Transient unilateral ophthalmoplegia without papilledema in a child with intracranial hypertension

Abstract

Intracranial hypertension is usually presented with papilledema and headache. Complete ophthalmoplegia without papilledema is a very rare finding of intracranial hypertension in children.

A 5-year-old male patient with unilateral ophthalmoplegia due to increased intracranial pressure is presented. The fundoscopic examination and the magnetic resonance imaging of the brain were normal. He underwent lumboperitoneal shunt insertion for intracranial hypertension and the ophthalmoplegia was resolved one month later.

Complete ophthalmoplegia without papilledema may occur following intracranial hypertension. Prompt and accurate diagnosis should be done and appropriate treatment to reduce the pressure should be performed to save the life of the children.

1. Introduction

Complete ophthalmoplegia, the combination of ptosis with loss of all extraocular movements, is rarely a consequence of intracranial hypertension. It can be produced acutely by conditions involving the neuromuscular junction (such as myasthenia gravis or botulism), ocular motor nerves (such as Miller–Fisher or Guillain–Barre’ syndromes), or brain stem (such as anticonvulsant drug intoxications or Wernicke syndrome) (Thurtell and Halmagyi, 2008). Although intracranial hypertension has been identified as a cause in a minority of patients, a mechanism for the ophthalmoplegia has not been postulated. Papilledema is clinically defined as optic disc swelling resulting only from increased intracranial pressure (ICP). Cerebrospinal fluid pressure (CSF) equal to or greater than 25 cm H₂O taken in a person lying in the lateral recumbent position is considered abnormally elevated and meaning that the patient had intracranial hypertension (Chan, 2007). Intracranial hypertension may cause complete ophthalmoplegia, but it is usually associated with papilledema (Arsava et al., 2004; Bruce et al., 2006). Sparing of the optic disc swelling in cases of intracranial hypertension is very rare.

We reported a child with transient complete ophthalmoplegia due to increased ICP and papilledema was not observed. Possible pathophysiological mechanisms were discussed.

2. Case report

A 5-year old male patient, born prematurely at the 27th gestational week, underwent ventriculoperitoneal shunt insertion for hydrocephalus. When he was 4-year old, he underwent shunt revision for the obstruction of the ventricular catheter. His complaint, headache, was resolved after the revision at that time. The patient was admitted to our department with the history of mild headache lasting for 5 months and severe headache associated with nausea-vomiting in the last 2 days. The patient was normotensive and the blood tests were in normal ranges. On his neuro-ophthalmological examination, the right eye showed complete lid ptosis with no levator function. The pupil was dilated in the right eye. Both direct and consensual light reflex were absent in the right eye and were intact in the left eye. While ocular movements were absent in all directions of gaze in the right eye (Fig. 1), there was only limitation of abduction in the left eye. Biomicroscopic and fundoscopic examinations were normal in both eyes (Fig. 2). The visual acuity in right eye was 3/10 Snellen lines and 8/10 Snellen lines on the left eye. The cranial nerve examination of right eye showed third, fourth and sixth nerve palsies while left eye showed only sixth nerve palsy. The computed tomography (CT) and magnetic resonance imaging (MRI) of the brain were not revealed any mass lesion or shunt malfunction (Fig. 3). The lumbar punction (LP) was performed and the opening pressure was 70 cm H₂O. The pressure was reduced to 15 cm H₂O and the symptoms, headache and nausea-vomiting were resolved for a short time. The LP was repeated for 3 times and the patient was benefited. The biochemical and microbiological analysis of the CSF were in normal ranges, including the viral antibodies. The possible diagnosis was intracranial hypertension. The lumboperitoneal shunt (LPS) was inserted to reduce the intracranial pressure. The symptoms of intracranial hypertension were resolved after the surgery, except ophthalmoplegia, and the patient was discharged. At the first month after the surgery, ophthalmoplegia was completely improved with minimal anisocoria. At the end of first year after the LPS insertion, the patient had no symptoms of intracranial hypertension, there was not anisocoria, and the ocular movements were normal.

Figure 1.

The pupil was dilated and fixed in the right eye. Both direct and consensual light reflex were absent in the right eye and were intact in the left eye. While ocular movements were absent in all directions of gaze in the right eye.

Figure 2.

Biomicroscopic and fundoscopic examinations were normal in both eyes.

Figure 3.

The axial (A), sagittal (B) and coronal (C) MRI scans of the patient not showed any mass lesion or hydrocephalus.

