Acute angle closure glaucoma following head and orbital trauma.

The case is reported of a 52-year-old woman who suffered a minor head injury and orbital trauma and returned 2 days later with a unilateral headache, vomiting and photophobia. This was initially thought to be secondary to her head injury but, once severe visual impairment and a dilated unreactive pupil developed, the true diagnosis became obvious. A diagnosis of acute angle closure glaucoma was made and she was treated with no complications. This case highlights acute angle closure glaucoma as an important diagnosis to consider in patients who present with unilateral headache and dilated pupil after head injury.

Pressor reactivity to norepinephrine and angiotensin in salt-sensitive hypertensive patients.

The mechanisms responsible for increased blood pressure in response to a high dietary sodium intake in salt-sensitive patients with essential hypertension are only partially understood. The possibility that increased reactivity to pressor hormones might contribute to hypertension in these patients has not been adequately investigated. We studied 11 salt-sensitive and 15 salt-resistant patients with essential hypertension while they were ingesting a diet with 20 meq/day sodium for 9 days or one with 200 meq/day sodium for 14 days. During the last 4 days of each dietary regimen, they received 30 mg/day of slow-release nifedipine. Blood pressure response to increasing doses of norepinephrine and angiotensin II (Ang II) was studied at the end of each of four phases of the study. Salt-sensitive patients exhibited a greater blood pressure response to norepinephrine than salt-resistant patients, irrespective of the dietary sodium intake and whether we took into account the dose infused or the actual plasma levels of norepinephrine achieved during the infusion. The blood pressure response to Ang II, on the other hand, was greater in salt-sensitive than salt-resistant patients during low but not during high sodium intake. The blood levels of norepinephrine achieved during the infusion of this hormone were lower in salt-sensitive than in salt-resistant patients. These studies indicate that an increased reactivity to the pressor action of norepinephrine might contribute to the maintenance of hypertension in salt-sensitive patients. The increased reactivity appears to be specific for norepinephrine. In fact, we observed increased reactivity to Ang II during low but not during high sodium intake.(ABSTRACT TRUNCATED AT 250 WORDS)

Optic disc drusen and episodic visual loss.

A case is reported in which recurrent episodes of visual loss occurred over a period of 26 years in a patient with bilateral optic disc drusen. Visual field loss was associated with episodes of ischaemic optic neuropathy. The possible mechanism is discussed.

Intraocular pressure changes after peribulbar injections with and without ocular compression.

AIM: Two prospective studies were carried out in order to investigate (1) the rise in intraocular pressure (IOP) following peribulbar anaesthesia with a fixed volume of anaesthetic agent administered by a single surgeon, and (2) the efficacy of ocular compression with the Honan balloon for lowering IOP. Glaucomatous eyes were excluded from both studies. METHODS: In study group 1, 36 eyes of 36 patients undergoing cataract and/or implant surgery each received peribulbar injections consisting of 5 ml of anaesthetic from an inferotemporal site through the conjunctiva and a further 5 ml from a medial injection through the caruncle. IOP values were measured immediately before and after the injections and then after a variable period of external ocular compression. In study group 2, 20 eyes of 20 patients undergoing cataract surgery received peribulbar injections of local anaesthetic as above. IOP values were measured immediately before and after the injections and after 20 minutes without ocular compression. After a further 20 minute period with ocular compression the IOP was again measured. RESULTS: In study group 1, the mean immediate rise in IOP induced by the injections was 11.44 (95% confidence interval 8.97-13.90) mm Hg. The mean change in IOP after ocular compression was an overall fall of 2.42 (0.49-4.34) mm Hg from the pre-injection value. In study group 2, the mean injection induced rise in IOP was 9.45 (6.90-12.00) mm Hg. The mean fall in IOP during the first 20 minutes without ocular compression was 2.85 (1.20-4.50) mm Hg. During the second 20 minutes with ocular compression the mean fall in intraocular pressure was 11.05 (8.14-14.96) mm Hg. CONCLUSIONS: There is a large and individually variable rise in IOP following peribulbar anaesthesia. Ocular compression with the Honan balloon is effective in reversing this rise even when the initial rise is large.

Antibodies to herpes simplex virus type I in intraocular fluids of patients with acute retinal necrosis.

The intraocular fluids and sera from three patients with acute retinal necrosis (ARN) and from 120 age-matched controls were tested for the presence of antibodies to herpes simplex virus type I (HSV-I). Antibodies to HSV-I were detected in both intraocular fluids and sera of two cases, and in intraocular fluids alone in one case of ARN. Among 120 control patients undergoing routine intraocular surgery antibodies to HSV-I were detected in the sera of 85 (79.2%) but in the intraocular fluids of only two (1.7%). The presence of antibody within the eye may indicate local antibody production, antibody sequestration within the eye, or damage to the blood ocular barrier.

