Infratentorial empyema: analysis of 22 cases

Empyemas secondary to ENT infections in children before, during and after the COVID-19 pandemic

OBJECTIVES

This study aims to analyze a series of cases admitted with intracranial empyema, either subdural or epidural, secondary to otorhinolaryngological (ENT) infections over a period of 10 years, including the COVID-19 pandemic. The incidence, characteristics, severity, and management of these conditions, as well as the influence of COVID-19, are described below.

METHODS

The authors conducted a retrospective review of all of the children admitted to the Pediatric Neurosurgery Department of Nancy with intracranial empyemas secondary to a confirmed sinus (sinogenic) or mastoid (otogenic) infection between 2014 and 2024. They recorded their age, clinical presentation, initial Glasgow Coma Scale (GCS) score, bacteriological results, as well as the number and type of neurosurgical procedures they were subjected to, and their clinical outcome. These results were compared across two periods: before, and after the start of the COVID-19 pandemic.

RESULTS

Nineteen children in total were surgically treated, with twelve having a subdural location for their empyema, and seven located exclusively in the epidural compartment. The clinical presentation and evolution were positive in all except for one epidural empyema (6/7), and in the majority of the subdural locations (10/12). Twelve patients (63,16%) were treated after the start of the COVID pandemic, including 11 between 2022 and 2023. No differences were observed in patient characteristics, bacterial population and prognosis between these two periods. No patient was proven positive for COVID-19 at the time of their treatment.

CONCLUSIONS

Empyemas secondary to ENT infections are potentially serious pathologies, whose prognosis has clearly improved over the years. The incidence has significantly increased during the COVID-19 pandemic, without changing the characteristics or prognosis of the pathology. This increase mainly took place in the last 2 years of the pandemic in our department. The incidence remains even higher than before 2020.

Pediatric infratentorial subdural empyema: A case report

BACKGROUND

Infratentorial subdural empyemas in children are extremely rare and potentially lethal intracranial infections. Delay in diagnosis and therapy is associated with increased morbidity and mortality.

CASE DESCRIPTION

A 4-year-old boy presented with cerebellar signs following a failed treatment of otitis media. Imaging studies revealed a subdural empyema and left transverse and sigmoid sinus thrombosis. The empyema was evacuated operatively and antibiotic treatment was initiated and administered for 6 weeks. The patient recovered fully and was discharged 4 weeks following the evacuation of the empyema.

CONCLUSION

While prompt identification and treatment of subdural infratentorial empyemas are crucial for favorable outcomes, their diagnosis in children might be initially missed. This is, in part because they are so rare and in part, because imaging artifacts arising from the complex posterior fossa anatomy may obscure their presence in the computer tomography (CT) scan. Therefore, high level of suspicion is necessary, given the appropriate history and clinical presentation. In children, this is a recent history of protracted otitis media and central nervous system symptomatology-cerebellar or other.

Management of infections associated with neurocritical care

The reported incidence of hospital-acquired infections (HAIs) in the neurointensive care unit (NICU) ranges from 20% to 30%. HAIs in US hospitals cost between $28 and $45 billion per year in direct medical costs. These infections are associated with increased length of hospital stay and increased morbidity and mortality. Infection risk is increased in NICU patients due to medication side-effects, catheter and line placement, neurosurgical procedures, and acquired immune suppression secondary to steroid/barbiturate use and brain injury itself. Some of these infections may be preventable but many are not. Their appearance do not always constitute a failure of prevention or physician error. Neurointensivists require indepth knowledge of common nosocomial infections, their diagnosis and treatment, and an approach to evidence-based practices that improve processes of care and reduce HAIs.

Which should be appropriate surgical treatment for subtentorial epidural empyema? Burr-hole evacuation versus decompressive craniectomy: Review of the literature with a case report

Subtentorial empyema is a rare intracranial complication of chronic otitis media. Moreover, if not correctly treated, it is a life-threatening infection. Epidural and subdural empyemas on subtentorial space have different effects. This difference is not mentioned in literature. If the distinction can be made, surgical treatment method will be different, and the desired surgical treatment may be less minimal invasive. A 26-year-old male patient was found to have developed epidural empyema in the subtentorial space. We performed a burr-hole evacuation in this case because there was low cerebellar edema, Also, the general condition of the patient was good, the empyema was a convex image on the lower surface of tentorium on magnetic resonance images, and when the dura mater base is reached during mastoidectomy for chronic otitis media, we were observed to drain a purulent material through the epidural space. After 10 days from surgery increased posterior fossa edema caused hydrocephalus. Therefore, ventriculoperitoneal shunt insertion was performed. The patient fully recovered and was discharged after 6 weeks. Complete correction in the posterior fossa was observed by postoperative magnetic resonance imaging. Burr-hole evacuation from inside of the mastoidectomy cavity for subtentorial epidural empyema is an effective and minimal invasive surgical treatment.

