title: Intracellular extraocular muscle light- and heavy-chain deposition disease contributing to compressive optic neuropathy in a patient with preexisting Graves' orbitopathy.
abstract: OBJECTIVE
  Light- and heavy-chain deposition disease (LHCDD) is a rare form of nonamyloidal monoclonal immunoglobulin deposition disease (MIDD) in which light- and heavy-chain immunoglobulin fragments accumulate systemically, typically leading to end organ dysfunction. Herein we describe the case of a 64-year-old female with a history of Graves' orbitopathy and multiple myeloma who presented with bilateral asymmetric compressive optic neuropathies.
  
  
  METHODS
  A biopsy of the right medial rectus muscle was taken during orbital decompression surgery.
  
  
  RESULTS
  Light and electron microscopy of the biopsy specimen led to a diagnosis of intracellular skeletal muscle LHCDD.
  
  
  CONCLUSIONS
  This is the first published report to describe the findings of: (1) intracellular deposition of nonamyloidal MIDD; (2) orbital involvement of nonamyloidal MIDD, and (3) compressive optic neuropathy resulting from any form of MIDD.
authors.affiliation: Department of Ophthalmology, University of British Columbia, Vancouver, BC, Canada. pz@interchange.ubc.ca
authors.forename: Peter A
authors.initials: PA
authors.lastname: Zakrzewski
authors.forename: Ezekiel
authors.initials: E
authors.lastname: Weis
authors.forename: Valerie A
authors.initials: VA
authors.lastname: White
authors.forename: Jack
authors.initials: J
authors.lastname: Rootman
mesh_terms: D001706:Biopsy; D019299:Decompression, Surgical; D005260:Female; D006111:Graves Disease / Q000150:complications* / Q000473:pathology / Q000601:surgery; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000378:metabolism*; D007147:Immunoglobulin Light Chains / Q000378:metabolism*; D008875:Middle Aged; D009101:Multiple Myeloma / Q000150:complications* / Q000473:pathology / Q000601:surgery; D009801:Oculomotor Muscles / Q000473:pathology* / Q000601:surgery; D010265:Paraproteinemias / Q000150:complications* / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed; D014792:Visual Acuity
chemical_list: D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains