Isolated lesions of the sphenoid sinus: features of diagnosis and treatment

Full Text

INTRODUCTION

The spread of radiation (magnetic resonance imaging (MRI), Computed tomography (CT)) and visual (endoscopy) diagnostic methods observed today is responsible for an increase in the number of cases of isolated sphenoiditis [1, 2, 3]. According to the literature, the proportion of isolated sphenoiditis in the general structure of diseases of the paranasal sinuses (PNS) is no more than 5% [4, 5, 6]. However, taking into account the huge number of cases of PNS inflammatory pathology, the absolute figures can be very significant. In the structure of sinusitis, there are increasingly resistant (resistant to treatment) forms, including those of fungal origin [7]. Data on the prevalence of the pathology are very scarce, as sphenoiditis is rarely presented as an independent nosological entity when performing a statistical report in hospitals and clinics. The relatively low prevalence often determines the passive position of specialists in the differential diagnosis of sphenoid sinus (SS) lesions. CT and MRI are the main methods used for the differential diagnosis in this group of patients. The interpretation of the research results is however not always unambiguous and can lead to both the overdiagnosing and, conversely, to the underdiagnosing of sphenoiditis, expressed as an underestimation of the radiation diagnosis data and as an objective presentation, often leading to the development of chronic and complicated forms.

Patients are referred to an ENT doctor only after a long, unsuccessful treatment with specialists of related specialties, and this explains the frequent underdiagnosis of sphenoiditis, and the occurrence of complicated forms [8]. Differential diagnosis of the pathological process in the sinus at the preoperative stage is extremely important, as ill-considered intervention can cause severe and even fatal complications [9, 10].

Approximately, 5%–30% of all isolated lesions of the sphenoid sinus are seen in patients with the non-invasive fungal form [11, 12]. Chronic sphenoiditis is characterized by a latent course, not always diagnosed in the early stages [13, 14]. According to a number of researchers, the frequency of pathological findings in the sphenoid sinus during autopsy of persons, whose lifetime diagnosis of sphenoiditis has not been established, ranges from 10% to 68% [15, 16]. It is very important to study the issues of remodeling in the sphenoid sinus, including the phenomena of osteitis in the fungal forms [17].

Complicated course of isolated sphenoiditis is not uncommon, and the main factor in the development of complications is a delayed diagnosis. However, complications associated with the involvement of the oculomotor nerves in the pathological process, especially pair VI (n. abducens), are the most common [4, 9, 16]. Literature provides cases of invasive, generalized forms of fungal sphenoiditis with the rapid development of ophthalmic, intracranial, and systemic (septic) complications [7, 12, 14].

According to the literature, treatment approaches for isolated lesions of the sphenoid sinus are different. Some authors consider the presence of isolated sphenoiditis, especially fungal forms like mucocele, an absolute indication for surgery, while others start with a conservative therapy in the absence of complications [1, 3, 11, 12]. The surgical treatment in such patients is not only aimed at stopping the inflammatory process, but also at creating the conditions for adequate ventilation of the sinuses, thereby preventing possible relapse. Issues of the differentiated approach to the surgical treatment are insufficiently covered in the scientific literature and are predominantly descriptive.

AIM

The study aimed to analyze cases of isolated lesions of the sphenoid sinuses and to identify the main aspects and errors in the differential diagnosis at the prehospital stage.

MATERIAL AND METHODS

The paper provides data on the treatment of 58 patients with isolated lesions of the sphenoid sinus, who were hospitalized at the N.A. Semashko Nizhny Novgorod Regional Clinical Hospital (Department of Ear, Throat and Nose Diseases of the Privolzhsky Research Medical University of the Ministry of Health of the Russian Federation) during a four years period, from 2015–2018. Their ages ranged between 18 and 68 years. The average age of patients with isolated sphenoiditis was 43 years old; women under 35 were the most concerned. Sex distribution showed 21 (30.7%) men and 37 (69.3%) women. The disease duration was 26 ± 19 days. A total of 118 patients with various forms of damage to the sphenoid sinus were monitored in the clinic during this period with an SS lesion registered as a manifestation of chronic rhinosinusitis (with and without polyps) in 60 patients, meaning there was a combined lesion of several or all of the PNS even though such cases were not included in the study.

Inclusion criteria were X-ray (CT, MRI) signs of a pathological process in the sphenoid sinus, specific and nonspecific symptoms, latent course of sphenoiditis, and absence of a pathological process in other PNS.

Exclusion criteria were combined lesion of other groups of PNS, and nosocomial sphenoiditis.

Conditions such as curvature of the nasal septum, vasomotor/allergic rhinitis, turbinate hypertrophy, conchabullosa of the middle turbinate were not exclusion criteria.

Patients with newly established diagnosis accounted for 85% of the total; recurrent forms of the disease were noted in 15% of cases, including 5 patients after previous surgery (Table 1).

