Fully Automated Measurement of the Insall-Salvati Ratio with Artificial Intelligence.

Patella alta (PA) and patella baja (PB) affect 1-2% of the world population, but are often underreported, leading to potential complications like osteoarthritis. The Insall-Salvati ratio (ISR) is commonly used to diagnose patellar height abnormalities. Artificial intelligence (AI) keypoint models show promising accuracy in measuring and detecting these abnormalities.An AI keypoint model is developed and validated to study the Insall-Salvati ratio on a random population sample of lateral knee radiographs. A keypoint model was trained and internally validated with 689 lateral knee radiographs from five sites in a multi-hospital urban healthcare system after IRB approval. A total of 116 lateral knee radiographs from a sixth site were used for external validation. Distance error (mm), Pearson correlation, and Bland-Altman plots were used to evaluate model performance. On a random sample of 2647 different lateral knee radiographs, mean and standard deviation were used to calculate the normal distribution of ISR. A keypoint detection model had mean distance error of 2.57 ± 2.44 mm on internal validation data and 2.73 ± 2.86 mm on external validation data. Pearson correlation between labeled and predicted Insall-Salvati ratios was 0.82 [95% CI 0.76-0.86] on internal validation and 0.75 [0.66-0.82] on external validation. For the population sample of 2647 patients, there was mean ISR of 1.11 ± 0.21. Patellar height abnormalities were underreported in radiology reports from the population sample. AI keypoint models consistently measure ISR on knee radiographs. Future models can enable radiologists to study musculoskeletal measurements on larger population samples and enhance our understanding of normal and abnormal ranges.

Use of the polymerase chain reaction in the diagnosis of ocular disease.

The polymerase chain reaction is a recently introduced laboratory technique that allows for the identification of extremely small quantities of DNA. This technique offers significant advantages over more traditional methods of identifying infectious organisms causing ocular pathology. Increasing numbers of immunosuppressed and immunocompromised patients have led to the emergence of posterior segment infection from unusual and sometimes difficult to diagnose organisms. Improvements in antibiotic and antiviral therapy for specific organisms will require increasingly accurate diagnosis. Polymerase chain reaction is capable of providing this and is increasingly being used in the diagnosis of unusual vitreoretinal pathology.

Corticosteroid-induced avascular necrosis of the talus.

An unusual case of avascular necrosis of the talus secondary to chronic steroid usage is presented, along with a review of the literature. Etiologic factors as well as radiographic and clinical features will be discussed. Possible treatment alternatives will be reviewed. With greater knowledge of this pathologic process, prompt diagnosis may prevent its potentially harmful sequelae.