An ultrasonography-based approach for tissue modelling to inform photo-therapy treatment strategies.

Currently, diagnostic medicine uses a multitude of tools ranging from ionising radiation to histology analysis. With advances in piezoelectric crystal technology, high-frequency ultrasound imaging has developed to achieve comparatively high resolution without the drawbacks of ionising radiation. This research proposes a low-cost, non-invasive and real-time protocol for informing photo-therapy procedures using ultrasound imaging. We combine currently available ultrasound procedures with Monte Carlo methods for assessing light transport and photo-energy deposition in the tissue. The measurements from high-resolution ultrasound scans are used as input for optical simulations. Consequently, this provides a pipeline that will inform medical practitioners for better therapy strategy planning. While validating known inferences of light transport through biological tissue, our results highlight the range of information such as temporal monitoring and energy deposition at varying depths. This process also retains the flexibility of testing various wavelengths for individual-specific geometries and anatomy.

Optical investigation of three-dimensional human skin equivalents: A pilot study.

Human skin equivalents (HSEs) are three-dimensional living models of human skin that are prepared in vitro by seeding cells onto an appropriate scaffold. They recreate the structure and biological behaviour of real skin, allowing the investigation of processes such as keratinocyte differentiation and interactions between the dermal and epidermal layers. However, for wider applications, their optical and mechanical properties should also replicate those of real skin. We therefore conducted a pilot study to investigate the optical properties of HSEs. We compared Monte Carlo simulations of (a) real human skin and (b) two-layer optical models of HSEs with (c) experimental measurements of transmittance through HSE samples. The skin layers were described using a hybrid collection of optical attenuation coefficients. A linear relationship was observed between the simulations and experiments. For samples thinner than 0.5 mm, an exponential increase in detected power was observed due to fewer instances of absorption and scattering.

Assessment of active inflammation in juvenile dermatomyositis: a novel magnetic resonance imaging-based scoring system.

OBJECTIVE: To assess the reproducibility of a novel scoring system that we have developed for the objective assessment of acute inflammatory change in JDM. This system defines markers of inflammatory change in four muscle groups and the surrounding soft tissues. METHODS: Forty-eight children (33 girls) underwent retrospective assessment of their MRI studies by two musculoskeletal paediatric radiologists for the presence of disease activity. Each observer performed the readings on two separate occasions. The degree of concordance between the two observers and between the two readings was assessed using kappa analysis. The reproducibility of the total score was determined using Bland-Altman analysis. RESULTS: There was fair to moderate agreement between the two observers for all the examined disease activity markers in all muscle groups. There was good intra-observer agreement between the two readings. There was no difference according to the side evaluated. The mean total score (out of 20) for Observer 1 was 7.9 and for Observer 2 was 7.5 (mean difference -0.4, 95% limits of agreement -6.8 to 6.0), while the mean total scores for Observer 1 were 9.0 for the first reading and 7.9 for the second reading (mean difference 1.0, 95% limits of agreement -2.6 to 4.6). CONCLUSION: Markers of inflammatory change in JDM can be observed on MRI in a reliable fashion and have been used to make a reliable and objective scoring system. The accuracy of the proposed scoring system is acceptable for the single reader, although there is more variability between two different individuals.

Synchronous renal masses in patients with a nonrenal malignancy: incidence of metastasis to the kidney versus primary renal neoplasia and differentiating features on CT.

OBJECTIVE: The purpose of this study was to establish the contemporaneous frequency of metastases within the kidney as opposed to primary renal tumors in patients with an active primary nonrenal malignancy and to identify the differentiating features. MATERIALS AND METHODS: We retrospectively identified all patients with an active primary nonrenal malignancy (group 1) who had also undergone at least 2 contrast-enhanced abdominal CT examinations spaced 1 year apart. The radiologic and pathologic data of these cases were reviewed and the incidence of metastasis to the kidney versus primary renal tumors established. These data were compared with a separate group who presented with primary renal malignancy from the outset (group 2). RESULTS: In the study were 2340 patients with primary nonrenal malignancy (group 1) and 231 patients with a primary renal malignancy (group 2). For group 1, the mean age was 63 years and 51% were men; for group 2, the mean age was 59 years, and 58% were men. The differences were not statistically significant. Thirty-six patients in group 1 had a malignant renal mass; 21 were a result of kidney metastasis and the remaining 15 were a synchronous primary renal tumor (0.9% vs 0.6%). The kidney was the eighth most common site of metastatic spread. Metastases to the kidney were statistically more likely with higher tumor stage of the primary nonrenal malignancy (68% vs 46%, p = 0.0006) and in those with other sites of metastasis (p = 0.012, positive likelihood ratio [LR+] = 6.75). Compared with primary renal tumors, metastases to the kidney were more often solid (86% vs 53%, p = 0.019, LR+ = 3.7) and endophytic (76% vs 33%, p = 0.017, LR+ = 2.29). There were too few cases with calcification and bilateral tumors to reach a statistically significant conclusion. Tumor size, polar predominance, and enhancement pattern were similar in the two groups. The primary renal tumors seen in group 1 versus group 2 were similar regarding age and sex distribution, cell type, median size, and tumor stage. CONCLUSION: Metastases to the kidney are uncommon in modern radiologic practice (0.9%, 21/2340 in this study), and a renal mass seen in a patient with nonrenal malignancy is nearly as likely to be an incidental primary renal tumor. Metastasis is more likely in those with higher tumor stage or if other viscera are also affected and is usually an asymptomatic, small, endophytic, and solid mass. If a renal mass seen in a patient with primary nonrenal malignancy proves to be a synchronous primary renal tumor, its cell type and stage will be similar to sporadic primary renal tumors.

