ABSTRACT
This study examined whether pathological findings were present in cochlear vessels for patients with diabetes mellitus. Twenty-six temporal bones from 13 patients with type 1 diabetes mellitus and 40 temporal bones from 20 patients with type 2 diabetes mellitus were examined. Type 2 diabetic temporal bones were divided into 2 groups according to diabetic management (22 temporal bones with insulin therapy, and 18 with oral hypoglycemic drugs). Age-matched normal control temporal bones were also selected. The vessel wall thickness in the cochlear spiral modiolar artery was measured under a light microscope, and the vessel wall ratio (vessel wall thickness/outer diameter of the vessel x 100) was calculated. The vessel wall thickness and vessel wall ratio in type 1 diabetes mellitus were significantly greater than in normal controls. Type 2 diabetic patients with insulin therapy showed significantly greater vessel wall thickness and vessel wall ratios than controls. In type 2 diabetes mellitus, the vessel wall thickness and vessel wall ratio were greater in patients treated with insulin therapy than in those treated with oral hypoglycemic agents. Type 2 diabetic patients with insulin therapy showed an increased vessel wall thickness and vessel wall ratio compared to patients with type 1 diabetes mellitus. In conclusion, the cochlea in patients with diabetes mellitus shows circulatory disturbance compared to age-matched normal controls.
Subject(s)
Cochlea/blood supply , Diabetes Mellitus, Type 1/pathology , Diabetes Mellitus, Type 2/pathology , Temporal Bone/pathology , Adolescent , Adult , Aged , Arteries/pathology , Case-Control Studies , Child , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Female , Humans , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Male , Middle Aged , Young AdultABSTRACT
PURPOSE OF REVIEW: The aim of this study is to summarize current advances in research and clinical aspects of cochlear otosclerosis. RECENT FINDINGS: Recent studies have revealed that otosclerosis is a process of bone remodeling that is unique to the otic capsule only. Even though no obvious bone remodeling is seen in the otic capsule under normal conditions, remodeling starts when some molecular factors trigger the capsule in certain patients who have genetic and/or environmental tendencies. SUMMARY: Cochlear otosclerosis is defined as otosclerosis located in the otic capsule involving the cochlear endosteum and causing sensorineural hearing loss or mixed-type hearing loss. It has been clearly shown that, when otosclerosis is sufficiently severe to involve the cochlear endosteum, it usually fixes the stapes as well.