Cysts of the maxillary sinus: a literature review

Imaging of Odontogenic Sinusitis

Odontogenic sinusitis (ODS) has been shown to be the most common cause of unilateral maxillary sinus opacification on computed tomography scans. Review of the maxillary alveolar ridge and maxillary tooth roots, and their relationships to the maxillary sinus floor is essential when interpreting paranasal sinus imaging. In recent years, ODS has received increased attention in the recent otolaryngologic and dental literature. This article will discuss technical considerations to optimize imaging of the paranasal sinuses and maxillary dentition, as well as both classic and nuanced radiologic findings of ODS.

Maxillary Sinus Augmentation and Implant Installation in Patients With Pseudocysts and Mucous Retention Cysts

This case study systematically assessed diverse approaches to sinus augmentation in the presence of sinus pathology. Three patients were carefully selected and categorized as pseudocyst (PsC) (type 1), mucous retention cyst (MRC) smaller than 20 mm (type 2), and MRC larger than 20 mm in size (type 3). All patients underwent sinus augmentation procedures, with each case utilizing a unique surgical approach. Spontaneous drainage was performed for the patient with PsC (type 1), followed by uncomplicated sinus augmentation. For the patient with an MRC smaller than 20 mm (type 2), aspiration of the cyst contents preceded sinus augmentation. Conversely, the patient with a larger MRC (type 3) underwent cyst enucleation followed by sinus augmentation after complete recovery of the sinus membrane. No complications were noted in any of the cases, and follow-up revealed stable implant installation at the site of sinus augmentation. Within the constraints of this study, the choice of surgical procedure, whether involving spontaneous drainage, aspiration, or enucleation, should be guided by an anticipated pathologic diagnosis and the size of the sinus cyst. This informed approach empowers clinicians to make well-informed decisions for the best possible outcomes and sustained results. Overall, this study offers valuable insights for clinicians seeking to optimize sinus augmentation procedures in the presence of sinus pathology.

Relationship of the accessory maxillary ostium to mucosal thickening and maxillary sinus cysts: a 3D segmentation study

OBJECTIVES

We aimed to investigate the relationship between the presence of the accessory maxillary ostium (AMO) with mucosal thickening (MT) and maxillary sinus cysts (MSCs).

STUDY DESIGN

This single-center retrospective study included patients who underwent paranasal sinus computed tomography (CT) between November 2022 and February 2023. We excluded patients with natural maxillary ostium (NMO) occlusion. Two radiologists evaluated the presence of AMOs, MT, and MSCs in CT images and measured their dimensions using a three-dimensional volumetric analysis program.

RESULTS

We included 125 patients (mean age: 36.47 ± 16.0 years; male/female: 67/58). In total, 65 patients (52%) had single or multiple AMOs. No significant relationship was found between the presence of an AMO and the presence of MT on either side (P ≥ .306). There was a statistically significant difference between the presence of an AMO and MSC on the right side (P = .002), but not on the left side (P = .477). The diameter of the AMO and the distance from the AMO to the maxillary sinus floor were not correlated with mucosal thickness or MSC volume, but the distance from the AMO to the sinus floor had a small positive correlation with total maxillary sinus volume.

CONCLUSIONS

The presence of an AMO and its increased diameter may not contribute to ipsilateral maxillary sinusitis in patients whose unilateral or bilateral NMOs are not occluded.

Severe facial pain and removal of maxillary sinus mucous retention cyst

Maxillary sinus retention cysts (MRCs) are typically asymptomatic and require no treatment. An early 30s man presented with a decade-long history of severe left-sided chronic facial pain (CFP). Multiple prior treatments resulted in an edentulous patient with persistent pain. Imaging revealed a dome-shaped radiopaque change in the left maxillary sinus. History and clinical examination suggested persistent idiopathic facial pain, and doubts about the outcome of a surgical intervention were explained to the patient. Surgical removal of the MRC via lateral antrotomy led to complete symptom resolution of CFP. This case substantiates the importance of considering MRCs as a possible cause of CFP. It also emphasises the need for a systematic multidisciplinary approach in cases of unexplained CFP.