Cerebellopontine angle subdural empyema in a 2-years old patient with bilateral mastoiditis - a life-threatening condition. Case presentation and review of literature

Infratentorial subdural empyema is a life-threatening condition, the common source being an ear infection. We present a 2-year old boy treated for bilateral mastoiditis, with infratentorial-left cerebellopontine angle subdural empyema. Clinical presentation encompassed a systemic febrile illness, headaches, and a stiff neck. Empyema was diagnosed with computed tomography and magnetic resonance imaging. The patient was successfully treated with surgery and appropriate antibiotics. Empyema should be considered in patients with ENT infection associated with neurological signs that suggest a posterior fossa lesion.

Bilateral symmetrical infratentorial subdural empyema: Delay proves detrimental

Authors report a case of infratentorial subdural empyema, a rare complication of neglected otitis media in a child.

Penetrating shrapnel injuries of the posterior fossa

BACKGROUND

Gunshot injuries of the posterior fossa are rare and may follow a fatal course. In posterior fossa gunshot injuries, cerebellar hematoma, contusion, obstruction of cerebrospinal fluid (CSF) circulation by the shrapnel, and intracranial hypertension caused by autoregulation loss lead to mortality in the early stage.

METHODS

In this study, four cases of patients who underwent surgical intervention after penetrating shrapnel injuries of the pure posterior fossa were evaluated.

RESULTS

All of the patients were male; their mean age was 26.5 ± 5 years. The lowest and highest Glasgow Coma Scale scores were 4 and 12, respectively. Neural injury was detected by computed tomography performed after systemic and neurological examination following admission to the emergency service. The shrapnel was found in the cerebellar tissue in three cases and in the fourth ventricle in one case. Following preoperative procedures, surgery was performed with the patient in the prone position. Postoperative monitoring revealed no CSF fistula, meningitis, or hydrocephalus. None of the patients required revision surgery. There were no postoperative mortalities.

CONCLUSION

Due to the small volume of the posterior fossa, acute pathologies may lead to rapid neurological deterioration and death. Early surgical intervention and close postoperative follow-up after penetrating shrapnel injuries of the posterior fossa play a significant role in reducing mortality and morbidity.

Parietal subdural empyema as complication of acute odontogenic sinusitis: a case report

Introduction

To date intracranial complication caused by tooth extractions are extremely rare. In particular parietal subdural empyema of odontogenic origin has not been described. A literature review is presented here to emphasize the extreme rarity of this clinical entity.

Case presentation

An 18-year-old Caucasian man with a history of dental extraction developed dysarthria, lethargy, purulent rhinorrhea, and fever. A computed tomography scan demonstrated extensive sinusitis involving maxillary sinus, anterior ethmoid and frontal sinus on the left side and a subdural fluid collection in the temporal-parietal site on the same side. He underwent vancomycin, metronidazole and meropenem therapy, and subsequently left maxillary antrostomy, and frontal and maxillary sinuses toilette by an open approach. The last clinical control done after 3 months showed a regression of all symptoms.

Conclusions

The occurrence of subdural empyema is an uncommon but possible sequela of a complicated tooth extraction. A multidisciplinary approach involving otolaryngologist, neurosurgeons, clinical microbiologist, and neuroradiologist is essential. Antibiotic therapy with surgical approach is the gold standard treatment.

Escherichia coli positive infratentorial subdural empyema secondary to mastoiditis and underlying cholesteatoma

Infratentorial subdural empyema is a neurosurgical emergency that is associated with an alarmingly high morbidity and mortality if appropriate management is delayed. It is an important differential to consider when confronted with a patient with a reduced Glasgow Coma Scale, focal neurology and symptoms of raised intracranial pressure in the presence of a head and neck infection. It is also important that the primary team managing these patients is aware of the many pathogens that may be involved, including Escherichia coli. Early recognition, prompt diagnosis, timely involvement of the appropriate multidisciplinary teams, including neurosurgery, otorhinolaryngology, radiology and microbiology should be sought, and urgent intervention are imperative in avoiding a fatal outcome. This article presents a case of E coli-positive infratentorial subdural empyema secondary to mastoiditis due to underlying cholesteatoma, and a review of the pertinent literature.

