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Updated: Jun 10, 2026
07:32
Analyzing Mitochondrial Transport and Morphology in Human Induced Pluripotent Stem Cell-Derived Neurons in Hereditary Spastic Paraplegia
Published on: February 9, 2020
Brow motility in mitochondrial myopathy.
Flávia Augusta Attié de Castro1, Antonio Augusto V Cruz, Cláudia Ferreira da Rosa Sobreira
1Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, School of Medicine of Ribeirão Preto, University of São Paulo, Bandeirantes, Ribeirão Preto, SP, Brasil.
Ophthalmic Plastic and Reconstructive Surgery
|August 5, 2010
Summary
Patients with chronic progressive external ophthalmoplegia (CPEO) show reduced brow excursion compared to controls. However, most patients retain sufficient brow movement for potential visual axis clearing after surgery.
Area of Science:
- Ophthalmology
- Neuromuscular Disorders
Background:
- Mitochondrial myopathy can cause chronic progressive external ophthalmoplegia (CPEO), affecting eye muscles.
- Brow excursion is a compensatory mechanism for visual field obstruction.
Purpose of the Study:
- To quantify brow excursion in patients with mitochondrial myopathy and CPEO.
- To compare brow motility in CPEO patients with healthy controls.
Main Methods:
- Digital image processing was used for quantitative analysis.
- Measurements included eyelid position, brow excursion, and eye movements.
- A comparative case series design involved 19 CPEO patients and 27 controls.
Main Results:
- CPEO patients exhibited ptosis (0.6-8 mm) and symmetrical, though limited, eye movements, predominantly affecting elevation.
- Brow motility in CPEO patients was 56.7% of that in controls.
- 76% of patients had over 2 mm of brow excursion, independent of age or eye motility.
Conclusions:
- The occipitofrontalis muscle is less affected in CPEO than extraocular muscles.
- A significant portion of CPEO patients retain useful brow excursion.
- This brow motility may be leveraged for visual rehabilitation through brow suspension surgery.
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