Crossed Quadrant Homonymous Hemianopia

Key Points at a Glance

Key Points at a Glance

• Crossed quadrant homonymous hemianopia (CQHH) is an extremely rare visual field defect in which two quadrants on a diagonal are homonymously lost.
• It is also called checkerboard visual field deficit.
• The main cause is embolism of the calcarine artery, arising from branches of the basilar and vertebral arteries.
• The vertical midline is always preserved, and central vision is usually maintained.
• Only 9 cases were reported from 1891 to 1982, making it an extremely rare condition.
• Recovery of visual field defects is difficult, and management focuses on risk factor control and visual rehabilitation.

1. Crossed Quadrant Homonymous Hemianopsia

Crossed quadrant homonymous hemianopsia (CQHH) is a rare visual field defect in which two quadrants on opposite sides of the diagonal are homonymously affected. It is also called “checkerboard visual field deficit.”

It occurs due to lesions above the calcarine sulcus in one occipital lobe and below the calcarine sulcus in the opposite lobe. The defect extends across the horizontal midline, but the vertical midline is always preserved.

History

The first report was by Groenouw in 1891. The patient presented with left hemiparesis and left homonymous hemianopsia, and developed crossed quadrant hemianopsia after a second stroke 10 months later. In 1926, the first case presenting only with ocular symptoms was reported in the British Journal of Ophthalmology.

Epidemiology

According to a review by Cross and Smith, only 9 cases were reported between 1891 and 1982¹. In 2020, Kamal et al. reported a typical case due to bilateral occipital lobe infarction using CT and MRI², and in 2021, Fong et al. reported the first case in a monocular patient³.

Q How rare is crossed quadrantanopia?

A

Only 9 cases were reported over approximately 90 years from 1891 to 1982. As of 2020, only a few new reports due to MS or viper bites exist, making it an extremely rare condition.

2. Main Symptoms and Clinical Findings

Subjective Symptoms

Visual impairment may occur suddenly or progress gradually. Some patients may notice a defect in part of their visual field, but central vision is usually preserved, so the abnormality may go unnoticed. Simple or complex visual hallucinations may appear in the blind spot or within the visible area.

Clinical Findings

Visual field defects occur in the following three patterns.

Simultaneous Onset Type

Two quadrantanopias occur simultaneously: This occurs when lesions develop in both occipital lobes at the same time. It is the most common pattern of onset.

Sequential Recovery Type

Recovery of two homonymous hemianopias to quadrantanopia: Occurs after consecutive strokes, as each homonymous hemianopia partially recovers.

Bilateral recovery type

Simultaneous bilateral homonymous hemianopia recovering to crossed quadrant defects: From extensive visual field defects in the acute phase, only specific quadrants recover.

Characteristics of visual field defects are as follows:

• Preservation of the vertical midline: Defects cross the horizontal midline but the vertical midline is always preserved.
• Preservation of the monocular temporal crescent: Seen when the anterior occipital lobe is spared.
• Preserved quadrant microdefects: Small defect areas may also be observed in the quadrant where the visual field is preserved.
• Color vision abnormality: May be accompanied by cerebral color vision disorder.
• Riddoch phenomenon: A phenomenon in which only moving objects within the blind spot can be perceived. Also called statokinetic dissociation, it can cause apparent discrepancies in visual field testing⁴.

3. Causes and Risk Factors

The most common cause is embolism of the calcarine artery. The calcarine artery is a terminal branch of the posterior cerebral artery and receives blood flow from branches of the basilar artery or vertebral artery. Thromboembolism from heart disease is also a cause.

Other causes reported include the following:

• Cerebral infarction: Infarction in the bilateral posterior cerebral artery territory is most common. Often caused by emboli originating from the vertebral artery.
• Trauma: Associated with cervical spine or vertebral trauma and vascular dissection.
• Multiple sclerosis (MS): There have been reports of bilateral demyelinating lesions. In 1995, Cesareo et al. reported a case from the University of Rome, with MRI confirming lesions in the bilateral geniculocalcarine pathway ⁵.
• Viper bite: Case reports have been made as of 2020.

The main risk factors are as follows:

• Hypertension
• Atherosclerosis
• History of stroke
• Coronary artery disease
• Late-stage syphilis
• Multiple sclerosis
• Trauma

Prevention and Daily Care

Primary prevention of crossed quadrantanopia homonymous hemianopia involves managing risk factors for stroke. Maintain proper control of hypertension, diabetes, and dyslipidemia, avoid smoking, and engage in moderate exercise. If you have a history of stroke, continue antiplatelet or anticoagulant medications as directed by your doctor.

