatomy reconstructions. Because of the knowledge of the anatomical connections with the lateral femoral circumflex artery (LFCA) and the superior lateral genicular artery (SLGA), the distally based ALT flap could be safely transferred. Soft-tissue reconstruction around the knee using the distally based ALT flap could also be performed safely and reliably with the aid of MDCT.

A model to evaluate bone substitutes for immediate implant placement.

A calcified alloplast was evaluated as a gap-filling material around implants placed immediately into fresh extraction sockets. Periodontal measurements and computed tomography scans were obtained to evaluate the clinical effectiveness of the alloplast when compared with demineralized freeze-dried bone. To determine whether this alloplast would be a suitable grafting material, 14 patients were selected to evaluate the extraction socket as a model for routine histologic confirmation of the efficacy and biocompatibility of bone substitutes. The results of this study showed the following: (1) human extraction sockets can be models for the study of bone/implant interaction; (2) the alloplast was well tolerated and demonstrated no inflammation through histologic evaluation of core biopsies; (3) the alloplast was a suitable material when used as a gap-filling graft in sockets around immediately placed implants; and (4) dental computed tomography scans and periodontal measurements around grafted implants 6 months after the procedure provide valuable clinical information about graft healing and osteointegration.

Radiofrequency spectral analysis of attenuated ultrasound signals in experiments with echo contrast microbubbles.

Conventional gray-scale myocardial contrast echocardiography cannot distinguish perfused but attenuated from nonperfused myocardium because both may appear similar at low image intensity. We hypothesized that with radiofrequency spectral analysis of attenuated ultrasound signals, the harmonic-to-fundamental frequency ratio of the peak power spectrum (HFR(P)) could determine the presence of contrast microbubbles. We measured frequency responses of Optison microbubbles at defined degrees of ultrasound signal attenuation with different formulations of silicone (55D, 80A, and 3M); gray-scale intensities of Optison plus water compared with degassed water were analyzed at different attenuation settings (-25, -32, and -44 dB, respectively). HFR(P) values of Optison plus water were significantly higher than reference values of degassed water at each attenuation setting (55D, -14 +/- 2 dB versus -30 +/- 2 dB, P <.001; 80A, -19 +/- 2 dB versus -30 +/- 3 dB, P <.01; 3M, -22 +/- 2 dB versus -30 +/- 3 dB, P <.05), even though conventional videodensitometric analysis could not distinguish them. HFR(P) analysis objectively detects microbubbles in clinically relevant conditions of attenuation.

Real-time strain rate echocardiographic imaging: temporal and spatial analysis of postsystolic compression in acutely ischemic myocardium.

Postsystolic compression (PSC) is a sensitive indicator of regional left ventricular ischemic diastolic dysfunction. Quantitative assessment of compression patterns by strain rate imaging could determine the presence and spatial extent of PSC for the detection and analysis of acute ischemic diastolic dysfunction. With the use of a segmental left ventricular model, we evaluated time to compression/expansion crossover (T-CEC) in standard apical views. Data at baseline and after acute left anterior descending coronary artery occlusion were collected from 18 open-chest pigs. We found significant mean prolongation of T-CEC, ranging from 43.9 +/- 48.6 ms to 110.8 +/- 73.8 ms, in all apical segments and in 2 midventricular (anterior and anteroseptal) segments. Analysis of variance demonstrated that the prolonged T-CEC is spatially consistent with perfusion defect. The temporal and spatial analysis of T-CEC with the use of strain rate imaging is a new noninvasive technique for identification and topographic quantitation of ischemic diastolic dysfunction expressed by PSC.

Regional asynchrony during acute myocardial ischemia quantified by ultrasound strain rate imaging.

