Retrobulbar neuritis as the first sign of the glucagonoma syndrome

A 63-year-old man with a metastasising pancreatic glucagonoma is described, who presented with progressive deterioration of vision and bilateral central scotomata as the first symptom. This patient was treated with dacarbazine (DTIC) 250 mg/m2 IV daily for five consecutive days at 4-week intervals. The vision returned completely to normal, in a clinical and biochemical remission. Although there is no wide experience in treatment, the literature seems to indicate that DTIC should be the drug of choice in treating metastatic glucagonoma. Central scotomata may be a new 'paraneoplastic' symptom and a key to the earlier diagnosis of the glucagonoma syndrome by ophthalmologists, just as necrolytic migratory erythema has been for the dermatologists.

Effects of stimulation of the ocular sympathetic nerves on IOP and aqueous humor flow

Ocular sympathetic nerves were stimulated chronically in awake rabbits using electrodes unilaterally implanted on the cervical sympathetic trunk. IOP was measured by pneumatonometry and aqueous inflow was measured by fluorophotometry. In each animal, continuous trains of 1 msec pulses were delivered by means of a portable electrical stimulator. Experiments were spaced by 1 week recovery periods. Stimulation was varied over a range of amplitudes (5-15 V) and frequencies (3-12 Hz). Continuous sympathetic stimulation produced an immediate sharp decrease in IOP followed by a gradual rise to pre-stimulation values which were attained 60-90 min after onset. A rebound increase in IOP occurred when stimulation was terminated. The magnitude of the initial IOP drop, the delay in the return to pre-stimulation IOP, and the rebound rise in IOP subsequent to termination of electrical stimulation were proportional to the stimulation frequency. Maximal effects were observed at 12 Hz, and stimulation with 8-10 Hz for 180 min caused a sustained reduction in anterior chamber aqueous humor flow. Topical 2% phentolamine 1 hr before stimulation markedly reduced IOP and abolished the acute IOP changes observed in untreated stimulated animals. Topical 1% timolol did not affect either the initial IOP drop or the rebound; however, the IOP recovered during stimulation to values greater than pre-stimulation IOP. We conclude that in rabbits the beta-adrenergic effect of prolonged sympathetic nerve stimulation is to decrease aqueous flow. Chronic electrical stimulation in awake animals provides an experimental model for studying the role of the ocular sympathetic nerves.

Adrenergic decentralization modifies the circadian rhythm of intraocular pressure

The effect of unilateral decentralization on the circadian rhythm of IOP was examined in rabbits to determine whether postganglionic sympathetic nerves to the eye can play a role in regulating the circadian rhythm of IOP in the absence of input from the central nervous system. Decentralization produced a marked reduction of the dark phase increase of IOP, but had little effect on IOP during the light phase. Therefore, circadian signals from the central nervous system, which contribute to the dark phase increase of IOP, arrive at the cervical ganglia by way of preganglionic fibers of the sympathetic chain and travel to the eye through postganglionic adrenergic nerves.

FMRF-amide-like immunoreactive efferent fibers and FMRF-amide suppression of pacemaker neurons in eyes of Bulla

The eyes of certain marine gastropods including Aplysia and Bulla, contain circadian pacemakers, which produce a circadian rhythm of autogenous compound action potential (CAP) activity. The CAPs are generated by the synchronous spike discharge of a distinctive population of retinal pacemaker neurons whose axons convey the CAP activity to the CNS. When CAP activity is recorded from a preparation with eyes attached to the CNS, the CAP activity is modulated by efferent activity. In this study we have identified FMRF-amide-like immunoreactive efferent axons in the optic nerves of Bulla. These axons arborize in the basal retinal neuropil adjacent to the pacemaker neurons and are in a position to make synaptic contacts with their dendrites. Similar immunoreactive fibers are not observed in Aplysia eyes. Exogenous FMRF-amide at micromolar concentrations suppresses ongoing CAP activity in isolated eyes but does not suppress the ERG or phase shift the circadian rhythm of CAP activity. Intracellular recordings from the retinal pacemaker neurons reveal that FMRF-amide hyperpolarizes the membrane potential, suppresses spike discharge, and decreases the input resistance, suggesting that a K conductance is increased. Electrical stimulation of the region of the cerebral ganglion that contains FMRF-amide immunoreactive neurons suppresses ongoing CAP activity. All these results are consistent with the idea that the FMRF-amide immunoreactive central neurons and their axons provide a pathway for efferent modulation of the CAP rhythm generated by the retinal pacemaker neurons.

