Page 8 - ITPS-6-2

INNOSC Theranostics and
Pharmacological Sciences Theranostics in neurosurgery

separate therapeutic and diagnostic modalities to achieve emerged in its ability to disrupt the blood–brain barrier
theranostic capabilities. (BBB) , which is a dynamic membrane that encapsulates
[10]
First, theranostics can be a modality that combines various cells, proteins, and molecules to protect the
diagnostic and therapeutic capabilities within the same brain from harmful substances. The permeability of the
medium. Delivering treatment while the patient’s condition BBB is maintained by tight endothelial junctions created
is being evaluated has countless implications for improving between neuroendothelial cells, pericytes, microglia,
[11]
the accessibility and cost-effectiveness of neurosurgical and astrocytes . These cells have different functions.
procedures. If treatment and diagnosis can be completed For instance, microglia play a role in immune response,
[10]
at the same time, fewer hospital visits and less overall while astrocytes contribute to the structure of the BBB .
technology would be required to provide care, reducing the Contrastingly, the blood tumor barrier (BTB) that forms in
need for multiple treatment regimens, which can improve the brain manipulates this barrier to become more “leaky”
[11]
patient adherence over time. One such example is focused and permeable . The BTB, however, is not leaky enough to
ultrasound (FUS), which has therapeutic effects, such as promote enhanced permeability of various chemotherapy
neuroablation, while simultaneously existing as a useful molecules or other therapeutic drugs. FUS is utilized for
diagnostic tool . In addition, using radiopharmaceuticals its ability to disrupt the BBB and temporarily create gaps
[4]
for molecular imaging can treat neurological disorders to allow various therapeutic agents to transfuse and cross
while they are being diagnosed . In both procedures, the through the membrane.
[5]
diagnostic medium can also be used for the treatment of a FUS can improve the administration of specific
condition. Second, theranostics can combine a diagnostic chemotherapeutic agents by increasing the permeability
tool with a separate therapeutic modality. This approach of BTBs. For instance, drugs such as doxorubicin have
to theranostics strives to collect diagnostic biofeedback displayed significant improvements in tumors in vitro,
during therapy to improve the evaluation of clinical but they cannot cross the BTB . Research on FUS in
[10]
outcomes and the management of treatment toxicities. For disrupting the BTB was previously restricted by the
instance, automated pathology analysis and intraoperative fear of permanent tissue damage, but FUS is now being
consultation (IOC) enhance the surgical resection process increasingly studied for this ability. The interaction of
for brain tumors . In addition, diagnostic tools for cerebral FUS with tissue is frequency-dependent. FUS with lower
[6]
palsy (CP) can be used to inform electrical stimulation frequencies provides a greater level of penetration but
therapies to improve their accuracy and precision . with a lower resolution. Higher frequencies achieve the
[7]
In these approaches, diagnostic techniques are used to opposite effect, with higher resolution and lower levels
enhance the treatment process. of penetration . To protect the extraneous healthy
[12]
Theranostics has many clear advantages, including the soft tissue, lower frequencies with penetration depths
[13]
improved prediction of toxicities and a real-time evaluation restricted to 1 cm are used . Further, a study by Hynynen
of patient responses, as discussed through the various et al. showed that when specific low frequencies of FUS
[14]
technologies used . One limitation of theranostics is the are used, permanent cranial damage can be minimized .
[3]
relatively recent development of theranostic tools, which One method for administering the low frequencies is
leads to a highly variable sensitivity and specificity and through the use of microbubbles that span from 1 to 5 µm
[10]
results in the unintended exclusion of patients who would in diameter . These bubbles contain lipid-enveloped gas
have otherwise benefited from these technologies. In recent molecules that are administered episodically, and dosage
years, theranostics research has focused on oncology and delivery to the BBB can be monitored and modified as
immunology . The current review will further investigate necessary [15,16] . The various oscillations and concentrations
[8]
its applicability in neurosurgery through FUS, molecular of the microbubbles have the potential to create mechanical
imaging using radiopharmaceuticals, automated pathology forces to open the BBB [10,13] .
analysis of brain tumors, and electrical stimulation in CP. One team led by Liu et al. monitored the effectiveness
of FUS in delivering therapeutic agents to the brain
2. FUS using magnetic resonance imaging (MRI) . Their
[17]
FUS in neurosurgery has transformed the treatment studies indicated that FUS can help provide an enhanced
procedures available for various neurological diseases. image monitoring system and dramatically increase the
This technology focuses beams of energy on a single delivery of epirubicin, among other chemotherapeutic
location to provide critical diagnostic and therapeutic care agents . Another study analyzed pembrolizumab, which
[17]
without harming the surrounding tissue . Research has is a commonly used chemotherapy drug that targets the
[9]
shown that a promising benefit from this technology has immune system and prevents specific T-cells from being

Volume 6 Issue 2 (2023) 2 https://doi.org/10.36922/itps.417