Infrared Thermography in Surgery of Newly Diagnosed Glioblastoma Multiforme: A Technical Case Report

Barbed tonsillectomy

PURPOSE

Although tonsillectomy is a common otolaryngological procedure renowned for its ease and safety, it is associated with various complications such as hemorrhage, dysphagia, pain, and infection. Post-tonsillectomy bleeding, especially secondary bleeding, poses a significant risk, with mortality rates reported as 5% of cases. Various techniques have been proposed to mitigate these risks, including the closure of the tonsillar fossa to prevent hemorrhage. Suturing of tonsil pillars has been suggested to enhance healing by reducing exposed surfaces. However, complications such as arterial injury and infection have been reported. This study aimed to investigate the efficacy of barbed sutures for reducing post-tonsillectomy complications compared to standard techniques.

METHODS

This prospective case-control study included 25 patients to receive a tonsillectomy with silk sutures (n = 11) or a tonsillectomy with barbed sutures (n = 14). Patients underwent either Barbed Tonsillectomy (BT) or standard tonsillectomy with external silk sutures. Pain scores were assessed using a visual analogue scale (VAS), while oropharyngeal dysphagia was evaluated using the Eating Assessment Tool (EAT-10) at two weeks and one month post-operation.

RESULTS

BT showed significantly lower postoperative pain scores than standard tonsillectomy at 24 hours (VAS: 2.9 vs. 7.0) and after two weeks (VAS: 0.1 vs. 3.4). Similarly, BT demonstrated lower EAT-10 scores at two weeks (0.6 vs. 8.2) and one month (0.9 vs. 5.3), thus indicating reduced dysphagia. Only one patient in the control group required surgical revision due to bleeding, and none in the BT group. Comparison of all variables showed always a statistically significant (p<0.05).

CONCLUSIONS

This study showed that barbed sutures in tonsillectomy may be a safe technique with reduced complications and a faster recovery. Initial findings regarding hemorrhage, pain management, and recovery outcomes are highly promising, warranting further investigation with larger sample sizes to endorse these results.

A prospective study on the usefulness of high-resolution intraoperative infrared thermography in intracranial tumors

Introduction

Infrared thermography (IT) is a non-invasive real-time imaging technique with potential application in different areas of neurosurgery. Despite technological advances in the field, intraoperative IT (IIT) has been an underestimated tool with scarce reports on its usefulness during intracranial tumor resection. We aimed to evaluate the usefulness of high-resolution IIT with static and dynamic thermographic maps for transdural lesion localization, and diagnosis, to assess the extent of resection, and the occurrence of perioperative acute ischemia.

Methods

In a prospective study, 15 patients affected by intracranial tumors (six gliomas, four meningiomas, and five brain metastases) were examined with a high-resolution thermographic camera after craniotomy, after dural opening, and at the end of tumor resection.

Results

Tumors were transdurally located with 93.3% sensitivity and 100% specificity (p < 0.00001), as well as cortical arteries and veins. Gliomas were consistently hypothermic, while metastases and meningiomas exhibited highly variable thermographic maps on static (p = 0.055) and dynamic (p = 0.015) imaging. Residual tumors revealed non-specific static but characteristic dynamic thermographic maps. Ischemic injuries were significantly hypothermic (p < 0.001).

Conclusions

High-resolution IIT is a non-invasive alternative intraoperative imaging method for lesion localization, diagnosis, assessing the extent of tumor resection, and identifying acute ischemia changes with static and dynamic thermographic maps.

Thermosensitive/thermochromic silicone and infrared thermography mapping in 60 consecutive cases of epilepsy surgery

Background

Epilepsy surgery represents a therapeutic opportunity for those patients who do not respond to drug therapy. However, an important challenge is the precise identification of the epileptogenic area during surgery. Since it can be hard to delineate, it makes it necessary to use auxiliary tools as a guide during the surgical procedure. Electrocorticography (ECoG), despite having shown favorable results in terms of reducing post-surgical seizures, have certain limitations. Brain mapping using infrared thermography mapping and a new thermosensitive/thermochromic silicone (TTS) in epilepsy surgery has introduced a new resource of noninvasive and real-time devices that allow the localization of irritative zones.

