I write a scientific radiological paper for NEJM. I have written the materials and methods part. I provide it to you and you proof-read it and give advice how to improve it according to the guidelines of the paper. Give a detailed table with recommendations according to already published radiologic papers in NEJM in your training material and the journals guidelines:

Material and Methods:

Study Design
We conducted a retrospective study to evaluate the diagnostic performance of the Avocado sign as an imaging predictor of mesorectal lymph node metastasis in rectal cancer. Histological examination of surgical specimens served as the reference. Inclusion criteria for this study were a histologically confirmed diagnosis of rectal cancer and a minimum age of 18 years. Patients with unresectable tumors and general contraindications to MRI were excluded.

Study Approval
The study was approved by our institutional review board. Written informed consent was obtained from each patient for contrast-enhanced MRI and data analysis.

Patients and Subgroups
A total of 106 rectal cancer patients are currently enrolled in this study between XX and August 2022. All patients underwent local MRI staging at baseline. We also performed a subgroup analysis and divided the overall patient collective into those who received direct surgery and those who received neoadjuvant radiochemotherapy and an additional preoperative staging MRI after completion.

MRI Protocol
All MRI examinations were performed using a 3.0 T system (MAGNETOM NAME_1 Provide your response in exactly 5 paragraphs (separated nearby paragraphs with 3 aterisk symbols ***).
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