DISCUSSION
The paranasal sinuses are in close anatomical proximity to vital and delicate structures, such as the skull base, orbit, internal carotid artery, and optic nerve. Broad and detailed anatomical knowledge is essential for surgeons to perform safe and effective procedures.12
With the advent of intraoperative imaging, surgeons have acquired a greater operative domain. Undoubtedly, a thorough knowledge of anatomy is essential to nasal surgeons. Nevertheless, malformations, previous surgeries, and nasal polyposis can make orientation in the surgical field difficult, even for an experienced surgeon.15
Vreudenburg et al. and Dalgorf et al. found a reduction in the likelihood of total, major, and orbital complications in complex ESS procedures with the use of IGS. They included case-control and cohort studies in their systematic reviews, while the current review did not. The small number of clinical trials on the subject was a limitation of our findings; hence, the low incidence of complications in ESS.19,33
Tschopp et al. conducted a case-control study comparing ESS with and without image guidance, and although they did not reach statistical significance for the reduction of complications, they calculated the necessary sample size to achieve significant conclusions regarding the prevention of complications based on their own complication rate. In their analysis, a sample size of at least 880 was necessary to draw reliable conclusions on the subject.34
There is a lack of data in the literature regarding the estimated blood loss. Metson et al. in their prospective cohort found similar data to Singh, with 178.4 ± 18 mL in the IGS group and 149.4 ± 20.1 and no statistical significance (p=0.31).35 Conversely, Tschopp et al. reported 180 ± 124 mL (IGS group) and 201 ± 198 mL (ESS group).34
Despite the limited number of studies that conducted quality of life assessments in patients with CRS who underwent ESS with and without IGS, the evidence suggests a greater improvement in the quality of life of patients operated on with navigation. Due to the heterogeneity of the outcome measures used in the literature, it is difficult to combine or compare data from different studies.27,28
One of the concerns since the inception of image guidance technology is that it would lead to a significant increase in the operative time and therefore increase the procedure cost. Evidence from the literature suggests that IGS does increase the preparation time, but it may lead to a reduction in the incision to suture time, thereby compensating for the overall operating room time.29,31,34,35
In addition to the possible decrease in the complication rate for ESS, the possibility of opening more of the diseased paranasal sinuses is an important question. This review provides important evidence that IGS is more effective than conventional ESS. To the best of our knowledge this is the first paper to present this evidence. Whether this may lead to better patient-reported outcome measures should be the subject of future research.28,31,32
The small number of high-quality studies with a low risk of bias is a limitation of this review. New clinical trials are important to better elucidate the role of image guidance in endoscopic surgery of the paranasal sinus.