The optimal timing of functional endoscopic sinus surgery for odontogenic infections precipitated by retention cysts of the maxillary sinus was investigated.

Five adults who underwent functional endoscopic sinus surgery were examined.

The root apexes of all teeth that had odontogenic infection protruded into the maxillary sinus. All teeth with odontogenic infections precipitated by the retention cysts had percussion pain, indicating they had periodontitis and pulpitis around the root apex. They were vital teeth, indicating they did not have pulp necrosis. The small area of cyst wall attached to the floor of the maxillary sinus and root apex were left intact. The teeth that had odontogenic infections precipitated by retention cysts continued to be vital with no symptoms.

Functional endoscopic sinus surgery should be performed before periodontitis and pulpitis of the root apex progress to ascending pulpitis and pulp necrosis. In other words, functional endoscopic sinus surgery should be performed while the affected tooth is still vital.

Unilateral maxillary sinus opacification on computed tomography may reflect an inflammatory or neoplastic process. The neoplasia risk is not clear in the literature.

In this retrospective study, computed tomography sinus scans performed over 12 months were screened for unilateral maxillary sinus opacification, and the rates of inflammatory and neoplastic diagnoses were calculated.

Of 641 computed tomography sinus scans, the rate of unilateral maxillary sinus opacification was 9 per cent. Fifty-two cases were analysed. The risk of neoplasia was 2 per cent (inverted papilloma, n = 1). No cases of unilateral maxillary sinus opacification represented malignancy, but one case of lymphoma had an incidental finding of unilateral maxillary sinus opacification on the contralateral side. Patients with an antrochoanal polyp (n = 3), fungal disease (n = 1), inverted papilloma and lymphoma all had a unilateral nasal mass.

Our neoplasia rate of 2 per cent was lower than previously reported. A unilateral mass was predictive of pathology that required operative management. Clinical findings, rather than simple findings of opacification on computed tomography, should drive the decision to perform biopsy.

To review the clinical characteristics, prevalence and outcomes of chronic rhinosinusitis patients with a hypoplastic maxillary sinus who underwent functional endoscopic sinus surgery.

A retrospective review was performed for the 814 consecutive, elective functional endoscopic sinus surgery procedures performed at an academic centre from 2010 to 2020, to identify patients with a hypoplastic maxillary sinus.

A total of 56 hypoplastic maxillary sinus cases were detected. Maxillary sinus hypoplasia presented unilaterally in 20 cases and bilaterally in 18 cases. Of the maxillary sinus hypoplasia cases, 38 were type I, 17 were type II and 1 was type III. The average Lund–McKay score was 8.6. No major post-operative complications were reported. Four patients had minor complications and one had persistent post-nasal drip.

Functional endoscopic sinus surgery is a safe and effective procedure for improving the clinical condition of patients with a hypoplastic maxillary sinus; however, careful pre-operative radiological evaluation, identification of intra-operative endoscopic landmarks and use of additional techniques may be essential to achieve satisfactory results and avoid possible serious complications.

Chronic maxillary atelectasis is an infrequent entity and data on its prevalence are lacking. This study investigated the prevalence of chronic maxillary atelectasis and aimed to determine the bilaterality of this entity.

The data for 5835 patients who underwent paranasal sinus computed tomography from 2016 to 2020 were retrospectively analysed.

Fifty-four patients were diagnosed with chronic maxillary atelectasis; its prevalence was 0.92 per cent. The mean age of these 54 patients was 42.98 ± 18.89 years (range, 18–85 years); 17 of the patients were female and 37 were male. Chronic maxillary atelectasis was unilateral in 42 patients and bilateral in 12 patients (22.2 per cent). Eight patients were found to have enophthalmos with apparent facial asymmetry.

The prevalence of bilateral chronic maxillary atelectasis may be higher than previously reported and bilaterality may increase as the number of diagnosed cases increases. A unified classification is also proposed, which describes the silent sinus syndrome as chronic maxillary atelectasis IIIS.

Congenital midnasal stenosis has previously been described as a cause of nasal obstruction in infants, and conservative and interventional treatments have been suggested. However, midnasal stenosis in adults has not been reported and related normative measurements have not been studied.

Three adult patients presented with nasal obstruction and, based on examination and radiological findings, were diagnosed with midnasal stenosis. Anatomical measurements were studied in axial and coronal computed tomography scans, and compared with findings for 161 healthy individuals.

Anatomical measurements showed that the endonasal cavity was larger in males than females. The midnasal region was found to be constricted in patients compared to healthy controls.

