Registration Accuracy of Patient-Specific, Three-Dimensional-Printed Prostate Molds for Correlating Pathology With...

Area of Science:

• Medical Imaging
• Pathology
• Biomedical Engineering

Background:

• Accurate registration between magnetic resonance imaging (MRI) and histopathology is crucial for correlating in vivo imaging with tissue analysis.
• Traditional manual slicing methods can introduce significant errors in specimen alignment.
• Three-dimensional (3-D) printing offers a potential solution for creating patient-specific molds to improve specimen handling and registration.

Purpose of the Study:

• To evaluate the registration accuracy between MRI and pathology using 3-D-printed molds.
• To compare the accuracy of manual slicing versus mold-assisted slicing of tissue phantoms.
• To assess the utility of 3-D-printed molds for radical prostatectomy specimens.

Main Methods:

• Tissue-mimicking prostate phantoms with fiducials were used to compare manual versus mold-assisted slicing.
• Ten radical prostatectomy specimens were scanned with MRI, placed in 3-D-printed molds, and then sliced.
• Target registration error (TRE) and angular misalignment were measured using anatomic landmarks and ex vivo MRI.

Main Results:

• Mold-assisted slicing reduced mean TRE from 4.1 mm to 1.9 mm in phantoms.
• Angular misalignment around the left-right axis decreased from 10.7° to 4.5° with molds.
• Ex vivo MRI revealed specimen misalignment within molds, but registration accuracy improved to 2.2 mm TRE after correction.

Conclusions:

• Patient-specific 3-D-printed molds enhance MRI-pathology registration accuracy compared to manual techniques in phantom models.
• Imperfect specimen fit within molds can limit registration accuracy for surgical specimens.
• Integrating ex vivo imaging with 3-D-printed molds overcomes limitations and improves overall registration precision.