OBJECTIVE: The authors aimed to describe a low-cost and easily reproducible alteration of the Bruner and Tulipan procedure to preserve uterine muscular fibers. They conducted a retrospective cohort study of 10 pregnant women whose fetuses developed lumbosacral myelomeningocele (MM). The MM was repaired through a fetal neurosurgical procedure using a tubular single-port endoscope-assisted technique. METHODS: This study was conducted at the Santa Joana Hospital and São Paulo Hospital between January 2020 and June 2023. The procedure consisted of tubular retraction of circular fibers from the uterine body without excision of the uterine wall. Tubular devices with progressively larger diameters were used for retraction without cutting the uterine muscular fibers, and a 25-mm-diameter tubular retractor was used to allow endoscope-assisted closure of the MM using microsurgical techniques. RESULTS: The average birth age was 36 weeks 3 days. Defect repair was possible in all cases. The mean surgical time was 130 minutes. Two of the patients developed hydrocephalus. One patient underwent a ventriculoperitoneal shunt, and the other underwent endoscopic third ventriculostomy with choroid plexus coagulation. CONCLUSIONS: This procedure avoids excision of the uterine wall, promotes a workspace for microsurgical techniques assisted by endoscopy, and is possibly the first step for future single-port correction using robotic techniques.