Health-related quality of life in patients with nasal prosthesis

Exploring digital technologies used in the design and manufacture of craniofacial implant surgical guides: A scoping review

STATEMENT OF PROBLEM

Unlike intraoral implants, digitally planned surgical templates used for guiding the ideal position of the craniofacial implants are not well established, and clear methods and guidelines for their design and construction are lacking.

PURPOSE

The purpose of this scoping review was to identify the publications that used a full or partial computer-aided design and computer-aided manufacture (CAD-CAM) protocol to create a surgical guide that achieves the correct positioning of craniofacial implants to retain a silicone facial prosthesis.

MATERIAL AND METHODS

A systematic search was conducted in MEDLINE/PubMed, Web of Science, Embase, and Scopus for articles published before November 2021 in the English language. Articles needed to satisfy the eligibility criterion of in vivo articles that created a surgical guide with digital technology for inserting titanium craniofacial implants to hold a silicone facial prosthesis. Articles that inserted implants in the oral cavity or upper alveolus only and articles that did not describe the structure and retention of the surgical guide were excluded.

RESULTS

Ten articles were included in the review; all were clinical reports. Two of the articles used a CAD-only approach alongside a conventionally constructed surgical guide. Eight articles described applying a complete CAD-CAM protocol for the implant guides. The digital workflow varied considerably depending on the software program, design, and retention of guides. Only 1 report described a follow-up scanning protocol to verify the accuracy of the final implant positions compared with the planned positions.

CONCLUSIONS

Digitally designed surgical guides can be an excellent adjunct to accurately place titanium implants in the craniofacial skeleton for support of silicone prostheses. A sound protocol for the design and retention of the surgical guides will enhance the use and accuracy of craniofacial implants in prosthetic facial rehabilitation.

Approach to Major Nasal Reconstruction: Benefits of Staged Surgery and Use of Technology

This article reviews special considerations in complex nasal defects including treatment of adjacent subunit defects, timing of repair with radiation, reconstruction in patients with prior repairs or recurrent disease, and the role of prosthetics. The role of technological advances including virtual surgical planning, 3 dimensional printing, biocompatible materials, and tissue engineering is discussed.

Prosthetic Nasal Reconstruction

Prosthetic nasal reconstruction provides a restorative option for patients with nasal defects, and these can be retained with a variety of methods including adhesives and implants. These prostheses can significantly improve appearance, self-esteem, and quality of life for patients and they restore many functions of the external nose. Traditional fabrication methods are often used by the skilled professionals who make these custom prostheses, but digital technology is improving the workflow for design and fabrication of silicone nasal prostheses. Nasal prosthetic reconstruction requires multidisciplinary coordination between surgeons, maxillofacial prosthodontists, anaplastologists, and other members of the healthcare team. Prosthetic treatment can be considered as an alternative to, or an addition to treatment with surgical reconstruction.

Perception of color mismatch or conspicuous marginal adaptation in extraoral prostheses with eye-tracking

STATEMENT OF PROBLEM

Color matching and marginal integrity are major challenges when providing extraoral maxillofacial prostheses. Which of the color and marginal harmony features are more important for the extraoral prostheses to be inconspicuous is unclear. Studies on the perception of these prostheses with objective evaluation criteria are lacking.

PURPOSE

The purpose of this observational study was to investigate the significance of color mismatch and conspicuous marginal adaptation in the perception of extraoral maxillofacial prostheses using eye-tracking technology. The secondary aim was to evaluate the perception of extraoral maxillofacial prostheses with regard to the observers' sex.

MATERIAL AND METHODS

Twenty-seven face images, in 3 groups, representing well-fitting orbital prostheses with a color mismatch (IC), prostheses with a good color match but distinct marginal adaptation (IM), and symmetrical face images, were viewed for 5 seconds by 52 laypeople. Time to first fixation (TFF), fixation duration (FD), and fixation count (FC) at defined areas of interest were recorded and analyzed by an eye-tracking device. Because of the nested structure of data, a sex- and age-adjusted random intercept linear mixed effects model was used to assess the difference between IC, IM, and SI. Bonferroni corrected P values were used for pairwise comparisons. The difference between observers' sex was evaluated with random intercept mixed model by adjusting for age for each image. For repeated measurement analysis, the lm4, lmerTest, and emmeans libraries in R version 4.3.1 (R Foundation for Statistical Computing) were used (α=.05 for all tests).

