When Headache Is Not Just Headache: Two Years of Symptoms and the Value of Ophthalmic Awareness in Undiagnosed Idiopathic Intracranial Hypertension – A Case Report

Abstract

Introduction

Idiopathic intracranial hypertension (IIH) can present with nonspecific symptoms such as chronic headache and dizziness, making diagnosis challenging and often delayed. Ophthalmologic evaluation plays a crucial role in identifying IIH and preventing irreversible visual damage.

Case Presentation

We report a case of a young woman with a 2-year history of persistent headache and dizziness of unknown origin. She was subsequently diagnosed with previously unrecognized IIH following ophthalmic evaluation, including optical coherence tomography, fundus examination, and visual field testing. These findings prompted timely shunt placement, which resulted in marked recovery of the visual fields.

Conclusion

This case highlights the educational value of ophthalmologic awareness and the importance of integrating ocular findings into clinical decision-making, particularly in patients with chronic unexplained headache. It underscores the relevance of prompt initiation of therapy and, when necessary, invasive surgical intervention to prevent lifelong optic nerve damage and poor visual outcomes in a young population.

Introduction

Idiopathic intracranial hypertension (IIH) is a rare condition, mostly seen in young women of reproductive age, and has a strong predisposition in obese patients, with an incidence of 1–2/100,000 per year in the general population and a significantly higher incidence in the obese population 4–21/100,000 per year [1]. Pathophysiology and the reason for a population preference remain unclear. Suggestions have been made of the role of hormonal and metabolic changes and the role of inflammatory adipokines, causing dysregulation of cerebrospinal fluid (CSF) production, reabsorption, and adequate evacuation. Also changes in venous sinus pressure have been noticed. This causes an overflow to the subarachnoid and perivascular space [2, 3].

Patients frequently come to the hospital with loss of vision as first presentation. The main presenting symptoms are blurred vision, diplopia, and headache. The degree of visual loss can differ greatly among patients, going from slight blurring to total visual obscurations [3]. The peripheral eyesight is the most affected, but total vision loss has also been described. These are the principal causes of morbidity, showing different degrees of papilledema at presentation.

One of the few neurologic symptoms is cranial nerve palsy, mostly 6th cranial nerve palsy causing horizontal diplopia in 10–20% of patients, but in rare occasions, other cranial nerves can be involved as well [4]. General symptomatology includes dizziness, nausea, and vomiting, sometimes accompanied by severe headaches, neck stiffness, difficulty walking, (pulsatile) tinnitus in up to 52–61% patients, and depression. Olfactory changes and memory impairment are seen in 20% of patients [4].

The main treatment of IIH is composed of weight loss with a low-sodium diet and lifestyle changes. This in combination with carbonic anhydrase inhibitors has shown a significant improvement of papilledema by reducing the production of CSF by 6–50% [5]. A subcategory of IIH, fulminant IIH, is characterized by severe vision loss within 4 weeks after the onset of symptoms, rapidly progressing over days without a secondary cause. When fulminant IIH is suspected, prompt surgical intervention is necessary to prevent poor visual outcome [6, 7].

With the rising numbers of obesity worldwide, IIH is becoming a more frequent, potentially vision threatening condition. The literature describes mostly a neuroradiologic point of view, elaborating on the changes in ventricle anatomy to slit-like ventricles, changes in neuroimaging like empty sella turcica, distension of the optic nerve sheath, optic nerve tortuosity, and venous sinus stenosis in diagnosing this condition, as well as a neurosurgical point of view with the use of different therapeutic shunts [8]. The goal of our case report was to emphasize the importance of a thorough ophthalmologic examination as a diagnostic objective tool and follow-up of disease progression, as well as the value of interdisciplinary communication to obtain the best outcome for the patient.

Case Report

A 31-year-old woman was referred to us by the peripheral ophthalmologist because of non-resolving papillary edema in both eyes in November 2024. She had been complaining of profound vision loss in the right eye for over 6 months. Feelings of dizziness were already present for 2–3 years. A profound neurological investigation had been performed but did not provide any etiology.

As patient characteristics, we underline Arab ethnicity, height of 1.61 meter, weight of 80 kg, giving a body mass index of 30.9. In her medical history, we retain migraine, gestational diabetes with significant weight gain, and orthostatic hypotension.

