3D printed soft surgical planning prototype for a biliary tract rhabdomyosarcoma.

Biliary tract rhabdomyosarcoma is a soft tissue malignant musculoskeletal tumor which is located in the biliary tract. Although this tumor represents less than 1% of the total amount of childhood cancers, when localized, a >70% overall 5-year survival rate, the resection is clinically challenging and complications might exist during the biliary obstruction. Although surgery remains a mainstay, complete tumor resection is generally difficult to achieve without mutilation and severe long-term sequelae. Therefore, manufacturing multi-material 3D surgical planning prototypes of the case provides a great opportunity for surgeons to learn beforehand what they can expect. Additionally, practicing before the operation enhances the probability of success. That is why different compositions of materials have been characterized to match the mechanical properties of the liver. To do this, Dynamic Mechanical Analysis (DMA) tests and Shore hardness tests have been carried out. Amongst the material samples produced, 6%wt PVA (poly vinyl alcohol)/1%wt PHY (Phytagel)-1FT (Freeze-Thaw cycles) and 1%wt agarose appear as the best options for mimicking the liver tissue in terms of viscoelasticity. Regarding the Shore hardness, the best solution is 1%wt agarose. Additionally, a surgical planning prototype using this last material mentioned was manufactured and validated using a CT (Computed Tomography) scanner. In most of the structures the difference between the 3D model and the organ in terms of dimensions is less than 3.35 mm, which represents a low dimensional error, around 1%. On the other hand, the total manufacturing cost of the 3D physical model was €513 which is relatively low in comparison with other technologies.

Bacterial characteristics and clinical significance of ureteral double-J stents in children.

OBJECTIVE: To determine the incidence of urinary tract infection in those patients that we have used an ureteral double-J stent as internal diversion after urological procedures. MATERIAL AND METHODS: We reviewed all the medical records of patients who had a ureteral double-J stent after a urological procedure from August 2007 to May 2013. We have analyzed the following data: age, gender, type of prophylaxis, incidence of urinary tract infection (UTI), days of internal diversion with double-J stent, surgical procedure, bacterial characteristics, bacterial sensibility to antibiotics and UTI treatment. RESULTS: We have used 73 double-J stents as ureteral internal diversion in 67 patients with a mean age of 44.73±57.23. Surgical procedures were 50 laparoscopic Anderson-Hynes pyeloplasties in 49 patients, and 20 high-pressure balloon dilatation of the ureterovesical junction to treat primary obstructive megaureter in 15 patients; and 3 patients with ureterovesical obstruction after endoscopic treatment of vesicoureteral reflux. Forty three stents showed a bacterial colonization in cultures. Pseudomona aeruginosa was present in 9 (20.9%) stents. Only in 12 stents, bacterial colonization was sensible to antibiotic prophylaxis. Stent colonization was higher in boys and younger patients. Four patients had a febrile UTI. Incidence of UTI in younger patients that underwent HBPD of UVJ is higher. CONCLUSION: Bacterial colonization is frequent in double-J stents but the incidence of UTI is low. Double-J colonization is higher in younger patients. Patients that underwent HPBD have a higher risk of UTI related with ureteral double J stent.

[Anderson-Hynes pyeloplasty in children under 2 years. Is the laparoscopy the technique of choice?]. / Pieloplastia Anderson-Hynes en menores de 2 años. ¿Es la laparoscopia la técnica de elección?

OBJECTIVE: To analyze if the laparoscopic pyeloplasty is as effective as the open procedure in the ureteropelvic junction obstruction in patients under 2 years of age. PATIENTS AND METHODS: Pyeloplasties performed in children under 2 years of age between 2007 and 2010. Weight, pre and postoperative renal pelvis and calices diameter, operating time, hospital stay and complications were analyzed. RESULTS: We found no statistic differences in weight, complications, or pre and postoperative renal pelvis and calices diameter. However, we found differences in hospital stay and operating time (p<0.05). CONCLUSIONS: Laparoscopic pyeloplasty in children under 2 years of age is a good alternative technique for ureteropelvic junction obstruction, although operating time are still long.

