A new videopupillography

Effects of Toxic Exposure to Molds and Mycotoxins in Building-Related Illnesses

The authors studied 100 patients who had been exposed to toxic molds in their homes. The predominant molds identified were Alternaria, Cladosporium, Aspergillus, Penicillium, Stachybotrys, Curvularia, Basidiomycetes, Myxomycetes, smuts, Epicoccus, Fusarium, Bipolaris, and Rhizopus. A variety of tests were performed on all, or on subgroups of, these patients. Sensitivities and exposures were confirmed in all patients by intradermal skin testing for individual molds (44-98% positive), and by measurement of serum antibodies. Abnormalities in T and B cells, and subsets, were found in more than 80% of the patients. The findings of trichothecene toxin and breakdown products in the urine, serum antibodies to molds, and positive intradermal skin tests confirmed mycotoxin exposure. Respiratory signs (e.g., rhinorrhea, sinus tenderness, wheezing) were found in 64% of all patients, and physical signs and symptoms of neurological dysfunction (e.g., inability to stand on the toes or to walk a straight line with eyes closed, as well as short-term memory loss) were identified in 70% of all patients. Objective abnormal autonomic nervous system tests were positive in all 100 patients tested. Brain scans, conducted using triple-head single photon emission computed tomography, were abnormal in 26 (86%) of 30 (subgroup of the 100) patients tested. Objective neuropsychological evaluations of 46 of the patients who exhibited symptoms of neurological impairment showed typical abnormalities in short-term memory, executive function/judgment, concentration, and hand/eye coordination.

History of chemical sensitivity and diagnosis

Histories of mold, pollen, dust, food, chemicals, and electromagnetic field (EMF) sensitivities are the major categories of triggers for chemical sensitivity. They are tied together by the coherence phenomenon, where each has its own frequencies and identifiable EMF; therefore, they can be correlated. The diagnosis of chemical sensitivity can be done accurately in a less-polluted, controlled environment, as was done in these studies. The principles of diagnosis and treatment depend on total environmental and total body pollutant loads, masking or adaptation, bipolarity of response, and biochemical individuality, among others. These principles make less-polluted, controlled conditions necessary. The clinician has to use less-polluted water and organic food with individual challenges for testing, including dust, mold, pesticide, natural gas, formaldehyde, particulates, and EMF testing, which needs to be performed in less-polluted copper-screened rooms. The challenge tests for proof of chemical sensitivity include inhaled toxics within a clean booth that is chemical- and particulate-free at ambient doses in parts per million (ppm) or parts per billion (ppb). Individual foods, both organic and commercial (that are contaminated with herbicides and pesticides), are used orally. Water testing and intradermal testing are performed in a less-polluted, controlled environment. These include specific dose injections of molds, dust, and pollen that are preservative-free, individual organic foods, and individual chemicals, i.e. methane, ethane, propane, butane, hexane, formaldehyde, ethanol, car exhaust, jet fuel exhaust, and prosthetic implants (metal plates, pacemakers, mesh, etc.). Normal saline is used as a placebo. EMF testing is performed in a copper-screened room using a frequency generator. In our experience, 80% of the EMF-sensitive patients had chemical sensitivity when studied under less-polluted conditions for particulates, controlled natural gas, pesticides, and chemicals like formaldehyde.

Daytime variations in pupil size under photopic conditions

PURPOSE

To assess the daytime variations in pupil size when far and near targets are viewed under photopic conditions.

METHODS

We prospectively examined 20 eyes of 20 healthy subjects [27.3 years ± 4.1 (SD)]. Using an open view-type infrared video pupillometer, pupil sizes were measured in subjects looking at targets 5 m or 1/3 m away under photopic conditions (400 lux). The first measurement was performed at 8.00 h, with following measurements at 3-h intervals until 20.00 h. The average pupil size for 5 s consecutive measurements was used for analysis.

