gms | German Medical Science

Despite recent advances in therapy for sinusitis, extra and intracranial complications, particularly most dangerous and potentially fatal – brain abscesses remain a contemporary problem. The number of patients which develop intracranial complications due to rhinosinusitis has been reported as being between 0,5–24%. It appears that most referral centers see one to three cases per year [Ref. 1], [Ref. 2], [Ref. 3]. They may occur after acute or more often chronic sinusitis, and include subdural empyema, intracerebral abscess, extradural empyema, meningitis, cavernous or superior sagittal sinus thrombosis and osteomyelitis [Ref. 1], [Ref. 2], [Ref. 4], [Ref. 3].

The paranasal sinuses form an integral part of the anterior and middle skull base with the venous network that traverses this area [Ref. 5], [Ref. 6]. There are two paths of infection spreading to the intracranial cavity:

1.

retrograde thrombophlebitis through diploic veins of the skull and ethmoid bone or communicating veins;

2.

direct extension of disease through anatomic pathways, such as congenital or traumatic dehiscence, sinus wall erosion and existing foramina (i.e., olfactory nerves) [Ref. 7], [Ref. 2], [Ref. 4], [Ref. 3].

The most common presenting symptoms of intracranial involvement are an altered mental state, headache, fever, seizure, vomiting, a unilateral weakness or hemiparesis and a cranial nerve sign [Ref. 3], [Ref. 8]. It should be mentioned that the frontal lobe, which is the most common site of intracranial abscess formation due to rhinosinusitis, is also known as a neurologically silent area of the brain. Therefore, there may be only subtle changes in mood or personality that are easily misinterpreted [Ref. 7], [Ref. 4], [Ref. 3]. On the other hand, the broad use of antibiotics which caused decreased frequency and severity of intracranial complications can mask or even abolish their signs and symptoms [Ref. 2], [Ref. 9].

The current report is a retrospective study of 32 patients admitted to the Department of Otolaryngology in Poznan, Poland, over the past 40 years (1964–2005) with the intracranial complications due to rhinosinusitis. Patients were diagnosed based on physical examination, rhinological, neurological, ophtalmological with a special stress to eyegroungs examination and different diagnostic tools used in the adequate period of time (EEG, conventional radiology and angiography and than CT followed by MRI scan). Their characteristics, symptoms and signs, management and mortality are presented and discussed.

Thirty two patients with intracranial complications secondary to rhinosinusitis were treated at the Department of Otolaryngology in Poznan over the past 40 years. There were 10 women and 22 men. The male to female ratio was 2:1. The age range was 12–47 years. The majority of patients were young adult male up to 30 years old. Those patients had 38 intracranial complications and in 8 cases (25% of all patients) multiple complications were observed (Table 1 [Tab. 1])

The distribution of affected sinuses was as follows: pansinusitis – nineteen patients; frontal – six patients; ethmoid – five patients, maxillary – 2 patients. Isolated inflamation of sphenoid sinus was not observed. Seventy five percent of patients had chronic sinusitis, and the other 25% acute sinusitis. The range of duration of rhinosinusitis symptoms exacerbation was 7 to 25 days.

The most common presenting signs and symptoms were headache (85%), fever (70%), impaired consciousness (50%), nausea and vomiting (36%). Other symptoms included convulsions, neck stiffness, hemiparesis and cranial nerves palsy (III, IV, VI, VII). On admission, as soon as possible, the rhinological, neurological and ophtalmological examinations were performed. Than laboratory test included lumbal puncture and bacteriological and mycological test of sinus pus were taken. In the meantime the CT followed by MRI were done. The material for bacteriological examination was retaken during surgical procedure. Organisms were cultured from intracranial pus in 50% of cases. Staphylococcus aureus was the most common organism cultured followed by Staphylococcus albus, Streptococcus alpha hemoliticus and others.

All patients were treated as an emergency case and broad-spectrum intravenous antibiotics were administrated. Such treatment was continuated for a total period of 4 to 6 weeks. A combination of penicilline and metronidasole was initially recommended and later altered based upon the results of culture and sensitivity test. Patients underwent surgical intervention of the sinus. In the last 5 cases combined approach – the functional endoscopic sinus surgery with the external frontal sinus drainage was performed. In the other cases external frontoethmoidectomy and/or Caldwell–Luc procedure were done. Simultaneously in patients with frontal lobe abscess, after the exposure of the dura, the puncture was performed according to the radiological findings. Then in a distance of 15–20 minutes, the abscess was replaced by a mixture of saline and antibiotic with the neonates’ transfusion syringe (Zakrzewski's method) [Ref. 10]. In the cases with epidural and subdural empyema the abscess opened itself during exposure and careful drainage was performed. The total survival rate for intracranial complications secondary to rhinosinusitis was 87,5%. Among 32 patients 4 have died. Of the 28 patients who survived 3 developed epilepsy.

