Computer Vision Technology in the Differential Diagnosis of Cushing's Syndrome.

OBJECTIVE: Cushing's syndrome is a rare disease characterized by clinical features that show morphological similarity with the metabolic syndrome. Distinguishing these diseases in clinical practice is challenging. We have previously shown that computer vision technology can be a potentially useful diagnostic tool in Cushing's syndrome. In this follow-up study, we addressed the described problem by increasing the sample size and including controls matched by body mass index. METHODS: We enrolled 82 patients (22 male, 60 female) and 98 control subjects (32 male, 66 female) matched by age, gender and body-mass-index. The control group consisted of patients with initially suspected, but biochemically excluded Cushing's syndrome. Standardized frontal and profile facial digital photographs were acquired. The images were analyzed using specialized computer vision and classification software. A grid of nodes was semi-automatically placed on disease-relevant facial structures for analysis of texture and geometry. Classification accuracy was calculated using a leave-one-out cross-validation procedure with a maximum likelihood classifier. RESULTS: The overall correct classification rates were 10/22 (45.5%) for male patients and 26/32 (81.3%) for male controls, and 34/60 (56.7%) for female patients and 43/66 (65.2%) for female controls. In subgroup analyses, correct classification rates were higher for iatrogenic than for endogenous Cushing's syndrome. CONCLUSION: Regarding the advanced problem of detecting Cushing's syndrome within a study sample matched by body mass index, we found moderate classification accuracy by facial image analysis. Classification accuracy is most likely higher in a larger sample with healthy control subjects. Further studies might pursue a more advanced analysis and classification algorithm.

IGF-1-based screening reveals a low prevalence of acromegaly in patients with obstructive sleep apnea.

PURPOSE: Recent epidemiologic studies suggest a high prevalence of acromegaly. The prevalence of obstructive sleep apnea syndrome (OSAS) in acromegaly patients ranges from 47 to 70%. A recent study identified 2 patients with acromegaly among 567 OSAS patients. However, it remains unclear whether screening for acromegaly among OSAS patients is necessary. The aim was to screen for acromegaly among OSAS patients by measuring IGF-1 levels and performing confirmatory tests if necessary. METHODS: We performed a prospective cross-sectional diagnostic study on the prevalence of acromegaly in patients with OSAS. A total of 507 patients with a confirmed diagnosis of OSAS (357 male, 150 female) were screened. RESULTS: Seven male and three female patients (1.97% of total) were positively screened for elevated IGF-1 levels. Nine out of ten patients suppressed growth hormone levels during OGTT excluding acromegaly, whereas one individual was identified to have acromegaly according to established criteria (1/507, prevalence 0.2%). Analysis of the data showed no correlation between elevated IGF-1 values and the severity of OSAS or BMI. CONCLUSIONS: Our data demonstrate a low prevalence of acromegaly in patients with OSAS. Until data from population-based studies is available we suggest restricting screening for acromegaly in OSAS to those patients who have additional clinical features of acromegaly.

Body Image Perception in Acromegaly Is Not Associated with Objective Acromegalic Changes but Depends on Depressive Symptoms.

OBJECTIVE: Diagnosis of acromegaly is delayed up to 10 years after disease onset despite obvious external/objective changes such as bone and soft tissue deformities. We hypothesized that a lack of subjective perception of the disease state, possibly mediated by psychiatric or cognitive alterations, might contribute to the delayed initiation of a diagnostic workup. DESIGN: Cross-sectional study. METHODS: We investigated perceived body image by standardized questionnaires (FKB-20: Fragebogen zum Körperbild; FBeK: Fragebogen zur Beurteilung des eigenen Körpers) in 81 acromegalic patients and contrasted them to (a) a clinical control group of 60 patients with nonfunctioning pituitary adenomas (NFPA) who lack severe facial and physical alterations and (b) healthy controls. We further evaluated body image in relation to objective acromegalic changes as judged by medical experts and psychiatric pathology, e.g. depression and cognitive impairment. RESULTS: Patients with acromegaly did not lack subjective perception of the disease state; they showed more negative body image, less vitality, more insecurity/paresthesia and more accentuation of the body compared to normal controls. NFPA patients differed from acromegalic patients only in the 'vital body dynamics' scale of the FKB-20, although they hardly exhibit any physical/bodily changes. Depression correlated with worse body image. No associations were found between body image and objective acromegalic changes as judged by medical experts, cognitive decline or treatment status. CONCLUSIONS: Negative body image in acromegalic patients is unrelated to their objective appearance and similar to those of NFPA patients without major bodily changes. Depression, but not cognitive decline or treatment status, contributes to negative body image.