This is the first study to report on midnasal stenosis in adults and to define normative anatomical measurements in adults. In patients presenting with nasal obstruction, midnasal stenosis should be suspected during endoscopic visualisation of medially located middle turbinates and uncinate processes in nasal cavities. A definitive diagnosis of midnasal stenosis can be made by examining paranasal sinus computed tomography scans. Endoscopic middle turbinectomy, complete uncinectomy, mega maxillary antrostomy and partial anterior ethmoidectomy have been suggested to relieve midnasal stenosis.

Odontogenic sinusitis is a common cause of rhinosinusitis that is often undiagnosed and overlooked. No single sign or symptom is specific for odontogenic sinusitis, and failure to focus on the specific radiological features can delay diagnosis.

This paper presents four cases of chronic sinusitis that had an odontogenic origin. Each case was referred for a second opinion. Three patients had previously undergone unsuccessful surgical management.

The literature, and the associated contributory clinical, radiological and microbiological features required for correct diagnosis and management, are reviewed.

Each case resulted in a positive patient outcome following the involvement of both otolaryngology and maxillofacial surgery departments.

A high index of suspicion is advocated for odontogenic sinusitis in cases not responding to standard management plans. Collaboration with a maxillofacial specialist is important for diagnosis and management. This should be considered where standard management fails, or clinical features and radiological signs of odontogenic sinusitis are present. This paper also highlights the need for otolaryngologists to incorporate, at the very least, a basic dental history and examination as part of their assessment in recalcitrant cases.

Odontogenic sinusitis is an underdiagnosed entity and is one cause of failure of conventional treatments of sinusitis. Unfortunately, there is no consensus so far on the best management protocol. This retrospective study aimed to suggest a practical management protocol that can reduce misdiagnosis and improve treatment outcomes.

The study included 74 patients with confirmed odontogenic sinusitis who were diagnosed and treated over 10 years (2010–2019). The patient data were recorded and analysed.

Dental pain was reported in only 31.1 per cent of patients. Fifty-six patients (75.7 per cent) had received dental treatment during the last year, but only 13 (23.1 per cent) reported it. Dental pathology was missed on initial computed tomography evaluation in 24 patients (32.4 per cent). Forty-one patients (55.4 per cent) were successfully treated by dental procedures and antibiotics. Fourteen patients needed functional endoscopic sinus surgery in addition to dental procedures.

Successful management of odontogenic sinusitis requires good communication between rhinologists, radiologists and dentists. Dental treatment should be the logical first step in the treatment protocol, unless otherwise indicated.

For recalcitrant chronic maxillary sinusitis, modified endoscopic medial maxillectomy has been shown to be clinically beneficial after failed maxillary antrostomy as endoscopic medial maxillectomy may offer improved topical therapy delivery. This study compared irrigation patterns after maxillary antrostomy versus endoscopic medial maxillectomy, using computational fluid dynamic modelling.

A 54-year-old female with left chronic maxillary sinusitis underwent maxillary antrostomy, followed by endoscopic medial maxillectomy. Computational fluid dynamic models were created after each surgery and used to simulate irrigations.

After maxillary antrostomy, irrigation penetrated the maxillary sinus at 0.5 seconds, initially contacting the posterior wall. The maxillary sinus was half-filled at 2 seconds, and completely filled at 4 seconds. After endoscopic medial maxillectomy, irrigation penetrated the maxillary sinus at 0.5 seconds and immediately contacted all maxillary sinus walls. The maxillary sinus was completely filled by 2 seconds.

Computational fluid dynamic modelling demonstrated that endoscopic medial maxillectomy allowed faster, more forceful irrigation to all maxillary sinus walls compared with maxillary antrostomy.

This study aimed to assess the outcomes of a prelacrimal recess approach assisted middle meatal antrostomy in the management of hard to reach maxillary sinus pathologies.

Twenty-five patients with maxillary sinus pathology underwent prelacrimal recess approach assisted middle meatal antrostomy (with a prelacrimal recess width of more than 3 mm). Patients were prospectively evaluated using both the Arabic version of the Sino-Nasal Outcome Test-22 and nasal endoscopy at least 6 months post-operatively.

Our study included 25 maxillary sinuses (13 with antrochoanal polyps, 10 with maxillary fungal ball and 2 with a migrated part of a tooth). At a mean follow-up period of 10.9 months, all patients showed significant improvement in total mean Sino-Nasal Outcome Test-22 score. There was recurrence of one case with antrochoanal polyp and two cases with asymptomatic synechia. Injury to the nasolacrimal duct was not reported.