A Retrospective Analysis of Clinicopathological Features in 117 Isolated Maxillary Sinus Pathologies in a Tertiary Care Hospital

Diagnosis of maxillary sinus pathologies is challenging. Herewith we describe the clinicopathological features in isolated maxillary sinus lesions in tertiary care hospital in Goa, India. The retrospective study included patients treated between 2017 and 2022, of all age groups and gender, who underwent either a biopsy or surgery, providing a histopathological diagnosis. Of the 117 pathologies, 88 (75.2%) were non-neoplastic. The overall frequency of pathologies were polyp in 40.2%, fungal lesions (18.8%), malignancy (13.7%), chronic rhinosinusitis (11.9%) and inverted papilloma (10.3%). There were 71 men (60.7%) and 46 women (39.3%). There were 10 patients (8.5%) below 20 years of age, of which 8 patients (80%) had non-neoplastic pathology. Common comorbidities were diabetes and hypertension, while symptoms were nasal blockage (75.2%), nasal discharge (47%) and ocular redness (16.2%). Each pathology was evaluated for demography, side of lesion, comorbidity, and symptoms. Most isolated maxillary sinus pathologies were benign lesions. However, a strong clinical suspicion and histopathological confirmation is needed for all lesions in all age groups due to a risk of malignancy.

Relationship between maxillary sinus mucosal cyst and sinus ostium 2D area in three-dimensional volumetric paranasal CT ımages

OBJECTIVE

To investigate the relationship between the maxillary sinus ostium 2D area (SOA) and the development of mucosal cysts of the maxillary sinus (MMC).

METHODS

Thirty patients (≥ 18 years) with unilateral MMC who underwent paranasal sinus CT (PNsCT) were included in this single-center retrospective study. Non-MMC sinus was used as the control group. Cyst and air volume of the maxillary sinuses, diameter, and 2-dimensional area of the ostium of the patients were calculated in the 3-dimensional volumetric analysis program. Both correlation and linear regression model analyses were performed for the relationship between MMC and SOA.

RESULTS

Thirty patients were included (mean age of 42.30 ± 17.62 years). A total of 15/30 (50%) were male. The mean SOA in patients with MMC (8.91 ± 1.10 mm2) was lower than in patients without MMC (12.94 ± 1.35 mm2), which was statistically significant (p < 0.001). The mean sinus ostium diameter in patients with MMC (2.12 ± 0.71 mm) was higher than in patients without MMC (1.91 ± 0.82 mm), which was statistically insignificant (p = 0.295). There was a statistically significant, good level of negative linear correlation between SOA and total cyst volume (TCV) [correlation coefficient (r) = - 0.680, p < 0.001]). As a result, the regression model consisting of "Age, Sinus air volume, and TCV" variables is a good model and has statistically significant relations with SOA.

CONCLUSION

In conclusion, small SOAs contribute to the development of MMC. There was a negative correlation between SOA and TCV. In addition, 2D area measurement may be a more accurate method instead of diameter measurement.

Treatment of Mucous Retention Cyst in Association with Sinus Lift and Implant Placement: A Case Report with 1-Year Follow-Up

Sinus lift augmentation techniques, lateral or crestal approaches, have been well documented, with bone substitute graft, or without bone material, with immediate or delayed implant placement as a treatment option for the atrophic maxilla in the posterior area. However, the sinus lift procedures performed in the presence of cysts, mucoceles, mucous retention cysts (MRCs), and antral pseudo-cysts could mainly decrease the sinus cavity volume and could increase the possibility of ostium obstruction and might lead to infection followed by failure of the grafting procedure. A radiological assessment should be made with computerized tomography (CT) or cone-beam CT to evaluate the remaining bone volume and to detect any pathology in the sinus. Different techniques were described in the literature for sinus lifting and bone grafting in patients with cysts. For some authors, cysts should be treated before sinus grafting and six months later, the procedure could be performed. For others, sinus lifting can be performed without lesion removal. At this time, controversy exists regarding the decision on whether lesions must be removed/aspirated or not before sinus grafting. In this study, we report a case where an MRC was aspirated and instantaneously, the sinus membrane was lifted and grafted, and implants were installed with 1-year follow-up after loading. Identifying lesions in the maxillary sinus is essential before planning any type of sinus augmentation and implant placement.