RESULTS

Significant differences were found between the symmetrical image group and other study groups at the facial prosthesis region in all parameters (each P<.001). Observers first focused on the facial prostheses in IC (0.72 seconds) and in IM (0.789 seconds). Longer fixation durations, 1.909, 1.989 seconds for IC and IM (PIC<.001, PIM<.001), respectively, and a higher fixation count for IC (5.28) (P<.001) and for IM (5.45) (P<.001) were recorded on facial prostheses compared with other areas of interest. Women were more focused on the prosthesis than men in the IC and IM groups considering FD (PIC=.003, PIM<.001) and FC values (PIC=.016, PIM<.001, PSI<.001). Fixation duration for women and men was 2.097 seconds and 1.739 seconds in the IC group, 2.219 seconds and 1.78 seconds in the IM group, and 1.364 seconds and 1.222 seconds in the SI group, respectively.

CONCLUSIONS

Since the color mismatch and distinct marginal adaptation of maxillofacial prostheses were recognized using eye-tracking technology, both features appeared to be equally significant to be considered in fabrication procedures.

Salvage Strategies for Local Recurrences of Squamous Cell Carcinoma of the Nasal Vestibule: A Single-Center Experience of 22 Years

Squamous cell carcinomas of the nasal vestibule are an extremely rare neoplastic disease. Although brachytherapy is gaining popularity for primary treatment, surgery remains the best option in case of recurrences. The aim of this paper is to outline our treatment experience of local recurrence of SCCNVs over the past 22 years. We retrospectively reviewed the clinical data of the patients who underwent surgical treatment for local recurrence of SCCNV: data regarding age, sex, primary tumor treatment, recurrence location and time of appearance, surgical resection, type of reconstruction, postoperative complication, surgical revision, and re-recurrence rate were analyzed. Twenty patients were included in the study. The median period for recurrence appearance was 17 months, and the prevalent location of recurrence was the nasal alae. Prevalent reconstructive procedures were the nasolabial flap and paramedian forehead flap. No postoperative complications were observed, and one case of re-recurrence was detected at 12-months of follow-up. Based on our experience, salvage surgical procedures for SCCNV recurrences must be individualized and carefully planned, taking into account the peculiar pattern of tumor spread and the presence of scar and heavily radiotherapy damaged tissue from previous treatment; delayed reconstruction should be considered for all the cases with skeletal involvement.

Customized Nasal Prosthesis for a Jones Lacrimal Bypass Tube Using 3-Dimensional Planning and Printing Technology

A 35-year-old woman was treated for extensive squamous cell carcinoma of the nasal septal mucosa with total rhinectomy, including removal of the nasal septum, and chemoradiotherapy. A magnet-retained nasal prosthesis was fitted. She had developed right-sided epiphora from total proximal lacrimal canalicular obstruction, for which an angled Jones lacrimal bypass tube was inserted. The tube, however, intermittently rotated in the nasal cavity, causing recurrent epiphora and irritation at the caruncular site. With the aid of 3-dimensional technology, we designed a septum for the prosthesis that stabilized the tube within the nasal cavity. At the follow-up 2 years later, the patient was satisfied with the nasal prosthesis and lacrimal stent. To our knowledge, this report is the first to describe a patient-specific nasal prosthesis adapted for a Jones tube after total rhinectomy.

Reconstructive Options after Oncological Rhinectomy: State of the Art

BACKGROUND

The nose is a central component of the face, and it is fundamental to an individual's recognition and attractiveness. The aim of this study is to present a review of the last twenty years literature on reconstructive techniques after oncological rhinectomy.

METHODS

Literature searches were conducted in the databases PubMed, Scopus, Medline and Google Scholar. "Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA)" for scoping review was followed.

RESULTS

Seventeen articles regarding total rhinectomy reconstruction were finally identified in the English literature, with a total of 447 cases. The prostheses were the reconstructive choice in 213 (47.7%) patients, followed by local flaps in 172 (38.5%) and free flaps in 62 (13.8%). The forehead flap (FF) and the radial forearm free flap (RFFF) are the most frequently used flaps.

CONCLUSIONS

This study shows that both prosthetic and surgical reconstruction are very suitable solutions in terms of surgical and aesthetic outcomes for the patient.