RESULTS

The respective pupil sizes during far and near viewing were 3.80 ± 0.72 and 3.15 ± 0.62 (mean ± SD); 3.73 ± 0.78 and 3.08 ± 0.70; 3.74 ± 0.82 and 3.06 ± 0.68; 3.79 ± 0.67 and 3.17 ± 0.71; and 3.91 ± 0.76 and 3.13 ± 0.70 mm, at 8.00, 11.00, 14.00, 17.00, and 20.00 h. The pupil sizes did not differ significantly with time over the course of the day [far (p 0.94) and near (p 0.98) (one-way analysis of variance)]. The daytime variations of pupil size were 0.64 ± 0.33, and 0.41 ± 0.29 mm, respectively. Two eyes (10%) and one eye (5%) showed differences of more than 1.0 mm during daytime hours in pupil sizes while viewing far and near target, respectively.

CONCLUSIONS

In this study, young adults show no significant variations in photopic pupil size throughout daytime hours. However, a single pupil size measurement appears to be insufficient for clinical use in some eyes.

Application of heat- and steam-generating sheets to the lumbar or abdominal region affects autonomic nerve activity

Effects of applying a heat- and steam-generating (HSG) sheet on peripheral hemodynamics and autonomic nerve activity were examined. An HSG sheet was applied to the lumbar or abdominal region. Measurements included skin temperature at the lumbar and abdominal regions and the fingertip, total hemoglobin, tissue oxygen saturation ratio (StO2), pupillary light reflex, changes in ECG R-R interval blood pressure and percutaneous electrogastrography (EGG). A heat-generating sheet without steam was used as the control. Based on the present findings, application of the HSG sheet to the lumbar or abdominal region may improve peripheral hemodynamics and inhibit sympathetic nerve activity, resulting in parasympathetic nerve activity dominance.

Automated standardized pupillometry with optical method for purposes of clinical practice and research

The aim of the current study was the introduction and standardization of two experimental conditions for dynamic pupillometry. Pupillometry is a method that can provide valuable data concerning the functioning of the autonomous nervous system. The system for recording the pupil reaction was developed in the Laboratory of Clinical Neurophysiology of the 1st Department of Neurology of Aristotle University of Thessaloniki, in co-operation with the Laboratory of Fluid Mechanics of the Aristotle University of Thessaloniki. This system is fully automated. It includes an infra-red video camera, which has the capacity to record in complete darkness, and an SLE (clinical photic stimulator) lamp. A software application automatically performed all the procedures. During the first experiment, one flash was administered. During the second experiment, a series of 25 flashes (1 Hz frequency) was administered. Fifty physically and mentally healthy subjects aged 23-48 years took part in the study. Means, standard deviations and ranges for all variables characterizing normal subjects during both experimental conditions are reported. Test/re-test results and comparisons of the two eyes are also reported. The combined use of these two experimental conditions in dynamic pupillometry may be a very useful tool in medical research. There are already reports on the usefulness of pupillometry in the research of various diseases, including depression and Alzheimer's disease. It is expected that it will also be a valuable research tool in the study of diabetes, alcoholism, myasthenia gravis, cancer, multiple sclerosis, etc.

Clinical evaluation of a 5.5 mm three-zone refractive multifocal intraocular lens

PURPOSE

To evaluate the results of implanting the P359-TUV 5.5 mm three-zone refractive multifocal intraocular lens (IOL).

SETTING

Musashino Red Cross Hospital, Tokyo, Japan.

METHODS

The lens was implanted in 29 eyes of 19 patients who were followed for a mean of 13.5 months. Distance visual acuity (DVA), near visual acuity (NVA), and contrast sensitivity were measured postoperatively.

RESULTS

Ninety-three percent of eyes obtained 20/20 or better DVA with correction and J1 or better NVA with correction. Seventy-nine percent obtained J1 or better NVA with distance correction and 93% obtained J3 or better. Postoperative astigmatism was easier to control than with the former large model multifocal IOL. In almost all cases, good DVA and NVA could be obtained without correction and the cases that did not need spectacle correction increased. In unilaterally implanted cases, contrast sensitivity was slightly less in eyes with multifocal IOLs than in eyes with monofocal IOLs. In bilaterally implanted cases, there was no significant difference in contrast sensitivity between the multifocal and monofocal eyes.