A prelacrimal recess approach assisted middle meatal antrostomy is a reliable and safe technique to manage pathologies in hard to reach regions within the maxillary sinus.

Treatment of inflammatory and neoplastic disease in the maxillary sinus, pterygopalatine and infratemporal fossae requires appropriate surgical exposure. As modern rhinology evolves, so do the techniques available. This paper reviews extended endoscopic approaches to the maxillary sinus and the evidence supporting each technique.

A literature search of the Ovid Medline and PubMed databases was performed using appropriate key words relating to endoscopic approaches to the maxillary sinus.

Mega-antrostomy and medial maxillectomy have a role in the surgical treatment of refractory inflammatory disease and sinonasal neoplasms. The pre-lacrimal fossa approach provides excellent access but can be limited because of anatomical variations. Both the transseptal and endoscopic Denker's approaches were reviewed; these appear to be associated with morbidity, without any significant increase in exposure over the afore-described approaches.

A range of extended endoscopic approaches to the maxillary sinus exist, each with its own anatomical limitations and potential complications.

Transnasal inferior meatal antrostomy is increasingly used for the treatment of post-Caldwell–Luc mucoceles in maxillary sinus. This study aimed to report the outcomes after inferior meatal antrostomy with a mucosal flap for recurrent mucoceles.

The records of patients who had undergone transnasal inferior meatal antrostomy with or without a mucosal flap were reviewed.

Transnasal endoscopic inferior meatal antrostomy with or without a mucosal flap was performed in 21 and 49 patients, respectively. No complications were observed. A closing of the antrostomy was found in 9 (18.4 per cent) of the 49 patients who underwent antrostomy without a mucosal flap. No closings were observed in the 21 patients who underwent antrostomy with a mucosal flap. There was a significant difference in the rate of closing for surgery with and without the mucosal flap.

Transnasal endoscopic inferior meatal antrostomy with a mucosal flap is a safe method for the treatment of post-Caldwell–Luc maxillary mucoceles that effectively prevents recurrence.

Chronic maxillary atelectasis is a rare and underdiagnosed condition in which there is a persistent and progressive decrease in maxillary sinus volume secondary to inward bowing of the antral walls. Chronic maxillary atelectasis is typically unilateral. Simultaneous bilateral chronic maxillary atelectasis is extremely uncommon.

A retrospective review was performed of patient data collected by the senior clinician over a three-year period (2015–2018). A comprehensive literature search was conducted to locate all documented cases of chronic maxillary atelectasis in English-language literature. Abstracts and full-text articles were reviewed.

Three patients presented with sinonasal symptoms. Imaging findings were consistent with bilateral chronic maxillary atelectasis. The literature review revealed at least nine other cases of bilateral chronic maxillary atelectasis. Management is typically via endoscopic middle meatus antrostomy.

Chronic maxillary atelectasis was initially defined as a unilateral disorder, but this description has been challenged by reports of bilateral cases. Further investigation is required to determine the aetiology and pathophysiology of the disease.

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

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.

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.

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

Although organised haematoma often induces bone thinning and destruction similar to malignant diseases, the aetiology of organised haematoma and the optimal treatment remain unclear. This paper presents the clinical features of individuals with organised haematoma, and describes cases in which a novel modified approach was successfully applied for resection of organised haematoma in the maxillary sinus.

Pre-operative examination data were evaluated retrospectively. Modified transnasal endoscopic medial maxillectomy was employed.

Fourteen patients with organised haematoma were treated. Contrast-enhanced computed tomography showed heterogeneous enhancement in all patients. Eight patients underwent modified transnasal endoscopic medial maxillectomy, without complications such as facial numbness, tooth numbness, facial tingling, lacrimation and eye discharge. Dissection of the apertura piriformis and anterior maxillary wall was not necessary for any of these eight patients. No recurrence was observed.

Pre-operative examinations can be helpful in determining the likelihood of organised haematoma. Modified transnasal endoscopic medial maxillectomy appears to be a safe and effective method for organised haematoma resection.

The present study investigates the indications for transnasal endoscopic surgery in treating post-operative maxillary cysts.

In this retrospective study, the records of 118 patients with post-operative maxillary cysts (88 unilateral and 30 bilateral) consisting of 148 procedures were reviewed.

A transnasal endoscopic approach was performed in 144 lesions (97.3 per cent). A combined endonasal endoscopic and canine fossa (external) approach was performed in 4 of 148 lesions, because the cysts were located distant from the nasal cavity and had a thick bony wall. A ventilation stent was placed in four patients (four cysts) to avoid post-operative meatal antrostomy stenosis. Recurrence was observed in five patients (4.2 per cent), all of whom subsequently underwent transnasal endoscopic revision surgery.