Nasal Cavity Squamous Cell Carcinoma: Factors Associated With Treatment Outcomes and Potential Organ Preservation

Background

Squamous cell carcinoma of the nasal cavity (NCSCC) is a rare, challenging malignancy. Surgical resection of this tumor can cause significant facial deformity, and indications for adjuvant or organ preservation therapies are not well-described.

Objective

To examine the impact of treatment regimen on survival outcomes in NCSCC and to compare surgical to non-surgical based therapies.

Methods

The National Cancer Database was queried for NCSCC from 2004 to 2014. Patient demographics, tumor characteristics, and treatment regimen were compared for the entire cohort. Multivariable Cox proportional hazards regression was performed for statistical analysis of treatment regimen and surgical margins on overall survival (OS) for early and late-stage disease.

Results

A total of 1883 NCSCC patients were identified. The OS for the cohort was 83 months, and median age at diagnosis was 65 years. NCSCC patients who underwent surgery followed by adjuvant radiation therapy (RT) had a better OS compared to definitive RT (HR: 0.58, P < .001). In early stage NCSCC (T1/T2, N0), there was no significant difference in OS between patients treated with surgery only or surgery with adjuvant RT compared to definitive RT. In advanced stage NCSCC, surgery with adjuvant RT had a better OS compared to definitive chemoradiation. Having positive margins was shown to predict a worse OS when compared to negative margins in surgical patients despite adjuvant RT or chemoradiation.

Conclusions

NCSCC appears to be best treated with surgery followed by adjuvant RT in advanced-stage disease whereas in early-stage disease, surgery does not improve OS compared to definitive RT.

Facial Scanning and Additive Manufacturing Used in Production Nasal Prosthesis

Maxillofacial prosthesis is an effective treatment for patients with facial sequelae, but it remains challenging for professionals due to its high esthetic complexity. This study describes a clinical case of successful nasal prosthetic rehabilitation using digital technology and additive manufacturing. Initially, the 76-year-old patient, with a facial defect in the nasal region, had her face scanned with 3-dimensional scanner for laboratory planning of the prototype of a nasal prosthesis. After approving the prototype image, working models in muffle shape were obtained in additive manufacture for the inclusion of the prosthesis. In the final session, the prosthesis was colored extrinsically and installed. The procedures digital in the manufacture of the facial prosthesis was applicable and agile, allowing the professional greater predictability regarding the shape of the rehabilitated organ, esthetic improvement in the mutilated area and patient satisfaction in relation to the speed, of the procedure and the quality of the prosthesis.

Outcome measures in facial prosthesis research: A systematic review

STATEMENT OF PROBLEM

Facial prosthesis research uses a wide variety of outcome measures, which results in challenges when comparing the effectiveness of interventions among studies. Consensus is lacking regarding the most appropriate and meaningful outcome measures to use in facial prosthesis research to capture important perspectives.

PURPOSE

The purpose of the systematic review was to identify and synthesize outcome measures used in facial prosthesis research.

MATERIAL AND METHODS

Electronic searches were performed in 11 databases (including nonpeer-reviewed literature). The citations were searched, and expert societies were contacted to identify additional studies. Inclusion criteria comprised studies of participants with facial defects who required or had received prosthetic rehabilitation with an external facial prosthesis. Exclusion criteria comprised participants with ocular prostheses, case reports, case series with fewer than 5 participants, laboratory-based studies, and studies published before 1980. Study selection was performed independently by 2 reviewers. Discrepancies were resolved through discussion or by a third reviewer. Outcome measures were synthesized with a categorization approach based on the perspective, theme, and subtheme of the outcome measures. Quality assessment was performed with an appraisal tool that enabled evaluation of studies with diverse designs.

RESULTS

Database searching identified 13 058 records, and 7406 remained after duplications were removed. After initial screening, 189 potentially relevant records remained, and 186 full texts were located (98% retrieval rate). After full-text screening, 124 records were excluded. Citation searches and contact with expert societies identified 4 further records. In total, 69 articles (grouped into 65 studies) were included. Studies were categorized as per the perspective of their outcome measures, with the following findings: patient-reported (74% of studies), clinical indicators (34%), clinician-reported (8%), multiple viewpoints (6%), and independent observer-reported (3%). Patient-reported outcome measures included tools to assess satisfaction, quality of life, and psychologic health. Variability in the choice of outcome measures was evident among the studies, with many self-designed, unvalidated, condition-specific questionnaires reported. A greater number of outcome measure themes emerged over time; themes such as service delivery and health state utility have recently been evaluated.

