Eye (1991) 5,124-129

Double Vision as a Presenting Symptom in an Ophthalmic Casualty Department

R. J. MORRIS London

Summary All patients presenting with double vision as a principal symptom who presented to the Casualty Department of Moorfields Eye Hospital over a nine month period were prospectively investigated. Two hundred and seventy five patients were identified accounting for 1.4% of all casualties. Monocular diplopia was commoner than expected accounting for 69 cases (25.1 %) and was almost always a genuine symptom attributable to uniocular pathology, most commonly lenticular or corneal pathology. Two hundred and six patients (74.9%) had binocular diplopia and in most cases an aetiology was established. Cranial nerve palsies were the commonest cause of bio­ cular diplopia accounting for 81 cases. Other causes were classified as convergence or accommodation problems, decompensating phorias, traumatic, muscular, orbital lesions, supranuclear lesions, and other miscellaneous conditions. In eight cases of monocular and 23 cases of binocular diplopia no cause for the symptoms could be identified.

Diplopia is a common and distressing symp­ did not include patients with monocular diplo­ tom which may be the presenting feature of a pia. It has been stated in the literature that wide variety of ocular and neurological condi­ monocular diplopia is rare and that a cause tions. Many patients with double vision pres­ cannot usually be detected.7 Some authors ent directly to an ophthalmic accident and feel that psychogenic factors are the most emergency department and the ophthal­ common cause of this symptom.s However, mologist is the first clinician with the oppor­ there is no epidemiological information on tunity to establish the diagnosis and prevent prevalence of monocular diplopia in the liter­ unnecessary, time consuming and expensive ature to support these statements. investigations. The Casualty Department of Moorfields Previous studies have considered the prob­ Eye Hospital sees patients referred by their lem of diplopia, but only in selected patient general practitioners and opticians as well as populations. These have included a general walk in casualties (self-referrals), and there­ ophthalmic outpatient clinic, 1 orthoptic fore represents a relatively un selected patient departments2-4 and a paralytic squint c1inic.5 population. In order to investigate the inci­ However, these studies represent specific dence of diplopia as a presenting symptom, groups of patients and would exclude some of the proportion of patients with monoc(Jlar the common causes of diplopia. One study has and binocular diplopia and the aetiology of considered patients presenting with diplopia the symptom, a prospective study of consec­ to an ophthalmic emergency department,6 but utive patients with double vision as a principal

From: Moorfields Eye Hospital, City Road, London ECIV 2PD

Correspondence to: R. J. Morris, FRCS, FCOphth. Southampton Eye Hospital, Wilton Avenue, Southampton S09 4XW. DOUBLE VISION AS A PRESENTING SYMPTOM 125 complaint who presented to the Casualty symptoms were related to optical aberrations Department over a nine month period was from the edge of the lens and in two from the conducted. dialling hole. Seventeen patients (24.6%) had corneal pathology resulting in corneal scar­ Methods and Materials ring, epithelial irregularity or irregular astig­ All patients who presented with double vision matism. In addition three patients had as a principal complaint to the Casualty irregular corneal astigmatism induced by cen­ Department, Moorfields Eye Hospital, City tral lid chalazion. Road between April and November 1987 Four patients had monocular diplopia as a were included in the study. Patients referred r�sult of macular pathology. Two patients by other ophthalmologists for a second opin­ developed transient diplopia following ion were excluded from the study. The trauma but ocular examination was within majority of patients were examined by the normal limits. author at presentation, but when this was not In eight (11.6%) patients no cause for the possible, the notes were reviewed and dis­ complaint of monocular diplopia could be cussed with the examining ophthalmologist. established. Four of these patients were lost All patients with binocular diplopia were also to follow up and in four the symptoms sponta­ assessed by an orthoptist. When necessary neously resolved within six weeks. patients were referred to specialist ophthal­ mic and neuro-ophthalmic clinics for further Binocular Diplopia investigation. In some cases the patients were The causes of binocular diplopia are summar­ admitted for neurological investigation. All ised in Table II. Infranuclear cranial nerve patients without an aetiological diagnosis palsies were the commonest cause and were followed until their symptoms resolved. accounted for 81 cases (29.5% of all cases and 39.3% of binocular cases). No patient had Results more than one oculomotor nerve involved. Nineteen thousand six hundred and sixty four Cranial nerve palsies were most commonly patients attended the casualty department due to diabetes or microvascular disease (32 during the nine month period of the study. patients), although superior oblique palsies Two hundred and seventy five patients pre­ were most frequently due to longstanding sented with diplopia as a principal symptom congenital palsies (14 patients). Two patients accounting for 1.4% of all patients. Two hun­ with 3rd nerve palsies had orbital pseudo­ dred and six patients (74.0%) had binocular tumours, one also had involvement of the diplopia and 69 (25.1 % ) monocular diplopia. ophthalmic nerve, and the other had an iso­ lated palsy of the superior division of the 3rd Monocular Diplopia nerve. One patient developed an isolated The causes of monocular diplopia are sum­ inferior rectus palsy following ophthalmic marised in Table 1. Extra-ocular optical herpes zoster. Three patients had intracere­ causes accounted for seven patients' symp­ bral tumours, one a pituitary tumour invading toms. Spectacle induced diplopia resulted the cavernous sinus and two metastatic from the bifocal segment ledge in four tumours. Eight patients in this group were lost patients and refractive correction of myopia to follow up. in one. Contact lens induced monocular dip­ The next most common group of patients lopia occurred in two patients due to lens with binocular diplopia was that classified as decentration and lens spoilage. muscular. This included nine patients with Ocular abnormalities were the commonest squint, five with diplopia following cataract group of conditions causing monocular diplo­ surgery, two adults with Duane's syndrome, pia. Lens abnormalities accounted for 27 two with long standing tropias who had dis­ patients (39.1%) and included cortical, nucle­ ruption of suppression. ar and posterior subcapsular cataracts. Four Twenty seven patients had a history of patients in this group had decentred posterior trauma. Fifteen had a blow out fracture and chamber intraocular lens implants, in two the fivesustained blunt orbital trauma but a frac- 126 R. J. MORRIS

