History Of Stent Placement Research Articles

FREQUENCY AND PREDICTORS OF ACCESS FAILURE IN PATIENTS UNDERGOING URETERORENOSCOPY FOR UPPER URINARY TRACT CALCULI

Objective: To determine the frequency and factors responsible for access failure during primary ureteroscopy (URS).
 Study Design: Cross-sectional study.
 Place and Duration of Study: Aga Khan University, Karachi Pakistan, from Jan to Jul 2019.
 Methodology: All patients undergoing Ureterorenoscopy for upper urinary tract urolithiasis were included. Ureterorenoscopy was performed with either semi rigid, rigid digital or fiber opticflexible ureterorenoscope as appropriate. Data was collected for demographics, history of stone passage, previous Ureterorenoscopy /double J stenting and history of stent placement. Preoperative imaging reviewed for stone location, size and number. Level of access failure (proximal/mid/distal ureter) was noted. Post-operative complications and need of ancillary procedure was noted.
 Results: We included 250 participants undergoing ureteroscopy for the upper urinary tract calculi. Mean age of the patients was 44.15 ± 13.76 years. Mean stone size was 9.12 ± 4.23mm. Overall access failure rate was found to be 8% (20/250), all required an ancillary procedure. None of the patients with previous history of endoscopic intervention or stone passage had access failure. On univariate and multivariate analysis only stone location was found to be significant factor predicting access failure.
 Conclusion: Failure to access is not uncommon during primary ureteroscopy. Access failure is more common in proximal ureteral stone and in patients with no previous episode of ureteral stones and procedure. Information from this study will help in counseling patients’ pre-operatively and may be a guide to urologists on pre stenting of selected patients at high risk of access failure.

A New Contrast Enhancement Protocol for Subtraction Coronary Computed Tomography Requiring a Short Breath-Holding Time

We have developed a new contrast enhancement protocol for subtraction coronary computed tomography (SCCTA) requiring a short breath-holding time. In the protocol, test and main boluses were sequentially and automatically injected, and correct timings for pre-contrast and contrast-enhanced scans for main bolus were automatically determined only by the test bolus tracking. Combined with a fixed short main bolus injection for 7 seconds, the breath-holding time was shortened as possible. The purpose of this study was to evaluate whether use of this new protocol produced adequate quality images, taking into account calcified lesions and in-stent lumens. Patients (n = 127) with calcium scores of >400 Agatston units or a history of stent placement were enrolled. Breath-holding times were recorded, and image quality was visually evaluated by two observers. The mean ± standard deviation breath-holding time was 13.2 ± 0.6 seconds. The mean ± SD computed tomography (CT) number of coronary arteries for the pre-contrast scan was sufficiently low [99.2 ± 32.2 Hounsfield units (HU)] and, simultaneously, that for SCCTA was 367.0 ± 77.2 HU. The rate of segments evaluated as unreadable was sufficiently low (3.8%). Use of the SCCTA protocol was efficient and allowed for a shorter breath-holding time and adequate diagnostic accuracy of SCCTA images, including images of calcified and stent implantation segments.

Infective coronary arteritis: a pathological analysis at autopsy

Coronary artery disease, one of the leading causes of worldwide adult mortality, is most commonly atherosclerotic in pathogenesis. Nonatherosclerotic etiologies are quite rare. In the latter category, infective arteritis or infective vasculitis of the coronary arteries is a very rare but well-recognized subtype, usually discovered at autopsy. In this article, we present the clinicopathologic necropsy data of 10 patients in whom infective coronary arteritis was the leading cause of death. Among the 10 cases, the male/female ratio was 6:4, and with the exception of a 2-year-old female child, all the other patients were adults with an age range of 26 to 59 years. Of the 10 cases, 6 had infective endocarditis along with history of rheumatic heart disease in 3 patients, whereas 2 other patients had strong clinical suspicion of bacteremia or septicemia. The remaining 2 cases had preexisting coronary atherosclerosis with a history of stent placement in 1 of them. All our cases showed on histopathology acute obliterative inflammatory infiltrate consisting mainly of neutrophils along with bacterial colonies (in most of them) involving the epicardial and intramural coronary arteries. To the best of our knowledge, this is the largest series of infective coronary arteritis to be reported in the world.