Endodontic Surgery of the Palatal Root of a Maxillary Molar Associated with Simultaneous Management of a Maxillary Sinus Lesion

This case report describes a particular application of endodontic microsurgery with a palatal approach in the presence of a radiopaque lesion inside the maxillary sinus. The patient presented complaining of pain related to the first maxillary molar and events of nasal obstruction and facial pain in the cheek and nasal area. The endodontic orthograde treatment and retreatment were done, respectively, 7 and 4 years earlier. The cone-beam computed tomography (CBCT) scan taken before the treatment showed two separate lesions: one associated with the palatine root of the molar and another one inside the maxillary sinus. The patient agreed to solve both problems in one surgical step: endodontic surgery of the palatine root with palatal access with the simultaneous asportation of a lesion from the maxillary sinus floor. Complete bone healing of the periapical area and the maxillary sinus was visualized on intra-oral radiographs, and CBCT was taken one year after the treatment. As far as the authors know, no one in literature has ever described this approach and solved in such a conservative way both the problems at the tooth and in the maxillary sinus.

Maxillary Antral Pseudocyst Drift after Osteotome Sinus Floor Elevation with Simultaneous Implant Placement: A Case Report and Literature Review

This report describes maxillary antral pseudocyst drift after maxillary sinus floor augmentation through osteotome sinus floor elevation with simultaneous implant placement. 3D Slicer was used to measure the pseudocyst and maxilla for the placement of the implants; follow-up visits were scheduled at 6, 12, and 22 months. No adverse effects were observed during or after surgery, and all implants exhibited osseointegration without mobility. At 6 months after surgery, the pseudocyst had moved posterolaterally from the preoperative position near the anterior medial maxillary sinus, then returned to its original position at 12 months. However, it had remigrated to the posterolateral position at 22 months. The preoperative volume of the pseudocyst was 3.795 mm³; it was 2.370, 3.439, and 2.930 mm³ at 6, 12, and 22 months after surgery, respectively. The changes in pseudocyst drift and volume did not have a substantial negative influence on the implants, presumably because of cystic attachment and the recurrence of multiple pseudocysts at different locations. The risks associated with changes in a pseudocyst can be avoided, if an appropriate treatment plan is selected.

MORPHOLOGICAL FEATURES OF MAXILLARY SINUS CYSTS BASED ON THE STUDY OF PARTICULAR HISTOCHEMICAL AND IMMUNOHISTOCHEMICAL FACTORS OF INFLAMMATION

OBJECTIVE

The aim: To study the morphological structure and immunohistochemical markers of inflammatory cells in the maxillary sinus cyst wall.

PATIENTS AND METHODS

Materials and methods: Biopsy samples of maxillary sinus cysts of 92 operated patients aged 18 to 74 years were studied. We used standard staining with hematoxylin and eosin, PAS reaction, and immunohistochemical analysis with monoclonal antibodies to CD68 (macrophages) and CD3 (T- lymphocytes) to determine morphological features and severity of inflammation and PanCK AE1/AE2 antibodies to identify epithelium state.

RESULTS

Results: All patients were divided into 2 groups: 29 patients with retention cysts and 63 with lymphagiotatic cysts (pseudocysts), depending on the unilateral or bilateral epithelial lining of the cyst wall. Retention cysts had the bilateral epithelial lining with a saving its function and structure. The thinned connective tissue layer was filled with separate clusters of lymphocytes and macrophages. Lymphagiotatic cysts were characterized by the unilateral epithelium lining of the wall with signs of degeneration, desquamation, and loss of the mucus-forming function. Dense infiltration of the connective tissue layer by inflammatory cells with pronounced expression is observed.

CONCLUSION

Conclusions: Immunohistochemical analysis with monoclonal antibodies to CD3 and CD68 demonstrated that the inflammatory infiltrate of pseudocysts is represented by T-lymphocytes and different sizes of macrophages. The inflammatory infiltration of the pseudocyst wall was significantly severe compared to retention cysts.

Maxillary sinus floor augmentation comparing removing versus retaining antral pseudocyst: A retrospective cohort study

OBJECTIVES

To retrospectively compare multilevel volumetric changes in both hard and soft tissues between antral pseudocyst (AP) removal and retainment before maxillary sinus floor augmentation (MSFA) and immediate implant placement.

MATERIAL AND METHODS

Twenty-six patients with thirty-eight implants placed from 2016 to 2021 were included and divided according to a cohort design as follows: 13 removing the cyst (RC group) and 13 "leaving alone" the cyst (LC group). 3D radiographic parameters (primary outcome), 2D parameters and clinical records (secondary outcome) involving both hard and soft tissues were evaluated for 4 periods (T1: immediate postoperative, T2: 6-month, T3: 12-month, and T4: 2- to 5- year follow-up). Possible confounding factors, including sinus anatomical features and implant distribution, were also analyzed to eliminate their disturbance.

