Quality of life of patients treated with robotic surgery in the oral and maxillofacial region: a scoping review of empirical evidence

Background There is a blooming trend in the application of robotic surgery in oral and maxillofacial care, and different studies had evaluated the quality of life (QoL) outcomes among patients who underwent robotic surgery in the oral and maxillofacial region. However, empirical evidence on the QoL outcomes from these procedures is yet to be mapped. Thus, this study was conducted to evaluate the available scientific evidence and gaps concerning the QoL outcomes of patients treated with robotic surgery in the oral and maxillofacial region. Methods This study adopted a scoping review design, and it was conducted and reported based on the Arksey and O’Malley, PRISMA-ScR, and AMSTAR-2 guidelines. SCOPUS, PubMed, CINAHL Complete, and APA PsycINFO were searched to retrieve relevant literature. Using Rayyan software, the retrieved literature were deduplicated, and screened based on the review’s eligibility criteria. Only the eligible articles were included in the review. From the included articles, relevant data were charted, collated, and summarized. Results A total of 123 literature were retrieved from the literature search. After deduplication and screening, only 18 heterogeneous original articles were included in the review. A total of 771 transoral robotic surgeries (TORSs) were reported in these articles, and the TORSs were conducted on patients with oropharyngeal carcinomas (OPC), recurrent tonsillitis, and obstructive sleep apnoea (OSA). In total, 20 different QoL instruments were used in these articles to assess patients’ QoL outcomes, and the most used instrument was the MD Anderson Dysphagia Inventory Questionnaire (MDADI). Physical functions related to swallowing, speech and salivary functions were the most assessed QoL aspects. TORS was reported to result in improved QOL in patients with OPC, OSA, and recurrent tonsillitis, most significantly within the first postoperative year. Notably, the site of the lesion, involvement of neck dissections and the characteristics of the adjuvant therapy seemed to affect the QOL outcome in patients with OPC. Conclusion Compared to the conventional treatment modalities, TORS has demonstrated better QoL, mostly in the domains related to oral functions such as swallowing and speech, among patients treated with such. This improvement was most evident within the initial post-operative year. Supplementary Information The online version contains supplementary material available at 10.1186/s12903-024-04035-w.


Background
Robotic surgery is a minimally invasive operative technology that has been shown to provide precise navigation through anatomical orifices, preserving vital structures [1,2].Thus, this surgical approach has mitigated most of the complications in conventional open surgical approaches, offering limited short-term side effects.The technical spectrum of robotic surgical equipment could range from small wristed instruments attached to a robotic arm to completely autonomous systems which can perform the procedure independently [3].They also provide three-dimensional vision, improved surgical dexterity, facilities for telesurgery, better ergonomics and enhanced hand-eye coordination [4].
Complex anatomy in the oral and maxillofacial region causes a significant challenge for conventional surgical approaches.Robotic surgery in the oral and maxillofacial region has been used for various applications such as in cancer treatments, thyroid and parathyroid disease, skull base pathologies and in the management of obstructive sleep apnea (OSA) [5].One of the main complications observed in open procedures is the amount of tissue trauma that could occur due to the large surgical incisions.Moreover, they could result in functional impairment, impaired self-esteem, and decreased quality of life [6].In contrast, robotic surgery has been shown to cause less post-operative pain and low postoperative infections thus, providing a rapid recovery with better cosmetic outcomes [6].
According to the definition proposed by the World Health Organization, quality of life (QOL) means the "individual's perception of their position in life in the context of the culture and value system in which they live and in relation to their goals, expectations, standards and concerns" [7].In the health sector, patient-reported QOL outcomes help to facilitate the evaluation of the impact of a disease or treatment procedure, and allow comparison among different treatment strategies [3].Thus, in an era of minimally invasive concepts, the evaluation of robotic surgery from the perspective of QOL is important.However, QOL outcomes could differ according to the application, anatomical regions, treatment modalities and disease extension.
In relation to robotic surgeries in the oral and maxillofacial region, the available information is unclear regarding the effect of such surgery on QOL outcomes [8][9][10].Although several studies that have demonstrated evidence concerning QOL outcomes on different health conditions; no study is known to have mapped the empirical evidence concerning the QOL outcomes of patients who underwent robotic surgery in the oral and maxillofacial region.Hence, there is a need for such review.This scoping review aimed to map the existing scientific evidence, and to identify evidence gaps, concerning the QOL of patients who underwent robotic surgery in the oral and maxillofacial region.

Design
This scoping review was used to identify the gaps and provide an overview of the available evidence on the quality of life aspect of patients who underwent robotic surgeries in the oral and maxillofacial region.The research design developed by Arksey and O'Malley (2005) was used for the review [11].The review was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis extension for conducting Scoping Reviews (PRISMA-ScR) [12].Additionally, the guidelines in the AMSTAR 2 checklist were used to ensure the quality of the scoping review methodology and reporting process.