CONCLUSIONS

Over the past 40 years, facial prosthesis research has focused on patient-reported outcome measures. Outcome measures relating to other perspectives have been used less frequently, although new themes appear to be emerging in the literature. Future research should use outcome measures with appropriate measurement properties for use with facial prosthetics.

Radiotherapy as nose preservation treatment strategy for cancer of the nasal vestibule: The Dutch experience

BACKGROUND AND PURPOSE

Primary radiotherapy is often preferred for early-stage cancer of the nasal vestibule (CNV), combining high disease control with preservation of nasal anatomy. However, due to practice variation and an absence of comparative trials, no consensus exists on preference for brachytherapy (BT) or external beam radiotherapy (EBRT). We compared these modalities in terms of disease control, nose preservation rates and toxicity.

MATERIALS AND METHODS

Medical records of 225 patients with T1-T2 squamous cell carcinoma of the nasal vestibule treated with 3D image-guided primary radiotherapy between Jan 2010 and Dec 2016 in 6 Dutch institutions were reviewed retrospectively.

RESULTS

153 of 225 patients were treated with BT, 65 with EBRT and 7 with other modalities. Median follow-up was 46 months. Overall 3-year local control (LC) and regional control (RC) were 87% and 89%. Five-year disease-specific survival (DSS) and overall survival (OS) were 94% and 82%. Three-year survival with preserved nose (SPN) was 76%. BT provided higher 3-year LC (95% vs 71%, p < 0.01) and SPN compared with EBRT (82% vs 61%, p < 0.01). Multivariable and propensity-score-matched cohort analyses confirmed better outcomes after BT. No difference was seen in DSS or OS. Five-year incidence of CTCAE 5.0 grade ≥2 toxicity was higher after BT (20% vs 3%, p = 0.03) and consisted mostly of radiation ulcers. 50% of all late toxicity recovered.

CONCLUSION

In this largest-to-date multicenter analysis of T1-T2 CNV, BT achieved superior LC and SPN compared with EBRT. Grade 1-2 radiation ulcers occurred more frequently after brachytherapy, but were transient in half the cases. Considering these results, BT can be recommended as first-line treatment for T1-T2 CNV.

The challenge of managing oral maxillofacial rehabilitation with quality and cost-benefit

Although orofacial cancer leads to substantial functional, esthetic, and psychosocial deficits for patients, reconstructive plastic surgeries may not be indicated for large facial defects. The high costs of prosthetic oral maxillofacial rehabilitation may hamper such treatment, which commonly involves virtual planning, craniofacial implants, and computer-aided design and computer-aided manufactured prostheses. This report shows the treatment of 2 patients with large facial defects from surgical resection of cancerous tissue who were rehabilitated with implant-supported bar-clip overdentures and facial prostheses fabricated by using low-cost straightforward methods.

Epithetic nasal reconstruction after total rhinectomy: Oncologic outcomes, immediate and long-term adverse effects, and quality of life

INTRODUCTION

Total rhinectomy for tumors of the nasal cavity substantially alters patients' appearance and requires local reconstruction. While full nasal epitheses are well-established for this purpose, potential long-term adverse effects and impact on patients' quality of life are not fully understood.

METHODS

Sixteen patients who underwent total rhinectomy with ensuing nasal reconstruction with a full nasal epithesis were included in the study. Oncologic outcomes were assessed, and adverse effects and quality of life analyses were performed based on a patient-reported outcomes tool.

RESULTS

In patients with squamous cell carcinomas of the nasal cavity, total rhinectomy led to excellent local tumor control. Immediate and long-term adverse effects of total rhinectomy and placement of a nasal epithesis were predominantly limited to the immediate nasal region. While patients were satisfied with their nasal appearance, they reported a worse assessment of their facial appearance and a measurable long-term effect on their psychological well-being.

CONCLUSION

Total rhinectomy and reconstruction with a full nasal epithesis is a safe and oncologically sound treatment approach. However, its effects on patients' overall appearance and psychological well-being need to be considered during treatment planning and follow-up.

