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Related Experiment Video

Updated: Jun 19, 2026

High-throughput Identification of Synergistic Drug Combinations by the Overlap2 Method

High-throughput Identification of Synergistic Drug Combinations by the Overlap² Method

Published on: May 21, 2018

Variable synergistic divergence.

Jae Hyoung Kim¹, Jeong-Min Hwang

¹Department of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.

Optometry and Vision Science : Official Publication of the American Academy of Optometry

|October 15, 2009

Summary

This summary is machine-generated.

Congenital fibrosis of the extraocular muscles can manifest as synergistic divergence or adduction, a previously undocumented presentation. This case highlights the varied clinical expressions of this rare neuromuscular disorder.

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Area of Science:

Ophthalmology
Neurology
Genetics

Background:

Congenital fibrosis of the extraocular muscles (CFEOM) is a rare neuromuscular disorder characterized by limited eye movements.
It is typically associated with specific genetic mutations affecting cranial nerve development.
Previous reports have described various patterns of eye muscle dysfunction.

Observation:

A 7-year-old girl presented with congenital fibrosis of the extraocular muscles and abnormal eye movements since childhood.
Ophthalmologic examination revealed exotropia, limited upgaze and downgaze, and poor levator function.
Brainstem MRI showed absence of the left abducens nerve and severe hypoplasia of the oculomotor nerves.

Findings:

The patient exhibited synergistic divergence in attempted right gaze and variable adduction or abduction in attempted left gaze.
Medial and superior recti muscles were atrophic.
This presentation of alternating synergistic divergence or adduction is novel in CFEOM.

Implications:

This case expands the known spectrum of clinical manifestations in congenital fibrosis of the extraocular muscles.
Understanding these varied presentations is crucial for accurate diagnosis and management.
Further research into the genetic and developmental underpinnings of CFEOM is warranted.