Menelik: A detailed human head computational model
I have developed a detailed human head model named "Menelik", in both voxel and triangular surface mesh formats, based on the Visible Human Project (VHP) male image data set. The model has 33 different anatomical structures that were indexed to 23 voxel regions based on their electromagnetic material properties. The model was validated and tested by simulating a scenario of transcranial Direct Current Stimulation (tDCS) and by computing the specific absorption rate (SAR) from a transmit coil of magnetic resonance imaging (MRI).
At the time of this entry (June 2018), Menelik is the only detailed human body model that is available in both voxel and mesh formats, tested for finite element method (FEM) meshability, and freely distributed.
All the Menelik model data can be accessed freely from our Figshare project. The project data collection contains:
- Menelik head mesh format (ACIS SAT v.26)
- Menelik head mesh model (STL files).
- Menelik head voxel model (with CST Studio and SEMCAD X header files)
- Menelik head voxel model (in NIFTI format)
- Menelik head voxel model (DES file format)
- Menelik head voxel model (DICOM (MR) format)
A more detailed head and shoulder model version in SAB format can be dowloaded here:
Find out more about Menelik Head Model.
Menelik Whole: A detailed human body computational model
I have developed a detailed computational model of the human whole body (Menelik Whole). The model has been tested for electromagentic simulation with hexahedral meshing in CST Studio - for plane wave exposure.
You can download the SAB format here:
Computational model of a pregnant female
I have developed a computational human body phantom (surface triangular mesh) of a 30 weeks pregnant female. The developed model is anatomically realistic and complete compared to other models; and it has 32 different types of anatomical structures.
The model was developed by combining the 3D CAD model of a non-pregnant female and a foetus - with the aid of a pregnant female’s anatomical atlas. The non-pregnant female model was constructed by NEVA Electromagnetics from the open source cryosection image dataset of a female cadaver available from the Visible Human Project of the U. S. National Library of Medicine. The foetus model was obtained from Télécom ParisTech, France.
Safety Analysis of Electroconvulsive Therapy (ECT) during pregnancy
I have used the pregnant female computational phantom model to assess the safety of electroconvulsive therapy (ECT) on pregnant patients, which had not been addressed before. The results suggest that, considering the maximum current output, pulse width, and frequency range of constant-current ECT devices, the electric field produced inside the foetal brain is most likely below the basic restriction set by the International Commission for Non-Ionising Radiation Protection (ICNIRP) . This is based on the practical scenario of a 30-weeks foetus with a bottom-up and head-down foetal position and the mother taller than 1.62 m.
- Electroconvulsive therapy (ECT) during pregnancy: quantifying and assessing the electric field strength inside the foetal brain, https://rdcu.be/13vH Scientific Reports (Nature), 2018
Safety Analysis of Transcutaneous Electrical Nerve Stimulation (TENS) during pregnancy
Transcutaneous electrical nerve stimulation (TENS) is considered one of the safest options of pain management for lower back pain during pregnancy and labour. For lower back management, the TENS electrodes are attached at the lower back and deliver pulsed electric current of peak 80 mA. TENS is self-administered; and the device is sold without prescription. However, there is no study that assess the safety of the electric field generated from TENS device on the foetus. For the first time, I computed and assessed the safety of the electric field on the foetus. I found that its magnitude is large enough that it might stimulate the central nervous system of the foetus. The results are being prepared as a journal article. (You can access the draft article).
An improved nonlinear cable equation for a dynamic computation of deep brain stimulation (DBS)
With the objective of improving the general nonlinear cable equation, which is used to model the electrical activation of myelinated or unmyelinated axons, I included axon scattered fields in the nonlinear cable equation by utilizing the techniques in wire antenna analysis. By adopting the well-established techniques in wire antenna analysis, I reduced the complexity and time required to model the activation of realistic neuron populations. I am working to apply this model in the simulation of DBS and use the result to derive an expression for the volume of activated tissue (VAT) as function of easily controlled input values, such as, electrode voltage amplitude and frequency.