Burr hole evacuation for infratentorial subdural empyema

Infratentorial empyema is a life threatening condition and constitutes a neurosurgical emergency. Purulent mastoiditis and medial otitis is the most common origin and a thorough eradication of the purulent foci is mandatory. Decompression craniectomy has been primarily advised in the literature as the gold standard of the surgical treatment but burr hole evacuation when there the lack of cerebellar edema is less invasive and deemed equally efficient in the few reported cases. This is the report of a seventeen year old female who presented in a comatose state due to infratentorial empyema with acute hydrocephalus and who improved immediately after burr hole evacuation. Details of the surgical procedures are given. Mastoidectomy was completed, with the patient under combined antibiotherapy. She leads a normal life now, more than six years after surgery.

Infratentorial subdural empyemas mimicking pyogenic meningitis

Infratentorial subdural empyema is an extremely rare condition which unfortunately mimics pyogenic meningitis in 75% of cases. While an ill-planned lumbar puncture in these cases may be fatal, an inadvertent delay in treatment may be detrimental to the outcome for the patient. We present a case of a young boy with long standing history of chronic suppurative otitis media (CSOM) presenting with an infratentorial empyema with features suggestive of pyogenic meningitis. We also review the available literature to further define the condition in terms of clinical features, treatment options, and outcome. A misdiagnosis of this condition with failure to institute appropriate surgical intervention and antibiotic therapy is potentially life threatening. We highlight this rare condition which requires a high degree of suspicion especially in the presence of associated risk factors.

Brain abscess: management and outcome analysis of a computed tomography era experience with 973 patients

OBJECTIVE

Brain abscess (BA) is a neurosurgical emergency and despite significant medical advances, it remains a surgical challenge. A single institution's two decade computed tomography era management experience with BA is reported.

METHODS

A retrospective analysis of patients with BA, admitted to the Department of Neurosurgery, Wentworth Hospital, Durban, KwaZulu-Natal, South Africa, was performed. The medical records were analyzed for demographic, clinical, neuroimaging, neurosurgical and otolaryngology management, microbiological characteristics, and their relationship to outcome.

RESULTS

During a 20-year period (1983-2002), 973 patients were treated. The mean age was 24.36 ± 15.1 years (range: 0.17-72 years) and 74.2% (n = 722) were men. The mean admission Glasgow Coma Score was 12.5 ± 2.83. The majority of BAs were supratentorial (n = 872, 89.6%). The causes were otorhinogenic (38.6%), traumatic (32.8%), pulmonary (7%), cryptogenic (4.6%), postsurgical (3.2%), meningitis (2.8%), cardiac (2.7%), and "other" (8.6%). Surgical drainage was performed in 97.1%, whereas 19 patients had nonoperative management. The incidence of BA decreased during the study period. Patient outcomes were good in 81.3% (n = 791), poor in 5.3% (n = 52), and death (13.4%, n = 130) at discharge. The management morbidity, which included postoperative seizures, was 24.9%. Predictors of mortality were cerebral infarction (odds ratio [OR] 31.1), ventriculitis (OR 12.9), coma (OR 6.8), hydrocephalus (OR 5.1), dilated pupils (OR 4.8), bilateral abscesses (OR 3.8), multiple abscesses (OR 3.4), HIV co-infection (OR 3.2), papilledema (OR 2.6), neurological deterioration (OR 2.4), and fever (OR 1.7).

CONCLUSIONS

Optimal management of BA involves surgical drainage for medium-to-large abscesses (≥2.5 cm) with simultaneous eradication of the primary source, treatment of associated hydrocephalus, and administration of high doses of intravenous antibiotics. The incidence of BA is directly related to poor socioeconomic conditions and therefore, still poses a public health challenge in developing countries.

Falcotentorial subdural empyema: analysis of 10 cases

OBJECT

Parafalcine subdural empyema and those along the superior and inferior surface of the tentorium are rare entities. We present a series of 10 patients where we have attempted to describe the pathophysiology, clinical features, and management of subdural empyema.