Accommodative hysteresis: influence on closed loop measures of far point and near point

The study examined accommodative hysteresis under closed loop viewing conditions. After sustained focus for 8 min at either the far-point (FP) or near-point (NP) of accommodation, subjects exhibited hysteresis-like shifts in tonic accommodation, ie, dark focus (DF), in the direction of the fixation target. Measurement of NP and FP before and after the focusing period showed that only the position of the NP was significantly influenced, in a direction matching that of the DF. The NP shifted outward by 0.37 diopters (D) and inward by 0.62 D after sustained FP and NP focusing respectively. Control conditions in which subjects focused on a target at the dioptric distance of the DF or were exposed to an 8 min dark interval showed no changes in either NP, FP or DF. The ready susceptibility of the NP to hysteresis effects suggests a potential contributing role of these phenomena to near-work-induced myopia by way of increased accommodative amplitudes with attendant increases in scleral and/or choroidal stress.

Regulation of synaptic frequency: comparison of the effects of hypoinnervation with those of hyperinnervation in the fly's compound eye

At the anterior rim of the first optic neuropile, or lamina, of the housefly's (Musca domestica) compound eye, the terminals of photoreceptors (R) innervate postsynaptic neurons in variable numbers to provide a continuous range of natural hypo- and hyperinnervations. Frequencies of photoreceptor synapses have been measured from quantitative electron microscopy on single sections of the lamina's unit synaptic modules, called cartridges. These are normally innervated by six photoreceptor terminals (6R cartridges). At the lamina's edge hypoinnervated cartridges (2R-5R) are found, whereas hyperinnervated cartridges (7R, 8R) are located at the equator between dorsal and ventral eye halves. In 2R cartridges each presynaptic terminal forms up to 1.5 times the normal, 6R cartridge number of synapses, thereby offsetting the reduced number of terminals and partially conserving the input upon the postsynaptic neurons. Thus the terminals have a reserve synaptogenic capacity never normally revealed. By comparison, terminals in 8R cartridges form about the same numbers of synapses as in "normal" eye regions, so that their postsynaptic neurons have a synaptic input increased by the extra number of terminals. The number of synapses formed between input terminals and target neurons is therefore not fixed but changes as a function of the total receptor terminal complement. The size of a photoreceptor terminal covaries to a certain extent with the number of its presynaptic sites; the spacing density of presynaptic sites over the terminals' surface in a 2R cartridge compared with an 8R cartridge increases far less (only 17%) than the increase in the number of sites (43%). The pair of postsynaptic cell interneurons in each 2R cartridge also shows a decrease in axonal diameter compared with those in 8R cartridges. Thus both the pre- and postsynaptic cells show size changes correlated with changes in their synaptic engagement.

Retrograde transport of endogenous nerve growth factor in superior cervical ganglion of adult rats

The concentration of naturally synthesized nerve growth factor (NGF) was measured in various tissues of adult rats, using a highly sensitive two-site enzyme immunoassay. The highest concentration was found in the superior cervical sympathetic ganglion (SCG). Transection of the postganglionic external carotid nerve (ECN) reduced the ganglionic level of NGF more than did section of the internal carotid nerve (ICN). When both the preganglionic nerve and the ECN were cut, the ganglionic NGF level decreased even more. On the other hand, when the preganglionic nerve and the ICN were both sectioned, leaving the ECN intact, endogenous NGF content in the SCG was significantly enhanced 3-9 h after operation. Bilateral extirpation of submaxillary gland produced a rapid decrease in ganglionic NGF 3-6 h after operation, and even unilateral removal of one salivary gland caused a decrease in both ganglia, which was however much greater in the ipsi- than in the contralateral ganglion. Removal of the eyeballs caused a much smaller reduction in ganglionic NGF than did removal of the glands. These results suggest that the endogenous NGF that accumulates in the SCG is mostly synthesized in the submaxillary gland rather than in the iris, and that it is transported to the SCG, mostly via the ipsilateral ECN.

Retinofugal sprouting of ipsilateral projections in rat

Expansion of ipsilateral retinal inputs into terminal regions of the primary was assessed in rats enucleated at birth or as adults. In addition, one animal with a congenital absence of one eye received an injection of the label into the remaining eye and was similarly processed. Analysis of the sections revealed an increase in retinal inputs, relative to control injections, in the lateral geniculate nucleus and the superior colliculus. The increase observed in the brains of animals receiving enucleation at birth was greater than the increase observed after eye removal in the adult, although the greatest increase was observed in the animal with the congenital loss of one eye. Differences in the sprouting response within the various terminal areas as well as the age related decrease in the ability of retinofugal axons to sprout into denervated visual areas in the brain are discussed.