Using digital technology to create a custom esthetic bandage for patients after rhinectomy

Patients undergoing partial or total rhinectomy surgeries are left with a lifelong facial defect that poses psychosocial and functional challenges. The extended postoperative healing period after rhinectomy can delay the timely restoration of a patient's nose by definitive prosthesis when conventional impression methods are used. The treatment workflow for fabricating a custom esthetic nasal bandage with the use of digital technology is introduced to avoid the conventional preoperative impression, as well as to allow for immediate delivery at the postoperative follow-up visit.

Implant-Retained Nasal Prosthesis with Bar and Clip for a Patient with Total Rhinectomy: A Clinical Report

The present clinical report describes the fabrication of an implant -retained prosthesis with bar and clip retention for a patient with total rhinectomy due to basal cell carcinoma (BCC). The nasal prosthesis was retained on the face by a reverse Y-shaped bar with horizontal and vertical extensions, resulting in favorable retention and function.

Health utility of rhinectomy, surgical nasal reconstruction, and prosthetic rehabilitation

OBJECTIVES

Advanced nasal malignancies may require rhinectomy, which can have profound psychosocial impacts. Rhinectomy defects can be rehabilitated through surgery or prosthetics. We seek to understand the health utility of the rhinectomy defect, surgical, and prosthetic reconstruction, which have not been previously studied.

STUDY DESIGN

Prospective clinical study METHODS: Adult naïve observers (n = 273) ranked the utility of five randomized health states (monocular blindness, binocular blindness, post-rhinectomy nasal defect, postsurgical reconstruction, and post-prosthetic rehabilitation). Health utilities were measured using visual analogue scale (VAS), standard gamble (SG), and time trade-off (TTO). One-way analysis of variance (ANOVA) with post hoc Scheffe's test and the independent samples T-test for a priori comparisons were performed. Multiple linear regression was performed using participant demographics as independent predictors of utility scores.

RESULTS

Health utilities (VAS, SG, TTO) were reported as follows (mean ± SD): monocular blindness (0.71 ± 0.21, 0.84 ± 0.20, 0.85 ± 0.19), binocular blindness (0.48 ± 0.25, 0.68 ± 0.28, 0.63 ± 0.28), post-rhinectomy nasal defect (0.59 ± 0.24, 0.74 ± 0.24, 0.74 ± 0.24), postsurgical reconstruction (0.88 ± 0.16, 0.90 ± 0.18, 0.89 ± 0.13), and post-prosthetic rehabilitation (0.67 ± 0.22, 0.80 ± 0.23, 0.82 ± 0.20). Both surgical reconstruction (P < .001) and prosthetic rehabilitation (P < .001) significantly improved health utility. SG and TTO utility scores were inversely associated with observer age (P < .001) and participants who identified themselves as non-Caucasians (P < .05) in post-rhinectomy nasal defect, post-nasal surgical reconstruction, and post-nasal prosthetic rehabilitation health states, while higher levels of education were directly associated with SG scores (P < .05), respectively.

CONCLUSION

This is the first study to demonstrate the significant negative impact of the rhinectomy nasal defect on health utility. Rehabilitation by surgical or prosthetic techniques significantly increases health utility as rated by naïve observers. Laryngoscope, 130:1674-1679, 2020.

Tumor Control and Quality of Life in Skin Cancer Patients With Extensive Multilayered Nasal Defects

OBJECTIVES

The reconstruction after nasal skin cancer (NSC) resection is often practiced differently. The objective of this study is to evaluate the influence of patient-, tumor- and management-related factors on the role of surgery and choice of reconstruction.

METHODS

This was a monocentric retrospective study of patients who were diagnosed with a NSC (squamous cell or basal cell carcinoma) and suffered from an extended defect after ablative surgery between 2003 and 2013. Twenty-five patients were included. Tumors were staged using the Union for International Cancer Control (eighth edition) TNM classification for primary cutaneous skin cancer of the head and neck. Preferred treatment was surgery in all patients. Health-related quality of life (HRQoL) measurement was evaluated by one generic (36-Item Short Form Health Survey [SF-36]) and two organ-specific questionnaires (Rhinoplasty Outcome Evaluation [ROE] and Functional Rhinoplasty Outcome Inventory 17 [FROI-17]) after therapy. Survival data were estimated by the Kaplan-Meier method and statistical analysis was performed by log-rank, analysis of variance, Levene's and t-tests. The median follow-up time was 2.1 years.

