Visual field testing

Testing Methods

Confrontation Testing

Manual field testing

- Examiner faces patient at 1 meter

- Tests each eye separately

- Compares patient's field with examiner's

- Targets moved from non-seeing to seeing areas

Kinetic Perimetry

Goldmann Perimetry

- Moving stimulus of known intensity

- Maps isopters (lines of equal sensitivity)

- Multiple stimulus sizes and intensities

- Bowl radius: 33cm

Static Perimetry

1. Humphrey Field Analyzer

- Standard automated perimetry

- Fixed stimulus locations

- Threshold testing

- Background illumination: 31.5 asb

2. Octopus Perimeter

- Automated static perimetry

- Multiple testing strategies

- LED stimulus presentation

- Customizable test patterns

Standard Testing Protocols

Central Field Testing

- 24-2 protocol (central 24 degrees)

- 30-2 protocol (central 30 degrees)

- 10-2 protocol (central 10 degrees)

- Macular program

Peripheral Field Testing

- 60-4 protocol

- Full field 120 points

- Temporal crescent

Testing Parameters

Stimulus Specifications

- Size: Goldmann I-V

- Duration: 200ms standard

- Background illumination: 31.5 asb

- Maximum intensity: 10,000 asb

Fixation Monitoring

1. Blind spot monitoring

2. Gaze tracking

3. Video monitoring

4. False positive/negative catches

Result Analysis

Key Metrics

1. Mean Deviation (MD)

2. Pattern Standard Deviation (PSD)

3. Visual Field Index (VFI)

4. Global Indices

Reliability Indices

- Fixation losses

- False positives

- False negatives

- Test duration

Clinical Applications

Primary Diagnoses

1. Glaucoma

- Early detection

- Progression monitoring

- Treatment effectiveness

2. Neurological Conditions

- Tumors

- Stroke

- Optic neuritis

- Multiple sclerosis

3. Retinal Disorders

- Retinitis pigmentosa

- Diabetic retinopathy

- Macular degeneration

Monitoring and Management

1. Disease Progression

- Serial field analysis

- Progression analysis

- Event vs. trend analysis

2. Treatment Response

- Pre/post intervention

- Medical therapy monitoring

- Surgical outcome assessment

Common Field Defects

Pattern Recognition

1. Nerve Fiber Layer Defects

- Arcuate defects

- Nasal step

- Paracentral scotoma

2. Neurological Defects

- Hemianopia

- Quadrantanopia

- Bitemporal defects

3. Retinal defects

- Altitudinal defects

- Central scotoma

- Ring scotoma

Special Considerations

Patient Factors

1. Age considerations

2. Physical limitations

3. Cognitive status

4. Fatigue effects

Technical Factors

1. Refractive correction

2. Pupil size

3. Lens opacity

4. Ambient illumination

Documentation and Reporting

Essential Elements

1. Test parameters

2. Reliability indices

3. Global indices

4. Pattern analysis

5. Progression data

Quality Assurance

1. Regular calibration

2. Standardized procedures

3. Staff training

4. Environment control

Conclusion

Visual field testing remains a cornerstone of orthoptic assessment, providing crucial information for diagnosis, monitoring, and management of various ocular and neurological conditions. Understanding proper testing procedures, interpretation, and clinical applications is essential for accurate patient care.

Note : This document serves educational purposes exclusively and does not constitute medical advice or treatment guidelines