Comparative Analyses and Ablation Efficiency of Thulium Fiber Laser by Stone Composition.

PURPOSE: There are limited data on ablation effects of thulium fiber laser (TFL) settings with varying stone composition. Similarly, little is known surrounding the photothermal effects of TFL lithotripsy regarding the chemical and structural changes after visible char formation. We aim to understand the TFL's ablative efficiency across various stone types and laser settings, while simultaneously investigating the photothermal effects of TFL lithotripsy. MATERIALS AND METHODS: Human specimens of calcium oxalate monohydrate, calcium oxalate dihydrate, uric acid, struvite, cystine, carbonate apatite, and brushite stones were ablated using 13 prespecified settings with the Coloplast TFL Drive. Pre- and postablation mass, ablation time, and total energy were recorded. Qualitative ablative observations were recorded at 1-minute intervals with photographs and gross description. Samples were analyzed with Fourier-transform infrared spectroscopy pre- and postablation and electron microscopy postablation to assess the photothermal effects of TFL. RESULTS: Across all settings and stone types, 0.05 J × 1000 Hz was the best numerically efficient ablation setting. When selected for more clinically relevant laser settings (ie, 10-20 W), 0.2 J × 100 Hz, short pulse was the most numerically efficient setting for calcium oxalate dihydrate, cystine, and struvite stones. Calcium oxalate monohydrate ablated with the best numerical efficiency at 0.4 J × 40 Hz, short pulse. Uric acid and carbonate apatite stones ablated with the best numerical efficiency at 0.3 J × 60 Hz, short pulse. Brushite stones ablated with the best numerical efficiency at 0.5 J × 30 Hz, short pulse. Pulse duration impacted ablation effectiveness greatly with 6/8 (75%) of inadequate ablations occurring in medium or long pulse settings. The average percent of mass lost during ablation was 57%; cystine stones averaged the highest percent mass lost at 71%. Charring was observed in 36/91 (40%) specimens. Charring was most often seen in uric acid, cystine, and brushite stones across all laser settings. Electron microscopy of char demonstrated a porous melting effect different to that of brittle fracture. Fourier-transform infrared spectroscopy of brushite char demonstrated a chemical composition change to amorphous calcium phosphate. CONCLUSIONS: We describe the optimal ablation settings based on stone composition, which may guide urologists towards more stone-specific care when using thulium laser for treating renal stones (lower energy settings would be safer for ureteral stones). For patients with unknown stone composition, lasers can be preset to target common stone types or adjusted based on visual cues. We recommend using short pulse for all TFL lithotripsy of calculi and altering the settings based on visual cues and efficiency to minimize the charring, an effect which can make the stone refractory to further dusting and fragmentation.

Mediastinal irradiation and valvular heart disease.

Anticancer therapy has the potential to cause unwanted cardiovascular side effects. Utilization of radiation therapy to treat tumors near the heart can result in radiation-induced valvular heart disease among other cardiovascular pathologies. The aim of this review is to describe the epidemiology, pathophysiology, risk prediction, non-invasive imaging modalities and management of radiation-induced valvular heart disease with a focus on pre-operative risk assessment and contemporary treatment options.

Harnessing the epic electronic medical record to track indwelling ureteral stents in a pediatric population.

INTRODUCTION: Retention of indwelling ureteral stents due to loss to follow-up can result in significant harm to patients, often requiring multiple trips to the operating room. Despite widespread use of electronic medical records, there are few standardized options for urologists to track ureteral stents and no data on the rate of retained stents in a pediatric population. OBJECTIVE: This pilot quality improvement project aims to: 1) develop a simple process to track indwelling ureteral stents using the Epic electronic medical record and 2) determine the incidence of forgotten stents in a pediatric population. METHODS: We identified that operating room staff scan a barcode for ureteral stents at the time of surgery to log the stent as "Implanted" in the patient's medical record. The stent can later be marked as "Explanted" at the time of removal. A report was designed within Epic to identify all patients with a ureteral stent implanted from April 2014 to June 2019 at our hospital. We reviewed the records of patients whose stents had never been marked as "Explanted" to determine if any had a retained stent. A workflow was then designed to ensure staff would mark stents as "Explanted" at the time of removal and to periodically run the report within Epic to ensure that all patients with ureteral stents in place have appropriate follow-up. RESULTS: Our report identified 152 ureteral stents with a status of "Implanted". 3 patients did not have evidence of stent removal documented in their medical record. Follow up with these patients revealed stent removal at an outside location. DISCUSSION: Current approaches to stent tracking are laborious with limitations to adherence. The Epic software directly incorporates stent tracking into the individual patient chart allowing for easy implementation and follow up. Our study revealed no retained stents in our pediatric population. CONCLUSIONS: All patients with ureteral stents placed at a single institution over a 5-year period were easily identified using an automated Epic report. Through this report, we will prevent morbidity associated with stent retention. This technique could easily be implemented at other hospital systems that use Epic, and similar reporting tools could be designed within other electronic medical record systems. The incidence of ureteral stent retention in the pediatric population is likely significantly lower than for their adult counterparts.

Cushing syndrome cardiomyopathy: an unusual manifestation of small-cell lung cancer.

Cushing syndrome is a rare cause of dilated cardiomyopathy and heart failure with reduced ejection fraction. Cases describing this association are scarce. We describe a patient presenting with acute heart failure, new cardiomyopathy, refractory hypokalaemia, severe hyperglycaemia, and uncontrolled hypertension who was found to have hypercortisolism secondary to an ectopic adrenocorticotropic hormone-secreting primary lung neoplasm. This case highlights the effects of hypercortisolism on the myocardium. The finding of a non-dilated cardiomyopathy in this case is unique because the majority of previously reported Cushing syndrome cardiomyopathy cases have described left ventricular dilatation or significant left ventricular hypertrophy. In addition, small-cell lung cancer with adrenocorticotropic hormone production causing Cushing syndrome cardiomyopathy is rare.

Isolated DHEAS production by an adrenal neoplasm: Clinical, biochemical and pathologic characteristics.

Androgen-secreting adrenal neoplasms have a low incidence, usually secrete multiple hormones, and may present with hirsutism, acne, and alopecia. We report an exceedingly rare case of a purely dehydroepiandrosterone-sulfate (DHEA-S) secreting adrenal neoplasm found incidentally on cross sectional imaging. The clinical, biochemical, and pathologic findings of this neoplasm are described.