Autonomic neurons supplying the rat eye and the intraorbital distribution of vasoactive intestinal polypeptide (VIP)-like immunoreactivity

We traced the origin and path of autonomic nerves to the rat eye using, as an aid to dissection, a modified thiocholine method for the histochemical demonstration of cholinesterase. When applied to whole nerves and ganglia supplying the rat eye, this procedure is not specific for cholinergic neurons; instead it stains both sympathetic and parasympathetic nerves, many of which are otherwise too fine to identify in dissection. We found that nerves from the superior cervical and pterygopalatine ganglia form a plexus at the orbital apex corresponding to the retro-orbital plexus found in rabbit, monkey and man. In the rat, nerves from the retro-orbital plexus travel peripherally to the superior surface of the optic-nerve sheath. Here, they fuse with long ciliary nerves and the post-ganglionic nerves from the ciliary ganglion to form another dense nerve-fiber plexus that ultimately supplies the eye. Importantly, the plexus on the optic nerve contains many isolated or aggregated ganglion cells. These are comparable in number to those in the ciliary ganglion itself and are assumed to be accessory ciliary neurons. Using immunohistochemistry, we also sought evidence for vasoactive intestinal polypeptide in these ganglia and nerves. As previously known, many pterygopalatine ganglion cells are immunoreactive for this peptide. Vasoactive intestinal polypeptide (VIP)-like immunoreactive nerve fibers are present in nerves from the retro-orbital plexus to the optic-nerve sheath plexus, in most nerves of the latter plexus, and in most nerves entering the eye. Furthermore, a small proportion of nerve cells in the main and accessory ciliary ganglia also are immunoreactive for VIP. We conclude that in addition to the pterygopalatine ganglion, the ciliary ganglion and its accessory ganglia are sources of VIP-like immunoreactive nerves in the rat eye.

The functional organization of the crayfish lamina ganglionaris. II. Large-field spiking and nonspiking cells

The functional properties of the multicolumnar interneurons of the crayfish lamina ganglionaris were examined by intracellular recording and the cell structures were revealed with the aid of Lucifer yellow or horseradish peroxidase iontophoresis. The multicolumnar monopolar cell M5 responds to a light pulse with a depolarizing compound EPSP and a burst of action potentials. Both the EPSP amplitude and the spike rate decay toward a lower level plateau in less than 200 ms after light onset. M5 is subject to surround inhibition, which is associated with a compound IPSP and net hyperpolarization of the membrane potential. Direct depolarization of M5 may provide a weak excitatory drive to medullary sustaining fibers (SF). Tangenital-cell type 1 (Tan1) has a broad expanse of neurites in the lamina (covering 10 to 15 cartridges) and a much narrower projection in the medulla (1 to 3 cartridges). The response to a light pulse has a long latency consistent with a polysynaptic receptor to Tan1 pathway. The response consists of a nearly rectangular hyperpolarization. Light 'off' elicits a depolarization and a burst of impulses. The polarity of the 'on' response can be reversed by hyperpolarizing the membrane by 23 mV. The receptive field is broad and the intensity-response function exceeds 4 log units. Direct hyperpolarization of Tan1 provides a strong excitatory signal to medullary SFs both in the dark and in the presence of illumination. We propose that Tan1 provides the principal steady-state excitatory drive to the SFs. Tangential-cell type 2 (Tan2) is distinguished from Tan1 by the extent and shape of the lamina process, which is a vertically oriented neurite spanning most of the lamina in a single plane. Functionally, Tan2 is similar in most respects to Tan1, but the response latency is much shorter, comparable to that of monopolar cells. T-cells may exhibit spontaneous impulse activity in the dark which is inhibited by a short latency hyperpolarizing light response. The receptive field, which is about 2 X larger than that of the columnar monopolar cells, is correlated with a small but multicolumnar dendritic arbor in the lamina. Since T-cells are aminergic, it is possible that the amines are normally released in the dark. A single amacrine cell was fully characterized. It exhibited a short latency hyperpolarizing response to light onset and a strong depolarizing 'off' response.(ABSTRACT TRUNCATED AT 400 WORDS)

Brain stem anesthesia after retrobulbar block

Presented is a series of eight patients in whom neurologic sequelae developed after retrobulbar anesthesia. All patients demonstrated blockade of one or more cranial nerves and six progressed to apnea, requiring intubation and mechanical ventilation. Neurologic findings included amaurosis in the contralateral eye (5 patients), nonreactive pupil in the contralateral eye (6 patients), ductional defects (2 patients), and dysphagia (4 patients). In all cases, these findings resolved in 2 to 12 hours. In patients who progressed to apnea, spontaneous respiration resumed within 30 to 60 minutes. These findings are particularly significant in light of recent decisions to reduce anesthesia coverage for cataract surgery in some regions.