 

Таблица1. Распределение по виду патологического процесса

Table 1. Distribution by the type of pathological process

Morphological form	Number of cases
Polypous process	15 (25.8%)
Cyst	18 (31%)
Mucocele	5 (8.6%)
Fungal sphenoiditis	12 (20.6%)
Invasive fungal sphenoiditis	2 (3.4%)
Meningocele	4 (6.8%)
Neoplasm	2 (3.4%)

 

Upon admission to the hospital, patient examination was performed, including clinical analyzes, consultations of related specialists, namely a neurologist, a neurosurgeon, an ophthalmologist (depending on clinical manifestations). All patients underwent preoperative endorinoscopy. In preparation for surgical treatment, the presence of concomitant diseases in the patient was assessed through the manifestation of symptoms in PNS affecting significantly the course of the pathological process in the nasal cavity like bronchial asthma, aspirin triad, persistent or intermittent allergic rhinitis, as well as a combination of these diseases.

DISCUSSION AND RESULTS

Cephalic syndrome in most cases was the main reason for seeking medical help. All patients with pain syndrome were initially examined by a neurologist or therapist; they underwent an MRI scan at the prehospital stage. In this group (n = 21, 36.2%), 9 patients were referred to an otorhinolaryngologist immediately after receiving MRI data. 12 patients either underwent further conservative treatment by a neurologist or did not receive any treatment, despite the obvious data of MRI studies. After the MRI study, a clarifying CT scan was prescribed for only 3 patients with the rest of patients being referred to the hospital with MRI results. We can therefore suggest within the framework of our study, the prevalence of MRI diagnostics in prehospital examination and the neglect of CT studies by specialists. The symptomatic presentation in the patients studied varied greatly from latent asymptomatic forms to severe cephalic and ophthalmic manifestations. We noted a certain relationship between symptomatic manifestations and the morphological forms of the disease (Table 2).

 

Таблица 2. Симптоматические проявления

Table 2. The symptomatic manifestation

Morphological form	Clinical symptoms
	Headache	Postnasal drip	Dizziness	Nasal obstruction	Orbital symptoms
Polypous/polypous-purulent process	+	+++	-	++	-
Cyst	-	-	-	+	-
Mucocele	++	+	-	+	-
Fungal sphenoiditis	++	++	+	+	+
Invasive fungal sphenoiditis	+++	++	+	+	+++
Meningocele	+	+	+	-	-
Neoplasm	++	+	+	-	+++

«+» – severity of the symptom from + to +++. «-» – absence of symptom.

 

Manifesting rhinological symptoms were generally noted in no more than one third of cases. In other situations, either nonspecific symptoms (cephalgic and/or ophthalmoplegic manifestations) or asymptomatic courses were registered. Latent forms of SS lesions detected accidentally during MRI/CT examination accounted for about 20% of all cases. These lesions were most often in the form of a cyst of the sphenoid sinus and mucocele (Figure 1) and were less often asymptomatic in the fungal form of the lesion and meningocele (Figures 2, 3).

 

Рисунок 1. Мукоцеле клиновидной пазухи.

Figure 1. Mucocele of the sphenoid sinus.

 

Рисунок 2. Грибковый сфеноидит. 2.1 КТ (аксиальный срез); 2.2 Соустье обтурировано полипом. Трансназальный доступ; 2.3 – грибковые массы в пазухе.

Figure 2. Fungal sphenoiditis. 2.1 CT (axial cross-section); 2.2 Anastomosis is obturated by a polyp. Transnasal access; 2.3 – fungal masses in the sinus.

 

Рисунок 3. КТ (фронтальный срез). Остеит стенок клиновидной пазухи при грибковом синусите.

Figure 3. CT (front section). Osteitis of the walls of the sphenoid sinus in fungal sinusitis.

 

Surgery. All patients underwent surgical treatment after a thorough analysis of CT scans conducted to clarify the variant of the sphenoid sinus structure and the presence of anatomical variants of the structure (Onodi cells, digiscence of the canal of the internal carotid artery, optic nerve, etc.) (Figures 4a, 4b).

 

Рисунок 4а. Дигисценция канала внутренней сонной артерии. КТ-исследование.

Figure 4a. Dehiscence of the internal carotid artery channel. CT study

 

Рисунок 4б. Дигисценция канала внутренней сонной артерии. Эндоскопическая картина.

Figure 4b. Dehiscence of the internal carotid artery channel. Endoscopic image.

 

All surgical interventions were performed under general anesthesia. The transnasal, extended transnasal, transethmoid, Bolger Box approaches were the most frequently used although the transpterygoid approach was used in one case (Table 3, Figure 5, 6).

 

Рисунок 5. 5a – грибковое тело латерального кармана клиновидной пазухи (КТ, аксиальный срез); 5b – расширенный трансназальный доступ (700 эндоскоп); 5c – КТ через 6 мес. после операции.