The incidence of intracranial complications secondary to sinusitis has dramatically decreased after introduction of diagnostic methods such as CT and MRI, widespread use of antibiotics. Since that incidence of intracranial complications have changed a little, particulary due to introduction of modern surgical techniques [Ref. 11], [Ref. 12], [Ref. 13]. In the earlier decades the majority of intracranial complications corresponded to chronic otitis media, but recently it has been suggested that the rhinosinusitis becoming nearly as common as otological disease as the primary source of brain abscesses [Ref. 3]. In the current study intracranial complications were most commonly seen in young male patients with a history of chronic sinusitis. There is a general agreement to young age and male sex in the literature [Ref. 14], but on the contrary to our findings and some other series, Jones et al. suggested the prevalence of intracranial complications secondary to acute sinusitis [Ref. 1], [Ref. 2], [Ref. 4], [Ref. 3]. One possible explanation for the constant age distribution is that in younger individuals the valveless diploic system is at its most vascular, providing a good conduit for bacterial infection, and that the posterior wall of maturing frontal sinuses is a poor barrier to the spread of microorganisms [Ref. 3]. According to the literature intracranial complications resulted most often from the ethmoiditis and sphenoiditis, although it has been noted that sphenoiditis has decreased in antibiotic era [Ref. 1], [Ref. 9]. In current review the intracranial complications usually was due to ethmoiditis and frontoiditis.

There are variable data on frequency of particular intracranial complications secondary to rhinosinusitis. Claymann et al. found cerebral abscess to be most common [Ref. 1] whereas Hutchin et al. indicate subdural empyema to be dominant [Ref. 15]. In the other series the prevalence of epidural empyema was suggested [Ref. 12], [Ref. 2], on the contrary Younis et al. has found meningitis to be the most common [Ref. 9]. In the current study cerebral abscesses were the most often seen complications. Incidences of multiple intracranial complications in the same patients should be also emphasized. Such multiple intracranial complications were found by other authors too [Ref. 4].

The most typical clinical presentation of intracranial complications include: acute or chronic sinonasal complaints, along with fever, headache, nausea, vomiting alter mental status, neck stiffness. It should be stressed that the early stages of intracranial complications may be asymptomatic and that the focal neurological signs (such as seizures or hemiparesis) are the symptoms of the late stage of disease with poor prognosis [Ref. 7], [Ref. 4], [Ref. 3], [Ref. 9]. In our series headache, fever, impaired consciousness, nausea and vomiting were the most common presenting symptoms. Our findings reflect those of other contemporary authors [Ref. 7], [Ref. 4], [Ref. 3], [Ref. 9]. Patients with such signs and symptoms in the presence of sinusitis require an accurate diagnosis. In our opinion it is reasonably to use both CT and MRI in the same patient. It appears that CT is superior in bone imaging and provides an excellent depiction of airbone and air-soft tissue interfaces, which are necessary to the sinus surgeon [Ref. 2], [Ref. 16], [Ref. 13]. While MRI provides superior soft tissue resolution and this is of particular utility in the detailed evaluation of intraorbital disease and in assessing the cavernous sinus or brain abscess [Ref. 2], [Ref. 13].

All patients diagnosed as having intracranial complications should be treated as emergency cases. On the contrary to the some other authors we used to pay a special attention to immediate surgical intervention of the sinus [Ref. 2], [Ref. 9]. Additionally some patients (with brain abscess, subdural or epidural empyema) require surgical drainage. In our department the Zakrzewski’s method is used for many years [Ref. 10]. The first step of the procedure is the primary lesion removal and than at the same operation the treatment of the abscess by the puncture. The content of the abscess is replaced with mixture of saline and antibiotic. The last step can be repeated for several times in a distance of 15–20 minutes. The advantage of our technique is keeping the abscess volume on the same level. This technique is therefore less invasive then neurosurgical treatment. Besides advantages of application the antibiotic to the abscess cavity must be emphasised [Ref. 2]. The procedure could be repeated 2–3 times in a distance of 3–5 days depended on the clinical stage of the patients and on the MRI findings

Besides, all patients should be treated with high-dose intravenous antibiotics. Such an approach allows obtaining results compare well with those of the recent literature. The total mortality rate during the last 40 years was 13% and 10% had long-term neurological sequels [Ref. 16]. The reported mortality and morbidity rate in the literature ranging from 0–30 and 13–45 respectively [Ref. 11], [Ref. 1], [Ref. 2], [Ref. 4], [Ref. 9]. In our opinion the most important in successful management of intracranial complications is an early and accurate diagnosis, as well as immediate surgical intervention.

In summary we conclude that although a decreased in the incidence of intracranial complications is observed this entity may still be life-threatening. Therefore an adequate diagnosis should be stated as soon as possible. After the diagnosis is stated the patient should undergo surgical intervention as an emergency procedure.