RESULTS

The 3D volumetric change rate of bone grafts in the RC group (-9.32 ± 10.01%) from T2 to T3 was significantly lower than that in the LC group (-19.8 ± 10.59%) (p < .05). The change rate of apical bone height (ABH), endo-sinus bone gain (ESBG) and other 2D parameters were not significantly different between the two groups. 5.3% implants in RC group and 9.1% implants failed during follow-ups. 0% postoperative complications were observed in RC group. The Schneiderian membrane of RC group was significantly thinner than that of LC group at two measuring points in sinus.

CONCLUSION

The present study demonstrated that compared to AP retainment, AP removal before MSFA and immediate implant placement can obtain higher bone graft volumetric stability and favorable prognosis. The study protocol was approved by the Medical Ethics Committee of the Affiliated Hospital of Stomatology, School of medicine, Zhejiang University, China (Acceptance number: 2021-117(R)).

Evaluation of Mucous Retention Cyst Prevalence on Digital Panoramic Radiographs in the Local Population of Iran

Introduction. Inflammatory diseases and cysts such as mucous retention cysts (MRCs) and benign tumors include a large proportion of lesions of the mouth, teeth, and jaw. The most common complication of this lesion is sinusitis. Due to the high frequency of these cysts in panoramic radiography of patients referred to dentistry, this study aimed to evaluate the frequency of mucous retention cysts in the maxillary sinus on panoramic images of the local population in Birjand in the year 2020. Methods. In this descriptive research design study, 1624 digital panoramic radiographs of patients referred to the oral and maxillofacial radiology department of Birjand Dental School were selected randomly. Cases were evaluated in terms of MRC appearance by two oral and maxillofacial radiology specialists. Then, based on sex, location, and size of the cysts, the images were assessed. In the predesigned checklists, data were recorded. The MRC diagnosis was confirmed by observation of a dome-shaped radiopaque view on the floor or sinus walls with a smooth surface with no cortical margin. MRCs were categorized into one of three groups by size: 1- less than 10 mm, 2- between 10 and 20 mm, and 3- more than 20 mm. Bilateral or unilateral involvement of lesions was noted. Seasons of the year ( $P<0.05$ ). There was no significant relationship between the month of the year and the prevalence of cysts ( $P>0.05$ ). Results. MRCs were detected in 80 panoramic images of 1624 (9/4), of which 54 patients (67.5%) were male and 26 patients (32.5%) were female. Of those 34 (42.5%), the total cases were between 30 and 40 years old. Most cysts (58.8%) were in the right sinus, and their size was 10–20 mm mainly (43.4%). Based on the results, there was a significant relationship between the prevalence of MRCs with age and sex. Conclusions. Panoramic images are so helpful in MRC detection. In this study, the frequency of MRCs is the highest in males between 30 and 40 years old. These lesions are reported mainly as unilateral and solitary in spring.

Proposal for a Paradigm Shift in Personalized Medicine for Patients with a Maxillary Edentulous Jaw by ENT Specialist and Dentist Cooperation

With the spread of oral implant therapy, serious medical complications related to implant surgery are becoming a social problem. Although the number of complications after implant surgery in the edentulous jaw is decreasing in Japan, maxillary-sinus-related complications (MSRCs) have reached the highest number since 2012. It is essential to identify and eliminate possible predisposing risk factors for MSRCs at an early stage to prevent MSRCs. In this review article, we highlight the causal factors of postoperative complications with or without sinus augmentation for the maxillary molar region to achieve optimal treatment outcomes and reduce complications. In particular, we focus on anatomical variations that can cause the impairment of maxillary sinus drainage. Furthermore, we emphasize that the paradigm for personalized medicine for patients with a maxillary edentulous jaw by ENT specialist and dentist cooperation is shifting from the traditional assessment of maxillary sinus pathologies alone to the new assessment of anatomic variations that can cause the impairment of maxillary sinus drainage in addition to maxillary sinus pathologies.

Odontogenic Maxillary Sinusopathies: a Radiological Classification

Purpose

Before implant surgery, a preoperative radiological evaluation is recommended for recognizing maxillary inflammatory conditions. In order to avoid a failure of the dental procedure and prevent medical-legal consequences, it is necessary to treat patients suffering of maxillary sinus pathologies. The classification proposed in our study aims to standardize the reference values for mucosal thickening and to verify their association with the odontogenic or disventilatory causes of sinus pathology.

