The use of 3D printed models for the pre-operative planning of surgical correction of pediatric hip deformities: a case series and concise review of the literature.

BACKGROUND AND AIM: Three-dimensional (3D) printing is prevailing in surgical planning of complex cases. The aim of this study is to describe the use of 3D printed models during the surgical planning for the treatment of four pediatric hip deformity cases. Moreover, pediatric pelvic deformities analyzed by 3D printed models have been object of a concise review. METHODS: All treated patients were females, with an average age of 5 years old. Patients' dysplastic pelvises were 3D-printed in real scale using processed files from Computed Tomography (CT) or Magnetic Resonance Imaging (MRI). Data about 3D printing, surgery time, blood loss and fluoroscopy have been recorded. RESULTS: The Zanoli-Pemberton or Ganz-Paley osteotomies were performed on the four 3D printed models, then the real surgery was performed in the operating room. Time and costs to produce 3D printed models were respectively on average 17:26 h and 34.66 €. The surgical duration took about 87.5 min while the blood loss average was 1.9 ml/dl. Fluoroscopy time was 21 sec. MRI model resulted inaccurate and more difficult to produce. 10 papers have been selected for the concise literature review. CONCLUSIONS: 3D printed models have proved themselves useful in the reduction of surgery time, blood loss and ionizing radiation, as well as they have improved surgical outcomes. 3D printed model is a valid tool to deepen the complex anatomy and orientate surgical choices by allowing surgeons to carefully plan the surgery.

Assessing 3-D Printing in Hip Replacement Surgical Planning.

PURPOSE: To evaluate the accuracy of 3-D printed models of the femoral head based on preoperative computed tomography (CT) images. Other goals were to compare the cartilage thickness of bony specimen to the printed models and calculate the standard deviation between 3-D printed models based on CT images and laser scan models. METHODS: This retrospective study analyzed 10 patients who underwent preoperative CT imaging and hip replacement. Preoperative femoral head 3-D printed models were produced from CT images. Bony specimens were collected from surgical operations and scanned using CT and 3-D laser scanning, and cartilage thickness subsequently was measured by histological analysis. Comparisons of printed models based on CT images and printed models based on 3-D laser scanning were performed by overlapping their external surfaces using dedicated software and the standard deviation was calculated. RESULTS: The average standard deviation between the bony specimen 3-D models and preoperative 3-D printed CT femoral head models was 0.651 mm. The cartilage was approximately 1.487 mm thick. DISCUSSION: The comparison between preoperative CT image-based 3-D models and the postoperative bony specimen-based models permitted evaluation of the accuracy of preoperative CT image-based 3-D printed models. Cartilage thickness was estimated indirectly by comparing models obtained by CT and laser scanning, and it was related to the calculated standard deviation to overcome the cartilage detection limit of CT. This study shows how each step can generate accuracy errors on the final 3-D printed model. A repeatable and sustainable workflow for creating accurate and reproducible 3-D printed models could overcome this issue. Moreover, orthopedic surgeons should be aware of 3-D printed model precision in clinical practice. CONCLUSIONS: This study provides encouraging results on the accuracy of 3-D printed models for surgical planning.

Biological monitoring of exposure to low concentrations of benzene in workers at a metallurgical coke production plant: new insights into S-phenylmercapturic acid and urinary benzene.

CONTEXT: Urinary S-phenylmercapturic acid (SPMA) and benzene (U-Ben) are usually measured at the end of the work shift (ES), although their kinetic of elimination is not clearly known. OBJECTIVE: To investigate SPMA and U-Ben elimination 16 h after the ES, in 93 coke production workers exposed to low benzene concentrations. MATERIALS AND METHODS: Airborne benzene (A-Ben) was measured by passive samplings, while SPMA, U-Ben, methyl-tert-butyl ether (U-MTBE), cotinine (U-Cot) and creatinine were determined on urine samples collected at ES and before the beginning of the next work shift (next BS). RESULTS: Median A-Ben concentrations were 17.2 µg/m3 in the personal and 34.7 µg/m3 in the stationary samplings. SPMA was always detectable, whereas U-Ben was below the limit of quantification in 26.7% of the ES and 35.6% of the next BS samples, and U-MTBE in more than the 80.0% of the samples. At both the sampling times, SPMA and U-Ben showed a positive dependence on personal A-Ben, as well as on creatinine and U-Cot values. DISCUSSION AND CONCLUSION: SPMA and U-Ben at the next BS were dependent on the exposure to low benzene concentrations suffered in the previous work shift, prompting a reconsideration of the urine sampling time recommended by the American Conference Governmental Industrial Hygienists (ACGIH).

The Influence of Dietary Components on Early Signs of Atherosclerosis in Apparently Healthy Young-adult Males: An Observational Study of 615 Subjects.