Clinical comparison of the Keeler Pulsair 3000 with Goldmann applanation tonometry.

AIM: To confirm the accuracy of the Pulsair 3000 before introducing the instrument into clinical practice. METHOD: A masked study by two experienced tonometrists comparing the mean of the Goldmann intraocular pressure (IOP) readings against the Pulsair 3000 reading (average of four puffs). Results of 150 eyes were compared with an IOP range of 10 mm Hg-44 mm Hg. RESULTS: Correlation between the two Goldmann tonometry results was 0.9830 with a standard deviation of 1.1085 mm Hg. Correlation between the mean of the two Goldmann readings against the Pulsair 3000 reading was 0.982 with a standard deviation of 1.1179 mm Hg. Bland-Altman analysis confirms a satisfactory outcome. CONCLUSION: The Pulsair 3000 provides an accurate and objective method of measuring IOP with many advantages over traditional Goldmann tonometry.

Intracerebral metastases from ocular melanoma.

A blind painful eye may harbour an unsuspected malignant melanoma. We report a case of ocular melanoma that presented with confusion owing to direct extension via the optic nerve into the anterior cranial fossa.

Optic nerve sheath meningioma: diagnostic features and therapeutic alternatives.

Twenty-two cases of optic nerve sheath meningioma were reviewed. The clinical features included slowly progressive visual loss in every case. Orbital signs of limited ocular movements and mild proptosis were present in only a third of cases; gaze-evoked amaurosis occurred in 3 cases. The disc was abnormal in every case, usually swollen if vision was 6/12 or better, atrophic if the vision worse than 6/12. Optociliary shunt vessels occurred in 5 patients and were of diagnostic significance. The diagnosis was made by a high-resolution CT scan of the orbits showing tubular expansion of the optic nerve sheath. Calcification of the optic nerve was present in 12 cases. Tubular expansion of the optic nerve sheath may occur in raised intracranial pressure, optic nerve glioma, granuloma, lymphoma or metastatic disease. In the absence of calcification these alternative diagnoses must be considered. Surgery, undertaken for the intracranial component of the tumour, did not halt progressive visual loss.

Assessment of visual function in idiopathic intracranial hypertension: a prospective study.

The visual function of 35 patients with a diagnosis of idiopathic intracranial hypertension was assessed prospectively over a 3 year period. In assessing the visual function of cases of idiopathic intracranial hypertension a number of tests were employed including visual field assessment with Humphrey and Goldmann perimeters and documentation of visual acuity and contrast sensitivity. Loss of visual function is the only serious complication and may occur early or late in the course of the condition. An appropriate and sensitive clinical assessment regime is therefore of importance in the outpatient situation. Visual field assessment was documented as the most sensitive to detection of visual loss, with statistically greater sensitivity in comparison with visual acuity and contrast sensitivity testing. Detection of asymptomatic visual loss indicates the necessity for visual monitoring to ensure detection of insidious visual loss. The types of visual field defects noted in this study were typical of anterior optic nerve pathology of raised intracranial pressure and commonly included arcuate defects, nasal steps and global constriction. Visual loss was noted at presentation and during follow-up in up to 87% of patients using Goldmann perimetry and up to 82% of patients using Humphrey perimetry. The visual status improved significantly throughout the follow-up period and the final visual outcome was excellent or good in 83% of patients.

Ocular disease in immunosuppressed patients.

New therapies and diseases causing immunosuppression have provoked new and devastating ocular diseases. The possible reasons for the vulnerability of the retina to opportunistic infections are discussed. The clinical patterns of disease caused by common opportunistic agents are described, and current treatment available is reviewed.

Convergence spasm.

Convergence spasm, when it is part of the near-response, is accompanied by accommodation and miosis. The differential diagnosis of bilateral sixth nerve palsy, divergence insufficiency, bilateral gaze palsy may be distinguished by clinical examination. In a review of 12 cases, 8 of whom were re-examined after a mean interval of 8.3 years, no organic disease became manifest. We suggest that extensive neurological investigation is not necessary in this group of patients. Treatment with cycloplegia and glasses gave symptomatic relief in 5 cases.

Silicone tube and gutter in advanced glaucoma.

We performed a new drainage operation in 20 cases of advanced glaucoma. A silicone tube was inserted into the anterior chamber and its outer end buried under an encircling gutter. After a mean follow up of 10 months, in 13 cases (65 per cent) the eye was comfortable, the intraocular pressure less than 25 mm Hg, and the tube was in a satisfactory anatomical position. The authors recommend this procedure rather than destructive operations in eyes with advanced uncontrolled glaucoma.