Methods

The maximum mucosal thickness was measured at the level of the maxillary sinus floor: mucosal thickness was present when greater than 1 mm and was classified according to its extension within the sinus cavity.

Results

Imaging data of 270 adult patients were included, performed for dental diagnosis and treatment planning, and they were divided into four main classes: Class I (85 pt.), mucosal thickness lesser than 2 mm, not pathological. Class II A (52 pt.), mucosal thickness between 2 and 5 mm, localized to the maxillary sinus floor: it is still considered non-pathological, and a "wait-and-see" approach is recommended. Class II B (46 pt.), mucosal thickness greater than 5 mm but localized at sinus floor: pathological mucosa with odontogenic etiology, requiring dental treatment. Class III A (39 pt.), mucosa thicker than 5 mm and concentric, most likely due to sinus ventilation disfunction: it requires maxillary antrostomy. Class III B (30 pt.), sinonasal manifestations such as nasal polyposis, retention cysts, mucocele, dental foreign body: pathological mucosa to be treated with ESS. Class IV (12 pt.), oroantral fistula: nasal endoscopic or oral approach.

Conclusions

Our classification intends to suggest the better therapeutic option, in case of sinus pathology, according to the entity and pathogenesis of the mucosal thickening, in order to reduce complication and failure rate of dental surgery.

Role of matrix metalloproteinases and their tissue inhibitors in the pathological mechanisms underlying maxillofacial cystic lesions

Cystic lesions are considered to be one of the most common pathologies of the maxillofacial region, and matrix metalloproteinases (MMPs) may represent potential etiological factors. The aim of the present study was to elucidate the role of MMP-2 and MMP-9, and their endogenous tissue inhibitors, tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2, respectively, in the pathogenesis of maxillofacial cystic lesions. A total of 25 patients diagnosed with radicular cysts (RCs; n=20), dentigerous cysts (n=3) and retention cysts (RtCs; n=7) were enrolled in the present study. Gelatin zymography was performed to assess the gelatinolytic activity of MMP-2 and MMP-9, and commercial ELISA kits were used to determine TIMP-1 and TIMP-2 concentrations. Gelatin zymography revealed the presence of both MMP-2 and MMP-9 in all types of samples analyzed. An increase in MMP-9 activity, TIMP-1 concentration and MMP-9/TIMP-1 ratio was observed in the fluid obtained from RCs compared with that obtained from RtCs. In conclusion, MMP-9 may be involved in the pathogenesis of RCs, whereas the activity of MMP-2 in the wall of RtCs was low, and this gelatinase did not appear to significantly affect the development of this type of lesion.

Are mucous retention cysts and pseudocysts in the maxillary sinus a risk factor for dental implants? A systematic review

Background

Mucous retention cysts and pseudocysts of the maxillary sinus are benign lesions present in up to 13% of adult patients. Different surgical approaches for sinus lift and dental implant placement in the presence of these lesions have been proposed.

Material and Methods

A systematic review was performed following the PRISMA statement recommendations to answer the PICO question: Does the aspiration or removal of mucous retention cysts/pseudocysts before or during sinus lifting and dental implant placing, affect the survival of the implants? The study was pre-registered in PROSPERO (CRD42020185528). Included articles quality was assessed using the “NIH quality assessment tool” and “The Newcastle-Ottawa scale”.

Results

Previous literature in this field is scarce and with a low level of evidence. There are no randomized prospective studies. Only 19 studies were identified, being composed of 2 cohort studies and 17 case series/reports. These studies involved 182 patients with a previous history of mucous retention cyst or pseudocyst in 195 maxillary sinuses where 233 implants were placed. The mean age of the patients was 45.5 (range: 12-80 years); 122 (67%) were male patients and 60 (33%) were female patients. The mean follow-up of the patients was 17.6 (range: 4-90 months). Only two fail was reported. No differences were identified in relation to the surgical approach or in relation to the removal/aspiration of the sinus lesion (prior to or simultaneous to sinus grafting) or not.

Conclusions

The level of evidence was grade 4 according to the CEBM and further studies are needed to confirm this observations, but with the available data, dental implants placement after sinus lift procedure in patients with mucous retention cysts and pseudocysts seems to be safe and present high survival regardless on the removal of the lesion or not.

Key words:Dental implants, maxillary sinus, sinus lift, mucous retention cyst, pseudocyst.