First presentation at the external ophthalmologist was in July 2024. Clinical findings at that time included bilateral papilledema, fulminant on the right side, and only inferior optic disc swelling on the left side. The vision at this point was 8/10 in the right eye, 9/10 in the left eye. A visual field examination was not possible at this point because of nausea and losing consciousness during the test.

An MRI in August 2024 showed multiple periventricular lesions, which raised the suspicion of underlying demyelinating disease. However, changes surrounding the nervus opticus and transverse sinuses of the cerebral veins as well as partial empty sella were rather suggestive of IIH.

Follow-up consultation in September 2024 showed an increase in papilledema on both sides. The vision had decreased bilaterally to 5/10 in the right eye and 6/10 in the left eye.

In October 2024, the patient was admitted to hospital with severe headaches. Because multiple sclerosis was not yet ruled out, she received intravenous Medrol in a dosage of 1 g during 3 days at the neurology department. The vision in the left eye had improved to 9/10 again, but nevertheless, a slight increase in papilledema was noted bilaterally. A spine MRI in October 2024 showed no evidence of demyelinating lesions in the spinal cord, ruling out multiple sclerosis as differential diagnosis.

In November 2024, there was, for the first time since July, a slight decrease in papilledema on both sides, most likely because of the recent high dosage of Medrol. The vision had also improved, reaching 7/10 in the right eye and 9/10 in the left eye. However, no clear etiology of sudden vision loss was still found. The patient was therefore referred to our hospital for further investigation.

The vision upon referral was 4/10 in the right eye and 10/10 in the left eye. Biomicroscopy showed a normal anterior eye segment with no intraocular inflammation. Dilated fundoscopic examination showed papilledema grade 1–2 in both eyes, as defined by Frisen’s gradation of papilledema (a visual representation is shown in Fig. 1), slightly more in the right eye. Pupillary reflexes showed a slower pupillary reflex in the right eye, but no evidence for a relative afferent pupillary defect. The Ishihara color test was abnormal in the right eye and normal in the left eye. An automatic 30° visual field examination was performed on both eyes (Fig. 2a), showing concentric narrowing of the visual field in the right eye and normal examination in the left eye.

Fig. 1.

Visual representation of Frisen’s gradation of papilledema.

Fig. 2.

a–d Visual field examination with Octopus 900 (30° dynamic SITA standard).

Optical coherence tomography (OCT) showed a significant swelling of the retinal nerve fiber layer (RNFL) in both eyes, with right eye showing more swelling than the left eye (Fig. 3a, b). At this point, the patient was referred to the department of neurology in our hospital for further investigation.

Fig. 3.

a The average RNFL thickness of the right eye (left) and left eye (right) in November 2024. Retinal nerve fiber thickness right eye: 271 micrometers. Retinal nerve fiber thickness left eye: 150 micrometers. b The RNFL thickness divided into quadrants (upper picture) and clock hours (lower picture) in November 2024. Left column shows the right eye, the right column shows the left eye. c The RNFL thickness of the right eye (left) and left eye (right) in January 2025. Retinal nerve fiber thickness right eye: 105 micrometers. Retinal nerve fiber thickness left eye: 91 micrometers. d The RNFL divided into quadrants (upper picture) and clock hours (lower picture) in January 2025. Left column shows the right eye, the right column shows the left eye. e The RNFL thickness of the right eye (left) and left eye (right) in April 2025. Retinal nerve fiber thickness right eye: 68 micrometers. Retinal nerve fiber thickness left eye: 77 micrometers. f RNFL thickness divided into quadrants (upper picture) and clock hours (lower picture) in April 2025. Left column shows the right eye, and the right column shows the left eye. This shows the evolution of the RNFL to atrophy, more on the right side, beginning stage on the left side.

MRI imaging was repeated and showed multiple white matter lesions, primarily suspicious of demyelinating disease. No white matter lesions were found in the cervical marrow. The changes in the optic nerve and transverse sinuses of the cerebral veins, and partially empty sella sign again raised the suspicion for IIH.

