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Understanding the physico-chemistry related to cristalline pathologies constitutes a challenge in several medical specialities such as nephrology, dermatology or oncology. Regarding nephrology, the chemical diversity of concretions such as kidney stones calls for characterization techniques to determine the chemical composition of concretions. The starting point of this contribution is given by Fourier Transform InfraRed (FTIR) spectroscopy which is routinely used at the hospital to determine the chemical composition of kidney stones as well as ectopic calcifications present in kidney biopsy. For kidney stones, the quantity of sample is sufficient to perform a significant analysis through classical FTIR. For ectopic calcifications, $\mu $FTIR can be inefficient in the case of $\mu $calcification in the tissue when their size is less than 10 $\mu $m. For such samples, Optical PhotoThermal IR (OPT-IR) spectroscopy may constitute a way to overcome this experimental difficulty through the acquisition of IR spectrum with a spatial resolution close to 500 nm.To illustrate such opportunity, we first compare the IR spectrum acquired with a classical experimental set-up related to classical IR spectroscopy to IR spectrum collected with a OPT-IR one for different compounds namely calcium oxalate monohydrate, calcium oxalate dehydrate, calcium phosphate apatite and magnesium ammonium phosphate hexahydrate. Such comparison helps us to assess specificity of OPT-IR. Then, we consider several pathological calcifications associated to hyperoxaluria, adenine phosphoribosyltransferase (APRT) deficiency or the presence of Randall’s plaque. We will see that the nanometer spatial resolution constitutes a major advantage versus a micrometre one. Also, in the case of Randall’s plaque, we show that OPT-IR can determine the chemical composition of microscopic concretion without any kind of preparation. Such experimental fact is clearly a major advantage. Finally, we also extended this first investigation in nephrology by considering breast calcifications. In that case, if the number of chemical phases is quite low compared to the number of chemical phases identified in ectopic calcifications present in kidney (four instead of 24), the challenge is related to the possibility to distinguish between the different calcium phosphate namely amorphous carbonated calcium phosphate, CA and whitlockite.The complete set of data indicates the limitations and the advantages of OPT-IR spectroscopy.

Stone analysis is a critical part of the clinical characterization of urolithiasis. This article reviews the strengths and limitations of micro CT in the analysis of stones. Using micro CT alone in a series of 757 stone specimens, micro CT identified the 458 majority calcium oxalate specimens with a sensitivity of 99.6% and specificity of 95.3%. Micro CT alone was also successful in identifying majority apatite, brushite, uric acid, and struvite stones. For some minor minerals—such as apatite in calcium oxalate or calcium salts in uric acid stones—micro CT enables the detection of minute quantities well below 1%. The addition of a standard for calibrating X-ray attenuation values improves the ability of micro CT to identify common stone minerals. The three-dimensional nature of micro CT also allows for the visualization of surface features in stones, which is valuable for the study of stone formation.

Kidney stone disease causes significant morbidity and increases health care utilization. In this work, we decipher the cellular and molecular niche of the human renal papilla in patients with calcium oxalate (CaOx) stone disease and healthy subjects. In addition to identifying cell types important in papillary physiology, we characterize collecting duct cell subtypes and an undifferentiated epithelial cell type that was more prevalent in stone patients. Despite the focal nature of mineral deposition in nephrolithiasis, we uncover a global injury signature characterized by immune activation, oxidative stress and extracellular matrix remodeling. We also identify the association of MMP7 and MMP9 expression with stone disease and mineral deposition, respectively. MMP7 and MMP9 are significantly increased in the urine of patients with CaOx stone disease, and their levels correlate with disease activity. Our results define the spatial molecular landscape and specific pathways contributing to stone-mediated injury in the human papilla and identify associated urinary biomarkers.