Erectile dysfunction: the role of penile Doppler ultrasound in diagnosis.

Erectile dysfunction (ED) is a common and debilitating condition with physical, psychological, and pharmacological aetiologies. The physical causes can be divided into problems with arterial inflow, structural penile abnormalities, or problems with the venous occlusion mechanism. Penile Doppler sonography is a specialized technique requiring a thorough knowledge of the topic in order to aid diagnosis and direct subsequent treatment. This technique is indicated in those patients with erectile dysfunction who do not respond to oral pharmacological agents (e.g., PDE-5 inhibitors). This pictorial essay will visit the anatomy and physiology of penile erection, the technique for performing the procedure, and review the imaging features for specific causes of ED.

An improved method of assessing esophageal emptying using the timed barium study following surgical myotomy for achalasia.

INTRODUCTION: The timed barium study (TBS) is used to assess esophageal emptying in patients with achalasia. Improvement in emptying correlates with outcome after endoscopic therapy, but the results of the TBS have been variable after myotomy. Our aim was to evaluate a new method for assessing improvement in emptying after myotomy. METHODS: A TBS was performed before and 3-6 months after myotomy in 30 patients. Emptying was assessed by measuring the percent difference in area of the barium column on films obtained 1 and 5 min after ingesting 150 ml of barium. Initial esophageal clearance was also assessed by comparing the area of the barium column on 1-min images obtained before and after therapy. Both measures were compared to clinical outcome. RESULTS: After myotomy, 21 patients (70%) had no symptoms, four (13%) had mild, and five (17%) had moderate/severe symptoms. Using the standard method, esophageal emptying before and after surgery were not significantly different (25% vs. 37%; p = 0.22) and did not correlate with clinical outcome. In contrast, initial esophageal clearance improved significantly (median 81%) and correlated with clinical outcome. CONCLUSION: Esophageal emptying measured by the standard method is not useful to assess outcome after myotomy. However, initial esophageal clearance correlates well with clinical outcome.

Extensive transperineal template biopsies of prostate: modified technique and results.

OBJECTIVES: To describe the modified technique and results of extensive transperineal template prostate biopsies in men with a high risk of prostate cancer in whom repeated transrectal biopsies are not diagnostic. METHODS: Men who had a rising prostate-specific antigen (PSA) level and had at least two sets of benign octant biopsies or two or more prior biopsies containing high-grade prostatic intraepithelial neoplasia or atypical small acinar proliferation were included. A biplanar transrectal ultrasound probe was attached to a brachytherapy stepping unit and a standard 0.5-cm brachytherapy template was positioned over the perineum. In the transverse image, the prostate was divided into right and left and anterior, middle, and posterior regions, and three to five transperineal biopsy cores were taken in each of the six regions through the template. RESULTS: Sixty men underwent extensive transperineal template biopsies. Their mean age was 64 years (SD 6.4), the median PSA level was 12.9 ng/mL (range 4.6 to 35.7), and the median prostate volume was 54 cm3 (range 34 to 199). Cancer was detected in 23 men (38%), of whom 17 (74%) had Gleason grade 6, 5 (21%) Gleason grade 7, and 1 (4%) Gleason grade 9 disease. Cancer was identified in the anterior region of the prostate alone in 12 men (60%). One man required overnight admission for hematuria and two developed urinary retention; no cases of sepsis developed. CONCLUSIONS: In men with a clinical suspicion of prostate cancer, but benign or equivocal prostate biopsies, extensive transperineal template biopsy of the prostate is a useful diagnostic tool. It allows sampling of the whole prostate in a systematic and safe fashion.