Table I. Causes of Monocular Diplopia

OPTICAL Extra-ocular Bifocal Spectacles 4 Contact lenses (soft) 2 Myopic spectacles 1 OClllar Lids Chalazion 3 Cornea Infections -Herpes simplex 2 -Adenovirus 1 -Thygesons 1 Trauma -Healing abrasions 3 -Trichiasis 1 -Toxic epitheliopathy 2 -Scarring 4 -Contact lens induced microcysts 1 Dystrophy -Keratoconus 2 Iris Pharmacological mydriasis 1 Holmes Adie pupil 1 Lens Lens opacities 23 Intraocular lens 4 Retinal Parafoveal neovascular membrane I Pigment epithelial detachment I Macular pucker 1 Central retinal vein occlusion I TRAUMA 1 NO CAUSE ESTABLISHED 8 ture could not be demonstrated radiologically sents the first study to investigate patients despite the presence of diplopia in vertical presenting to an ophthalmic emergency gaze positions. Two presented some days after department with monocular and binocular penetrating orbital trauma and one patient diplopia. It has been suggested that monocu­ developed post concussion syndrome follow­ lar diplopia is a rare complaint/ but this is not ing a closed head injury. Four patients pre­ borne out by these figures. It was commoner sented following non-strabismus surgery, than expected accounting for 25.1% of all three had symptoms-following successful ret­ patients presenting with diplopia and 0.35% inal detachment surgery and one following of all new casualties. Monocular diplopia repeated pterygium surgery which had arises when two images of the same object are resulted in a mechanical limitation of seen by one eye. Typically the secondary abduction of the involved eye. image is fainter than the primary image and Fifteen patients had diplopia associated may be continuous with it or separated from with supranuclear lesions. Six patients with it.9 In some cases triplopia or polyopia may be internuclear ophthalmoplegia were sub­ experienced by the patient. The second image sequently diagnosed as having multiple scler­ may be vertically or horizontally separated osis, four patients had transient diplopia from the primary image, and when due to len­ associated with brain stem ischaemia, three ticular causes the diplopia is typically had skew deviations related t6 cerebral vertical. uo ischaemia, one had migraine and one Wer­ There is no concensus in the literature as to nicke's encephalopathy. One patient with a the commonest cause of monocular diplopia. large pituitary tumour and bitemporal field Despite the claim that psychogenic factors are loss presented with hemifield slip. the most common cause of monocular diplo­ In 23 patients (11.1 %) no specificcause for pia8 in this study a genuine cause was found in 88.4% of cases. In the eight cases for which no the diplopia could be established. In 11 of cause could be identifiedthe symptoms spon­ these cases the symptoms had resolved within taneously resolved within six weeks in four six weeks and the remaining 12 patients were patients and the other four were lost to follow lost to follow up. up. Although several authors have stated that Discussion lenticular induced monocular diplopia is the This series of patients with diplopia repre- most common form,9.1l-13 Amos cautioned DOUBLE VISION AS A PRESENTING SYMPTOM 127