Q Are there other causes besides stroke?

A

Cerebral infarction is the most common cause, but it has also been reported in multiple sclerosis, trauma (cervical or vertebral trauma), and viper bites. All of these involve lesions near the calcarine sulcus in both occipital lobes.

4. Diagnosis and Testing Methods

Diagnosis of CQHH requires visual field testing and head imaging. In monocular patients, there is a risk of missing contralateral asymptomatic quadrantanopia, so caution is needed ³.

Visual Field Testing

• Humphrey Visual Field Analyzer (30-2): This is the recommended automated perimetry for evaluating CQHH. Completely symmetrical results are rare, so a high index of suspicion and careful examination are necessary.
• Goldmann Perimeter: Excellent for detailed evaluation of the peripheral visual field. Detailed peripheral field assessment is essential for occipital lobe lesions, and sparing of the temporal crescent can be confirmed. Even if hemianopia is detected with small stimuli (I/4e or smaller), the visual field may appear normal with the V/4e stimulus.

The main features of visual field testing are shown below.

Test Method	Features	Indications
Humphrey Field Analyzer	Quantitative assessment of central 30°	Screening and follow-up
Goldmann Perimeter	Detailed assessment of peripheral visual field	Evaluation of temporal crescent and definitive diagnosis

Imaging Tests

• MRI: Essential for confirming bilateral occipital lobe infarction. Diffusion-weighted imaging (DWI) can detect hyperacute cerebral infarction as a high-signal area early. FLAIR imaging is useful for distinguishing cerebral infarction from cerebrospinal fluid. In a clinical-anatomical study of 904 cases with homonymous hemianopia, the occipital lobe and optic radiation were the most common lesion sites, consistent with the responsible lesions in CQHH cases⁶.
• CT: Used adjunctively to exclude acute hemorrhagic lesions.

Differential Diagnosis

The following diseases need to be differentiated.

• Stroke: The most frequent cause.
• Tumors: Visual field defects due to compressive lesions.
• Trauma: Posterior cerebral ischemia due to cervical or vertebral trauma.
• Migraine: May present with transient visual field defects.
• Inflammatory processes: Demyelinating diseases such as multiple sclerosis.

5. Standard Treatment

Treatment of CQHH focuses on treating the underlying cause and managing risk factors.

Acute Phase Treatment

For cerebral infarction in the very early stage after onset, consider thrombolytic therapy with t-PA or endovascular treatment. Consultation with a neurologist is recommended.

Pharmacotherapy

Antithrombotic therapy is performed to prevent recurrence of cerebral infarction.

• Antiplatelet drugs: Administer aspirin, etc.
• Anticoagulants: Administer warfarin, etc. This is particularly important when an embolic source such as atrial fibrillation is identified.

Search for the source of embolism is also essential, and evaluation of the heart and aorta is performed.

Visual Rehabilitation

Visual rehabilitation and low vision services are recommended as adaptive training for visual field defects.

• Checkerboard prisms: Used to expand the remaining visual field. They shift the image projected onto the retina on the hemianopic side, making it visible in the seeing area. Effectiveness varies.

Tumor-Related Cases

If there is a tumor-related etiology, a multidisciplinary approach involving neurology, ophthalmology, neuroradiology, and neurosurgery is taken.

Precautions in treatment

Recovery from visual field defects is difficult, and the goal of treatment is to prevent recurrence and support adaptation to daily life. Do not discontinue antiplatelet or anticoagulant medications on your own. Because of the risk of falls and accidents due to visual field impairment, safety measures in daily life are also important.

Q Can visual field defects recover?

A

Recovery from visual field defects due to CQHH is difficult. The goal of treatment is to manage risk factors, prevent further stroke through antithrombotic therapy, and support adaptation to visual field defects through visual rehabilitation. Prognosis is poor in elderly patients, but some recovery may be expected in younger patients.

6. Pathophysiology and detailed mechanism of onset

Anatomy of the visual cortex and correspondence of the visual field

The primary visual cortex (V1) is located on the upper and lower lips of the calcarine sulcus on the medial surface of the occipital lobe. The calcarine sulcus divides it into the upper part (cuneus) and lower part (lingual gyrus), corresponding to the contralateral lower and upper visual fields, respectively. Thus, a lesion above the calcarine sulcus (cuneus) causes contralateral inferior quadrantanopia, while a lesion below the calcarine sulcus (lingual gyrus) causes contralateral superior quadrantanopia.

