Most of our knowledge conceming the role of the blood-retinal barrier in human retinal disease has been derived through the clinical use of fluorescein angiography. A direct correlation between fluorescein 'leakage' and breakdown of the bloodretinal barrier has been established by the work of Cunha-Vaz and Maurice (I967) who demonstrated an active transport of fluorescein at the bloodretinal barrier level.Fluorescein angiography, is not quantitative, and shows low sensitivity and reproducibility in assessing fluorescein permeability. A clinical quantitative method for the study of the blood-retinal barrier has been developed and is reported in this paper.An alteration of the blood-retinal barrier has been proposed (Ashton, I965; Cunha-Vaz, 1966, 1972 Norton and Gutman, I967) as one of the earliest retinal changes in diabetes. The development of the technique of vitreous fluorophotometry prompted us to examine a series of diabetic patients, particularly those who failed to show any retinal lesions with other methods of fundus examination. Material and methods VITREOUS FLUOROPHOTOMETRYTo measure the fluorescein concentration in the vitreous, a model 360 Haag-Streit slit lamp was modified by adapting a new source of illumination, appropriate filters, a photometric detection system similar to that described by Waltman and Kaufman (1970) for the examination of the anterior chamber, and a device for electrical registration of the movement of the instrument. Slit lampThe incandescent bulb normally present in the slit lamp was replaced by a fibreoptic system connected with a 150 W unit and with ventilation.* A holder containing MicroscopeThe photometric detection systemt consisted of a modified eyepiece containing a fibreoptic probe, so designed that it could be superimposed on any area of the image of the optical cross-section, connected to a photomultiplier tube (EMI 9502), an autoranging photometer (2900), and either a recorder (500 XY) or an oscilloscope with storage (Tektronix 5103N5AI8N5B ioN) (Fig. i). The sensor tip of the probe, which was 0I5 mm in diameter, focused simultaneously with the optical section, thus allowing the fluorescein concentration to be measured in all parts of the eye visible in the ocular of the slit lamp. The overall sensitivity of the instrument could be varied by adjusting the voltage across the photomultiplier tube while a standard solution of fluorescein was observed. The instrument has been shown to be stable after an initial warm-up period of about 30 minutes.As the instrument scanned, it registered electrically by a system similar to that described by Kaiser and Maurice (I964). A linear carbon potentiometer was clamped to the slit-lamp table and a sliding contact was moved by a rod held against the base of the instrument. The output from the potentiometer was brought to the X plates of the recorder. A manual switch was placed in line with the Y terminal of the recorder to mark the positions of the retinal and lens surfaces. All the measurements were made after application of a Wor...

Diabetic macular oedema (DMO) is the leading cause of vision loss in the working-age population. Blood-retinal barrier (BRB) dysfunction in diabetic retinopathy (DR), mainly at the level of the retinal vessels, has long been related with leakage and fluid accumulation, leading to macular oedema. However, the nourishment of the macula is provided by the choroid and a diabetic choroidopathy has been described. Therefore, there has been a growing interest in studying the role of the choroid in the pathophysiology of DR and DMO, mainly by optical coherence tomography (OCT). Nevertheless, there are conflicting results in the different studies. We summarize the results from the available studies, describe the limitations and confounding factors and discuss future procedures to avoid bias.

Purpose: To report an uncommon case of a 29-year-old Caucasian male diagnosed with unilateral choroidal neovascularization (CNV) secondary to punctate inner choroidopathy leading to visual impairment. Methods: This is a retrospective and descriptive case report based on data from clinical records, patient observation and analysis of ancillary diagnostic tests. Results: A 29-year-old Caucasian male presented to our emergency department with complaints of decreased central vision in his left eye (LE), detected a few hours before. Best-corrected visual acuity (BCVA) in the LE was counting fingers at 50 cm and BCVA in the right eye was 20/20. Fundoscopy of the LE evidenced multiple round and yellowish lesions in the macula and nasal to the optic nerve, without intraocular inflammation signs. Optical coherence tomography showed increased retinal thickness with detachment of the neuroepithelium and a slight retinal pigment epithelium detachment. Fluorescein angiography revealed hyperfluorescent lesions with blurred borders in the macula. An intravitreal injection of bevacizumab (1.25 mg/0.05 ml) was administered in the LE, which resulted in anatomic and visual improvement. Conclusion: We present a rare case of unilateral CNV secondary to punctate inner choroidopathy in a young, myopic male.

Postoperative endophthalmitis is one of the most devastating cataract surgery complications. Our results provide strong evidence of the utility of cefuroxime as prophylaxis of endophthalmitis after cataract surgery.