Gordon N Dutton

The characteristics of midfacial fractures and the association with ocular injury: a prospective study

Ocular injuries commonly occur in patients with facial fractures. This prospective study was set up to determine the incidence of ocular injuries, as assessed by an ophthalmologist, in patients who had sustained midfacial fractures. Over a 2-year period, a study of 363 patients who had sustained midfacial trauma sufficient to lead to a facial bone fracture (438 fractures) was undertaken and patients received a comprehensive examination by an ophthalmologist and an orthoptist within 1 week of injury. The characteristics of the eye injuries sustained were related to the aetiology of the fracture, the type of fracture, and the sex and age of each patient. Ninety percent of patients sustained ocular injuries of various severities. Sixty three percent of patients sustained only minor or transient ocular injuries, 16% suffered moderately severe ocular injury and 12% experienced severe eye injuries. Road traffic accident was associated with the highest incidence of severe ocular disorder (9/45 = 20%) whilst assaults had the second highest incidence at 11% (20/181). One third of all patients with comminuted malar fracture suffered a severe ocular disorder (9/27) whilst blow-out fracture came second at 16.7% (6/36). Fifty six patients (15.4%) had a decrease in their visual acuity and 9 patients (2.5%) had significant traumatic optic neuropathy. Decrease in visual acuity was the main clinical finding accompanying the majority of significant eye injuries. When ocular injuries were related to aetiology, it was apparent that road traffic accidents and assaults associated with alcohol abuse showed the highest incidence of major ocular dysfunction. It is suggested that all patients sustaining midfacial fracture associated with a significant decrease in visual acuity either pre- or postoperatively should have an early ophthalmological review.

Treatment of retrobulbar haemorrhage in accident and emergency departments.

Retrobulbar haemorrhage is a rare complication of orbital injury or surgery. After injury the first clinicians to see these patients are often the staff of accident and emergency departments. This survey was instigated after several patients had been referred to our care irreversibly blind. A multiple choice questionnaire was devised and sent to 90 doctors working in accident and emergency departments in Scotland. A total of 57 (63%) were returned of which 55 were complete enough to analyse. The range of respondents was: consultants (n = 6), associate specialists (n = 3), senior registrars (n = 3), registrars (n = 4), senior house officer (n = 35), and clinical assistants (n = 4). Twenty nine of the 35 senior house officers (83%) were unable to diagnose and treat retrobulbar haemorrhage. Most consultants, senior registrars, registrars and associate specialists were significantly better in the diagnosis and treatment of this condition (P = 0.001). We conclude that there is an unacceptably high incidence of blindness as a result of inappropriate diagnosis and treatment of retrobulbar haemorrhage. We have therefore designed a protocol for accident departments which should help reduce the incidence of blindness.

Diplopia following midfacial fractures

Over a period of 2 years, 363 patients who had sustained a total of 438 midfacial fractures due to blunt trauma received a full ophthalmological examination within 1 week of injury. Of these, 72 patients (19.8%) developed diplopia. Diplopia was most common following road traffic accidents (31%) and least common with simple falls (10%). Blow-out fractures of the orbit led to double vision in 58% of cases. Eighty two percent of patients recovered from diplopia within 6 months of injury; only 1 patient required squint surgery for double vision. The principal risk factors for diplopia comprise road traffic accidents, blow-out fractures and comminuted malar fractures. Early surgical reconstruction of midfacial fractures with conservative management of concomitant motility disorders has, in our series, resulted in very few patients having diplopia in the long term.

Color Doppler Velocunetry of the Optic Nerve Head in Arterial Occlusion

BACKGROUND Color Doppler velocimetry allows simultaneous imaging by B-scan and Doppler ultrasound. This facilitates estimation of blood velocity in the orbital vessels. A pulse arterial waveform providing blood velocity measurements can be obtained from the optic nerve head. The vascular pattern in this region consists of multiple peripapillary blood vessels and a central artery. The exact contribution of the arteries in this area to velocimetry readings was undetermined. METHODS In this study, the arterial pulses at the optic nerve head of seven patients with central retinal artery occlusion (CRAO) and seven with anterior ischemic optic neuropathy (AION) were examined by color Doppler velocimetry. RESULTS No velocimetric measurements were obtainable at the optic nerve head in three of four patients with acute CRAO (examined within 24 hours of onset) despite color recordings obtainable in the peripapillary region. In contrast, all patients with AION showed characteristic arterial pulse waveforms from the artery that was situated centrally in the optic nerve. No peripapillary color indices were detectable in three of the four patients with ischemic optic neuropathy who were examined within 24 hours of onset of their symptoms. Follow-up investigation showed that there was reperfusion of both arterial circulations within 1 week. CONCLUSION The results demonstrate that color Doppler ultrasound of the optic nerve head provides velocimetric measurements of blood flow in the central retinal artery. Although some investigators using different apparatuses have produced velocimetry measurements from the posterior ciliary arteries, in this study reliable measurements were not obtainable form color indices in the peripapillary area.

