ABSTRACT
Determination of optic nerve sheath diameter (ONSD) with transbulbar sonography has become an easily accessible and time-effective tool in the assessment of increased intracranial pressure. The aim of our study was to evaluate the usefulness of transbulbar sonography in the initial diagnosis and in follow-up examinations of children and adolescents with the diagnosis of pseudotumor cerebri syndrome (PTCS). We retrospectively reviewed imaging results of 24 patients aged 0.75-17 years with PTCS. Serial transbulbar sonography examinations were performed between 2011 and 2021. Sonographic evaluation included the ONSD, papilledema and subarachnoid space. 240 sonographic measurements taken at 108 time points in 17 patients met the inclusion criteria. All patients underwent serial lumbar punctures and routine fundoscopy in close relation to transbulbar sonography. We found that ONSD values remained high in all patients. The longest follow-up period was dated 2498 days (6.84 years) after initial diagnosis. Papilledema resolved in close correlation to fundoscopy normalization. In 16/17 patients the subarachnoid space remained cystic in appearance. These findings were independent of clinical symptoms and lumbar puncture opening pressure. We conclude that transbulbar sonography is a useful diagnostic tool in the initial diagnostic workup of children with PTCS. On follow-up however ONSD values and the cystic transformation of the subarachnoid space remained pathologic in the majority of cases while papilledema resolved parallel to fundoscopy findings. Serial measurements of ONSD are therefore of limited value in the follow-up of patients with PTCS and cannot be considered a reliable tool in subsequent therapeutic decisions.
