Type of study: Descriptive validation study design.

Study population and Sample size: Source of this data are 30 patients in the age group 18 to 100 years who underwent Lumbosacral spine MRI as a part of their medical investigation from March 2023 to September 2024 in the Department of Radiodiagnosis at St. John's Medical College and Hospital, Bangalore.

IEC approval: Institutional Ethics committee approval received (TH78 /2023) 

Consent of participants: Written informed consent from all the participants received.

Sample size: E.C. Ang et al did a study on diagnostic accuracy of 3-Tesla Magnetic Resonance Imaging with 3D T1 Volumetric interpolated breath-hold examination (VIBE) vs Computed Tomography (CT)in pars stress fracture of lumbar spine and found that the sensitivity is around 96%. To estimate 96% sensitivity with 10% absolute precision given a prevalence of 0.99, sample size required for the study is 30 patients. 

Inclusion criteria

Patients who undergo MRI lumbosacral spine in 3T MRI as a part of their medical investigation in the Department of Radiodiagnosis, St. John’s medical college, Bangalore with symptoms like low backache with or without radioculopathy and who are suspected to have spondylolysis on routine MR sequences

Exclusion criteria

• Patients who have undergone spinal and vertebral surgeries
• Patients who have pacemaker implanted
• Patients who have claustrophobia
•  Studies deemed suboptimal due to artifacts
•  Pregnant women (as complementary CT has to be taken which has high radiation exposure).

 METHODS

• The study was conducted in patients in the age group of 18 to 100 years, who are presented with symptoms like severe backache, radiculopathy etc. or have history of trauma who are suspected to have spondylolysis who come for MRI as a part of their medical investigation in Department of Radiodiagnosis, St. John's medical college, Bangalore 
• The imaging was carried out by a 3 Tesla GE MRI machine. LAVA-Flex sequence is also added to the MRI sequences performed in suspected cases of lumbar spondylolysis. 
• These Liver Acceleration Volume Acquisition-Flexible (LAVA-Flex) 3 Tesla Magnetic Resonance Imaging (MRI) studies will retrieved from Picture Archiving and Communication System (PACS) and used to assess bony spine. 
• If the LAVA-Flex MRI images suggest spondylolysis, complementary CT is taken free of cost as routine as usually done at St Johns medical college as a part of patient care and diagnosis was confirmed. 
• Data was analysed using SPSS V.28.  All the categorical data were summarized using frequency and percentages, whereas all continuous data were described using mean and standard deviation based on the distribution.​ The diagnostic accuracy of proposed MRI sequence that is LAVA-Flex was assessed against Computed tomography (CT) findings. Sensitivity, specificity, positive predictive value, negative predictive value was reported with 95% confidence interval. The p value less than 0.05 considered as statistical significance.