Clinical Research Directory

Impact of Humid-Heat on Gut-Tryptophan-Stone Pathway

Investigating the differences in gut microbiota composition and tryptophan metabolite levels between kidney stone patients and healthy individuals, with special focus on: 1. Comparing the gut microbiota composition between kidney stone patients and healthy controls, with emphasis on analyzing the relative abundance of Lactobacillus salivarius 2. Comparing the differences in tryptophan metabolite levels such as indole-3-carboxylic acid (ICA) and kynurenine (Kyn) in serum between the two groups 3. Exploring the correlation between gut microbiota composition and tryptophan metabolite levels 4. Analyzing the influence of different environmental conditions (seasons, temperature and humidity) on gut microbiota and metabolite levels

New Laser and Suction Sheath for Kidney Stone Treatment

The goal of this clinical trial is to learn if the combination of super pulsed thulium fiber laser (sTFL) with a flexible negative pressure suction sheath is more effective and safer than sTFL with a conventional sheath in treating kidney stones and/or ureteral stones. The main questions it aims to answer are: Does the sTFL with a flexible negative pressure suction sheath have a higher stone - free rate than the sTFL with a conventional sheath? Does the sTFL with a flexible negative pressure suction sheath have fewer complications than the sTFL with a conventional sheath? Researchers will compare the two treatment groups to see if there are differences in stone - free rate and complication rates. Participants will: Undergo ureteroscopic lithotripsy surgery. In the experimental group, have a flexible negative pressure suction sheath inserted along a guidewire to the stone site under general anesthesia, then have a ureteroscope inserted through the sheath to the stone site, and have the stone fragmented by sTFL with a power setting of 0.8J and a frequency of 12 - 20Hz while the fragments are removed by negative pressure suction. In the control group, have a conventional sheath inserted to the upper ureter or the ureteropelvic junction under general anesthesia, then have a ureteroscope inserted through the sheath to the stone site, and have the stone fragmented by sTFL with a power setting of 0.8J and a frequency of 12 - 20Hz and the fragments removed by a stone basket.

Comparison of Mirabegron and Tamsulosin for Ureteral Stone Expulsion

This randomized controlled trial compares the efficacy and safety of four treatment strategies for ureteral stone expulsion: Mirabegron alone, Tamsulosin alone, a combination of both, and standard conservative care. Participants diagnosed with ureteral stones will be randomly assigned to one of these four groups. The primary objective is to evaluate the stone expulsion rate within 4 weeks. The study also assesses time to expulsion, pain intensity, analgesic use, and potential side effects.

Methocarbamol vs Oxybutynin for Management of Pain and Discomfort S/P Ureteroscopy Procedure

Stone disease is a common condition, affecting approximately 9% of Americans in 2007. It causes great morbidity and is also a costly condition, estimated to cost the US healthcare system approximately 3.79 billion dollars in 2007. Ureteroscopy (URS) is the most commonly performed surgical treatment for upper tract stone disease. Ureteral stenting is a common practice after ureteroscopy and placed in \~75% of cases to prevent ureteral edema and renal obstruction. Unfortunately, ureteral stenting can be very painful and has been shown to increase the rate of emergency room visits. Many strategies have been attempted to decrease pain with ureteral stenting including modification of stent material and designs, but efforts so far have been unsuccessful in decreasing stent-related morbidity. Stent-related morbidity is hypothesized to be secondary to irritation of ureteral/bladder mucosa and muscle. Analgesics such as alpha blockers and NSAIDs have been shown to reduce stent morbidity. Anticholinergic drugs are also utilized as they decrease bladder spasms and, therefore, are hypothesized to reduce stent irritation. However, the evidence for anticholinergics has been conflicting. Anticholinergics also have a serious side effect profile including dry mouth, dry eyes, constipation, urinary retention, blurred vision, and even dementia. Some authors even hypothesize that these side effects may offset any purported benefits the anticholinergics provide for stent-morbidity. Methocarbamol is anti-spasmodic muscle relaxant that is believed to work by acting on central neurons and possibly by blocking sodium channels. Given that anticholinergics have many side effects and questionable efficacy, the investigators hypothesize that methocarbamol may achieve superior analgesia for stent morbidity and stent-related bladder spasms. Oxybutynin is used for the treatment of overactive bladder. The rationale is that the oxybutynin relaxes the muscles in the bladder to help decrease problems of urgency and frequent urination caused by the urinary stent irritation. Since anticholinergics have multiple side effects, finding an equally efficacious alternative with less side effects is highly desirable. This study will evaluate the clinical and demographic factors of patients undergoing ureteroscopy and treated postoperatively with methocarbamol vs. oxybutynin for stent-related morbidity. Additionally, the study will aim to understand the postoperative outcomes and complication rates of patients discharged with methocarbamol vs. oxybutynin after ureteroscopy with a ureteral stent in place.

Intraoperative Assessment of of Burst Wave Lithotripsy (BWL)

Burst Wave Lithotripsy (BWL) is a novel method of urinary stone fragmentation that uses multi-cycle bursts of low amplitude ultrasound to induce stone fracture. This is in contrast to traditional extracorporeal shock wave lithotripsy (SWL), which employs a brief single compression/tensile cycle of high amplitude (shock) waves to achieve stone fracture. This is a single-arm feasibility study to test the ability of BWL to comminute (fragment) stones in humans.