Description
Clinical History
Over a 3-year period, a 57-year-old woman had intermittent frontal headache and memory disturbance with progression to psychiatric disturbance, and ultimately vomiting and meningeal signs. Localizing neurological signs only developed late in the course of the disease.
Pathology
Coronal section through the cerebral hemisphere demonstrates a round, hemorrhagic, variegated tumor in the left temporal lobe. Less well-defined tumor tissue extends across the mid-line replacing the corpus callosum. The ventricular system has been almost totally obliterated. Further sections through the cerebral hemisphere confirmed that these apparently separate lesions are extensions of one massive tumor.
Further Information
Gliomas are the second most common cancer of the central nervous system after meningiomas. The term glioma refers to tumors that are histologically similar to normal glial (macroglial) cells* i.e. astrocytes, oligodendrocytes and ependymal cells. They arise from a progenitor cell that differentiates down one of the cell lines. GBMs can arise in the brain de novo or evolve from lower-grade astrocytomas or oligodendrogliomas. GBM is often referred to as a grade IV astrocytoma. They are differentiated histologically from anaplastic astrocytomas by necrotizing tissue surrounded by anaplastic cells as well as by the presence of hyperplastic blood vessels.
GBMs are more common in males. It is most commonly diagnosed in the 6th decade of life. Genetic risk factors include neurofibromatosis type 1 and Li-Fraumeni syndrome. Previous brain radiotherapy is also associated with increased risk of GBM. Symptoms vary depending on the location of the GBM, but may include any of the following:
- Persistent headaches
- Double or blurred vision
- Vomiting
- Loss of appetite
- Changes in mood and personality
- Changes in ability to think and learn
- New onset of seizures
- Speech difficulty of gradual onset
Diagnostic tools include computed tomography (CT scan) and magnetic resonance imaging (MRI). Around 50% of these tumors occupy more than one cerebral hemisphere. GBMs commonly extend into the ventricular walls or meninges, and thus into the central spinal fluid (CSF). Spinal cord spread is uncommon. Metastasis beyond the central nervous system is rare. Tumor growth causes cerebral oedema leading to increased intra-cranial pressure. These are biologically aggressive tumors, and if left untreated survival is typically 3 months. The mainstay of treatment for GBMs is surgery, followed by radiation and chemotherapy.
*Microglia are a different lineage from macroglia. The former are related to the macrophage lineage, and arise initially from the yolk sac and later in development from the bone marrow.
Advantages
- Anatomically accurate and identical to real specimen
- No ethical issues - not real human body parts
- Reasonably priced
- Available within a short lead time
- Reproducible, several identical prints can be used as a classroom set
- Can be produced in different sizes to cater for the needs of the teacher
Human Cadavers
- Access to cadavers can be problematic. Many countries cannot access cadavers for cultural and religious reasons
- Cadavers cost a lot money
- High cost for establishing your own plastination suite
- Wet specimens cannot be used in uncertified labs
- Dissection of cadavers is a lot of staff time and that is a cost
- Storage of cadaver material needs special refrigeration etc. which has coast
- If you want another specimen you have to start all over again
Plastinates
- Costs
- Ethical issues
- Timeframe for plastination process
- Many countries do not allow their importation
- One of a kind
Superior 3D print results compared with conventional methods
- Vibrant color offering with 10 million colors
- UV-curable inkjet printing
- High quality 3D printing that can create products that are delicate, extremely precise and incredibly realistic
Clear Support Material
- To avoid breakage of fragile, thin, and delicate arteries, veins or vessels, a clear support material is printed on such spots. This makes the models robust and can be handled by students easily.