CONCLUSION

The small model P359-TUV lens is an effective multifocal lens, especially when implanted bilaterally.

Evidence for preserved direct pupillary light response in Leber's hereditary optic neuropathy

AIMS/BACKGROUND

Pupillary light response is usually defective in all types of optic neuropathy. However, the authors have observed in patients with Leber's hereditary optic neuropathy (LHON) relatively normal light response, with consequent misdiagnosis psychogenic visual loss in some cases. To confirm this clinical impression, afferent pupillary defect was assessed by measurement of adjusted constriction amplitude (CA) and escape rate (ER) by infrared videopupillography (Iriscorder-C 2515).

METHODS

Thirteen consecutive patients (26 eyes) with LHON (average age 27.2 years) were examined; 12 had the mitochondrial DNA 11778 mutation and one the 14484 mutation. Seven of these patients had a positive family history. For comparison, the above rates were determined in 19 patients (23 eyes) with idiopathic optic neuritis (ON; average age 35.1 years), 18 patients (19 eyes) with anterior ischaemic optic neuropathy (AION; average age 58.1 years), and 25 volunteers (50 eyes) with healthy eyes (average age 39.6 years).

RESULTS

The distribution of visual acuity was essentially the same in all optic neuropathy groups. Reduction in CA and increase in ER were significant in patients with ON and AION, but not in those with LHON. Only slight afferent pupillary defect was evident even 2 years after the onset of LHON. CA in AION and ER in ON were correlated statistically with visual acuity and Humphrey mean threshold deviation, while CA and ER in LHON were not.

CONCLUSION

Pupillary light response in patients with LHON obviously differs from that in patients with other types of optic neuropathy. LHON appears to be pathophysiologically characterised by well preserved afferent fibres for pupillary light response (probably from W cells). Besides being of pathogenetic interest, the detection of clinical features should facilitate the diagnosis of LHON particularly when family history provides no indication.

Leber's hereditary optic neuropathy among Japanese

This article reviews the literature on point mutation of mitochondrial DNA (mtDNA) among Japanese and the authors' research data on pupil reaction in patients with Leber's hereditary optic neuropathy (LHON). Among Japanese, a higher frequency (80-90%) of point mutation at nucleotide position 11778 of mtDNA was found; other point mutations found were at nucleotide positions 3460, 14484, 13708, 7444, and 3394. Although pupil reaction to light stimulus is usually defective in all types of optic neuropathy, in patients with LHON the reaction was well maintained even when vision was reduced. W cells in the retina may be preserved or less damaged, even when the degenerative process progresses in both X and Y cells. Possible treatment is also described.

Low cost Video Scaler and Gray Scale Integrator

A hybrid digital/analog device capable of making high-resolution linear and area measurements from a standard monochromatic video image is described. The device is capable of dynamic as well as static data acquisition when used in conjunction with standard NTSC video recording equipment. Digital output allows for computer interfacing. Linear dimensions are obtained by electronically superimposing two horizontal and two vertical scaling lines on a video monitor. Each linear dimension has an eight-bit resolution and is displayed on the front panel with seven segment LED's. Eight-bit, digital-to-analog converters are also used to provide analog outputs. A measurement of the temporal deformation pattern of the accessory capsule surrounding a mechanoreceptor (Pacinian corpuscles) in response to vibratory displacements is demonstrated. Area measurements are obtained via a window comparator, a 6-MHz clock, and a 16-bit digital-to-analog converter. Data is only valid within the zone set by the scaling lines, allowing data regions to be isolated from noise, etc. The 16-bit digital signal measuring the area of interest is then converted for analog output. The measurement of the consensual pupillary reflex in response to full-field illumination (Ganzfeld) is given as an example.