Identification of the research question
The scoping review's question was: "What are the available scientific evidence and knowledge gaps in assessing the quality of life of patients treated with robotic surgery in the oral and maxillofacial region?".

Identification of relevant literature
To identify all relevant literature, a systematic search was performed across four databases on 21 January 2023: SCOPUS, PubMed, CINAHL Complete (via EBSCOHost interface), and APA PsycINFO (via EBSCOHost interface) to scoop out all literature addressing the review question.The search was conducted, with the aid of the Boolean operators "OR" and "AND" using the following search terms: "robot", "robotic", "dental surgery", "oral surgery", "maxillofacial surgery", "periodontal surgery", "quality of life", and "wellbeing".The search field was focused on titles, abstracts, and keywords to identify only relevant literature.Tables S1 to S3 (in the Supplementary file) depict the search strings of the literature search strategy for each of the databases used.

Selection of literature
All retrieved literature was imported into the Rayyan software for deduplication.After deduplication, the single-entry literature (deduplicated copies) was screened for eligibility for inclusion in the scoping review.Eligibility for inclusion in this review was based on the following criteria:

Inclusion criteria
• Literature that was peer-reviewed journal articles.
• Literature that was published in English.
• Literature reporting empirical research findings on quality of life of oral and maxillofacial patients treated with robotic surgery.• Literature with accessible full texts.

Exclusion criteria
• Literature that was published in non-peer-reviewed journals.The screening process had two stages and was based on the above inclusion and exclusion criteria.Titles and abstracts screening was performed in the first stage to exclude all non-relevant literature.In the second stage, the full texts of all those studies that were not excluded in the first stage were evaluated for relevance.Only those studies that met all the inclusion criteria were considered eligible for inclusion in the review.Importantly, each stage of the screening process was performed by two independent reviewers who were dental surgeons (the first stage by KKK and AAS and the second stage by DLB and AAS).In situations of conflicts in the inclusion/exclusion of a study, they were resolved through critical discussions between the reviewers.The full texts of the included literature were shared with senior experts (who are professors and coauthors in this scoping review: RDJ and JA) for their review.Literature was retained when there was consensus between the experts and the initial reviewers.The final consensus document was shared with all authors for further review.Any disagreement on studies to include or exclude was resolved by the involvement of the entire team.No authors or institutions were contacted to identify additional sources.

Data charting
From the included literature, data concerning the author names, publication year, country of origin with the robotic system used, study design, study population attributes (disease/application characteristics), QOL instruments, review intervals and the main outcomes were extracted, using a bespoke data extraction sheet (Table 1).

Collation, summary and reporting of results
The extracted data were collated, summarized, and presented in the forms of texts, tables and figures.

Results
One hundred and twenty-three papers were retrieved from the database search (PubMed = 3, SCOPUS = 117, CINAHL Complete = 2, APA PsycInfo = 1).Of these 123 papers, 6 were found to be duplicates and were removed.The remaining 117 papers were screened for inclusion in this review.After two-staged screening, only 18 papers (original research articles) were found eligible for inclusion and were included in this review (Fig. 1; Table S4 (Supplementary file)).

Geographic distribution and study population
In terms of country of origin, all studies were from the USA and Europe and the majority were from the USA (n = 12, 66.67%).Others included three from Italy [13,18,25], two from the United Kingdom [15,19] and one from Denmark [30] (Fig. 2).A total of 804 patients were studied in all the reviewed articles with a minimal sample size of 9 participants [29] to a maximum of 138 [20].The populations mainly varied according to the main pathology and the age groups while in the cohorts of OPC, a significant variation was observed depending on the site of the lesion, human papillomavirus positivity, nodal involvement, and the extent of the lesion.

QOL measures Instruments
In total, 20 different instruments were used to assess various aspects of the QOL.Furthermore, some studies used multiple instruments measuring numerous domains.Except in six studies ( [13,15,17,20,21,23], others used two or more instruments to evaluate the factors that could be related to QOL (Table 2).The most commonly used instrument was the MD Anderson Dysphagia Inventory Questionnaire (MDADI), which evaluates the impact of dysphagia on QOL.

QOL domains assessed, outcomes and factors affecting QOL
Of the physical, psychological, and social functions assessed in the included articles, physical functions related to swallowing, speech and salivary functions were the most assessed aspects (Table 2).Moreover, in patients with OPC, compared to other common treatment modalities such as chemoradiotherapy, most of the studies reported better outcomes in swallowing functions in patients who underwent TORS [14,15,17,27,29,30] (Table 1).It was also noted that speech is minimally affected in TORS procedures [16,21] (Table 1).Some studies also noted improvement in overall oral functions including taste, speech, saliva functions and eating [20,26].However, a significant difference in QOL outcomes was not observed after one year (Table 1).The location of the lesion, the need for unilateral/bilateral neck dissection and adjunctive therapies such as chemoradiation were the main factors affecting QOL (Table 1).Among those patients who underwent tonsillectomy and tongue base reduction due to hypertrophic tongue, they also demonstrated better functional outcomes and improved QOL with TORS [13,19,25] (Table 1).