The functional organization of the crayfish lamina ganglionaris. I. Nonspiking monopolar cells

The light responses of the second order lamina monopolar neurons were examined in the crayfish compound eye. Single cartridge monopolar neurons (M1-M4) exhibited nonspiking hyperpolarizing light responses; for M1, M3 and M4 the transient 'on' response operated over the same intensity range as the receptor, 3.5 log units. M2 operated in a much narrower intensity range (1.5 log unit). The 'on' responses were associated with a 19% increase in conductance. The hyperpolarizing 'on' response can be reversed at 18 mV below the resting membrane potential. The half-angular sensitivity width of monopolar cells (in partially dark-adapted eyes) is 15 degrees X 8 degrees (horizontal by vertical). Off axis stimuli elicit attenuated hyperpolarizing responses associated with a diminished conductance increase or depolarizing responses associated with a net decrease in conductance. The latter result is consistent with the presynaptic inhibition of a 'back-ground' transmitter release which normally persists in the dark. Lateral inhibition is elicited from the area immediately surrounding the excitatory field, and it is associated with diminished transient responses and an accelerated decay of the response. Inhibitory stimuli decrease the conductance change associated with the hyperpolarizing response. The surround stimuli can also elicit depolarizing 'off' responses with reversal potentials positive to the membrane resting potential. It is concluded that the rapidly repolarizing monopolar cell response is modulated by both pre- and postsynaptic inhibitory mechanisms. A compartment model indicates that signal attenuation along a 500 microns length of monopolar cell axon is 22-34%. Simulation of steady-state signal transmission suggests that passive (decremental) conduction is sufficient to convey 66 to 78% of the monopolar cell signal from lamina to medulla. The current-voltage relation in current clamp is linear over the physiological operating range, and there is no evidence for rectification. Hyperpolarization of single monopolar cells (M1-M4) provides a polysynaptic excitatory signal to the medullary sustaining fibers.

The intra-ocular portion of the optic nerve in the turtle Mauremys caspica

The cytoarchitecture of the intra-ocular optic nerve was investigated by light and electron microscopy. Glial cells in the intra-ocular portion are disposed among the axons, either scattered or forming columns, and bordering the nervous parenchyma. Astroglia forms the limiting glia that separates the optic nerve from the vitreous body, retina, choroid and sclera. Indentations of choroid-scleral tissue are observed in the limiting glial sheet as well as an abundance of hemidesmosomes in the astrocytic plasma membranes that abut onto the basal lamina. At the scleral level there is no connective tissue structure similar to the mammalian lamina cribrosa. However, astrocytes in this region are regularly arranged in thick columns and their processes cross throughout the nerve perpendicular to the axons, forming a framework through which the nerve fibres pass. Numerous myelinated and unmyelinated axons are present in the intra-ocular portion. Oligodendrocytes are also present in close relation with myelinated axons. A deep connective tissue septum arises from the ventral region of the optic nerve and extends along the intra-ocular portion.

A quantitative correlation of substance P-, calcitonin gene-related peptide- and cholecystokinin-like immunoreactivity with retrogradely labeled trigeminal ganglion cells innervating the eye

To evaluate the intraganglionic organization of ocular sensory neurons in the guinea pig, we studied the retrograde axonal transport from the eye to the trigeminal ganglion of cholera toxin B subunit and then applied immunohistochemistry for substance P, calcitonin gene-related peptide and cholecystokinin. Retrogradely labeled cells were observed only in the anteromedial portion of the ipsilateral ganglion. We observed no somatotopical organization to trigeminal neurons containing any of these three peptides, either for cells projecting to the eye or for the ganglion as a whole. The relative proportion of neurons immunoreactive for each of these three peptides was similar among the population of neurons retrogradely labeled with cholera toxin B and among the population of neurons without direct projections to the eye.

