The study revealed that a high proportion of IIH patients responded to medical treatment including weight reduction program with or without lumbar puncture and only 13.2% needed LPS. Patients needed neurosurgical intervention experienced rapid disease progression with short HPT (fulminant IIH). This finding is passing with that of Hoffmann and colleagues 2018 [12] and Mulroy and colleagues 2018 [13] who stated that most IIH patients have a relatively benign, self-limiting course except in those with rapid progressive course and fast diminution of vision who carry worse visual outcomes and necessitate rapid CSF shunting.
The study showed that the presence of ANP, TVO, or very high opening CSF pressure during baseline assessment are not indicators of surgery and a big proportion of them underwent subsequent regressive course. These results are passing with the studies of Agarwal and colleagues 2017 [2] and Berezovsky and colleagues 2017 [14] who stated that ANP, TVO, and high CSF pressure are not predictors of poor visual outcome in IIH, but follow-up of cases is needed to diagnose progressive cases.
The study declared different vulnerability of the ON to external compression by the elevated ICP evidenced by the non-significant correlations between CSF pressure and each of papilledema grade, MD-VFE, average OCT–RNFL thickness, and asymmetry of these parameters in a sector of patients (Fig. 2). These results are in harmony with that of Markey and colleagues 2016 [15] who stated that the grades of papilledema are sometimes not proportional with the degrees of visual impairments which makes it an imprecise parameter to follow-up IIH patients.
The results of this study showed that obesity is an important IIH predisposing factor especially in post-pubertal females and weight reduction is an effective disease-modifying factor that helps in treatment IIH. Fahmy and colleagues 2016 [16] and Agarwal and colleagues 2017 [2] are keeping with these results and stated that IIH might exhibit high intra-abdominal pressures due to increased visceral obesity which may be transmitted intracranially in the presence of incompetent internal jugular vein valve. By contrast to these results, Biousse 2012 [17] stated that the degrees of obesity are not associated with higher incidence of PVD, but he considered that higher degree of obesity is a predictor of subsequent visual decline possibly due to higher incidence of obstructive sleep apnea among his studied patients.
The study revealed that brain MRI/MRV of IIH are commonly associated with EST, ON changes (increased ONSD, dilated ON subarachnoid space, and ON tortuosity) and/or transverse sinus stenosis, but these findings are not correlated with the opening CSF pressure and are not predictors of possible subsequent progression or need of LPS. These findings are in harmony with the results of Agarwal and colleagues 2017 [2] who stated that brain MRI/MRV increases the diagnostic certainty of IIH and aid in exclusion of mass lesions, hydrocephalus, and venous sinus thrombosis but are not associated with worse prognosis.
The study showed that childhood onset IIH usually has a relatively benign course and little possibility of progression as all included children had responded to medical treatment. At the same time, there was non-significant sex difference childhood onset IIH which points to the role of gonadal female sex hormones in the pathogenesis of IIH during subsequent pubertal and childbearing periods. This assumption is in harmony with the work of Margeta and colleagues 2015 [18] and Galindo and colleagues 2017 [19] who stated that prepubertal IIH usually has non-significant sex difference, carries a favorable outcome, and infrequent need for surgical intervention.
Transorbital sonographic assessment of the ONSD is an easy, cost-effective non-invasive technique useful in detecting raised ICP [8]. The study showed that ONSD dilatation is a reliable confirmatory diagnostic test for raised ICP due to IIH but has a weak prognostic value as the degree of ONSD was not correlated with the degree of papilledema, and visual field affection as well as possible subsequent PVD. On the other hand, the test is a suitable easy tool to assess post-operative IIH regression and follow-up for possible shunt obstruction as it is the first parameters affected by changes in ICP. These results are in accordance with that of Bekerman and colleagues 2016 [20] who stated that ONSD is a useful test in diagnosis of high ICP, but it needs other additional investigations to quantify its severity. On the contrary, Liu and colleagues 2017 [21] stated that the dilatation of ONSD is proportional with the ICP rise but this difference in results is explained by the inclusion of cases with acute ICP rise due to head trauma or following intracranial surgery rather than gradual elevation by IIH.
Spectral domain OCT is a quick non-invasive technique which uses interferometric analysis of short-coherence-length infrared light to provide depth-resolved imaging of ocular tissues including the choroid, retina, and ON head [22]. The study showed that spectral domain optical coherence tomography (SD-OCT) is an objective, easy, non-invasive confirmatory tool for diagnosis of early papilledema due to IIH and exclude pseudo-papilledema and ON drusen. These results are passing with that of Huang-Link and colleagues 2015 [23] and Markey and colleagues 2016 [15] who stated that SD-OCT is a highly sensitive tool to measure the ON head changes due to IIH including the cup volume, cup/disc ratio, and RNFL thickness. This high accuracy and lower inter-rater reliability make OCT an objective tool to govern the response to treatments and predict possible progression.
The results declared that prolongation of the P100 VEP latency during baseline assessment is a bad prognostic sign and could be considered as a biomarker for subsequent need of LPS. These results are in existence with that of Hartmann and colleagues 2015 [24] who determined that papilledema due to IIH may be associated with some degrees of ON fibers demyelination and subsequent prolongation of the P100 VEP latency which is associated with poor visual outcome.
The study showed that after resolution of papilledema, some patients even in those who underwent LPS showed further subnormal reduction of the average OCT–RNFL thickness which denotes a degree of ON fiber loss during the disease process (Fig. 1b). A big proportion of such patients had history of grade III and IV papilledema. This finding direct us to re-consider the ideal timing of LPS and avoid postponing which may results in irreversible visual affection. This observation is in accordance with the work of Hoffmann and colleagues 2018 [12] and Wall and colleagues 2017 [6] who stated that delayed affection of the central vision in IIH may result in initial misdiagnosis which may result in irreversible visual affection.