Findings on MR Imaging in Cat-Scratch Neuroretinitis

Abstract

Purpose:: To describe some features found on cranial Magnetic Resonance imaging (MRI) in a patient with neuroretinitis secondary to cat-scratch disease.

Methods:: We present a single case of neuroretinitis in an 11-year-old female who presented with a two day history of gradual deterioration of vision in her left eye. The visual loss was evaluated with a complete ophthalmologic evaluation including a dilated fundus examination which revealed swelling of the optic nerve head and a small macular hemorrhage, without a macular star configuration. History revealed that the patient had two pet cats, and on physical exam a healing scratch was found on her right wrist. MRI scan of the orbits was done to further evaluate the swollen optic nerve.

Results:: The T1 weighted, post-contrast, fat-suppressed MRI of the orbit showed focal revealed short-segment enhancement of the optic nerve localized to the optic nerve-globe junction. This pattern had been recently described as being highly specific for optic neuritis secondary to cat-scratch disease. Immunologic titers for Bartonella henselae were drawn, and the patient was started on antibiotics and steroids for presumed cat-scratch neuroretinitis. On subsequent follow up, the early formation of a macular star, the classic finding of neuroretinitis, was noted. Two days after initial presentation, IgG titers for Bartonella henselae, returned strongly positive. Over the next few weeks, the patient's vision continued to improve.

Conclusions:: This case demonstrates a clinical situation where MR imaging was important in guiding the diagnosis of neuroretinitis in the absence of the pathoneumonic macular star. Since MR imaging is often the first study obtained in the evaluation of optic neuropathy, we believe that it is important for ophthalmologists to be aware of these features in order to further guide the diagnostic evaluation and therapy.

Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • neuro-ophthalmology: optic nerve • bacterial disease