Table II. Causes of Binocular Dip/apia

SPECTACLES Bifocal intolerance 4 CONVERGENCE/ACCOMMODATION PROBLEMS Convergence insufficiency 6 Accommodative spasm 1 BREAKDOWN OF EXISTING OCULAR MUSCLE IMBALANCE Decompensating exophoria 3 Decompensating esophoria 10 TRAUMA Blow out fracture 15 Blunt trauma 5 Penetrating injury 2 Post surgical 4 Post concussion syndrome 1 MUSCULAR 'Squint' 9 Thyroid 11 Myasthenia gravis 7 Orbital myositis 1 ORBITAL Frontoethmoidal sinusitis 2 Orbital cellulitis 1 Orbital tumour 5 INFRA NUCLEAR LESIONS III Nerve palsy Diabetes mellitus 7 Vascular 3 Pituitary tumour 1 Orbital pseudotumour 2 Post traumatic 1 Inferior rectus weakness associated with herpes zoster ophthalmicus 1 Unknown 3 IV Nerve palsy Congcntial 14 Diabetes mellitus 1 Vascular 1 Herpes zoster 1 Trauma 6 Unknown 2 No follow up 1 VI Nerve palsy Diabetes mellitus 10 Vascular 10 Multiple sclerosis 4 Herpes zoster 2 Cerebral tumour 2 Benign intracranial hypertension 1 Unknown 6 No follow up 2 SUPRANUCLEAR LESIONS Internuclear ophthalmoplegia 6 Brain stem ischaemia 4 Skew deviation 2 'Migraine' 2 Wernicke's encephalopathy 1 HEMIFIELD SLIP 1 NO CAUSE ESTABLISHED 22

against this conclusion in the absence of epi­ diplopia to and low myopia or myopic astig­ demiological data,7 Physiological monocular matism14 have also been considered to be the 128 R. j. MORRIS most frequent cause of this symptom. How­ Binocular diplopia occurred more fre­ ever, in this study I identifiedonly one patient quently than monocular diplopia and with symptoms induced by low myopia and accounted for 74.9'10 of all of patients in this none with physiological monocular diplopia. study. The commonest cause was infranuclear Spectacle induced diplopia was most fre­ cranial nerve palsies (81 patients: 29.5% of all quently seen with bifocals. Monocular diplo­ causes and 39.3% of binocular causes). This pia in the presence of low refractive errors is figure is similar to other studies of patients thought to be the result of minor optical presenting with binocular diplopia.3.4 How­ irregularities, principally spherical aber­ ever, Trimble in a similar patient population ation.7.15 Coffeen and Guyton found that this reported a much higher incidence of cranial type of diplopia could be readily induced in, nerve palsies (73%)," as did Nolan in a study nine of 11 normal eyes examined.15 from a general ophthalmic outpatient clinic Lenticular abnormalities were the com­ (62.8%).1 monest cause of monocular diplopia in this The high incidence of traumatic cases has series and accounted for 27 (39.1%) cases. not been observed in other studies. Patients These are most commonly fluid clefts within presenting to general emergency departments the lens, early nuclear sclerosis, cortical with orbital trauma usually do so as a result of spokes or posterior subcapsular lens opaci­ the injury rather than diplopia. In contrast in ties. Physiological diplopia is also induced by this study many patients presented some days lenticular changes, probably due to refractive after their initial trauma when swelling had index changes within the lens.lO.11 In the four resolved and diplopia had become a promi­ cases related to decentred intraocular lenses nent symptom. the symptoms responded to pupillary con­ Five patients developed binocular diplopia striction with weak pilocarpine solution. It is following cataract surgery. In three of these interesting that although dislocated or sub­ there was a manifest strabismus prior to sur­ luxed lenses are a theoretical cause of mon­ gery and the patients developed symptoms ocular diplopia there have been no reports of following cataract extraction. Two patients this in the literature. Corneal disease was the had fusional loss after removal of longstand­ second commonest cause of monocular diplo­ ing traumatic cataracts, the mechanism of this pia and resulted from a wide variety of path­ has recently been discussed in the Iiterature.1H ological processes, but the common factor Thyroid eye disease and myasthenia gravis was either epithelial irregularity, irregular are important causes of diplopia and may co­ corneal astigmatism or corneal scarring. exist in some patients. Both conditions are Although some authors have described ret­ associated with other ocular and systemic fea­ inal conditions as a possible cause of monocu­ tures and can usually be diagnosed clinically. lar diplopia only three true cases have been In some cases a tensilon test, biochemical or reported in the literature.�·I(i.17 In this series radiological investigations may be needed to four patients had macular pathology account­ confirm the diagnosis. ing for their symptoms, but the double vision Previous studies of patients with diplopia they described was invariably associated with from orthoptic departments have shown a metamorphopsia. high incidence of convergence insufficiency The frequency of monocular diplopia in this (11 % and 33%), and decompensating hetero­ study emphasises the importance of thorough phorias (11% and 17%). These figures are clinical assessment in patients presenting with higher than in the present study and reflectthe diplopia. They should firstbe questioned as to type of patient seen in orthoptic departments whether or not the symptoms resolve when compared with that seen in casualty one eye is occluded. Having made the diag­ departments. nosis of monocular diplopia one must then Important but less common causes of diplo­ determine if the cause is opticaL If it is related pia included orbital disease and supranuclear to extraocular factors it will resolve when the lesions. Because of the potentially serious spectacles or contact lenses are removed. nature of these conditions such patients Optical factors of ocular origin will usually be require immediate investigation and eliminated with a pin-hole test.7 .12 treatment. DOUBLE VISION AS A PRESENTING SYMPTOM 129