METHODS

The study group included 10 cases of falcotentorial subdural empyemas managed between 2004 and 2010. The mean age group was 14.4 years. Seven patients had empyema along the falx or superior surface of tent, and the remaining three had empyema along the inferior surface of tent. Fever, raised intracranial pressure symptoms, falx syndrome, and seizures were the usual presenting features. These patients had an indolent presentation as compared to convexity subdural empyemas. The diagnosis was made based on radiology. Chronic suppurative otitis media was a causative factor in five patients; in the remaining patients, the source was ascribed to be hematogenous. All patients were treated with antibiotic therapy (6 weeks) ± surgery. Two patients were treated conservatively, and the remaining eight patients underwent definitive surgery in the form of craniotomy (supratentorial)/craniectomy (infratentorial) and evacuation of pus. The pus was limited within two leaves, one adherent to the falx/tent and the other one to the pia-arachnoid of adjacent parenchyma. The wall along the falx or tent could be peeled off easily and was excised in all cases to lay open the cavity widely. The wall along pia-arachnoid was left as it is. Pus culture was positive in four and blood culture positive in two cases. There was only a single mortality in our series. The outcome was assessed by the Glasgow Outcome Scale. The mean duration of follow-up was for 18.8 months, and all patients who survived had a good outcome.

CONCLUSION

Falcotentorial empyema remains a rare entity. The presentation is indolent as compared to convexity subdural empyemas, possibly due to its limitation secondary to arachnoid adhesions at the junction of falx, tent, and convexity dura. The main stay of management remains craniotomy, evacuation, and partial excision of the wall, laying it completely open, unless it is extremely thin. With appropriate surgery and antibiotic therapy, a good outcome can be expected.

Posterior fossa subdural empyema in children--management and outcome

AIMS

The aims of this study were to analyze the clinical features, radiologic findings, bacteriologic spectrum, and management protocols and outcomes in posterior fossa subdural empyemas in children.

MATERIALS AND METHODS

This study is a retrospective analysis of all children (age, <18 years) treated over a ten-year period (1994-2004) at NIMHANS, India. Clinical, bacteriologic, radiologic, and follow-up data were analyzed.

RESULTS

Twenty-seven children with posterior fossa empyemas were treated during this period, making this the largest series to date dealing with this rare entity. Posterior fossa empyemas are seen more commonly in the summer months and in males. Of the patients, 74.1% were in altered sensorium. The clinical features included the triad of fever, headache, and vomiting, which is a nonspecific picture. Cerebellar signs were elicited only in 40%. The most common source was untreated middle ear infection. Pus usually accumulates over the cerebellar convexity and is associated with hydrocephalus in 74% of patients. Cultures of the empyema pus were positive in 74% of cases, and 18.5% had polymicrobial infections. Only 21% of the patients needed a permanent CSF diversion procedure. Craniectomy is the treatment of choice in these cases.

CONCLUSIONS

The clinical features are nonspecific. Early surgery can salvage most patients and obviate the need for permanent CSF diversion procedures. Surgery (evacuation of empyema and mastoidectomy), antibiotics, and management of hydrocephalus are the mainstays of treatment.

Focal intradural brain infections in children: an analysis of management and outcome

INTRODUCTION

Focal intradural infections of the brain include empyema and abscess in the supratentorial and infratentorial spaces. These are amenable to surgical management. Various other issues may complicate the course of management, e.g. hydrocephalus with infratentorial lesions or cortical venous thrombosis with supratentorial lesions. Here, we review the management and identify factors affecting outcome in these patients.

MATERIALS AND METHODS

This is a retrospective analysis of all children (aged <18 years) treated at the National Institute of Mental Health and Neurosciences, Bangalore, India, between 1988 and 2004. Case records were analyzed to obtain clinical, radiological, bacteriological and follow-up data.

RESULTS

There were 231 children who underwent treatment for focal intradural abscess/empyema at our institute. These included 57 children with cerebral abscess, 65 with supratentorial empyema, 82 with cerebellar abscess and 27 with infratentorial empyema. All patients underwent emergency surgery (which was either burr hole and aspiration of the lesion or craniotomy/craniectomy and excision/evacuation), along with antibiotic therapy, typically 2 weeks of intravenous and 4 weeks of oral therapy. The antibiotic regimen was empiric to begin with and was altered if any sensitivity pattern of the causative organism(s) could be established by culture. Hydrocephalus was managed with external ventricular drainage initially and with ventriculoperitoneal shunt if warranted. Mortality rates were 4.8% for cerebral abscess, 9.6% for cerebellar abscess, 10.8% for supratentorial subdural empyema and 3.7% for posterior fossa subdural empyema. The choice of surgery was found to have a strong bearing on the recurrence rates and outcome in most groups, with aggressive surgery with craniotomy leading to excellent outcomes with a low incidence of residual/recurrent lesions.

