Surgical planning tool for intervention in patients with facial lipodystrophy

Scope

The acquired immunodeficiency syndrome (HIV) has become a chronic disease in recent years thanks to the development of powerful new drugs, allowing patients to develop an almost normal life. However, one of the side effects of treatments for AIDS is the marked lipodystrophy that occurs in some parts of the body. Lipodystrophy is a pathological condition characterized by focal or general lack of adipose tissue. Using various injectable materials surgeons reestablish these surfaces in the patient to acquire a normal physical appearance.

A surgical planning tool that provides the patient’s facial models along with measures of volume to fill has been developed. The tool has been implemented using VTK (visualization toolkit), which is an open-source, freely available software system for 3D computer graphics, image processing and visualization. VTK consists of a C++ class library and several interpreted interface layers including Tcl/Tk, Java, and Python.

The main steps of the algorithm implemented are as follows:

  1. Load the surface model of the patient in the programming environment VTK
  2. User intervention is required for the selection of points around the surface to intervene.
  3. The algorithm calculates and proposes a central point (centroid) which is used to compute the new interpolated surface. This centroid can be modified by the surgeon as desired.
  4. From the centroid, lines are drawn at all points of the outer curve. New points are created equally spaced along these lines. To give regularity to the surface the Delaunay triangulation algorithm and a Gaussian smoothing are applied.
  5. The program calculates the volume difference between the new interpolated surface and the original surface in the patient’s facial model.

Collaborations

Fundación Pública Andaluza para la Gestión de la Investigación en Salud de Sevilla (FISEVI)

Hospitales Universitarios Virgen del Rocío

Funding

Virtual reality applied Reconstructive Treatments for Facial Lipodystrophy Syndrome, Fundación para la Investigación y la Prevención del Sida en España (FIPSE)

Images


Publications

  • Conference ProceedingsJ.A. Pérez-Carrasco, C. Serrano, B. Acha, T. Gómez-Cía, “Herramienta de planificación quirúrgica para la intervención de pacientes con lipodistrofia facial”, XXIX Congreso Anual de la Sociedad Española de Ingeniería Biomédica (CASEIB2011), Cáceres, España, 2011.