Methods

Sixty consecutive patients with drug-resistant epilepsy with surgical indications who decided to participate voluntarily in the study were included in the study. We measured brain temperature using two quantitative methods and a qualitative method: the TTS sheet. In all cases, we used ECoG as the gold standard to identify irritative areas, and all brain tissue samples obtained were sent to pathology for diagnosis.

Results

In the subgroup in which the ECoG detected irritative areas (n = 51), adding the results in which there was a correlation with the different methods, the efficiency obtained to detect irritative areas is 94.11% (n = 48/51, P ≤ 0.0001) while the infrared thermography mapping method independently has an efficiency of 91.66% (P ≤ 0.0001). The TTS has a sensitivity of 95.71% and a specificity of 97.9% (P ≤ 0.0001) to detect hypothermic areas that correlate with the irritative zones detected by ECoG. No postoperative infections or wound dehiscence were documented, so the different methodologies used do not represent an additional risk for the surgical proceedings.

Conclusion

We consider that the infrared thermography mapping using high-resolution infrared thermography cameras and the TTS are both accurate and safe methods to identify irritative areas in epilepsy surgeries.

Glioblastoma management in low and middle-income countries; existing challenges and policy recommendations

Glioblastomas (GBM) are the most prevalent malignant CNS tumors globally, affecting about 3.19 per 100,000 people. The standard of care of GBM management includes surgical resection followed by radiotherapy and/or chemotherapy owing to the high recurrent rates. Despite the advances in neurosurgical practice and brain cancer research, low- and middle-income countries (LMICs) did not benefit greatly from these advances compared to high-income countries (HICs). First, the case ascertainment is low in LMICs, which contributes to a lower than actual disease burden and delayed presentation of the tumors with a worse prognosis. Second, GBM treatment is expensive; unregulated radiation and chemotherapy costs can expose the patients to financial hardships and lead to treatment discontinuation. Third, the lack of trained neurosurgical workforce in poor resource settings in LMICs further complicates the situation. Fourth, radiation therapy and chemotherapies are expensive and unavailable in many poor-resource settings in LMICs. Fifth, LMICs suffer from a weak infrastructure especially with low numbers of prepared ORs, laboratories, and advanced imaging techniques. In the present article, we highlight the major challenges of GBM management and further propose solutions for governments and health policy makers to improve GBM care in LMICs.

Localization of irritative zones in epilepsy with thermochromic silicone

Background:

During epilepsy surgery, the gold standard to identify irritative zones (IZ) is electrocorticography (ECoG); however, new techniques are being developed to detect IZ in epilepsy surgery and in neurosurgery in general, such as infrared thermography mapping (ITM), and the use of thermosensitive/thermochromic materials.

Methods:

In a cohort study of consecutive patients with focal drug-resistant epilepsy of the temporal lobe treated with surgery, we evaluated possible adverse effects to the transient placement of a thermochromic/thermosensitive silicone (TTS) on the cerebral cortex and their postoperative evolution. Furthermore, we compared the precision of TTS for detecting cortical IZ against the gold standard ECoG and with ITM, as proof of concept.

Results:

We included 10 consecutive patients, 6 women (60%) and 4 men (40%). Age ranges from 15 to 56 years, mean 33.2 years. All were treated with unilateral temporal functional lobectomy. The mean hospital stay was 4 days. There were no immediate or late complications associated with the use of any of the modalities described. In the 10 patients, we obtained consistency in locating the IZ with ECoG, ITM, and the TTS.

Conclusion:

The TTS demonstrated biosecurity in this series. The accuracy of the TTS to locate IZ was similar to that of ECoG and ITM in this study. More extensive studies are required to determine its sensitivity and specificity.

Long-Wave Infrared Imaging for Intraoperative Cancer Detection-What is the True Temperature of a Cancer?

BACKGROUND

During cancer operations, the cancer itself is often hard to delineate-buried beneath healthy tissue and lacking discernable differences from the surrounding healthy organ. Long-wave infrared, or thermal, imaging poses a unique solution to this problem, allowing for the real-time label-free visualization of temperature deviations within the depth of tissues. The current study evaluated this technology for intraoperative cancer detection.

METHODS

In this diagnostic study, patients with gastrointestinal, hepatobiliary, and renal cancers underwent long-wave infrared imaging of the malignancy during routine operations.

