Automatic classification of kidney stone components based on smartphone microscopy and the GoogLeNet model

To develop an automated classification system for urinary stone composition by integrating smartphone-based microscopic imaging (TIPSCOPE) with the GoogLeNet architecture, with the goal of enabling rapid, accurate, and cost-effective analysis of stone composition.

A total of 140 surgically extracted kidney stone samples were collected and classified into four categories: calcium oxalate (66 cases), uric acid (32 cases), carbonate apatite (26 cases), and magnesium ammonium phosphate hexahydrate (16 cases). Microscopic images of the stones were acquired using the TIPSCOPE device paired with a Realme GT5 smartphone, resulting in a dataset of 840 images. The classification model was trained using the Adam optimizer, with 90% of the dataset allocated for training and 10% reserved for testing.

The overall accuracy of the system reached 85.7%. Performance metrics for each category were as follows: uric acid stones: F1 = 0.92 (precision = 0.90, recall = 0.95); magnesium ammonium phosphate hexahydrate stones: F1 = 0.95 (precision = 0.90, recall = 1.00); calcium oxalate stones: F1 = 0.86 (precision = 0.85, recall = 0.88); carbonate apatite stones: F1 = 0.69 (precision = 0.77, recall = 0.63).

This study successfully developed a kidney stone composition classification system integrating a smartphone-based microscope with a deep learning model, achieving an overall classification accuracy of 85.7%. The system exhibited strong performance in classifying uric acid and magnesium ammonium phosphate hexahydrate stones. With its low cost, efficiency, and portability, this system offers an economical and practical diagnostic solution for resource-limited regions.