OBJECTIVE: The objective of this study is to determine if Aquablation therapy can maintain its effectiveness in treating men with lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) with large-volume (80-150 cc) prostates at 3 years. SUBJECTS AND METHODS: One hundred one men with moderate-to-severe BPH symptoms and prostate volumes between 80 and 150 cc were enrolled in a prospective, nonrandomized, multicenter, international clinical trial in late 2017. Baseline, procedural, and follow-up parameters were recorded at baseline and scheduled postoperative visits. IPSS, Qmax, and treatment failure are reported at 3 years. RESULTS: The mean prostate volume was 107 cc (range 80-150). Mean IPSS improved from 23.2 at baseline to 6.5 at 3 years (16.3-point improvement, p

Objective: We aim to report the learning curve and experience performing holmium laser enucleation of the prostate (HoLEP) from a resident standpoint trained at a tertiary high-volume center. Methods: An electronic survey was distributed to 10 surveyees that included recently graduated chief residents trained at Indiana University in the past 3 years i.e., between 2020 and 2022 with a 100% response rate. The questionnaire focused on HoLEP training experience based on a recently established mentorship curriculum in training the residents through each individual step of the surgery. Results: The average learning curve for performing HoLEP was reported to be greater than 25 cases with 50% of the residents reporting >50 cases to master the technique. The surgical difficulty of steps of the HoLEP were rated on a subjective scale of 1–5: 1 = very easy, 2 = easy, 3 = neutral, 4 = hard, and 5 = very hard. The common challenging steps in decreasing the order of difficulty as reported are performing apical enucleation, joining anterior and posterior planes, and dividing anterior commissure with a mean rating of 3.5, 3.1, and 3.1, respectively. The most difficult aspect of the surgery to master was performing apical dissection (60%). Comparing operative parameters for HoLEP with transurethral resection of the prostate in aspects of resection volume and times, 70% of candidates reported it better for HoLEP whereas 20% had similar times for both procedures. A total of 90% of the residents felt confident to offer HoLEP as part of their practice without the need for any further training. Regarding the initial challenge of including HoLEP surgery in practice, the majority (60%) reported difficulty with equipment set up in their practice while 20% reported difficulty maintaining efficient operating room (OR) times and turnover. Conclusion: We believe HoLEP can be performed immediately after residency training and incorporated into practice with high volume, repeated exposure to HoLEP surgery throughout residency based on study results. The average learning curve reported for performing HoLEP was greater than 25 cases. [ABSTRACT FROM AUTHOR]

ObjectiveThis study was conducted to assess the reliability and precision of an endoscopic grading scale to identify renal papillary abnormalities across a spectrum of equipment, locations, graders, and patients.Materials and methodsIntra- and interobserver reliability of the papillary grading system was assessed using weighted kappa scoring among 4 graders reviewing a single renal papilla from 50 separate patients on 2 occasions. Grading was then applied to a cohort of patients undergoing endoscopic stone removal procedures at two centers. Patient factors were compared with papillary scores on the level of the papilla, kidney, and patient.ResultsGraders achieved substantial (kappa >0.6) intra- and inter-rater reliability in scored domains of ductal plugging, surface pitting, and loss of contour. Agreement for Randall's Plaque (RP) was moderate. Papillary scoring was then performed for 76 patients (89 kidneys, 533 papillae). A significant association was discovered between pitting and RP that held both within and across institutions. A general linear model was then created to further assess this association and it was found that RP score was a highly significant independent correlate of pitting score (F = 7.1; p

Background and purposePercutaneous nephrolithotomy (PCNL) traditionally necessitates the placement of a nephrostomy tube at the conclusion of the surgical procedure. Although tubeless PCNL has become more popular, patients with complex problems still need traditional nephrostomy tube drainage. The goal of this study was to investigate whether patient body mass index (BMI) impacted inadvertent nephrostomy tube dislodgement. Furthermore, we hoped to determine whether nephrostomy tube type impacted tube dislodgement rates.MethodsA retrospective review between 2005 and 2012 of 475 consecutive PCNL cases was undertaken. Patients were categorized based on the type of nephrostomy tube placed. BMI was examined as a continuous variable. The primary outcome of nephrostomy tube dislodgment was determined based on imaging obtained at the time of PCNL and postoperative hospitalization. Logistic regression analysis was then used to adjust for nephrostomy tube type and BMI.ResultsOverall, 24 (5.5%) total patients experienced nephrostomy tube dislodgment postoperatively. The mean BMI for patients experiencing nephrostomy tube dislodgment was 39.7 vs 30.9 for those without tube dislodgment (P