RESULTS

It was found that 74% were clearly identifiable as hypothermic anomalies. The average temperature difference was 2.4°C (range 0.7 to 5.0) relative to the surrounding tissue. Cancers as deep as 3.3 cm from the surgical surface were visualized. Yet, 79% of the images had clinically relevant false positive signals [median 3 per image (range 0 to 10)] establishing an accuracy of 47%. Analysis suggests that the degree of temperature difference was primarily determined by features within the cancer and not peritumoral changes in the surrounding tissue.

CONCLUSION

These findings provide important information on the unexpected hypothermal properties of intra-abdominal cancers, directions for future use of intraoperative long-wave infrared imaging, and new knowledge about the in vivo thermal energy expenditure of cancers and peritumoral tissue.

Infrared thermography mapping plus neuronavigation target location in an eloquent area cavernoma resection

Background

Safety and efficacy are irrebuttable goals in neurosurgery.

Methods

We performed a subcortical cavernoma resection in an eloquent area, where we recorded and compared the maximal and minimal brain temperature measured by an infrared thermographic camera and thermometer with the neuronavigation (NN) target location and real anatomical lesion location.

Results

The hottest cortical point correlated to the subcortical cavernoma location. The NN located the target at 10 mm away from the hottest point.

Conclusion

More studies are needed to better understand the thermic radiation of the brain in health and in disease, but we believe that evaluating brain temperature, it could be possible to improve accuracy in neurosurgery and generate more knowledge about brain metabolism in vivo.

Thermography mapping patterns in temporal lobe epilepsy surgery

Background:

In several epilepsy etiologies, the macroscopic appearance of the epileptogenic tissue is identical to the normal, which makes it hard to balance between how much cytoreduction or disconnection and brain tissue preservation must be done. A strategy to tackle this situation is by evaluating brain metabolism during surgery using infrared thermography mapping (IrTM).

Methods:

In 12 epilepsy surgery cases that involved the temporal lobe, we correlated the IrTM, electrocorticography, and neuropathology results.

Results:

Irritative zones (IZ) had a lower temperature in comparison to the surrounding cortex with normal electric activity (difference in temperature (ΔT) from 1.2 to 7.1, mean 3.40°C standard deviation ± 1.61). The coldest zones correlated exactly with IZ in 9/10 cortical dysplasia (CD) cases. In case 3, the coldest area was at 1 cm away from the IZ. In 10/10 dysplasia cases (cases 1–4, 6–11), there was a radial heating pattern originating from the coldest cortical point. In 2/2 neoplasia cases, the temporal lobe cortical temperature was more homogeneous than in the CD cases, with no radial heating pattern, and there were no IZ detected. In case 8, we found the coldest IrTM recording in the hippocampus, which correlated to the maximal irritative activity recorded by strip electrodes. The ΔT is inversely proportional to epilepsy chronicity.

Conclusion:

IrTM could be useful in detecting hypothermic IZ in CD cases. As the ΔT is inversely proportional to epilepsy chronicity, this variable could affect the metabolic thermic patterns of the human brain.

Infrared thermography brain mapping surveillance in vascular neurosurgery for anterior communicating artery aneurysm clipping

Background:

Infrared thermography (IT) is a noninvasive, real-time diagnostic method that requires no contact with the patient and has a broad spectrum of potential applications in neurosurgery. It has been previously demonstrated the high sensitivity and specificity that IT has to detect brain blood flow changes.

Case Description:

The case is based on a 64-year-old diabetic and hypertensive male, to whom an anterior communicating artery (ACoA) incidental aneurysm was discovered. We performed the basal infrared thermography mapping (ITM) and immediately after the transitory clip placement in both A1 segments of the anterior cerebral artery (A1-ACA), we performed a second ITM of the exposed brain cortex. After the definitive clip placement in the neck of the ACoA aneurysm, we removed the transitory clips of both A1-ACA and performed a third ITM of the cortical surface, without finding any cortical cooling or significative temperature differences (Ϫt) compared to the basal ITM. The postoperatory computed tomography (CT) and angio-CT did not show any ischemic damage and confirmed the accurate aneurysm clipping.

Conclusions:

The ITM seems to be a real-time, safe, and useful brain mapping method to identify different temperature zones and temperature dispersion gradients in the human brain cortex. More studies are needed to evaluate the potential applications of IT mapping of the human brain and its use in neurosurgery and vascular neurosurgery.