[Unilateral diseases of the maxillary sinus]

Unilateral diseases of the maxillary sinus are among the most common rhinologic diagnoses. The diversity of these diseases can represent a challenge for the treating physician. The spectrum ranges from harmless maxillary sinus cysts that seldom require treatment, to highly aggressive malignant tumors. Special attention should be given to the management of inverted papilloma. These benign tumors are characterized by high recurrence rates and the potential for malignant transformation. The key to minimizing recurrence is precise surgical intervention. Other unilateral maxillary sinus diseases such as the antrochoanal polyp and the fungus ball (aspergilloma) are also discussed in depth.

French Otorhinolaryngology Society (SFORL) good practice guidelines for dental implant surgery close to the maxillary sinus

OBJECTIVES

To draw up guidelines for ENT management associated with dental implant surgery with or without sinus lift.

MATERIALS AND METHODS

The methodology followed the rules of laid down by the French Health Authority (HAS): "Methodological bases for drawing up professional recommendations by formalized consensus". The chosen method was the RAND/UCLA "RAND appropriateness method" (short version).

RESULTS

In the pre-implantation check-up, it is recommended to systematically screen for sinonasal pathology on medical interview and to favor 3D CT or cone-beam imaging. It is recommended that imaging include the entire maxillary sinus when the patient does not have sinonasal history or functional signs on interview. Otherwise, examination of all sinonasal cavities is recommended. This attitude enables simultaneous analysis of maxillary infrastructure for pre-implantation work-up and assessment of sinonasal cavity status. Sinus mucosal incidentalomas are very common in the healthy population and must be assessed with reference to the clinical, endoscopic and radiological context.

CONCLUSION

This formalized expert consensus establishes a common base of knowledge, to clarify the issues and clinical situations and to standardize practices.

[Imaging classification diagnosis and maxillary sinus floor augmentation of maxillary sinus cystic lesions]

Maxillary sinus cystic lesions can often be found in cone-beam computed tomography (CBCT) images. However, whether this change affects the implementation of maxillary sinus floor augmentation remains unclear. Combining the common cystic change performance of CBCT, image classification diagnosis of maxillary sinus cystic change was introduced, and the indications and surgical methods of maxillary sinus floor augmentation and postoperative radiographic changes of mucous were analyzed. This procedure may help clinicians evaluate the feasibility and methods of maxillary sinus augmentation in maxillary sinus cystic changes.

Cysts and Pseudocysts of the Oral Cavity: Revision of the Literature and a New Proposed Classification

This article includes a comprehensive and up-to-date review on the cysts of the oral cavity. Several classifications of odontogenic (OC) and non-odontogenic (non-OC) oral cysts and the surrounding regions have been proposed. We suggest a new critical classification based on an established relationship between anatomical area, histological origin and clinical behavior (frequency, rate of recurrence, malignant potential). Moreover, the differential cytokeratin (CKs) expression of the various cysts is reported as epithelium-specific markers of differential diagnosis. Finally, issues related to differential diagnosis and therapeutic approaches of the cysts included in the two groups are described.

Investigation of flow characteristics in the maxillary sinus where polypoid changes develop

Flow behavior in the maxillary sinus where polypoid changes develop was investigated using computational fluid dynamics. A nasal cavity model was constructed, after performing a virtual polypectomy based on computed tomography images of a patient, using a computer-aided design software to artificially remove polypoid changes inside the maxillary sinus. Local flow characteristics in the maxillary sinus were examined for one full respiration period. The results showed that the epithelial surfaces where polypoid changes occur are located in the lower part of the maxillary sinus which contains a protruding zone of the sinus and are characterized by stagnation of air during the entire respiration period. Due to the geometric characteristics, a very slow recirculating motion was found to occur in the bulging area for approximately half of the respiration period as a result of interaction with a larger-scale, counter-rotating vortex filling the middle of the maxillary sinus. With a much smaller velocity inside the maxillary sinus compared to that typically found in the airway passage through the middle meatus, both wall shear and pressure changes were found to be vanishingly small along the epithelial surface of the maxillary sinus where polypoid changes were found.

Diffusion-Weighted Magnetic Resonance Imaging in Maxillary Sinuses Inflammatory Diseases: Report of Three Cases and Literature Review

Background

Magnetic resonance imaging is considered a preferable imaging examination in the diagnosis of inflammatory maxillary sinus disease and can provide precise sinonasal characterization. Diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient are complementary magnetic resonance imaging tools that can be applied to the differentiation of sinus diseases. In this report, 3 cases of inflammatory maxillary sinus diseases imaging findings considering diffusion-weighted magnetic resonance imaging features were described. Additionally, a literature review considering the use of diffusion-weighted magnetic resonance imaging in inflammatory lesions is provided.