Consequently, a lumbar puncture (LP) was performed in December 2024, showing an opening pressure of 38 cm CSF (<25 cm CSF) [2], normalizing after draining 10 cc of CSF.

When there is uncertainty of the cause of papilledema, it is important to perform a neurologic examination with extra attention to cranial nerve involvement. When a cranial nerve palsy other than cranial nerve VI palsy is present, a secondary cause should be considered. An MRI or, if impossible, at least a CT (followed by MRI if negative) can rule out masses, hydrocephalus, structural lesions, vascular issues, or abnormal meningeal enhancement as a secondary cause. Within the first day after presentation, a CT or MRI venography can rule out cerebral sinus thrombosis. Regarding the lack of these features in our case, we decided on the diagnoses of IIH. Neuroimaging is important and can show a variety of modified characteristics, although not pathognomonic of IIH [7].

When the diagnosis of IIH was made, an oral carbonic anhydrase inhibitor, acetazolamide, was started at a dosage of 2 × 250 mg per day alongwith semaglutide by the endocrinologist. GLP-1 receptor agonists, such as semaglutide, have been associated with significant weight loss, reduced headache frequency, and improvement in visual outcomes, including decreased papilledema in patients with IIH, supporting their potential as adjunctive therapy [9].

The patient was examined the day after the LP because of subjective worsening of the vision, especially in the left eye. The ophthalmologic examination showed a stable visual acuity of 5/10 in the right eye and 9/10 in the left eye. A dilated fundoscopic exam showed an increase in papilledema to grade 3 in the right eye and grade 2 in the left eye.

Automatic 30° visual field examination was again performed (Fig. 2b), revealing an increase in concentric narrowing in the right eye and now with areas of reduced sensitivity in the left eye. Considering the recent findings, the neurosurgeon was immediately contacted to discuss the need for an urgent surgical intervention. A ventriculoperitoneal shunt was placed 2 days after the diagnosis was made.

As part of follow-up, the patient was examined again 2 weeks later. On anamnesis, the vision had improved greatly and the patient was feeling better overall. The vision had normalized to 10/10, with an improvement of the papilledema on both sides, to grade 1 in the right eye and resolution of papilledema with only slight nasal haziness in the left eye. Automatic 30° visual field examination also showed a positive progression in both eyes, even better results than on first presentation (Fig. 2c). OCT presented a substantial diminution of the RNFL thickness in both eyes (Fig. 3c, d).

At the last consultation in April 2025, the patient reported recurrent darkening of vision in the right eye for 1.5 months. As dizziness and headache persisted, the neurologist started treatment with topiramate. On examination, she had a vision of 8.5/10 in the right eye and 10/10 in the left eye.

The visual field examination was stable, although it showed a nasal defect on the right side (Fig. 2d). OCT of the optic nerve showed the evolution of the RNFL to atrophy, secondary to increased intracranial pressure over a longer period of time, mostly in the right eye and also partially in the left eye (shown in Fig. 3e, f). This explains the slightly lower visual acuity in the right eye, again pointing out the importance of prompt treatment. On fundoscopic examination, the optic nerve was fully sharp with normal optic disc cupping. Normal and symmetric pupillary reflexes were restored, with no relative afferent pupillary defect and the Ishihara color test was normal.

Currently, she is being followed up by the neurologist with regular MRI scans at our hospital and has been advised to maintain a healthier and more active lifestyle to lower her BMI and thereby prevent recurrence. Her prognosis now depends on how intensely she is going to adapt her lifestyle and the potential continuing atrophy of the optic nerve.

Discussion

IIH is a growing issue globally. IIH is closely associated, though not exclusively, with obesity, and between 2002 and 2016, there has been an increase in its incidence by 104.3% [10]. Obesity too is a growing health issue worldwide and its prevalence has increased by 200% in the period of 1990–2022, even quadrupled in adolescents [11]. The rising incidence and prevalence of IIH is becoming a more frequent cause of visual impairment in young adults. It is therefore necessary to diagnose and treat these patients before permanent damage occurs. We highlighted the importance of constructive and complimentary interdisciplinary collaboration and communication to obtain the best possible results.

