From Lesions to Perception: The Triangular Tale of Balint-Holmes Syndrome

Sejal R Singh, M. Optom

Research Optometrist, Sankara Nethralaya, Chennai, India

 

Balint’s syndrome, also known as Balint-Holmes syndrome, manifests as a triad comprising optic ataxia, oculomotor apraxia, and simultagnosia. This rare and debilitating condition typically arises in the presence of bilateral lesions in the parietal lobes. ⁽¹⁾ The most common cause of these lesions is watershed infarction resulting from cerebral hypoperfusion at the site of the posterior and middle cerebral arteries, which are especially vulnerable to cardiac arrest and hypoperfusion. ⁽²⁾

Figure 1: Balint’s Syndrome Triad
Image Courtesy: https://www.AdeWijaya5/balint-syndrome

This condition gives rise to a triad of symptoms (Figure 1): ⁽¹⁾

1. Oculomotor Apraxia: Impaired capacity to intentionally direct eye movements toward a specific object.
2. Optic Ataxia: Difficulty in accurately reaching for objects within the visual field.
3. Visual Simultagnosia: Inability to perceive the entire visual scene. In Balint’s syndrome, one can only perceive fragments of the whole picture.

One of the three characteristics that characterises Balint syndrome is the incapacity of the patient to use visual information to control their hands or eyes due to a lack of synchronisation between their visual inputs and motor outputs. Individuals with this syndrome can name colours and objects, do not have paralysis of extraocular movement, and have normal visual acuity. ⁽¹⁾

Causal Chronicle

Although unilateral illness has been reported, bilateral symmetric lesions in the parietal (Figure 2) and occipital regions are the most common cause of Balint syndrome. ⁽²⁾ Numerous other conditions have been linked to the condition, including infectious diseases like Creutzfeldt-Jakob disease (CJD), subacute HIV encephalitis, and cerebral toxoplasmosis; neurodegenerative diseases like Alzheimer’s disease, posterior cortical atrophy/the visual variant of the disease, and cortical basilar degeneration; posterior reversible encephalopathy syndrome (PRES); progressive multifocal leukoencephalopathy (PML); primary central nervous system angiitis; cerebral adrenoleukodystrophy; brain metastases. ⁽³⁾

Figure 2: Parietal Lobe
Image Courtesy: https://human-memory.net/parietal-lobe/

Evaluative Echoes

Although there aren’t any particular diagnostic standards for Balint syndrome, there are several resources that can help explain symptoms. Simultagnosia symptoms can be identified by asking patients to understand difficult scenes like the “Telegraph Boy” and the “Boston Cookie Theft.” Patients can recognise specific objects in an image, but they are unable to accurately decipher the scene’s action. Ishihara colour plates, which call for adding coloured dots to create a larger number, will also be challenging for patients to understand. Patients will be able to recognise each colour on the plate accurately, therefore this is not the result of aberrant colour vision. When ruling out cerebral haemorrhage, non-contrast computed tomography (CT) of the head is typically the most effective initial test. Bilateral injury to the parietal and occipital lobes from ischemia, haemorrhage, tumour, or cortical atrophy may be shown on magnetic resonance imaging (MRI). Reduced cerebral perfusion may be shown on single-photon emission computed tomography (SPECT) scans. ⁽⁴⁾

Managing Minds

The mainstay of managing Balint syndrome is rehabilitation and minimising the degree of disability. There are various situations when secondary preventative interventions can be used to lower the chance of recurrence, such as infarction, PRES, and viral aetiologies. Various strategies have been put forth in vocational rehabilitation to assist people in reducing their incapacitating symptoms. Using the intact talents to lessen the severity of the symptoms’ impairment is known as the adaptive method. By teaching children’s perceptual abilities, the remedial approach seeks to heal the damaged brain regions. The third and most complicated method is a multi-context strategy that uses many tasks in an environment to facilitate strategic learning. ⁽⁵⁾

 

References:

1. Parvathaneni, A., & M Das, J. (2023). Balint Syndrome. In StatPearls. StatPearls Publishing.
2. Pelak, V. S. (2019). Disorders of higher cortical visual function. In Liu, Volpe, and Galetta’s Neuro-Ophthalmology (pp. 341-364). Elsevier.
3. Ghoneim, A., Pollard, C., Greene, J., & Jampana, R. (2018). Balint syndrome (chronic visual-spatial disorder) presenting without known cause. Radiology case reports, 13(6), 1242-1245.
4. Escalere, M., Joly, C., Palisson, J., Budowski, C., Mongin, M., & Degos, B. (2022). Balint’s syndrome revealing Creutzfeldt-Jakob disease. Revue neurologique, 178(3), 278–280.
5. Heutink, J., Indorf, D. L., & Cordes, C. (2019). The neuropsychological rehabilitation of visual agnosia and Balint’s syndrome. Neuropsychological rehabilitation, 29(10), 1489–1508.