Colour Doppler velocimetry of the arterial vasculature of the optic nerve head and orbit

Blood flow in the orbital vasculature can be investigated by colour Doppler velocimetry which allows simultaneous imaging of B-scan and Doppler ultrasound. In this paper we review the results of our recent studies on the arterial vasculature of the orbit and optic nerve head. A control study is described in which reliable measurements were obtained from the ophthalmic artery at the orbital apex, the medial orbit, and the complex of the central retinal artery and posterior ciliary arteries. Patients with occlusion of the central retinal artery and posterior ciliary arteries were examined. The results indicate that readings at the optic nerve head primarily represent blood flow in the central retinal artery. A study of the effects of posture on velocimetry demonstrated no change in the measurements obtained. Finally, topical timolol 0.5% was found to reduce the resistive indices of flow in the central retinal artery.

Colour Doppler ultrasound in the management of a case of cranial arteritis.

Colour Doppler ultrasound allows simultaneous B scan and Doppler imaging and can be employed to determine the velocity of blood flow in the vasculature of the eye and orbit. We describe a case of cranial arteritis (giant cell arteritis) in which serial velocimetry recordings were obtained. At one stage in the disease process no blood flow was detectable in the orbit despite previously reliable recordings. This coincided with a deterioration of the clinical state of the patient as signified by recurrent anterior ischaemic optic neuropathy despite controlled symptomatology and erythrocyte sedimentation rate by prednisolone therapy. Subsequent increase in the immunosuppressive therapy was accompanied by a return of blood flow in the orbit. Colour Doppler ultrasound may prove to be a useful examination technique in the diagnosis and management of cranial arteritis.

Midfacial fractures and the eye: the development of a system for detecting patients at risk of eye injury

Maxillofacial trauma is often complicated by injury to the eye. Such injuries may be difficult to detect and may therefore be missed. Detailed ophthalmic examinations were carried out prospectively on 363 patients who had sustained midfacial fractures. Fifty four parameters comprising maxillofacial, radiological and ophthalmic data were recorded and coded for each patient. All encoded data were divided into predictors (the data potentially available to the maxillofacial surgeon) and outcome (the data potentially available to the ophthalmologist). Statistical methods of regression, and the analysis of contingency tables, led to the identification of the principal predictors indicative of underlying ophthalmic injury and thence to a scoring system which predicts the severity of such injuries. Impaired visual acuity is the principal predictor and when employed alone gives a sensitivity value of 80%. Pure blow-out fracture or comminuted facial fracture, double vision and amnesia emerged as additional factors which yielded an efficient scoring system with a sensitivity of 89% and specificity of 90% for the population upon which it was based. A score sheet is provided in the paper. These predictors can be remembered from the acronym Blow-out fracture, Acuity, Diplopia, Amnesia, Comminuted Trauma. As many such injuries result from a BAD ACT, it is easily remembered. This scoring system requires to be tested upon a new population of individuals in order to determine its efficacy.

The Pulfrich phenomenon and its alleviation with a neutral density filter.

A case is described in which a presumed vascular accident resulted in long-standing visual difficulties in both reading and the analysis of vectors of moving objects. Clinical examination revealed minimal right optic atrophy with a relative superior altitudinal visual field defect associated with a positive Pulfrich effect. A partial head turn to the right in association with paresis of saccades and pursuit eye movements to the right was also evident. Spectacles for distance which incorporated a neutral density filter before the left eye were prescribed. These practically eliminated the Pulfrich effect and alleviated the problems of vector analysis. A near correction was provided which incorporated prisms with bases to the right. This eliminated the reading difficulties. The visual problems experienced by patients suffering from a positive Pulfrich effect are described and discussed.

Ophthalmic consequences of mid-facial trauma

Fractures of the mid-face are commonly accompanied by injury to the visual system. Three hundred and sixty three patients who had sustained mid-facial fractures were assessed prospectively for evidence of such injury. The data have been used to devise a scoring system for the maxillofacial surgeon in order to help identify those patients at risk of eye injury. The scoring system has been evaluated on a further cohort of 100 patients with a similar spectrum of injury and the sensitivity and specificity of the system have been determined. The results of these studies have been reported in the maxillofacial literature. This paper reviews the data and results obtained. In summary, impaired visual acuity with a comminuted or out blow fracture, a motility abnormality, or facial fracture combined with head injury, sufficient to cause both retrograde and post-traumatic amnesia, emerged as major risk factors which are indicative of an adverse ophthalmic outcome deemed to warrant referral. The scoring system which was developed from this data was found to have a sensitivity of 94.4% and a specificity of 89% for the detection of patients thought to merit ophthalmic assessment. Failure to assess central visual function as objectively as practicable in patients who have sustained mid-facial fractures may lead to potentially treatable ophthalmic pathology not being identified.

Midfacial fractures and the eye: the development of a system for detecting patients at risk of eye injury-a prospective evaluation

Midfacial trauma is often complicated by ocular disorder. A scoring system has been devised to help the maxillofacial surgeon identify patients who warrant referral to an ophthalmologist. A prospective pilot study was carried out on 100 patients with midfacial fractures to evaluate the effectiveness of this system in clinical practice. The sensitivity value was 94.4% and the specificity value was 89%. Only 1 patient, who clinically warranted referral to an ophthalmologist, was missed by the system whilst 9 others were incorrectly classified as warranting referral. The results of this evaluation demonstrate the competence of the system.