In CQHH, lesions occur above the calcarine sulcus on one side and below the calcarine sulcus on the opposite side. This results in defects in two quadrants located diagonally.

Vascular Supply and Embolic Mechanism

Most of the blood supply to the visual cortex comes from the calcarine artery, a terminal branch of the posterior cerebral artery. The posterior cerebral artery is a branch of the basilar artery. Therefore, emboli in the vertebrobasilar system can affect both calcarine arteries.

Occlusion of only the calcarine artery results in homonymous hemianopia as the sole symptom, while occlusion of the main trunk of the posterior cerebral artery is accompanied by thalamic syndrome (contralateral sensory disturbance).

The occipital pole receives dual blood supply from the posterior cerebral artery and the middle cerebral artery. This dual supply is considered one of the causes of macular sparing, and is one reason why central vision is often preserved in CQHH.

Characteristics of Visual Field Defects in Occipital Lobe Lesions

Visual field defects caused by occipital lobe lesions have the following characteristics.

• High congruity: The shape of the visual field defect is very similar between the left and right eyes. It is more congruent than other visual pathway disorders.
• Extension ignoring the horizontal meridian: Occipital lobe infarcts often spread regardless of the calcarine sulcus, resulting in visual field defects that cross the horizontal meridian.
• Macular sparing: This is attributed to dual blood supply to the occipital pole and the large cortical area corresponding to the macula.

Complications

• Cortical blindness: Caused by extensive damage to both occipital lobes. The pupillary light reflex is normal, but visual impairment is present.
• Anton syndrome: A phenomenon in which patients with cortical blindness deny their own blindness. It is seen in posterior cerebral artery territory infarction involving the primary visual cortex and association areas.
• Riddoch syndrome: A phenomenon in which patients with occipital lobe lesions of the striate cortex are only aware of moving objects within the blind spot. Also called statokinetic dissociation.

7. Latest Research and Future Perspectives (Research Stage Reports)

For patients: Please read this

The following content is currently in the research stage or under clinical trials and is not standard treatment available at general hospitals. It is reference information for professionals regarding future medical developments.

Walking Assistance Using Mixed Reality Glasses

The effectiveness of mixed reality glasses (MRG) equipped with a picture-in-picture navigation function is being studied in patients with homonymous hemianopia. Research has shown that although walking speed decreased slightly, patients’ attention improved and walking ability improved slightly. However, no studies specific to CQHH have been conducted yet.

The introduction of electronic devices and AI-based tools has shown usefulness in some patients with visual field defects, but further research is needed for CQHH.

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8. References

Footnotes

1. Cross SA, Smith JL. Crossed-quadrant homonymous hemianopsia. The “checkerboard” field defect. J Clin Neuroophthalmol. 1982;2(3):149-158. PMID: 6217217 ↩

2. Kamal S, Al Othman BA, Kini AT, Lee AG. Checkerboard Visual Field Defect in Occipital Stroke. J Neuroophthalmol. 2020;40(2):e13-e14. doi:10.1097/WNO.0000000000000892. PMID: 32028451 ↩

3. Fong JW, Ly VV, Braswell RA. Crossed-quadrant homonymous hemianopsia in a monocular patient. Can J Ophthalmol. 2021;56(4):e129-e131. doi:10.1016/j.jcjo.2021.02.004. PMID: 33667430 ↩ ↩²

4. Hayashi R, Yamaguchi S, Narimatsu T, Miyata H, Katsumata Y, Mimura M. Statokinetic Dissociation (Riddoch Phenomenon) in a Patient with Homonymous Hemianopsia as the First Sign of Posterior Cortical Atrophy. Case Rep Neurol. 2017;9(3):256-260. doi:10.1159/000481304. PMID: 29422846 ↩

5. Cesareo M, Pozzilli C, Ristori G, Roscioni AM, Missiroli A. Crossed quadrant homonymous hemianopsia in a case of multiple sclerosis. Clin Neurol Neurosurg. 1995;97(4):324-327. PMID: 8599901 ↩

6. Zhang X, Kedar S, Lynn MJ, Newman NJ, Biousse V. Homonymous hemianopias: clinical-anatomic correlations in 904 cases. Neurology. 2006;66(6):906-910. doi:10.1212/01.wnl.0000203913.12088.93. PMID: 16567710 ↩