Figure 5. 5a – fungal ball in the lateral "pocket" of the sphenoid sinus (CT, axial section); 5b – extended transnasal access (700 endoscope); 5c – CT in 6 months after operation.

 

Рисунок 6. Менингоцеле клиновидной пазухи. 6a – МРТ (фронтальный срез); 6b – расширенный трансназальный доступ. Пластика ликворного дефекта после удаления менингоцеле (материал – жир).

Figure 6. Meningocele of the sphenoid sinus. 6a – MRI (frontal section); 6b – extended transnasal access. Plasty of the liquor defect after the meningocele removal (the material – fat).

 

Таблица 3. Виды хирургических вмешательств

Table 3. Types of surgical interventions

 

Expanded access (P.J. Wormald 2005, J.N. Palmer 2013), in contrast to the traditional one with mechanical expansion of the natural anastomosis, involves cutting out a short (5–10 mm) nasoseptal mucosal graft below and medially to the sinus anastomosis on a pedicle fed from the posterior septal branch of the pterygopalatine artery with a wide exposure and resection of the anterior wall of the sinus. We also expanded the anastomosis using a cutter. This method simplifies the process in case the natural anastomosis is not visualized or is not technically available and/or there is a need for a wide opening of the sinus. A pedicle graft is used to close a wide bone defect, which promotes its further epithelialization and minimizes the development of osteitis in the future. Studies by a number of authors indicate that transethmoidal and transnasal approaches can equally be used in isolated sinus lesions. The transnasal approach is safer than the transethmoidal and is the method of choice for isolated sinus involvement, provided that the pathological process in the sinus does not require extensive revision and/or the creation of a sufficient volume of fenestration in situations of high risk of recurrence.

There were no complications in the postoperative period. On days 5–7, all patients underwent endorinoscopy. Control CT was performed in 11 patients within 2 to 3 months; the rest of the patients (from remote areas) however did not undergo the control examination. When performing an extended approach, the formation of a persistent, epithelized anastomosis was possible to achieve in all cases (Figures 7, 8). With polypous-purulent forms of sphenoiditis, relapses of the disease were most often registered, requiring only anti-inflammatory therapy and irrigation of the sinus through the formed anastomosis (Figure 9).

 

Рисунок 7. Соустье через 1 год после расширенного доступа.

Figure 7. Anastomosis 1 year after expanded access.

 

Рисунок 8. Соустье через 3 года после расширенного трансназального доступа.

Figure 8. Anastomosis 3 years after expanded access.

 

Рисунок 9. Рецидив полипозно-гнойного сфеноидита через 6 месяцев после операции.

Figure 9. Recurrence of polypous-purulent sphenoiditis in 6 months after surgery.

 

The incidence of adhesive process after interventions was approximately 20%, while cicatricial adhesion caused by the recurrence of the pathological process and requiring revision intervention was seen in three cases only. In one of the cases, a patient with a history of sphenotomy for chronic sphenoiditis was identified to have the Onodi cell, in which the fungal inflammation was localized, not opened (recognized), and required repeated surgery.

CONCLUSIONS

Isolated sphenoiditis amounted to 3% in the structure of patients who underwent endosurgical treatment for PNS pathology (approximately 30% of the total number of sphenoiditis). In the hospital, patients with a diagnosis of isolated sphenoiditis established precisely at the prehospital stage accounted for no more than 12% of the total, and this may either be due to underdiagnosis, a passive position in relation to the pathology of the sphenoid sinus in outpatient doctors, or caused by approach errors. The predominance of MRI diagnosis in prehospital examination and the ignorance of CT studies by specialists were noted.

Surgery was the main method of treatment for isolated sphenoiditis, with the extended transnasal approach being the most commonly used. The combination with drug treatment in the postoperative period is however required.

Further studies are necessary to study the aspects, safety and clinical efficacy of various endosurgical approaches.

Conflict of interest. The authors declare no conflict of interest.

About the authors

Roman A. Larin

Nizhnii Novgorod Regional Clinical Hospital named after N.A. Semashko

Author for correspondence.
Email: info.lor@mail.ru

the Head of the Department of Otorhinolaryngology.

Svetlana V. Krasilnikova

Privolzhskii Research Medical University

Email: info.lor@mail.ru

PhD, assistant of the Chair of Otorhinolaryngology.

Andrey V. Shakhov

Privolzhskii Research Medical University

Email: info.lor@mail.ru

PhD, Professor, the Head of the Chair of Otorhinolaryngology.

Polina V. Suzaeva

Privolzhskii Research Medical University

Email: info.lor@mail.ru

assistant of the Chair of Otorhinolaryngology

Evgeni N. Pisarev

Privolzhskii Research Medical University

Email: info.lor@mail.ru

PhD, Associate Professor, Chair of Otorhinolaryngology.

References

Supplementary files