Transnasal endoscopic surgery is an effective treatment for post-operative maxillary cyst with the exception of cysts located distant from the nasal cavity.

To describe modification to endoscopic medial maxillectomy for treating extensive Krouse stage II or III inverted papilloma of the nasal and maxillary sinus.

Ten patients with inverted papilloma arising from the nasoantral area underwent diagnostic nasal endoscopy, contrast-enhanced computed tomography scanning of the paranasal sinus and pre-operative biopsy of the nasal mass. They were all managed using endoscopic medial maxillectomy and followed up for seven months to three years without recurrence.

Most patients were aged 41–60 years at presentation, and most were male. Presenting symptoms were nasal obstruction, mass in the nasal cavity and epistaxis. In each case, computed tomography imaging showed a mass involving the nasal cavity and maxillary sinus, with bony remodelling. The endoscopic medial maxillectomy approach was modified by making an incision in the pyriform aperture and removing part of the anterolateral wall of the maxilla bone en bloc.

Modified endoscopic medial maxillectomy providing full access to the maxillary and ethmoid sinuses is described in detail. This effective, reproducible technique is associated with reduced operative time and morbidity.

Maxillary sinus atelectasis is a form of chronic rhinosinusitis of uncertain aetiology. Previously, the conventional treatment for this condition has been standard endoscopic surgery. There are no reports in the literature of successful treatment using balloon sinuplasty.

A case of a patient with right maxillary sinus atelectasis is presented, who was treated using the balloon sinuplasty technique.

The patient's right maxillary sinus atelectasis was successfully treated using balloon sinuplasty. Three-month follow-up evaluation documented retention of the remodelled form of the uncinate process, and of maxillary sinus os patency.

This is the first report of successful use of the balloon sinuplasty technique for the treatment of maxillary sinus atelectasis. Follow up demonstrated resolution of the underlying pathophysiology. Further study of the balloon sinuplasty technique for the treatment of maxillary sinus atelectasis is required to determine whether it has widespread applicability, given the current standard treatment.

This study aimed to examine the feasibility of an endonasal, transmaxillary, transpterygoid approach to the foramen ovale by examining key anatomical, radiological and surgical landmarks.

Measurements were taken from 183 patients' computed tomography scans using BrainLAB iPlan 1.1 Cranial software. Endoscopic dissection was then carried out on a cadaver to assess surgical viability.

We found that the distances from the posterior maxillary wall to the foramen ovale and from the anterior nasal spine to the foramen ovale were statistically significantly larger in men than women. The distance from the base of the lateral pterygoid plate to the foramen ovale, and the angle between the foramen ovale, the anterior nasal spine and the sphenoid rostrum, were constant between the sexes. The importance of the lateral pterygoid plate in locating the foramen ovale was demonstrated.

With the increasing popularity of image guidance and assisted navigation in endoscopic surgery, these findings increase anatomico-radiological understanding of the surgical approach investigated.

Organised haematomas of the maxillary sinus are rare, non-neoplastic, haemorrhagic lesions which can extend into the nasal cavity and/or the other paranasal sinuses. This study aimed to investigate the pathology of maxillary sinus organised haematoma, and also proposes a new aetiological hypothesis based on the observed pathology.

Biopsies, computed tomography, magnetic resonance imaging and post-surgical histopathological examination of resected specimens were carried out.

Distinct pathological differences were observed between the basal and peripheral portions of organised haematomas. We propose that an organised haematoma originates from the exudation of blood components between vascular endothelial cells. As a result, the basal portion consists of aggregated, dilated vessels around the natural ostium of the maxillary sinus. In addition, pseudovessels, without endothelial cells, arise from endocapillary vessels within the haematoma. Exudation of additional blood components from the pseudovessels advances the growth of the organised haematoma.

To report a patient with maxillary pneumosinus dilatans and facial deformity treated by reduction osteoplasty and reconstruction.

This study describes the successful management of facial deformity in a 17-year-old male with maxillary pneumosinus dilatans. The patient's facial deformity of the maxillary sinus, which had been slowly progressing over a 10-year period, was managed by reduction osteoplasty and reconstruction using the maxillary bone, conchal cartilage and Tutoplast-processed fascia lata via a sublabial approach. This treatment yielded satisfactory functional and aesthetic outcomes.

As pneumosinus dilatans of the maxillary sinus is uncommon, there is no established surgical treatment protocol. This surgical technique was less invasive than other described procedures and revealed good cosmetic results.