RESULTS

According to the Union for International Cancer Control classification, 13 of 25 tumors were staged as pT1 (52%), four as pT2 (16%), seven as pT3 (28%) and one as pT4a (4%). Seventy-two percent of patients (n=18) chose plastic reconstruction, and for the remaining 28% (n=7) of the patients opted for an implant-retained prosthesis. The overall survival was 69.5% after 5 years, the 5-year recurrence-free survival was 90.9% and the 5-year disease-specific survival was 100%. There was no significant difference in the HRQoL outcome between both rehabilitation methods.

CONCLUSION

Surgery in NSC gives an excellent oncologic prognosis. Nasal reconstruction and prostheses are both very viable options depending on tumor stage and biology, the patient's wishes as well as the experience of the surgeon.

Organ preservation for patients with anterior mucosal squamous cell carcinoma of the nasal cavity: Rhinectomy-free survival in those refusing surgery

BACKGROUND

Standard treatment of squamous cell carcinoma (SCC) of the anterior nasal mucosa is surgical resection with or without postoperative radiation.

METHODS

Retrospective review of patients diagnosed with SCC of the nasal cavity between January 2000 and July 2018 who refused total rhinectomy and who were treated with radiation with or without chemotherapy with curative intent.

RESULTS

Eleven patients were identified, 73% had stage III or stage IV disease. Four patients were treated with intensity-modulated radiotherapy and seven with intensity-modulated proton radiotherapy. Concurrent chemoradiotherapy was used in nine patients (82%). With a median follow-up of 15 months (3-124 months), two patients experienced recurrence and one developed distant metastasis and died from disease. The 2-year rhinectomy-free survival rate was 88%. Two-year overall survival and recurrence-free survival were 100% and 75%, respectively.

CONCLUSION

A radiation-based approach for SCC of the nasal cavity mucosa is a valid option for selected patients who refuse up-front surgery.

Health-related quality of life in patients with major salivary gland carcinoma

PURPOSE

To evaluate the health-related quality of life (QOL) in patients with major salivary gland carcinoma (MSGC).

METHODS

45 patients with MSGC completed the University of Washington Quality of Life (UWQOL) questionnaire. Results and factors influencing quality of life were analyzed using Mann-Whitney U test.

RESULTS

24 patients were male, 21 patients were female, and median age was 57 years. 33 patients presented with early stage (UICC stage I or II) cancer. All patients had surgery as initial therapy. The UWQOL domains with the worst results were 'appearance', 'activity' and 'anxiety'. Factors influencing QOL were sex, tumor stage, comorbidities, follow-up time, tumor grade, postoperative radiation therapy and facial nerve dysfunction.

CONCLUSIONS

Diagnosis and treatment of MSGC has influence on overall QOL. Postoperative radiation has the greatest impact on QOL. This is one of the largest study evaluating QOL in patients with salivary gland carcinoma using the UWQOL.

Aesthetic and functional outcomes in patients with a nasal prosthesis

The aim was to evaluate the aesthetic and functional outcomes in patients with a nasal prosthesis after radical tumour resection. A questionnaire with 15 domains was created to evaluate the satisfaction of patients with their nasal prosthesis. Correlations with the results of the University of Washington Quality of Life (UWQOL) questionnaire, which was also completed by the patients, were analyzed. Forty-three patients with a partial or total nasal prosthesis completed the questionnaire. Twenty-seven patients were male and 16 were female; their median age was 62 years. The median follow-up time after tumour resection was 33 months. The best result was obtained for overall function (85.5) and the worst result for nasal crusts (58.5). The average daily duration of prosthesis use was 17.4h. There were sex-dependent and age-dependent differences in the domain 'self-confidence', age-dependent differences in the domain 'stability during sporting activities', and differences in the domain 'nose bleed' depending on the time since tumour resection. All patients would recommend this rehabilitation after rhinectomy. 'Satisfaction with function' had the most influence on UWQOL domains. The nasal prosthesis is a well-accepted rehabilitation after rhinectomy. The results for appearance are comparable to those obtained for nasal reconstruction, and high scores were found for the functional domains.