In summary, the study has shown that diplo­ J Brown S, Atkins I, Doyle M, et al. Symptom pro­ pia is a common symptom which may be the ducing diplopia. Am Orthopt J 1983, 33: 105-10. "Yapp JMS: Diplopia as a presenting symptom. Br presenting feature of a wide range of ocular Orthopt J 1973, 30: 52-65. and neurological disorders. 5 Trimble RB: Diplopia as a presenting sign of neo­ Monocular diplopia was found to be much plasia. Trans Ophthalmol Soc UK 1980, 100: more common than previously reported and a 498-500. (; Trimble RB and Kelly V: Diplopia as a presenting cause was identifiablein the majority of cases. symptom: A prospective study. Proc IV Int Binocular diplopia occurred more frequently Orthop Congr, Berne 1979.91-4. than monocular diplopia and was most often J Amos JF: Diagnosis and management of monocular the result of an intranuclear cranial nerve diplopia. JAm Optom Assoc 1986, 53: 101-15. S Lepore FE and Yarian DL. Monocular diplopia of palsy. Patients with double vision usually retinal origin. J Clin Nellro-ophthalmolI986, 6: present to an ophthalmologist and in most 181-3. cases the diagnosis can be established by care­ 'I Records RE: Monocular diplopia. Surv Ophthalmol 1980,24: 303-6. ful clinical assessment of patients. Appro­ III Rubin ML. The woman who saw too much. Surv priate investigations can confirmthe diagnosis OphthalmoI1972: 16: 382-3. and establish the underlying aetiology avoid­ II Fincham EF: Monocular diplopia. Br J Ophthalmol ing unnecessary, time consuming and expen­ 1963,47: 705-12. 12 sive investigations. Lawton-Smith J: Monocular diplopia. (Editorial). J Clin Nellro-ophthalmoI1986, 6: 184-5. .1 1 D I should like to thank the nursing staff and registrars in Lee J and Elston J: iplopia. Br J Hasp Med 1985. the Casualty Department for their help during the 13-20. '" Scott AB: Diplopia in myopia. Surv Ophthalmol study, and the consultants who allowed me to report 1974, 19: 166-8. their patients. I should also like to thank Mr. A. 15 Coffeen P and Guyton DL: Monocular diplopia Moore, Mr. J. P. Lee and particularly Mr. J. Elston accompanying ordinary refractive errors. Am J who gave me valuable advice throughout the study. Ophthalmol 1988, 105: 451-9. Key words: Double vision, Monocular diplopia, Bin­ 1(; Evans J. Seeing double. Med Times Long Island ocular diplopia. Med J 1933,62: 132-4. 17 Negre M: Un case de vaste desinsertion avec infero­ References version de la retine. Diplopie monoculaire secon­ 1 Nolan J: Diplopia. Br J Ophthalmol 1968, 52: daire. Bull Soc d'Ophthal de Paris 1931, 42: 166-71. 196-201. 2 Boyd T, Ridgway C, Budd G: Childhood strabismus IX Pratt-Johnson JA, Tillson G: Intractable diplopia as a cause of persistent diplopia in adolescents and after vision restoration in unilateral cataract. Am adults. Can J Ophthalmol 1966, 1: 199-205. J Ophthalmol 1989, 107: 23-6.