CONCLUSIONS

Antibiotic therapy, emergency surgery and management of associated complications are the mainstays of treatment of these lesions. We strongly advocate early, aggressive surgery with antibiotic therapy in children with focal intradural infections.

Unusual CNS infection from a subtorcular dermal sinus

A 14-month-old toddler with a previously unrecognized dermal sinus tract presented with hydrocephalus and raised intracranial pressure. CT and MRI revealed a large posterior fossa dermoid mass. Cultures obtained from CSF and posterior fossa subdural empyema were positive for both Staphylococcus aureus and Escherichia coli. To the authors's knowledge, this is the first such report.

CONCLUSION

This case suggests that children who present with CNS infections with unusual pathogens should be carefully evaluated for the presence of anatomic abnormalities including dermal sinus tracts.

Cranial and spinal subdural empyema

Subdural empyema represents a loculated suppuration between the dura and the arachnoid. It has been described either intracranially or in the spinal canal, the latter localization being quite rare. It is a rare but serious illness with a declining mortality rate but rather frequent neurological sequelae. Morbidity and mortality in intracranial and spinal subdural empyema directly relate to the delay in diagnosis and therapy. The epidemiology, etiology, pathophysiology and symptoms of spinal subdural empyema and cranial subdural empyema are somewhat different, but brain and spinal subdural empyema are not always two different entities. An adequate treatment strategy should be selected on a case-by-case basis, especially for patients with a massive CNS involvement, where management represents a challenge.

THE SURGICAL MANAGEMENT OF INFECTIONS INVOLVING THE CEREBRUM

OBJECTIVE

Infection involving the cerebrum is a true neurosurgical emergency that requires rapid diagnosis and appropriate surgical and medical intervention to achieve good clinical outcome.

METHODS

Because of the potential for devastating neurological sequelae, it is imperative that neurosurgeons be involved in the diagnosis and management of these serious conditions once an infection is suspected. With the advent of computed tomography and magnetic resonance imaging, it is now possible to detect an infectious process early in its course and follow the response to therapy. Although significantly more effective than in the past, antimicrobial therapy alone is insufficient to eradicate most intracranial infections, especially in the presence of compression or displacement of the cerebrum. Surgery remains an essential part of the management of intracranial infection because of its ability to provide immediate relief from pressure on neural structures and thereby result in clinical improvement.

RESULTS

The most common infections affecting the brain, namely, cranial epidural abscess, subdural empyema, brain abscess, viral infection, tuberculosis, and neurocysticercosis, can each be associated with significant mass effect on the cerebrum that is greatly reduced through surgery. This relief, in combination with newer antimicrobial agents that have an improved ability to cross the blood brain barrier, has led to a reduction in the infection-related morbidity and mortality rates associated with intracranial infections.

CONCLUSION

Combining advanced imaging and surgical techniques in the form of intraoperative magnetic resonance image-guided neurosurgery may further enhance clinical outcomes in these once uniformly fatal diseases.

Vascular and Parameningeal Infections of the Head and Neck

Vascular and parameningeal infections of the head and neck are rare but frequently life threatening. These infections include intracranial and extracranial septic venous thrombophlebitis, arterial mycotic aneurysms and erosions, subdural empyema, and epidural abscesses. They usually arise as complications of otogenic, oropharyngeal, or paranasal sinus infections, and management involves an aggressive combined medical-surgical approach.

Otogenic cerebellar abscess due to purulent labyrinthitis and defect of the superior semicircular canal and its propagation through the endolymphatic sac

The otogenic cerebellar abscess still is one of the most dangerous complications of otitis media and implicates a high risk of mortality. Early diagnosis and therapy are decisive factors for the chances of rehabilitation. Radiologic imaging (CT/MRI) plays an important role. A broad-spectrum antibiotic according to antibiogram is indispensable. The type of surgical intervention depends on the cause and localization of the abscess. In this case the cerebellar abscess was a complication resulting from labyrinthitis, which was propagated through the endolymphatic duct and sac to the posterior fossa dura. Consequently, it could be cured ultimately only after petrosectomy and abscess drainage toward the mastoid cavity. It is mandatory to completely sanitize the infection surgically in order to avoid lethal complication especially in case of a delayed clinical course or recurrent symptoms of labyrinth involvement. Close interdisciplinary collaboration between ORL, neurosurgery and neuroradiology is desirable for successful therapy.