BACKGROUND: The literature shows that a healthy diet, rich in fruits and vegetables, has positive effects on overall cardiovascular risk, protecting against atherosclerosis. DESIGN: A cross sectional study in a population of apparently healthy young-adult men with the aim of investigating dietary determinants of early atherosclerosis, assessed by measuring carotid intima-media thickness (cIMT) and flow-mediated dilation (FMD) of the brachial artery. METHODS: 615 males (mean age ± SD: 40.8±9.8 years) without overt atherosclerosis were evaluated. Dietary intake was quantified by the European Prospective Investigation into Cancer and Nutrition (EPIC) questionnaire. Intake of antioxidants was expressed in relation to total caloric intake. RESULTS: Neither absolute, recommended daily allowance or weight-related values of nutritional intake variables were associated with cIMT. Vitamin E to total calories intake (odds ratio, OR=0.08, 95%CI=0.03-0.89) was inversely associated with impaired FMD. Non-nutritional correlates of FMD <10% were: age (OR=1.02, 95%CI=1.0-1.05) and waist circumference (OR=1.03, 95%CI=1.0-1.06), and those of cIMT >0.8 mm were age (OR=1.10, 95%CI=1.05-1.15), pack-years (OR=1.02, 95%CI=1.0-1.04), C-reactive protein (OR=1.17, 95%CI=1.04-1.33) and total cholesterol (OR=1.01, 95%CI=1.0-1.02). CONCLUSION: Differences in the factors correlating with cIMT >0.8 mm and FMD <10% might have implications for cardiovascular risk reduction. A lower antioxidant to caloric intake ratio might be a risk factor for impaired FMD.

Long-term results of hybrid therapy in patients with atrial fibrillation who develop atrial flutter during flecainide infusion.

The flecainide infusion test has been proposed to screen candidates for hybrid pharmacological and ablation therapy. We report the long-term follow-up of 154 consecutive patients with paroxysmal or persistent atrial fibrillation (AF) who developed atrial flutter (AFL) during flecainide infusion (IC AFL), treated with inferior vena cava-tricuspid annulus isthmus catheter ablation and oral flecainide (hybrid therapy). Over a mean of 54.1 +/- 13.1 months 82 patients (53%) remained free of AF and AFL. Flecainide was discontinued because of adverse effects in 6 patients (4%). A history of persistent AF, and the documentation of >/=1 spontaneous AFL episode before the flecainide test were independent predictors of successful hybrid therapy. In patients with paroxysmal AF without documented spontaneous AFL, the long-term efficacy of hybrid therapy was 38.5% (P = 0.03). The flecainide infusion test reliably detects candidates for hybrid therapy. The efficacy of this therapy is maintained over the long-term with a high patient compliance.

[Assessment of occupational exposure to PAH in coke-oven workers of Taranto steel plant through biological monitoring]. / Valutazione dell'esposizione professionale a IPA in lavoratori della cokeria dello stabilimento siderugico di Taranto mediante monitoraggio biologico.

OBJECTIVE: This study aims at evaluating the occupational exposure to polycyclic aromatic hydrocarbons (PAH) through biological monitoring and at investigating the influence of selected genetic polymorphisms on the levels of internal dose biomarker. DESIGN: A cross-sectional study has been conducted on the basis of biological measurements in order to evaluate the levels of PAH exposure. SETTING: PAH exposure assessment has been carried out in a coke-oven of one of the largest European steel plants (ILVA, Taranto), in the context of the program of medical surveillance carried in collaboration with the ILVA Occupational Health Service. PARTICIPANTS: 355 coke-oven workers exposed to PAH were enrolled from the 3 batteries of the coke oven plant. Maintenance workers and industrial cleaners were included. MAIN OUTCOME MEASURES: The measurement of urinary levels of 1-hydroxypyrene (1-OHP) as biomarker of internal dose has been carried out, as well as the evaluation of metabolic polymorphisms of the cytochrome P450 1A1 (CYP1A1), glutathione S-transferases mu (GSTM1) and theta (GSTT1) as biomarkers of susceptibility. RESULTS: The median value of urinary 1-OHP was 1,05 microMol/Molcreat. The difference between the groups was statistically significant, with the highest value observed in the maintenance group (median 1,71, range 0,06-14,69 microMol/Molcreat). It is remarkable that 25% of the workers exceeded the proposed benchmark guideline value of2,3 microMol/Molcreat. No statistical difference was found in relation to smoking habits. Workers with GSTT1 null genotype had higher 1-OHP levels than those with wild type (p = 0,06). CONCLUSIONS: The levels of biomarker of internal dose reflect a critical exposure to PAH in the coke-oven plant. Further observations are needed to better investigate the role of GSTT1 on the 1-OHP levels.