3. Discussion

Transient complete ophthalmoplegia without papilledema in a child with intracranial hypertension was reported. Optic nerve sheath defect may be the possible cause of optic disc sparing. Increased CSF pressure may compress the spinal venous system and this may transmit the pressure to the cavernous sinus. Oculomotor, trochlear and abducens nerves may be affected from the increased pressure in the cavernous sinus and complete ophthalmoplegia occured. The lumboperitoneal shunt reduced the spinal CSF pressure and the ophthalmoplegia was gradually resolved.

Papilledema is clinically defined as optic disc swelling resulting only from increased ICP, as opposed to the optic disc swelling from other etiologies, such as ischemia or inflammation (Killer et al., 2009). CSF pressure equal to or greater than 25 cm H₂O taken in a person lying in the lateral recumbent position is considered abnormally elevated. Normal CSF pressure is usually in the range of 10 cm H₂O to 25 cm H₂O (Chan, 2007).

Intracranial hypertension without papilledema is rarely reported but may well be a clinically important syndrome (Marcelis and Silberstein, 1991; Wraige et al., 2002). Our patient, except for the absence of papilledema, fit the following accepted criteria for intracranial pressure:

• 1.Headache.
• 2.History: Previous hydrocephalus and shunt insertion.
• 3.Examinations: Physical and neurologic examination results are within normal limits, except for ophthalmoplegia and anisocoria. No papilledema is present, but there is complete ophthalmoplegia on the right eye.
• 4.Lumbar puncture: LP demonstrates increased CSF pressure with a normal composition.
• 5.Radiological examination: The CT or MRI scans show no evidence of an intracranial mass or hydrocephalus.

It is believed that intracranial hypertension should be considered even in the absence of papilledema (Tibussek et al., 2010). Many mechanisms have been postulated for the absence of papilledema in patients with increased intracranial pressure as follows (Marcelis and Silberstein, 1991):

• (1)Bilateral congenital optic nerve sheath defects.
• (2)Bilateral acquired optic nerve sheath defects.
• (3)“Chronic pseudotumor cerebri” with resolution of papilledema.
• (4)Intermittent elevation of intracranial pressure below the threshold to produce papilledema. Bilateral congenital optic nerve sheath anomalies may explain the absence of papilledema despite elevation of CSF pressure. The CT and MRI scans are normal; however, sensitivity and specificity of imaging in this setting is undetermined. Autopsy or surgical documentation of optic nerve sheath defects may be helpful in future investigations (Marcelis and Silberstein, 1991).

Intermittent elevation of intracranial pressure below the threshold needed to produce papilledema is another possibility. But our patient had a persistent elevation of CSF pressure greater than 25 cm H₂O with serial LP. The threshold pressure level needed to develop papilledema is unknown.

The mechanism of headache in increased intracranial pressure is unknown. Traction on intracerebral pain-sensitive vessels, transient herniation of hippocampal gyri, and traction on cranial/cervical nerves with increased CSF pressure are postulated mechanisms of headache development. Alternately, changes in CSF pressure or flow may stimulate or inhibit central nervous system receptors (i.e., adenosine receptors) that produce headache (Marcelis and Silberstein, 1991).

Ophthalmoplegia can also be seen in intracranial hypertension and usually resolves with lowering of intracranial pressure (Arsava et al., 2004; Bruce et al., 2006; De Benedetti et al., 2008; Moosa et al., 2004). Although sixth nerve palsy is common with this condition, gaze pareses, skew deviation, and third or fourth nerve palsies are exceedingly rare and usually point out the secondary causes of increased ICP such as meningeal processes or venous sinus thrombosis (Moosa et al., 2004). The rapid resolution of the eye movement abnormalities and the signs of increased ICP after LPS insertion suggested a direct relationship to intracranial hypertension (Arsava et al., 2004; Bruce et al., 2006; Gard, 2009). In our case, complete ophthalmoplegia is an unusual clinical sign for intracranial hypertension. Increased spinal CSF pressure may be transmitted to the cavernous sinus by spinal venous network and may cause third, fourth and sixth nerve palsies (Parkinson, 1998). We suggested that the gradually reduction of the spinal CSF pressure by LPS decreased pressure in the cavernous sinus and improved the ophthalmoplegia.

In conclusion, ophthalmoplegia without papilledema should be kept in mind in patients with intracranial hypertension. The CSF diversion procedures should be applied if the patients benefit from the LP. Prompt diagnosis and treatment are crucial, especially in children.