High pressure balloon dilation of the ureterovesical junction--first line approach to treat primary obstructive megaureter?

PURPOSE: We describe the efficacy of dilation of the ureterovesical junction to treat primary obstructive megaureter. MATERIALS AND METHODS: A total of 13 patients with primary obstructive megaureter were treated from May 2008 to December 2010. Of these patients 8 were diagnosed prenatally and the others were diagnosed after a urinary tract infection. Preoperative studies included ultrasonography, voiding cystourethrography despite vesicoureteral reflux and diuretic isotopic renogram (mercaptoacetyltriglycine). With the patient under general anesthesia, high pressure balloon dilation of the ureterovesical junction was performed under direct and fluoroscopic vision until the disappearance of the narrowed ring. A Double-J(®) catheter was positioned, and 2 months later it was withdrawn and the ureterovesical junction was reviewed. A secondary treatment was performed in those in whom the ureterovesical junction was still narrow. Followup was performed with ultrasonography, cystourethrography and isotopic diuretic renography. RESULTS: A total of 18 procedures were performed in 13 patients (median age 7 months, range 4 to 24). Median diameter of the distal ureter was 14 mm (range 10 to 26), and median diameter of the renal pelvis and calyx was 27 mm (range 10 to 47) and 12 mm (range 9 to 26), respectively. Significant postoperative improvement of hydroureteronephrosis was observed in 11 of 13 patients and vesicoureteral reflux was found in 2. Only 3 patients needed ureteral reimplantation after endoscopic treatment due to hydroureteronephrosis in 2 and high grade vesicoureteral reflux in 1. CONCLUSIONS: High pressure balloon dilation of the ureterovesical junction is effective in treating primary obstructive megaureter, but long-term followup is needed.

[Laparoscopìc pyeloplasty in pediatric patients. Our initial cases and lessons learned]. / Pieloplastia laparoscópica en pacientes pediátricos. Nuestros primeros casos y lecciones aprendidas.

OBJECTIVE: To analyze the initial experience in our first patients with ureteropelvic junction obstruction (UPJO) treated by laparoscopic surgery. PATIENTS AND METHODS: All laparoscopic Anderson-Hynes pyeloplasties performed from July 2007 to April 2009 were analyzed. Before surgery, patients underwent a renal ultrasound and isotope renogram. A double J catheter was left in place and subsequently removed. Patients were followed up by ultrasound and renography. RESULTS: Fourteen patients with a median age of 8.6 years were analyzed. Preoperative ultrasound showed a median renal pelvis diameter of 34.5 mm. Median operating time was 235 min, and median hospital stay 5.5 days. Median renal pelvis diameter decreased in all patients (13.5 mm). CONCLUSIONS: Laparoscopy is an effective procedure for UPJO correction in children, although operating times are still long.

[Salivary calculi in children]. / Litiasis salival en la infancia.

UNLABELLED: The main salivary glands are the submaxillary, sublingual and parotid glands. Infectious and tumoral conditions are prominent in the parotid gland whilst calculi are in submaxillary and sublingual glands. METHODS. Medical record review of 18 cases with a diagnosis of salivary calculi over a 13 year period. Data collected consisted in, clinical presentation, ultrasound (US), sialography (SG) and computarized tomography (CT), and treatment. RESULTS: 13 male and 5 female. Mean age was 7.2 years. All of them presented with pain and tenderness. Parotid gland was affected in 10 cases. An infectious cause for calculi was found in 7 while 3 presented calculi with no underlying infectious cause. Submaxillary gland was affected in 6 and sublingual in 2. No infectious condition was associated to submaxillary and sublingual calculi. Surgical treatment consisted in duct canalization for calculi removal and was performed in all patients after initial treatment with antibiotics. Neither complications nor relapse was found after surgical removal. CONCLUSIONS: Diagnosis of salivary calculi is made by clinical symptoms and imaging exams. Treatment is surgical and has to be performed after medical treatment for infection and inflamation.