OBJECTIVES: We propose a new method to easily quantify asynchronous wall motion due to postsystolic shortening (PSS). We also studied the relationship of the spatial and temporal extent of PSS to the extent of myocardium at ischemic risk after variable duration of ischemia. BACKGROUND: Postsystolic shortening is a sensitive marker of asynchrony during ischemia. Current techniques for detection of asynchrony are either subjective, or invasive and time-consuming. Strain rate imaging (SRI) can noninvasively depict PSS as prolonged compression/expansion crossover. METHODS: Nineteen open-chest pigs were scanned from apical views, before and after left anterior descending coronary artery occlusion. Strain rates were derived offline from tissue Doppler velocity cineloops. The time from electrocardiographic R-wave to the occurrence of compression/expansion crossover (TCEC) was calculated. Prolonged TCEC during ischemia was identified using a standardized analysis and both spatial (% of left ventricle) and temporal extent were quantified. The extent of myocardium at risk was measured in seven animals from dye-stained specimens. RESULTS: Prolonged TCEC was found in all ischemic segments. There was a good correlation (r = 0.91; p < 0.001) and good agreement between the spatial distributions of prolonged TCEC and myocardium at risk. The extent of myocardium at risk was better approximated by TCEC measurement (36 +/- 7% vs. 39 +/- 8%, respectively; p = NS) than by wall motion analysis (47 +/- 17%, p < 0.05). The duration of occlusion did not prolong TCEC. CONCLUSIONS: Prolonged TCEC consistently occurs in ischemic myocardium and is apparently not affected by the duration of ischemia. Standardized analysis of TCEC in SRI closely quantifies the extent of ischemic myocardium. This new method may be a useful tool in other cardiac conditions associated with regional diastolic asynchrony.

Effect of interleukin-2 and selenium on the growth of squamous cell carcinoma cells.

OBJECTIVES: The objectives of this study were to determine whether the expression of the interleukin-2 (IL-2) receptors on squamous cell carcinoma cells can be enhanced in the presence of selenium (Se) and contribute to a greater retardation of tumor growth after locoregional therapy with IL-2. STUDY DESIGN: The growth of the cells was studied after in vitro or dietary supplementation with Se in a murine model. RESULTS: Treatment of established tumors in hosts supplemented with Se with peritumoral injections of IL-2 resulted in 50% reduction of tumor size, whereas treatment of early tumors resulted in 72.4% reduction. The effect was most likely related to a combination of enhanced immune responsiveness and enhanced IL-2 receptor expression on the tumor cells. CONCLUSIONS AND SIGNIFICANCE: The data suggested that local immunotherapy with IL-2 in hosts supplemented with Se may represent an effective modality of treatment for the prevention of recurrences at the site of conventionally treated primary tumors, including tumors that do not express IL-2 receptors.

Myocardial contrast echocardiography: texture analysis for identification of nonperfused versus perfused myocardium.

This study examined texture analysis for objective identification of nonperfused myocardial segments in myocardial contrast echocardiographic (MCE) images. Short-axis MCE images from six open chest pigs after coronary artery ligation were examined. Six of 26 features (low gray level run emphasis, high gray level run emphasis, sum mean, sum variance, coefficient of variance and diagonal variance) demonstrated a significant texture value difference (P < 0.01) between the nonperfused and perfused segments with minimal statistical distribution overlap between the two groups. This study demonstrates that texture features other than mean gray level can objectively distinguish nonperfused from perfused myocardium in MCE images and may thus augment the diagnostic accuracy of current analysis techniques.

Urodynamic characterization of nonobstructive voiding dysfunction in symptomatic elderly men.