Subdural empyema and other suppurative complications of paranasal sinusitis

Suppurative intracranial infection, including meningitis, intracranial abscess, subdural empyema, epidural abscess, cavernous sinus thrombosis, and thrombosis of other dural sinuses, are uncommon sequelae of paranasal sinusitis. A high index of suspicion is necessary to identify these serious complications. We present a patient with subdural empyema in whom the diagnosis was delayed, followed by a discussion of suppurative complications of sinusitis. The case shows the rapid progression of subdural empyema, which represents a true neurosurgical emergency requiring prompt diagnosis and management.

Pediatric infratentorial subdural empyema: analysis of 14 cases

OBJECT

Pediatric cases of infratentorial subdural empyema (SDE) are both rare and associated with high rates of morbidity and mortality. The goal of this study was to report patient characteristics, treatment, and outcome in an exclusively pediatric series of SDE cases.

METHODS

A series of 14 pediatric cases of infratentorial SDE was retrospectively analyzed. All patients were treated between 1994 and 2004. Sixty-four percent of the patients were boys; the majority of cases occurred during the summer months. Clinical features included headache, fever, vomiting, meningism, and otorrhea. Cerebellar signs were found only in 21% of patients. In 85.7% of the cases, the patients presented with a depressed level of consciousness (Glasgow Coma Scale Scores 11-15). In 79.6%, pus collection was seen over the cerebellar convexity; interhemispheric and tentorial collections were also observed in some cases. Hydrocephalus was present in 92.9% of patients. Five patients required external ventricular drainage during surgery or postoperatively. Shunt placement was required in 21% of cases. All patients were treated with antibiotic therapy and surgery (bur holes in 21% of the cases, craniectomy in 79%). Pus cultures demonstrated microbial infection in 71.4%, and polymicrobial infection in 21%. Four patients required repeated surgery for reaccumulation of pus. Minor postoperative complications developed in three patients. All 14 patients survived. At follow up, the Glasgow Outcome Scale scores were 4 or 5 in all cases.

CONCLUSIONS

Early diagnosis and prompt surgical treatment are crucial in cases of SDE. With appropriate surgery, antibiotic therapy, and management of hydrocephalus, good outcome can be expected.

Subdural empyema and cerebellar abscess due to chronic otitis media

The infratentorial variety of the subdural empyema, with or without coexisting cerebellar abscess, is a rare clinical entity that carries a high mortality rate. We briefly describe the case of a 49-year-old man presented with severe debility, fever and an obviously neglected chronic otitis media. The patient had refused surgical treatment several months ago. After admission, his level of consciousness began to deteriorate, and the radiological studies showed infratentorial subdural suppuration extending into the right cerebellar hemisphere, along with chronic pyogenic infection of the middle ear and the mastoid process. Radical mastoidectomy was performed first, followed by extensive right posterior fossa craniectomy. The two subdural collections and the cerebellar abscess were successfully evacuated. Subsequently, he received post-operative antibiotic treatment for 6 weeks. At follow-up, 10 months after surgery, his neurological recovery was complete except for a minor residual cerebellar dysfunction on the right. This unusual case highlights that in patients presented with severe intracranial complications of chronic otitis media, early diagnosis and radical surgical intervention may be life saving.

Supra- and Infratentorial Subdural Empyema Secondary to Septicemia in a Patient With Liver Abscess-Case Report-

An 81-year-old man presented with subdural empyema in the left parietotemporal convexity 2 months after treatment under diagnoses of liver abscess and septicemia. Systemic investigation found no evidence of otorhinological or other focal infection except for liver abscess. Emergency drainage of pus was performed via a single burr hole and additional intravenous antibiotics were administered. Six weeks later, magnetic resonance imaging revealed subdural empyema in the right cerebellopontine angle in addition to recurrence of pus in the left parietotemporal subdural space. Ischemic changes were also shown in the right cerebellar hemisphere and brainstem. Although subdural empyema secondary to septicemia is rare, the possibility of this type of intracranial infection must be kept in mind, especially in compromised patients with septicemia.