Automated pupil perimetry. Pupil field mapping in patients and normal subjects

The authors developed an automated method of pupil perimetry by linking an infrared video pupillometer to a Humphrey Field Analyzer. Software was developed to automatically analyze the pupil responses to focal light stimuli and display the results graphically. All 76 locations of Humphrey program 30-2 could be tested twice within 5.5 minutes and the relative sensitivity of the field was determined by comparing the amplitude of pupil constriction or latency time at each stimulus location. The mean pupil responses within annular areas at 3 degrees, 9 degrees, 15 degrees, 21 degrees, and 27 degrees were shown to be linearly related to log stimulus intensity over a 15 dB range under low level mesopic conditions (3.15 asb bowl background). In normal subjects, the superior temporal quadrant usually had the greatest mean pupillomotor response and the inferior nasal quadrant had the least. Pupil responses in the temporal field were larger than corresponding locations in the nasal field. Patients with visual field defects who underwent testing by pupil perimetry showed pupillary deficits in the same location within the field, providing evidence that pupil perimetry may be a useful, objective means of assessing visual field function.

Relationship between age and autonomic neuropathy in diabetes mellitus

The influence of age on diabetic autonomic neuropathy was studied. In the present study autonomic neuropathy was assessed by cardiac beat-to-beat variation during deep breathing (BBV) and pupil area prior to photic stimulus (A1). In the studies on BBV a total of 440 subjects (11-82 years in age) were divided into three groups: those with a duration of diabetes of less than 5 years and without obvious diabetic complications; those with a duration of diabetes of longer than 5 years and with diabetic complications; and non-diabetic, healthy subjects. The relationship between BBV and age was examined in each group. In the studies on A1 a total of 101 subjects (22-75 years in age) were investigated in the same way. The results were as follows: (1) The autonomic nerve function of young diabetics corresponds to that of old non-diabetics in terms of cardiac beat-to-beat variation and pupil area prior to photic stimulus; (2) in young diabetics duration of diabetes and the complications influence the autonomic nerve function; (3) autonomic nerve function is related to age. Age is more influential than duration of diabetes and diabetic complications, especially in the older subjects.

Evaluation of pupil constriction and dilation from cycling measurements

Pupil cycling was produced using an electronic circuit so that the retina was illuminated in Maxwellian view only when pupil area exceeded an adjustable area threshold, Aref. The maximum (Amax) and minimum (Amin) amplitude of the oscillations varied linearly with Aref. These observations are described by a delay-differential equation. The Aref-dependent changes in Amax, Amin were used, respectively, to quantitate dilation and constriction. A comparison of the predicted and observed period of pupil cycling suggests that the latency times for light onset and offset are the same. Measurements of Amax, Amin provide a method for determining the average pupil light response.

Puptrak 1.0--a new semiautomated system for pupillometry with the Octopus perimeter: a preliminary report

A provisional, semiautomated version of a system for automated testing of the afferent pupillary reflex with perimetric methods under controlled conditions is described. The target projected onto the perimeter cupola is used as the stimulus for triggering the pupillary response. In a modification to the Octopus 201, the pupil is illuminated by two IR LED diodes, while the pupillary responses are recorded by the onboard IR sensitive TV camera built into the perimetric unit. Measurements of the pupillary area as a function of time and stimulus luminance have been performed and have resulted in consistent results. Here, one perimetric program, working with stimuli above the threshold for the afferent pupillary light reflex is described. The present setup works with system-specific software and standard hardware, the central data processing unit being a desk-top computer (IBM PC AT-03). The mating of an automated pupillary measuring unit to an automated perimeter may open the door for a more widespread evaluation of the value and the clinical application range of pupillary perimetry and may be of interest in other areas of visual and clinical psychophysics. The shortcomings of the present system, in particular insufficient temporal resolution and lack of full automation, are being removed at the present time.

Irregular pupil cycling as a characteristic abnormality in patients with demyelinative optic neuropathy

We used an infrared videopupillometer combined with an electronic circuit that regulated the retinal light level as a function of pupil area to assess the regularity of pupil cycling in normal subjects and in patients with known abnormalities in the pupil light reflex pathways. The light stimulus was turned on whenever pupil area exceeded a preset value. Two types of abnormalities were observed for patients with demyelinative optic neuropathy: a failure of the pupil to cycle despite a preserved pupillary response to a single light pulse; and, for those patients in whom cycling was possible, a characteristic intermittent irregularity in the amplitude of pupil cycling. These abnormalities were not seen in normal subjects or in patients with ischemic optic neuropathy, surgical lesions involving the optic chiasm, Adie's syndrome, or Horner's syndrome.