PURPOSE: The pathogenesis of lower urinary tract symptoms in men without bladder outlet obstruction has not been well characterized. Therefore, we defined the urodynamic abnormalities associated with symptomatic nonobstructive voiding dysfunction, and determined the relationship between age and type of dysfunction. MATERIALS AND METHODS: Video urodynamic studies of symptomatic men without outlet obstruction were examined. The criterion for a normal bladder outlet was a pressure gradient across the prostatic urethra of 5 cm. water or less in the absence of distal stricture. A maximum isometric contraction pressure less than 60 cm. water was regarded as impaired detrusor contractility. Detrusor instability was defined as involuntary detrusor contractions during filling or the inability to suppress a detrusor contraction after initiation of flow. Patients were categorized into 4 groups based on the urodynamic findings. RESULTS: Of 193 men (mean age 69.6+/-10.5 years) 40.9% had detrusor instability (group 1), 31.1% had impaired contractility (group 2), 10.8% had detrusor instability and impaired contractility (group 3), and 17.1% were urodynamically normal (group 4). Average patient age was significantly lower in group 4 than all other groups. Bladder capacity was lowest in group 1, and group 3 had the lowest voiding efficiency. Maximum flow rate, bladder compliance and symptom scores were not different among the 4 groups. The prevalence of detrusor instability with and without impaired contractility increased, while the proportion of patients without urodynamic abnormalities decreased with age. Bladder contractility did not correlate with age. CONCLUSIONS: The nonobstructed patient population comprises several groups that are functionally distinct while symptomatically similar. Thus, treatment of nonobstructed cases based on symptoms may lead to inappropriate pharmacological therapy and unsuccessful clinical outcomes.

Management of a patient with advanced AIDS and toxic epidermal necrolysis using human growth hormone and G-CSF.

Toxic epidermal necrolysis (TEN) is a serious drug reaction that is occurring with increased frequency among those affected with HIV and AIDS. It carries a grave prognosis for those with advanced AIDS and massive skin involvement. We report a severe case of TEN treated with wound care, intravenous nutrition, human growth hormone (hgh), and granulocyte colony-stimulating factor (G-CSF).

[Cytotoxicity of povidone-iodine on cultured mammalian cells].

Cytotoxicity of povidone-iodine on cultured mammalian cells was studied using cultured Chinese hamster lung cells (V 79 cells). Treatment of V 79 cells with povidone-iodine at 100-500 micrograms/ml for 24 to 72 hr induced a growth inhibition of the cells in a dose-dependent manner. Although minimum inhibition of survival of V 79 cells was elicited in cultures treated with povidone-iodine at 100-300 micrograms/ml for 2 to 24 hr, treatment at 500 micrograms/ml for 6 to 24 hr resulted in decrease in cell survival in a treatment time-dependent fasion. Exposure of cells to povidone-iodine at 100-500 micrograms/ml for 2 hr caused inhibition of DNA, RNA or protein synthesis of cells up to 13.9% of untreated cells. These results indicate that cytotoxicity of povidone-iodine occurs in dose- and treatment time-dependent manners and that povidone-iodine induces inhibition of DNA, RNA and protein syntheses of cells, even by the treatment which causes no reduction of cell survival.

[Cytotoxicity of dental iodine glycerin on cultured mammalian cells].

Cytotoxicity of dental iodine glycerin was studied using cultured Chinese hamster lung cells (V79 cells). Treatment with dental iodine glycerin at 0.33 - 0.1v/v% for 24 to 72 hr elicited a minor inhibition of growth of V79 cells. The cell growth, however, was remarkably inhibited when the cells were treated with dental iodine glycerin at 0.3v/v%. No inhibitory effect on survival of V79 cells was observed in cultures treated with dental iodine glycerin at 0.03 - 0.1v/v% for 2 to 24 hr. Meanwhile, treatment with dental iodine glycerin at 0.3v/v% for 2 hr or more induced 100% inhibition of cell survival. Exposure of cells to dental iodine glycerin at 0.3v.v% for 2 hr caused decrease in DNA, RNA or protein synthesis of the cells up to 54.4% of untreated cells. These results indicate that there is a big difference in cytotoxicity induced by treatment of V79 cells with dental iodine glycerin at concentrations between 0.1v/v% and 0.3v.v%, and that treatment with dental iodine glycerin induced inhibition of DNA, RNA and protein synthesis of the cells and the inhibition occurs even by the treatment which causes no reduction of cell survival.