Spread of HSV-1 to the mouse eye after inoculation in the skin of the snout requires an intact nerve supply to the inoculation site

Infection of the eye following inoculation of herpes simplex virus on the skin of the snout was monitored using slit lamp examination of the eye, isolation of virus from eyewashings and identification of virus antigens in whole corneal epithelial sheets by peroxidase-antiperoxidase staining. Infection of the eye was prevented by removing a section of the sensory nerves which supply the inoculation site. This provided evidence that spread from the skin of the snout to the eye occurred via the nerves.

Tonic accommodation, cognitive demand, and ciliary muscle innervation

An infrared optometer was used to investigate the relation between cognitive induced shifts in tonic accommodation (TA) and ciliary muscle innervation. Twenty emmetropic men volunteers took part in a double-masked protocol which involved high (a reverse counting task) and low levels of mental load and blocking of sympathetic innervation of the ciliary muscle with the nonselective beta receptor antagonist timolol maleate (0.5%). The high level of cognitive demand induced shifts in TA of up to +1 D. There was no clear reason why large differences in intersubject susceptibility to these shifts occurred. The effect of beta-antagonism on these shifts was insignificant for subjects having initial TA values less than 1.2 D. However, sympathetic antagonism induced significant increases in cognitive shifts for the remaining subjects. The inference is that cognitive induced shifts in TA are predominantly parasympathetic mediated although a sympathetic attenuation may occur at higher levels of TA.

Autonomic drug effects after chronic lowering of ocular cholinergic input. I. Pupillary responses

Cholinergic input to the anterior segment of the eye was chronically lowered by ciliary ganglionectomy in cats. Experimental eyes developed supersensitivity to the miotic effects of pilocarpine. In addition, these parasympathetically denervated eyes exhibited a moderate subsensitivity to the mydriatic effects of norepinephrine, epinephrine, and isoproterenol. Iris preparations accordingly afford the unique opportunity to study the two opposite extremes of normal drug sensitivity simultaneously in the same tissue.

Identifying HSV infected neurons after ocular inoculation

ICR mice were inoculated intracamerally with McKrae strain herpes simplex virus (HSV) followed by intraperitoneal injection with 3H-thymidine. Infected mice were sacrificed after 3 or 4 days and the eyes, trigeminal ganglia (TG) and superior cervical ganglia (SCG) were embedded in glycol methacrylate, sectioned, and dipped for autoradiography. Light microscopy revealed silver grain labeling over neurons in the ipsilateral retina, TG and SCG of infected animals. No labeling of neurons was noted in the contralateral TG or SCG. Since the DNA of mature neurons does not replicate, we interpret these labeled neurons to represent cells with active replication of HSV. This technique allows the study of HSV infection of the nervous system with excellent tissue preservation. Furthermore, it may be used to distinguish those neurons with intrinsic viral synthesis from those harboring virus synthesized at a distant site with subsequent intracellular spread.

Chronic stimulation of ocular sympathetic fibers in unanesthetized rabbits

The goal of this study was to devise a technique to implant permanent electrodes in the cervical sympathetic trunk, to stimulate the ocular adrenergic fibers for periods of hours or days in awake, unrestrained rabbits. Electrodes were made of a silver wire soldered to a multistranded wire and enclosed in silicone. Two of these electrodes were wrapped around the preganglionic sympathetic nerve, their leads emerging through a hole in the back of the neck. Success of the procedure was confirmed by the mydriasis elicited by electrical stimulation of the nerve following surgery; threshold voltages for the pupillary response varied between 5-10 volts. In eight rabbits, suprathreshold sympathetic stimulation was performed on the following days by means of a portable stimulator using increasing frequencies (1, 3, 5, 8, and 10 Hz) during a 20-hr period. Dilation of the ipsilateral pupil and vasoconstriction in the ear, measured by the fall in temperature of the ear's surface, was observed as long as stimulation was maintained. Both effects were proportional to the frequency of stimulation. Maximal mydriasis was obtained at 8 Hz, whereas full vasoconstriction was elicited with 5 Hz. Intraocular pressure, measured in 10 rabbits with a Perkins tonometer at the end of a 24-hr stimulation period, did not differ from pre-stimulation values. It was concluded that chronic stimulation of the sympathetic nerve allows to maintain known levels of adrenergic activity in the eye, and may be a useful method to study the actions of the adrenergic system on various ocular functions in unanesthetized animals.

