# Head Growth and Fundoscopy as Proxies for Intracranial Pressure in Metopic Synostosis Treated Surgically vs Conservatively

## TL;DR

This study finds that both surgical and conservative treatments for metopic synostosis show similar low risks of increased intracranial pressure, suggesting routine surgery may not always be necessary.

## Contribution

The study provides new evidence that surgical intervention may not be essential for most metopic synostosis patients to prevent intracranial pressure.

## Key findings

- Surgically treated patients showed earlier plateauing of head growth compared to conservatively treated patients.
- Signs of increased intracranial pressure were rare and did not differ significantly between the two treatment groups.
- Close monitoring and selective surgery are safe alternatives to routine surgical intervention.

## Abstract

What are the head circumference trajectories and prevalence of signs of increased intracranial pressure (ICP) among patients with metopic synostosis treated conservatively vs surgically?

In this cohort study of 209 patients, surgically treated patients showed earlier plateauing of head growth, while conservatively treated patients demonstrated steady head circumference increases over time. Signs of increased ICP were rare (1.4%-1.9%) and did not differ between the 2 groups

These findings suggest that routine surgery may not be necessary to prevent ICP for most patients with metopic synostosis, supporting close monitoring and individualized treatment decisions.

The risk of increased intracranial pressure (ICP) in metopic synostosis remains poorly defined, leading to uncertainty about the need for routine surgical intervention vs conservative management.

To compare head growth trajectories and the prevalence of signs of increased ICP among patients with metopic synostosis managed surgically or conservatively.

This prospective cohort study included all 209 new patients with single-suture metopic synostosis presenting to Erasmus Medical Center, Rotterdam, the Netherlands, from January 1, 2017, to December 31, 2024. The current analysis included data collection up to July 31, 2025. Patients underwent annual follow-up with head circumference measurement and fundoscopy.

Surgical or conservative management of metopic synostosis determined through shared decision-making between clinicians and parents.

The primary outcome was longitudinal head circumference standard deviation (SD), analyzed using linear mixed models. Secondary outcomes were head growth deflection and papilledema, understood as signs of increased ICP, detected on fundoscopy.

Among 209 patients (78 surgical and 131 conservative; median age at presentation, 4 months [IQR, 2-7 months]; 154 boys [74%]), the median age at last follow-up was 40 months (IQR, 24-61 months). Head circumference SD increased significantly with age in a nonlinear pattern (age spline df = 1; β = 0.87; 95% CI, 0.54-1.21; P < .001; and age spline df = 2; β = 0.73; 95% CI, 0.29-1.16; P < .001). Female sex was associated with higher SD (β = 0.31; 95% CI, 0.03-0.60; P = .03). Surgical treatment was associated with higher initial SD but a significantly flatter growth trajectory over time compared with conservative treatment (β = –1.02; 95% CI, –1.52 to –0.52; P < .001 for interaction age spline and treatment). Severe deformity phenotype was associated with lower SD values compared with mild deformity phenotype (β = –0.39; 95% CI, –0.75 to –0.04; P = .03). Among 158 patients with 2 or more years of follow-up, head growth deflection occurred among 3 patients (1.9%): 2 of 65 (3.1%) in the surgical group and 1 of 93 (1.1%) in the conservative group (P = .57). Papilledema was observed in 3 patients (1.4%): 2 of 78 (2.6%) in the surgical group and 1 of 131 (0.8%) in the conservative group (P = .56). None of these patients required additional surgery.

In this prospective cohort of patients with metopic synostosis, signs of elevated ICP were rare and did not differ between surgical and conservative groups. Although surgery altered head growth trajectories, the low prevalence of ICP-related findings supports close monitoring and selective surgical intervention as safe alternatives to routine surgery.

This cohort study compares head growth trajectories and the prevalence of signs of increased intracranial pressure among patients with metopic synostosis managed surgically vs conservatively.