Outcomes of delayed CSF diversion protocol in Infants with lumbosacral myelomeningocele: impact of timing of presentation on hydrocephalus development and postoperative complications.

BACKGROUND: Myelomeningocele (MMC) remains one of the most common congenital central nervous system anomalies, with Iraq reporting notably higher prevalence rates (31.9 per 10,000 births) compared to global standards. The timing of presentation and cleanliness of the defect site may significantly impact outcomes in these vulnerable infants. OBJECTIVE: To evaluate the efficacy and safety of a delayed cerebrospinal fluid (CSF) diversion protocol following primary back repair in infants with lumbosacral myelomeningocele and to assess the impact of timing of hospital presentation on clinical outcomes and complication rates. METHODS: This prospective single-arm interventional cohort study enrolled 186 consecutive newborns with lumbosacral MMC between February 2021 and April 2024 at two neurosurgical centers in Iraq. Patients were categorized into two groups based on timing of presentation: clean lesion group (n = 117, presented within 24 h of birth at hospitals) and contaminated lesion group (n = 69, presented 2-7 days after birth). All underwent primary back repair with deliberately delayed CSF diversion. Patients were followed for 12 months for the development of hydrocephalus and for postshunting possible complications. RESULTS: Overall, 143 of 186 patients (76.8%) required VP shunt placement, which is lower than the globally reported rate of 82-90%. The shunt-free rate was significantly higher in the clean lesion group (26.4%, 31/117) compared to the contaminated lesion group (17.4%, 12/69). Postoperative complications were more frequent in the contaminated lesion group, including higher rates of wound infections (26.3% vs. 15.1%), shunt infections (19.3% vs. 8.1%), and shunt malfunctions (24.6% vs. 16.3%). The clean lesion group underwent VP shunt placement earlier (median 11-16 days postrepair) compared to variable timing in the contaminated lesion group (5-29 days). CONCLUSION: Delayed CSF diversion following MMC repair appears feasible and may reduce overall shunt dependency rates. Early hospital presentation within 24 h of birth is associated with cleaner defects, lower infection rates, and fewer postoperative complications. These findings support the importance of optimizing referral systems and community health education to ensure timely presentation of newborns with MMC.