Calcitonin gene-related peptide in the eye: release by sensory nerve stimulation and effects associated with neurogenic inflammation

Calcitonin gene-related peptide (CGRP) in the anterior uvea coexists with tachykinins (substance P and neurokinin A) in sensory nerve fibers deriving from the trigeminal ganglion. Mechanical or electrical stimulation of the intracranial part of the trigeminal nerve/ganglion in rabbits produced a marked hyperemia in the anterior segment of the eye, increased intraocular pressure, breakdown of the blood-aqueous barrier and miosis. Simultaneously, CGRP-like immunoreactivity was released into the aqueous humor. This suggests that the highly vasoactive CGRP can be released from sensory nerve fibers to participate in vascular responses. Unlike the tachykinins, CGRP per se was without effect on the pupillary diameter while disrupting the blood-aqueous barrier (resulting in aqueous flare) upon intravitreal injection. In addition, CGRP enhanced the aqueous flare evoked by a minimal eye trauma (infrared irradiation of the iris). The miosis evoked by the intravitreal injection of substance P was more pronounced when CGRP was injected simultaneously, and finally, substance P induced aqueous flare much more effectively when given together with a threshold dose of CGRP.

Ultrastructure of capitate projections in the optic neuropil of Diptera

Photoreceptor axons in the first optic neuropil of the dipteran flies Musca domestica and Drosophila melanogaster was examined with electron microscopy. The objective was to determine ultrastructure, persistence and glial source of the capitate projections found within these neurons. Capitate projections are simple or compound processes of epithelial glial cells which profusely insert into form-fitting folds of axon terminals of the peripheral retinular cells (R1-6) in the synaptic plexus portion of the first optic neuropil. These neuro-glial junctions may be simple indentations, have a head with a single stalk, or possess a single, circular stalk from which 3 or 4 bulbous (glial) heads are elaborated. Using serial thick sections of Drosophila neuropil for HVEM we were able to observe that the stalks connecting nearly all capitate projections led directly to a glial cell. Thus no disembodied heads were found suspended in axoplasm. Capitate projections appeared to be persistent structures, present in young as well as senescent adults. No evolution of form was found; thus 3 distinct expressions of these glial processes (without transitional forms) are present. From freeze-fracture replicas and serial HVEM sections it was determined that there were approximately 3 capitate projections per micron 2 in Drosophila and Musca, respectively. About 800 capitate projections exist per Musca axon terminal or about 5 times the number of chemical synapses. Cp's were slightly larger in Drosophila than in Musca, although the Musca retinular axon has twice the diameter and length of that of the fruit fly. The evidence was reviewed in light of the likely supportive function of capitate projections on the R1-6 terminals.

HSV-1 recovery from ocular tissues after viral inoculation into the superior cervical ganglion

New Zealand albino rabbits were inoculated in the right superior cervical ganglion with 25 microliter of herpes simplex virus type 1 (HSV-1) (McKrae strain; 10(3) or 10(5) PFU/ml). Positive tear film swabs were detected at least once in 28/32 (88%) of ipsilateral eyes and 6/32 (19%) of contralateral eyes beginning on postinoculation (PI) day 2-6. The average HSV-1 titer in the tear film was 4.0 X 10(3) PFU in ipsilateral eyes and 2.7 X 10(3) PFU in contralateral eyes, determined from eye washes after inoculation of 25 PFU of HSV-1. In selected rabbits, the aqueous humor was positive for virus on PI days 3, 4, 5, 6, and 8. the aqueous humor in ipsilateral eyes showed positive results in 9/11 (82%) of the eyes tapped on PI 3, 13/18 (72%) on PI 4, 5/11 (45%) on PI 5, 1/6 (17%) on PI 6, and 1/2 (50%) on PI 8. No virus was detected in aqueous humor tappings in any contralateral eyes (0/65). Conjunctivitis and iritis (iris hyperemia) appeared in all ipsilateral eyes beginning as early as PI day 1. Conjunctivitis occurred in 1/21 (4.8%) of contralateral eyes. Cells and flare appeared in 18/21 (86%) of ipsilateral eyes and 2/21 (9.5%) of contralateral eyes. Hyphema was noted in 3/21 (14%) of ipsilateral eyes. Of the eyes with iritis, 12/21 (57%) developed corneal edema. Corneal dendritic ulcers were observed in 4/21 (19%) of ipsilateral eyes and 2/21 (9.5%) of contralateral eyes. No ocular fundus changes were seen in any contralateral or ipsilateral eyes.(ABSTRACT TRUNCATED AT 250 WORDS)