Robust marker detection and high precision measurement for real-time anatomical registration using Taguchi method

BACKGROUND

Accurate autonomous marker detection and measurement is essential for high precision anatomical registration. The measurement should be in real-time, accurate, and robust to the varied conditions of the operation theatre.

METHODS

The purpose is to design and implement a robust real-time algorithm to measure the coordinates of the point on the marker for robot-based autonomous registration and surgery. The algorithm is built in two parts based on the recursive Taguchi method. The first part deals with the detection of markers. In the second part, the center of the marker is located, and the coordinates are measured by fitting the concentric ellipse.

RESULTS

Three case studies are presented where the algorithm is tested for extreme conditions of uneven lighting, distorted color, surface distortions, and significant random orientation of the marker. The robustness of the algorithm in successfully detecting and measuring in real-time is presented.

CONCLUSION

The algorithm is successfully implemented for real-time detection and coordinate measurement of the markers.

Validation of High Precision Robot-Assisted Methods for Intracranial Applications: Preliminary Study

BACKGROUND

This work attempts to simulate a robot-based autonomous targeted neurosurgical procedure such as biopsy on a vegetable specimen. The objective of the work is to validate the robot-based autonomous neuroregistration and neuronavigation for neurosurgery in terms of stereotactic navigation and target accuracy.

CASE DESCRIPTION

A vegetable (carrot) fixed in a tray was used as a model. The tray was affixed with multiple markers. The robot autonomously registers the subject precisely and subsequently accesses the target. The navigation trajectory closely follows the path from the entry point to the target point, as specified in the medical image. The replication of procedures reveals that the target accuracies are within 1 mm. The results based on the case studies are presented. Intricate cases in terms of entry hole size, depth, and size of the target are considered for both phantom and vegetable trials.

CONCLUSIONS

The results of the case studies show enhanced and consistent performance characteristics in terms of accuracy, precision, and repeatability with the added advantage of the economy of time. The case studies serve as validation for a high precision robot-assisted neuroregistration and neuronavigation task for neurosurgery and pave the way for further animal and human trials.

Critical appraisal of the existing and emerging therapies for smoking cessation

Smoking is a major health problem of the society as it causes a wide variety of health hazards and produces a strong addictive behavior. Various pharmacological and non pharmacological treatments have been tried for smoking cessation from time to time. Some of the pharmacological treatments have been able to achieve the status of first line and second line therapy for smoking cessation by the US Public Health Service Clinical Practice Guideline. Some newer and very promising drugs have come up and are in the clinical trials for establishment of their efficacy. While some other drugs have been tried from time to time but have failed to show any consistent results. Various non pharmacological therapies like behavioural therapy are also of utmost importance in this regard. This article gives a brief review and critical assessment of the existing and the emerging smoking cessation therapies.

Clinical evaluation of two antiemetic combinations palonosetron dexamethasone versus ondansetron dexamethasone in chemotherapy of head and neck cancer

INTRODUCTION

Palonosetron and ondansetron are two selective 5-hydroxytryptamine (5-HT3) receptor antagonists that have shown remarkable efficacy in controlling nausea and vomiting following administration of moderately emetic anticancer chemotherapy. Their efficacy is enhanced by the concurrent administration of dexamethasone. In the present study, we aimed to compare the antiemetic efficacy of a palonosetron plus dexamethasone (PD) schedule versus an ondansetron plus dexamethasone (OD) schedule.

METHODS

A randomised, crossover trial was conducted in 30 patients with head and neck cancer who were receiving moderately emetogenic chemotherapy. The patients were divided into two groups. In the first cycle, one group was given a PD schedule and the other, an OD schedule. For the subsequent cycle, crossover of the antiemetic schedules was done. The antiemetic effects were evaluated by recording the intensity of nausea and the frequency of vomiting in the acute and delayed phases.

RESULTS

Complete response in the acute phase was observed in 83.3 percent of the patients on the PD schedule and in 80 percent of those on the OD schedule. In the delayed phase, complete response was observed in 76.7 percent and 66.7 percent of the patients on the PD schedule and OD schedule, respectively. The overall rate of complete response was 66.7 percent in the PD group and 46.7 percent in the OD group. In the PD group, there were 73.3 percent of nausea-free patients as opposed to 66.7 percent in the OD group.

CONCLUSION

The results suggest that the PD schedule was superior to the OD schedule in controlling emesis in cancer chemotherapy, although this difference was not statistically significant.