At first, the differential diagnosis had to be made between secondary causes, including migraine, masses, thrombosis, or multiple sclerosis, and IIH. Given the severe vision loss, persistency of the vision loss, and her age, MS was considered most likely. An MRI and negative LP ruled out this diagnosis. The severe headaches were initially misinterpreted as migraine attacks, leading to a significant latency in the diagnosis of IIH and adequate treatment.

The diagnosis of IIH can be made following the recent guidelines of Mollan et al. [7] (shown in Table 1), where the IIH without papilledema is the less severe form with limited visual impairment. Neurologic examination, in combination with ophthalmologic examination and neuroimaging, is mandatory to diagnose IIH and exclude secondary causes. Table 2 shows the different changes that can be seen on MRI with their respective incidence, sensitivity, and specificity [4].

Table 1.

Evaluation, diagnosis, and classification of IIH

​	Evaluation and diagnosis of IIH
Step	Details
Evaluation	1.Papilledema confirmed –Assess visual acuity –Evaluate formal visual fields –Confirm papilledema through dilated fundoscopic examination by an experienced clinician if any doubt 2.Check blood pressure and exclude malignant hypertension 3.Perform brain imaging within 24 h (CT and/or MRI plus venography) to exclude mass lesions or venous sinus thrombosis 4.Perform a lumbar puncture: showing opening cerebrospinal fluid (CSF) pressure >25 cm H2O with normal CSF composition 5.Exclude secondary causes

​	Classification of IIH
Step	If no secondary causes are considered:
Evaluation	1.Fulminant IIH: rapidly deteriorating vision posing a high risk of permanent blindness 2.Typical IIH: –Woman of reproductive age –Body mass index >30 kg/m2 3.Atypical IIH: –Not female, not of reproductive age –Body mass index <30 kg/m2

IIH, idiopathic intracranial hypertension.

Table 2.

Summary of diagnostic criteria for IIH: modified Dandy criteria

Category	Criteria
Required criteria	Papilledema Normal neurological examination except possible cranial nerve involvement Neuroimaging without mass, hydrocephalus, or abnormal meningeal enhancement; MRV recommended unless patient is typical (female, obese) Normal CSF composition Elevated LP opening pressure (≥250 mm CSF adults; ≥280 mm CSF children, or ≥250 mm if nonobese and non-sedated)
Definite PTCS	All required criteria are fulfilled.
Probable PTCS	Criteria A–D present with bilateral papilledema, but CSF opening pressure below diagnostic threshold.
PTCS without papilledema (IIHWOP)	Diagnosis can be made if criteria B–E are met plus unilateral or bilateral abducens palsy.
Suggested PTCS without papilledema or sixth nerve palsy	Criteria B–E must be met and at least three neuroimaging signs present: Empty sella Posterior globe flattening Enlarged perioptic subarachnoid space (±tortuous optic nerve) Transverse venous sinus stenosis

When medical therapy and lifestyle changes fail to alleviate the symptoms and the vision is threatened, immediate surgical intervention is required. Possible treatment options are nerve sheath fenestration or decompression, venous sinus stenting, or CSF diversion. There has been no prospective study to compare these options, but CSF diversion with ventriculoperitoneal, lumboperitoneal, and ventriculoatrial shunting as well as nerve sheath fenestration, to a lesser extent, have been the preferred modalities [12]. In either way, there is a high chance of shunt failure and need for re-operation, with recurrent papilledema and headaches being its first signs. The incidence of shunt failure is lower in the ventriculoperitoneal shunt group, with 18.7% reported failure and up to 67% with ventriculoatrial and lumboperitoneal shunting [13]. Additionally, lumboperitoneal shunts have a 2.5-fold higher chance of needing a shunt revision. Brazis [12] reported a significant decrease in headaches in 95% of patients after shunting, although there was a 20% recurrence rate of headache with a functioning shunt. This contrasts with the reports by Sinclair et al. [14] that stated a persistent low-pressure headache in almost 80% of patients up to 2 years after shunting. In case of persistent headaches, weight loss has been more effective than shunting. Altogether, it underlines their well-deserved place in treatment of patients with IIH.

