Abdominal Wall Hernia: Diagnostic Framework Pre-op Biometrics & Post-op Pathology Engine

v4

AWR Diagnostic Framework

Pre-op Biometrics & Post-op Pathology Engine

Framework By

Dr. Sharad Maheshwari, MD

Preoperative AWR Biometrics

Calculate Loss of Domain, Component Separation Index, and Tissue Quality.

📖 Read the Blog: LOD & Tanaka

1. Volumetric Data (Ellipsoid Formula: 0.52 × L × W × D)

Hernia Sac Dimensions (cm)

Length (CC)

Width (TRV)

Depth (AP)

Abdominal Cavity Dimensions (cm)

Length (CC)

Width (TRV)

Depth (AP)

2. Defect Morphology & Tissue Quality

Transverse Defect Width

cm

Angle of Diastasis (CSI)

°

Avg. Rectus Width

cm

Avg. Rectus Thickness

cm

Subcutaneous Fat Thickness (Linea Alba)

cm

⚙ Algorithmic Outputs

Tanaka Index

--%

Awaiting data. > 25% signifies significant Loss of Domain.

Component Sep. Index

--

Awaiting data. > 0.21 limits primary fascial closure.

Rectus:Defect Ratio

--

Awaiting data. < 2.0 suggests need for Component Separation.

Tissue Quality Warnings

Sarcopenia (Muscle Atrophy) ✔ Checked

SSO/SSI Risk (Subcut Fat) ✔ Checked

Post-Operative Logic Engine

Rule-based classification of post-surgical findings.

Classify + Grade + Act Protocol

Select Imaging Findings

Fluid Collection Present

Thick / Enhancing Rim Internal Gas / Air Bubbles Hyperdense (>30 HU)

Contrast Extravasation

Fascial Defect (Hernia)

Non-enhancing Bowel Content (Ischemia) Transition Point (Obstruction)

Generated DECOMP Report

Post-Op Imaging & Anatomy

Understanding surgical planes and temporal complication curves.

📖 Read the Blog: Post-Op Imaging

Modern Mesh Planes (Lateral to Medial)

Superficial

Onlay Repair

Mesh placed anterior to the anterior rectus sheath. Requires massive subcutaneous dissection.
Risk: Highest rate of seromas and SSI.

Intramuscular / Gold Standard

Retrorectus (Sublay / Rives-Stoppa)

Mesh placed between the rectus muscle and posterior rectus sheath. Highly vascularized.

Deep / Preperitoneal

eTEP / TAR

Mesh placed extraperitoneally. Peritoneum is kept intact. Fluid collections here are deep and separated from bowel.

Clinical Pearls & Pitfalls

• ❌
  Air always equals a leak. Truth Post-operative pneumoperitoneum is expected up to 7-14 days. Worry if it increases or clusters near an anastomosis.
• ❌
  Fluid collection means abscess. Truth Seromas are expected body responses to dissection (especially Onlay). Look for rim enhancement, air, or clinical sepsis markers before calling an abscess.
• ❌
  Richter's hernia requires obstruction. Truth Because only the antimesenteric wall is pinched, the bowel lumen remains open. These often present with ischemia/perforation WITHOUT systemic obstruction.

i Title