A solid-state television pupillometer

An application of an MOS-type solid-state imaging sensor to a television pupillometer is described. Its advantages over the conventional image-tube pupillometers using silicon vidicons are demonstrated with special emphasis on its excellent dynamics performance. Design considerations for an MOS-type solid-state TV camera and the schematic diagram of a pupillometer which detects the horizontal pupillary diameter are presented. Two methods of infrared illumination giving no heat sensation to subjects are also proposed: the effective use of an aquatic filter and solid-state illumination utilizing i.r.-LEDs.

Diagnostic value of objective campimetry

The results obtained in ten normal subjects with a new method of pupillocampimetry are described and compared with those obtained with routine campimetry. Once the relationship between the two methods was established, ten subjects suffering from pregeniculate or postgeniculate lesions of the optic pathways were examined by pupillocampimetry. This study shows the value of this new method, particularly for the differential diagnosis of pre- or postgeniculate lesions.

Infrared video pupillometry: a method used to measure the pupillary effects of drugs in small laboratory animals in real time

Pupillometry in clinical investigation and in basic research often requires dynamic measurement of pupil size. Static methods, i.e. direct observation and still photography, are often used because of the high cost of commercial infrared pupillometers and problems with pupil-iris contrast in small animals. This report describes an improved infrared video pupillometer (IVP) which accurately measures the pupil area of small animals in real time (30 samples/sec). Two components of the pupillometer were designed and built by the authors: a "bright-pupil" infrared illumination system and a digital video signal processor (VSP). The use of a standard closed-circuit television camera to produce the pupil image signal results in a device that is relatively economical to construct. The IVP is sensitive enough to accurately track pupil are in the study of the pupil light reflex or pupillary oscillations. Several applications for the IVP are illustrated, including analysis of the transient response to light flashes and intravenous injections of drug, and analysis of the spontaneous and drug-induced pupillary fluctuation. Pupillography has been applied in the bioassay of various psychopharmacologic compounds and in the assessment of narcotic dependency. This IVP is being used in this laboratory to study the pupillary action of opiates in the rabbit and rat.

Pupillary abnormalities in schizophrenic patients during long-term administration of psychotropic drugs: dissociation between light and near vision reactions

Pupillographic studies were made of the reactions to light and near vision in 12 schizophrenic patients under long-term administration of psychotropic drugs. The results showed a significant reduction in the light reaction, while the near vision reaction was preserved. The pupillographic study revealed not only reduction in amplitude of the light reaction but also changes in dynamic aspects of the reaction, i.e., prolonged latency time, shortened constriction time, and half redilatation time after the light stimulus. The mechanisms underlying the dissociation between light reaction and near vision reaction induced by long-term administration of psychotropic drugs are obscure, but both the peripheral and central actions of these drugs may be involved.

Abnormal pupillary responses in myasthenia gravis. A pupillographic study

Using an open-loop stimulus (Maxwellian view), the direct pupillary response to light and its derivative curves (velocity and accleration of pupillary reactions) were recorded by infrared video pupillography in seven patients with myasthenia gravis and in three normal subjects. Responses before and after intravenous injection of 5 mg edrophonium hydrochloride were determined. Five of the patients had never taken anticholinesterase drugs except for diagnostic injections of edrophonium while the other two patients had been treated with oral preparations of corticosteroids. Analyses of the pupillary responses showed reduced amplitude, amximal velocity, and maximal acceleration of pupillary constriction in the myasthenic patients. On the other hand, changes in parameters of pupillary dilatation were minimal. Abnormal values returned towards normal within five minutes after edrophonium injection in all patients except in one individual who was being treated with corticosteroids at the time of examination. These results suggest that involvement of the iris sphincter may be common in patients with myasthenia gravis and this can be demonstrated by analysing the pupillary reaction and its derivative curves in response to an open-loop stimulus.