This case report emphasizes the importance of a thorough ophthalmologic examination with dilated fundoscopic exam, visual field performance, and OCT scan in the diagnosis and follow-up of patients with suspected IIH, especially in the fulminant subtype. A limitation of this case report is the follow-up period of this patient. The follow-up period will reveal if there are any shunt failure or complications in the future.

OCT can objectively monitor and notice small changes in retinal nerve fiber thickness. Hence, during the follow-up, frequent OCT in the beginning is necessary to detect these early changes, even before the patients can notice a change in vision or other symptoms, to avoid any aggravating situations. OCT angiography can be used as an additional tool to check small changes in vessel perfusion and density surrounding the optic nerve to evaluate microvascular damage and recovery [3, 15]. In addition, checking the vision and visual field examination can be helpful in monitoring the success of a ventriculoperitoneal shunt which will detect even a minimal change in the scotoma extent and density. Table 3 shows a suggestion of follow-up interval by Mollan et al. [10], depending on severity and duration.

Table 3.

Follow-up recommendations based on papilledema grade and visual field status

Papilledema grade	Normal	Improving	Stable	Worsening
Atrophic	​	3–6 months	4–6 months	Within 4 weeks
Mild	6 months	3–6 months	3–4 months	Within 4 weeks
Moderate	3–4 months	1–3 months	1–3 months	Within 2 weeks
Severe	​	1–3 months	Within 4 weeks	Within 1 week

In conclusion, an OCT scan and visual field examination will help detect the deterioration of the condition and monitor it so that timely interventions can be undertaken. This approach can prevent permanent vision loss and secondary debilitating morbidity in young patients. Table 4 shows the practice recommendations in Belgium and the Netherlands [16].

Table 4.

Practice recommendations in Belgium and the Netherlands

Recommendation	Key points
Baseline ophthalmic assessment	BCVA, pupils, perimetry, fundus evaluation with fundus photo if available, OCT
Multidisciplinary evaluation	MRI/MRV to rule out secondary causes, lumbar puncture for opening pressure
First-line treatment	Weight loss + acetazolamide (dose adjusted to tolerance/response)
Ophthalmic follow-up	OCT + visual fields for monitoring
Urgent intervention	Hospitalization and surgical options (ONSF or CSF diversion) if rapid/progressive vision loss

Conclusion

We present a case of a 31-year-old woman who was referred to our department with longstanding unexplained headache and dizziness, persistent papilledema, and sudden-onset vision loss of the right eye, rapidly progressing over time. Even though papilledema was noticed previously, the lack of clinical integration and connection to the general symptoms caused a significant delay in diagnosis. This led to the need for an invasive intervention by the neurosurgeon to improve the visual acuity. After the surgery, there was a subjectively and objectively rapid improvement in visual acuity as well as in visual field examination.

Worsening of the vision, changes in OCT imaging, and visual field examination were the main triggers for performing urgent invasive surgery in close collaboration with the department of neurosurgery. These examinations were also a key part and a more objective tool for long-term follow-up after surgery and for evaluating overall improvement.

Statement of Ethics

This case report was approved by the Department of Ophthalmology and Neurology. Written informed consent was obtained from the patient for the case report and publication of the details of their medical case and any accompanying images. The CARE Checklist has been completed by the authors for this case report and attached as online supplementary material (for all online suppl. material, see https://doi.org/10.1159/000550828).

Conflict of Interest Statement

There are no conflicts of interest to be reported.

Funding Sources

There was no funding for this case report.

Author Contributions

Dr. Ellen Nollet is the resident at AZ Sint-Jan Brugge and main author of this case report. She has followed up the patient on each visit. Dr. Sara Van de Veire is the treating physician, following the patient as well. Dr. Nicolas Vandenbussche is the neurologist who was consulted in this case. Both Dr. Sara Van de Veire and Dr. Nicolas Vandenbussche have provided feedback during the writing of this case report.

Funding Statement

There was no funding for this case report.

Data Availability Statement

The data supporting the findings of this case report are not publicly available due to patient confidentiality. Individual patient data, including visual field examinations and OCT images, are stored in the hospital’s electronic medical record system and cannot be shared. The data and images are available from the head of the Department of Ophthalmology, author Dr. Ellen Nollet or coauthor Dr. Sara Van de Veire, upon reasonable request.