Methods

The cases reported were: presence of air-fluid levels, mucosal thickening and a mucous retention cyst. Conventional magnetic resonance imaging and apparent diffusion coefficient (ADC) maps, with ADC values were demonstrated. In the literature review, the studies considering inflammatory lesions were detailed, as well as ADC values established by investigators.

Results

ADC values for presence of air-fluid levels, mucosal thickening and mucous retention cyst were respectively: 1.99 x 10^-3 mm²/s; 1.83 x 10^-3 mm²/s; 2.05 x 10^-3 mm²/s.

Conclusions

It was observed that apparent diffusion coefficient values from the inflammatory lesions described in this report were different and apparent diffusion coefficient may be useful in the differentiation of these maxillary sinus alterations. Further larger sample investigations considering apparent diffusion coefficient values focusing in inflammatory lesions are recommended. The lack of studies considering the use of diffusion-weighted magnetic resonance imaging on inflammatory diseases diagnostic was the major limitation to the literature review.

Posterior translacrimal approach to the maxillary sinus

Background:

This study aimed to compare the view into the maxillary sinus using the posterior translacrimal approach compared with grade 3 antrostomy.

Methods:

Grade 3 antrostomy followed by a posterior translacrimal approach was performed on four cadavers. The maximum intramaxillary view was documented endoscopically guided by electromagnetic navigation. Representative screenshots were evaluated in a blinded manner by three independent sinus surgeons. In addition, a prospective investigation of specific complications in the post-operative course of consecutive patients was performed.

Results:

In the cadaver study, the posterior translacrimal approach provided a significantly better view into the maxillary sinus compared with grade 3 antrostomy. In the clinical study, only 1 out of 20 patients reported on a minor problem with lacrimal drainage at 6 months.

Conclusion:

The posterior translacrimal approach to visualising the maxillary sinus should be considered a strong alternative to more radical techniques.

Incidental paranasal sinusitis on routine brain magnetic resonance scans: association with atherosclerosis

BACKGROUND

Incidental paranasal sinusitis (IPS) is common on imaging for non-sinusitis disorders, usually without symptoms or obstructive features, and possibly arising from periodontitis (PD). PD associations with atherosclerosis have been widely reported. We test if IPS may also be associated with atherosclerosis.

METHODS

IPS was scored retrospectively in a random sample of 180 magnetic resonance (MR) brain scans and compared with chart review for atherosclerosis (all subtypes), rhinosinusitis, and related factors (smoking, asthma, and relevant surgery). IPS was scored out of 30, from all sinuses, with maxillary sinuses weighted double volumetrically. Significant IPS (Sig IPS) was designated as 6 or more out of 30. Bivariate logistic regression was used to test for associations of Sig IPS to the clinical data, with multivariate analysis then testing for potential confounders.

RESULTS

A total of 173 subjects were analyzed (7 exclusions). MR indications included suspected acute/prior stroke (22.0%). Sig IPS found in 20 (11.6%). Positive histories for atherosclerosis were cerebral, 57 (32.9%); coronary, 48 (27.7%); and peripheral arterial disease, 14 (8.1%). IPS ≥6 was strongly associated with cerebrovascular disease (odds ratio [OR] 6.0, p < 0.001), and less robustly to smoking (OR 2.9, p = 0.07) and rhinosinusitis (OR 2.4, p = 0.09). No associations with coronary or peripheral artery diseases were found. After controlling for smoking and rhinosinusitis, yielding significant subclinical sinusitis, the link of Sig IPS to cerebrovascular disease persisted (modified OR 5.2, p = 0.002).

CONCLUSION

Significant incidental sinusitis, which is mostly subclinical sinusitis, is associated with cerebrovascular disease but not other atheroscleroses. This suggests possible common causation of both by PD.

Comprehensive review on endonasal endoscopic sinus surgery

Endonasal endoscopic sinus surgery is the standard procedure for surgery of most paranasal sinus diseases. Appropriate frame conditions provided, the respective procedures are safe and successful. These prerequisites encompass appropriate technical equipment, anatomical oriented surgical technique, proper patient selection, and individually adapted extent of surgery. The range of endonasal sinus operations has dramatically increased during the last 20 years and reaches from partial uncinectomy to pansinus surgery with extended surgery of the frontal (Draf type III), maxillary (grade 3-4, medial maxillectomy, prelacrimal approach) and sphenoid sinus. In addition there are operations outside and beyond the paranasal sinuses. The development of surgical technique is still constantly evolving. This article gives a comprehensive review on the most recent state of the art in endoscopic sinus surgery according to the literature with the following aspects: principles and fundamentals, surgical techniques, indications, outcome, postoperative care, nasal packing and stents, technical equipment.