Discussion
This scoping review aimed to evaluate the available scientific evidence and gaps in the quality of life of patients treated with TORS in the oral and maxillofacial region.Within the studied literature, the application of TORS in the oral and maxillofacial region was limited to the management of OPC, OSA and recurrent tonsillitis.The applied robotic system, da Vinci Robot (Intuitive Surgical Inc., Sunnyvale, CA, USA), provides a magnified three-dimensional high-definition view, a more precise incision due to the wristed instruments that could be bent and rotated better than the human hand and a more reproducible approach compared with traditional open surgical techniques [31].Nevertheless, affordability for the high implementation cost and the availability of training facilities may have contributed to the localization of the TORS to a few countries [32].
Assessment of QOL following a surgery provides a metric-based evaluation of the procedure which could also assist a patient in decision-making [33].In surgeries involving OPC, QOL assessments are mostly based on the preservation of key functions such as speaking, swallowing, and aesthetics.Most of the studies used validated questionnaires specific for the assessment of post-surgical QOL, such as the EuroQol Health Survey (EQ-5D), European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core (EORTC QLQ-C30) and SF-36 Health Survey.Similarly, OSA could affect QOL significantly due to snoring, daytime sleepiness and unrestful sleep.Therefore, QOL could be a reliable parameter to evaluate the functional outcomes of a management protocol.Dysphagia, a well-known drawback of surgeries in the head and neck region, has been extensively assessed in this review using various instruments, including the MDADI, EORTC QLQ-H&N35, UW-QOL, and DS.
Although some studies demonstrated no significant difference between the cohorts [24,26,28], most of the evaluated studies demonstrated a shorter recovery time to reach baseline or better QOL in patients who underwent TORS.The deterioration in QOL in the presence of adjuvant therapy is also worth noting in decision-making on the suitable treatment option.However, as major gaps in the available literature, the absence of long-term effects of TORS on QOL and the lack of properly designed randomized controlled trials could be highlighted.
The comprehensive search strategy in four large databases and the minimally biased review protocol adhered to in this review were the main strengths.Additionally, the main findings of this review enhanced the literature by emphasizing the outcomes specific to robotic surgeries in the head and neck area and the gaps that need to be addressed in future studies.
Nevertheless, the studies included in this review have their own limitations.To start with, TORS needs specific training to develop the required skill expertise for the best outcome; however, bias due to the possible impact of the operator's skills on the surgical outcome were not discussed extensively in any of those studies, except for the study by Arora et al. [19] where it was identified as a possible bias.Other identified limitations included small sample sizes [13, 16, 19-21, 24, 29, 30], selection bias due to inclusion of newly diagnosed patients [19,20,23,24], and absence of control group in some studies [15,19,21].Additionally, the comparison group in most of the included studies underwent adjuvant therapy under various management protocols, and this could have significantly affected the post-operative QOL they reported [17,18,22].Varying survey time points [13,15,17,22,29], lack of pre-operative QOL data [13,27,28] and lack of long-term follow up [21] were also mentioned as possible limitations in the included studies.
Aside from the limitations of the included studies, this scoping review itself also has its own limitations.First, all articles considered for this scoping review were in English; hence, the possibility of non-inclusion of articles published in other languages could not be overruled in this review.Also, the variations in the study characteristics (such as study design) as well as those variations concerning the evaluated QOL aspects in the included studies may have limited the opportunity for a more extensive comparison of the outcomes reported in the included studies.Most of the reviewed assessments were also based on patient-reported outcomes; hence, the possibility of recall bias may exist in such outcomes, making the mapped evidence not absolutely accurate due to this possible bias.Furthermore, this review did not find any relevant randomized controlled trial for inclusion.However, randomized controlled trials are considered the gold standard in evaluating a treatment outcome; hence, the conclusion of this review should be interpreted with caution.

Conclusion
Within the limitations in this scoping review, compared to the conventional treatment modalities, TORS has demonstrated better quality of life, mostly in the domains related to oral functions such as swallowing and speech, among patients treated with such.This improvement was most evident within the initial post-operative year.However, it is worth noting the heterogeneity of the study designs and the applied QOL instruments in the existing literature.Thus, properly designed prospective longitudinal cohort studies as well as randomized controlled trials, assessing similar aspects in QOL, would be needed to provide better evidence.

Table 1 Summary of the included studies No Authors (Year) Country (Robotic system) Study Design Population Characteristics Conditions Treated Assessed QOL domains & QOL instruments Duration of the assessment Outcomes & limitations
CRTTable 1 (continued) come Table 1 (continued)

Table 2
Different instruments used for the measurements of QOL aspects