Emergency Department Imaging Modality Effect on Surgical Management of Nephrolithiasis: A Multicenter, Randomized Clinical Trial

Abstract

Purpose: In the emergency department ultrasonography is emerging as an alternative to computerized tomography for diagnosing patients with nephrolithiasis. In this multicenter randomized clinical trial we examined rates of urological referral and intervention to elucidate whether the initial diagnostic imaging modality affected the management of nephrolithiasis. Materials and Methods: Patients 18 to 76 years old who presented to the emergency department with renal colic across 15 diverse treatment centers were randomized to receive abdominal ultrasonography by an emergency department physician or a radiologist, or abdominal computerized tomography. We analyzed the 90-day followup for patients diagnosed with nephrolithiasis to assess subsequent urological evaluation, procedure type and time to intervention. Results: Of 1,666 patients diagnosed with nephrolithiasis in the emergency department 241 (14.5%) had a consultation with urology at initial presentation, 503 (30%) saw a urologist in followup and 192 (12%) underwent at least 1 urological procedure. Median time to outpatient procedure and type of procedure performed did not vary significantly among imaging groups. Most patients (78%) had computerized tomography performed before elective intervention. Patients with ultrasonography performed by an emergency department physician were 2.6 times more likely to undergo computerized tomography before intervention than those who had ultrasonography performed by a radiologist. Conclusions: Patients undergoing a urological intervention who had ultrasonography as initial imaging do not experience a significant delay to intervention or different procedure types, but the majority ultimately undergoes computerized tomography before surgery. Formal ultrasonography by a radiologist may encourage less computerized tomography preoperatively.

Bilateral ureterolithiasis: A true positive and false negative PoCUS exam in a patient with renal colic

“…One possibility is diagnostic ultrasound performed by radiology, which is more sensitive than PoCUS. 13 However, in many centres including ours, a radiology performed ultrasound is only available at 0800 to 1600 hours, so this is not an option for patients presenting outside of this timeframe. KUB X-ray is also reasonable considering its lower radiation dose, 0.7 mSV compared to 10-12 mSV with CT and 1-3 mSV with low dose CT. 14 However, it is less sensitive and may not exclude the need for further imaging, so CT is the best available imaging modality to confirm a diagnosis.…”

Aktualisierung der S2k-Leitlinie zur Diagnostik, Therapie und Metaphylaxe der Urolithiasis (AWMF Registernummer 043-025)

“…Der Ultraschall (US) stellt sowohl in der Notfall-als auch in der Routinediagnostik die erste Wahl dar [4]. Die sonographische Darstellung des Harntrakts ist sicher, kann den Aufenthalt in der Notaufnahme signifikant verkürzen [5] und führt zudem zu keinem relevanten Zeitverlust bis zu einer eventuellen Intervention [6,7]. Der Farbdopplerultraschall eignet sich in der akuten Kolik für die initiale Diagnose eines Harnleitersteins und ist mit den Ergebnissen des Steinsuch-CT vergleichbar [8,9].…”

Imaging in Suspected Renal Colic: Systematic Review of the Literature and Multispecialty Consensus

“…A multicenter, pragmatic, comparative effectiveness trial published in 2014 randomized over 2,500 patients with suspected kidney stones to POCUS, RPUS, or CT and concluded that ultrasound (RPUS or POCUS) is a safe approach for the evaluation of ureterolithiasis, noting that "return emergency department visits, hospitalizations, and diagnostic accuracy did not differ significantly Journal of the American College of Radiology among the groups" [5]. RPUS when compared with POCUS was less likely to result in subsequent CT (27% with RPUS versus 41% with POCUS) [5,29].The study showed a small but significant longer length of emergency department stay for RPUS than either the POCUS or CT groups (7.0 hours versus 6.3 and 6.4 hours, respectively) [5].…”

“…both diagnostic accuracy and patient treatment will be unchanged" [35]. A secondary analysis of the large prospective multicenter randomized trial comparing ultrasound to CT as an initial imaging modality found that there was no significant difference between timing of urologic intervention based on the initial imaging modality [29].…”