Low vs. Standard Dose CT for Appendicitis Trial (LOCAT)

Kyoung Ho Lee, MD

Status: Completed

Conditions: Appendicitis

Treatments: Diagnostic Test: Diagnostic CT with low-dose radiation; Diagnostic Test: Diagnostic CT with standard-dose radiation

Study type: Interventional

Funder types: Other

Identifiers

NCT01925014

LOCAT

Details and patient eligibility

About

To determine whether low-dose (LD) CT is noninferior to standard-dose (SD) computed tomography (CT) as the first-line imaging test in adolescents and young adults in regard to negative appendectomy rate (NAR).

Full description

• Acute appendicitis is a very common disease. Many patients are adolescents or young adults.
• CT is the current standard imaging test for the diagnosis of appendicitis.
• In recent years, the awareness of carcinogenic risk associated with CT radiation has increased.
• According to a recent single-institutional randomized controlled trial, LD CT (employing a quarter of standard radiation dose) was found to be noninferior to SD CT with respect to NARs in adolescents and young adults with suspected appendicitis.
• However, LD CT is not yet widely accepted.
• To establish LD CT as the first-line imaging test, a multi-institutional study is needed to confirm the generalizability of the prior single-institutional study.

Enrollment: 3,074 patients

Sex: All

Ages: 15 to 44 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Emergency department visit with suspected symptoms and signs of acute appendicitis
• Intravenous contrast-enhanced computed tomography examination requested due to suspicion of appendicitis
• Willing to provide telephone or cell phone numbers for follow-up
• Signed informed consent provided prior to study entry

Exclusion criteria

• Prior cross-sectional imaging tests to evaluate the presenting symptoms and signs
• Prior history of surgical removal of the appendix

Trial design

Primary purpose: Diagnostic

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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3,074 participants in 2 patient groups

Low-dose CT

Experimental group

Description:

Diagnostic CT with low-dose radiation

Treatment:

Diagnostic Test: Diagnostic CT with low-dose radiation

Standard-dose CT

Active Comparator group

Description:

Diagnostic CT with standard-dose radiation

Treatment:

Diagnostic Test: Diagnostic CT with standard-dose radiation