Cyst decreased in size post maxillary sinus floor augmentation surgery in diabetic patient: A case report

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2.37 mm from the ridge to sinus floor with cyst (18.72 mm × 24.61 mm) firmly attached to the wall.

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Lateral approach to elevate the sinus floor with cyst simultaneously in diabetic patient.

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Osseointegration was achieved and the cyst decreased in size 6 months later.

Introduction

Whether mucosal cyst of maxillary sinus is contraindication for sinus floor augmentation surgery has been a controversial hot spot for years.

Presentation of case

This case aims to present the surgical procedure of sinus floor augmentation surgery with cyst (18.72 mm × 24.61 mm) in diabetic patient. And 6 months later, the cyst decreased in size. The authors elevated the sinus floor and cyst simultaneously. The surgery was carried out successfully without sinus membrane perforation and the alveolar ridge gained about 8 mm height. Six months later, the cyst decreased in size and osseointegration was observed.

Discussion

Interdisciplinary cooperation is encouraged to diagnose benign mucosal cyst. The isolation between sinus lumen and the grafted sub-sinus space is important. Graft contamination or dispersion into the sinus lumen should be avoided. The integrity of the sinus membrane and use of antibiotics are very important to prevent the occurrence of postoperative sinus infection

Conclusion

The authors conclude that sinus augmentation surgery could be done with mucosal cyst in diabetic patient.

Longitudinal response of membrane thickness and ostium patency following sinus floor elevation: a prospective cohort study

OBJECTIVES

To investigate the influence of sinus floor elevation (SFE) on sinus physiology, including Schneiderian membrane thickness (MT) and ostium patency, using cone beam computed tomography (CBCT).

MATERIALS AND METHODS

Based on pre-established selection criteria, 53 patients in combination with 53 sinuses were referred for SFE with a lateral approach using deproteinized bone mineral. CBCT was performed prior to, immediately after surgery and before staged implant placement. The Schneiderian MT of the elevated region, ostium patency, and other clinical data was evaluated.

RESULTS

The two-stage sinus augmentation technique was applied in 33 males and 20 females. Four membrane perforations were observed during the surgical procedure. The Schneiderian membrane exhibited significant swelling immediately after augmentation (P < 0.0001), but this difference disappeared after a mean healing period of 7.51 months. The corresponding changes were also observed for ostium patency with a tendency of transient obstruction after surgery. Sinuses with flat mucosal thickening or pseudocysts did not present a liability of perforation compared to the normal cases, and the augmentation procedure was not likely to deteriorate the pathology of mucosal thickening or pseudocysts.

CONCLUSIONS

The results show that SFE with a lateral approach has no significant influence on MT and ostium patency after the healing period except for postoperative transient swelling and obstruction. Thickened membranes and antral pseudocysts in a small size might not be contraindications to SFE from the standpoint of the surgical impact on the Schneiderian membrane.

Sinus grafting and simultaneous removal of large antral pseudocysts of the maxillary sinus with a micro-invasive intraoral access

Large antral pseudocysts of the maxillary sinus (APCs) may hamper the elevation of the Schneiderian membrane during sinus grafting and may impair osteo-meatal complex patency after sinus augmentation. Therefore, these should be removed prior to or at the time of sinus grafting. This study presents a new technique that combines enucleation of large APCs during sinus grafting via a lateral approach with preservation of the Schneiderian membrane periosteal layer. Twelve patients underwent a sinus graft via lateral approach during the years 2004-2012. Simultaneous APC removal was achieved through a small additional bony access, preserving the integrity of the periosteal layer of the Schneiderian membrane. Nineteen implants were inserted at the time of sinus augmentation or during a second stage. Prosthetic rehabilitation was started at 4-6 months after implant placement. No patient developed surgical complications or APC recurrence. The survival rate of implants and related prostheses was 100% over a mean follow-up of 50 months (range 12-96 months) after completion of the prosthetic restorations. This technique may represent an effective procedure to achieve APC removal at the time of sinus grafting, preserving the integrity of the Schneiderian membrane periosteal layer.