November 2021

An Under-Appreciated Headache

A 34-year-old female presented to her local hospital emergency department complaining of headaches and visual disturbance.  After being treated with analgesics she was discharged home.

When the headaches persisted she presented to her local optometrist requesting glasses to help alleviate the headaches.  The optometrist noted the changes in the optic nerve heads, as per the images below, and referred the patient for specialist management.

• What is the diagnosis?
• What further information would be useful?
• What other conditions can cause this appearance?

Content

Further History
Assessment
Diagnosis & Management
Approach

Further History

A 34-year old-female gives a history of gradually worsening headaches over the last 1 to 2 months.  She has recently noticed reduced vision, which she describes as patchy and worse in her left eye.  On further questioning, the patient gives a history of parietal meningioma resected 7 years ago.  She is obese with a BMI >40 but reported no other health problems.

Assessment

A full ophthalmic and general examination was performed.  Visual acuity was right 6/9 & left 6/45.  There was a subtle left RAPD.  Eye movements were full, and the rest of the neurological examination was normal.  Blood pressure, blood sugar and other vital signs were normal.  An OCT RNFL was attempted but could not segment the layers due to severe swelling (Figure 1).  A 30-2 visual field was performed, showing patchy depression of the right field and significant concentric field loss of the left (Figure 2).

Figure 1. OCT RNFL are not generally useful in initial diagnoses of disc swelling but can help with monitoring response to treatment.

Figure 2. 30-2 HFA visual fields showing patchy depression of the right field, and significant concentric field loss of the left eye.

Diagnosis & Management

The patient underwent a CT brain scan, which was normal.  She then underwent magnetic resonance imaging (MRI) of the brain and orbits and venogram.  This showed a congenital hypo-plastic transverse sinus, but interestingly, there was focal stenosis at the junction of the right transverse and sigmoid sinuses, at the location of the resection of the previous meningioma.  There were radiographic signs of raised intracranial pressure (ICP).

The patient was admitted to hospital in conjunction with the neurosurgical team.  A lumbar puncture showed extremely elevated intracranial pressure of 54cm H20 (normal <18cm H20).  The patient was diagnosed with intracranial hypertension due to venous sinus stenosis.

The patient had an urgent temporary lumbar drain inserted to control the ICP and intravenous acetazolamide was given.  The following day she underwent a left optic nerve sheath fenestration to relieve the local pressure around the nerve.  Over the following few days her vision was noted to improve.  She subsequently had an intravascular stent placed within the stenotic sigmoid sinus and was discharged from hospital a few days later.

Approach

Any swollen disc should be treated as potentially serious.  Similarly, headaches should be taken seriously as a number of benign and potentially dangerous conditions can present with headache.  It is useful to have a list of serious causes of headache and their common presenting features.  These are often known as the “red flags” of headache (Table 1).

“Knowing the red flags of headaches can help you sort the serious causes of headache from benign ones”
                                                                                                                                      — Dr Nick Toalster

Table 1. Red Flags of Headache

Any of the red flags should alert the clinician to the potential for more serious causes of headache. Swollen discs may also be due to other diseases, of which raised intracranial pressure is just one. Extremely elevated blood pressure, blood sugar as well as a number of infections, such as syphilis or tuberculosis as well as autoimmune diseases including multiple sclerosis can cause swollen discs which can be difficult to differentiate from those caused by raised intracranial pressure.

The urgency of treatment depends on the threat to vision. That is, how swollen are the discs and is there a reduction of optic nerve function. Patients with swollen discs should always have their nerve function assessed with a thorough pupil assessment, colour vision, visual acuity and computerised visual fields.

This case demonstrates a severely elevated intracranial pressure due to venous sinus stenosis. It highlights that assessing for significant factors in a patient’s history, such as a history of a previously treated brain tumour, as well as assessing nerve function and disc appearance are vitally important.