Correspondence
Fulminant idiopathic intracranial hypertension managed with oral acetazolamide
Idiopathic intracranial hypertension (IIH), also known as pseudotumour cerebri, is a syndrome of increased intracranial hypertension of unknown cause found predominantly in women of childbearing age and associated with an increased body mass index or a history of recent weight gain.1 The modified Dandy criteria for diagnosing IIH include (i) an imaging study confirming the absence of radiographic hydrocephalus or mass lesion, (ii) elevated cerebrospinal fluid (CSF) opening pressure (OP) upon lumbar puncture (LP) with normal CSF contents, and (iii) an intact neurologic examination with the exception of visual disturbances, sixth cranial nerve palsy, and papilledema.Bilateral posterior ischemic optic neuropathy associated with the use of Sildenafil for pulmonary hypertension
Sildenafil citrate is a selective phosphodiesterase (PDE)-5 inhibitor (PDE5i) and a partial PDE-6 inhibitor that enhances nitric oxide and cyclic guanosine monophosphate (cGMP), leading to smooth muscle relaxation. It has been used as an erectile dysfunction agent in men but also improves pulmonary hemodynamics and exercise capacity in symptomatic pulmonary arterial hypertension.1 PDE5i has been reported to cause transient changes in vision, colour perception (e.g., blue or blue-green tinges), brightness perception, and electroretinography.Neuro-ophthalmic presentations of clival plasmacytoma
Neurologically isolated cranial mononeuropathy (e.g., sixth nerve palsy) leading to diplopia is a common presentation to ophthalmologists. Although rare, clival lesions can cause isolated unilateral or bilateral abducens palsies with or without papilledema. Intracranial plasmacytomas (ICPC) are rare tumours that constitute less than 1% of intracranial neoplasms. They may present as a solitary plasmacytoma or may be part of a systemic malignant plasmacytosis, as in multiple myeloma (MM).Bilateral optic atrophy in endemic typhus
Murine typhus is an infectious disease caused by Rickettsia typhus. The disease is transmitted to humans by rat fleas through direct inoculation.1 Southeast Texas has one of the highest incidence rates of endemic typhus in the United States.2–5 Ophthalmic manifestations of murine typhus include vitritis, retinal lesions, and retinal vascular leakage.6–10 Optic neuropathy in the setting of murine typhus has been rarely described and only in the setting of disc edema or optic neuritis.8–11 We present a rare case of bilateral optic atrophy as the presenting ophthalmic sign of R.