Evaluation of the behaviour of a thermal diffusion sensor in a high field strength magnetic resonance system: an experimental study

Patients with acute brain pathology requiring ferromagnetic bio-medical implants for on-going invasive monitoring are largely excluded from the benefits of MRI scanning. We evaluated the behaviour of a thermal diffusion cortical blood flow (TD-CBF) sensor both in vitro (phantom gelatin model) and in vivo environments in a high field strength MRI system. Two baboons underwent cranial subdural implantation of 2 TD-CBF sensors/hemisphere and a single left parietal sensor was implanted subcortically to determine any deleterious effects. Using standard MRI sequences, artefact size, thermal effects, current generation, movement and reliability of recordings were assessed during scanning. The deflection forces were negligible, no observable thermal effects were demonstrated, while wide fluctuations in cerebral blood flow recordings were recorded. Mean image artefact size for implanted sensors was 6 times larger than in vitro. Patients with an implanted TD-CBF sensor may be safely imaged provided the device is disconnected. The MRI images obtained are of an acceptable quality.

Civilian infratentorial gunshot injuries: outcome analysis of 26 patients

BACKGROUND

Craniocerebral missile injuries have steadily increased to become the most common form of penetrating neurotrauma in our environment resulting in continued morbidity and neuropsychological sequelae. Civilian infratentorial gunshot injuries are uncommon but generally regarded as fatal injuries, with many patients dying before reaching hospital.

METHODS

A retrospective analysis of 1,069 patients with civilian gunshot wounds (GSW), admitted to our unit over a 14-year period (1986-2000), identified 26 patients with infratentorial gunshot injuries (2.4%). A detailed analysis of these patients was carried out, which included demographic factors, clinical and anatomic correlation, computed tomography scans, surgical management, and outcome.

RESULTS

All patients were male. The mean age was 26.5 +/- 11.5 years and the mean admission Glasgow Coma Score 11.8 +/- 2.7. Twenty-four of 26 patients required cerebrospinal fluid (CSF) diversion to control secondary hydrocephalus. The second commonest surgical procedure was posterior fossa decompression. Five of 26 patients died (19.2%). Severe morbidity was noted in 9 of 21 surviving patients (42.8%). Significant predictors: good outcome was associated with primary missile entry of the infratentorial compartment (p = 0.005), while patients with supratentorial to infratentorial missile trajectory were noted to have a poorer outcome (p = 0.041). Location of cerebellar injury (lateral or medial) and missile caliber had no significant influence on patient outcome.

CONCLUSION

Early control of incipient or established hydrocephalus and aggressive surgical management where appropriate, with careful postoperative monitoring, is necessary for good outcome in patients with civilian infratentorial missile injuries.

Craniotomy improves outcomes for cranial subdural empyemas: computed tomography-era experience with 699 patients

OBJECTIVE

Uncertainty regarding the best surgical management for subdural empyemas (SDEs) continues. Our unit has considered craniotomy the preferred method of surgical drainage for all cranial SDEs since 1988. We performed an analysis of our previously published, computed tomography-era, experience with 699 patients.

METHODS

Two analyses of the database (1983-1997) were performed. First, analysis of the periods from 1983 to 1987 and from 1988 to 1997 was performed. Second, analysis of the composite database was performed. Outcomes were compared for possible outcome predictors by univariate analysis. Multivariate analysis was used to identify variables that contributed independently to outcomes, using stepwise discriminant analysis.

RESULTS

Significant correlations between the analyzed periods with respect to outcome and type of surgery (P = 0.001) were noted. Analysis of the entire database (1983-1997) revealed a significant relationship between outcome and surgery type (P = 0.05). Pairwise comparison of limited procedures such as burr holes or craniectomies with wide-exposure surgical procedures such as primary craniotomies or procedures proceeding to full craniotomies indicated significant correlation with outcomes (P = 0.027). Reoperation and morbidity rates were increased with limited procedures. Stepwise discriminant analyses revealed that the type of surgery was correlated with outcomes (P = 0.0008, partial r(2) = 0.034).

CONCLUSION

Craniotomy was determined to be the surgical procedure of choice for treatment of cranial SDEs, allowing complete evacuation of the pus and, more importantly, decompressing the underlying cerebral hemisphere. Limited procedures such as burr holes or craniectomies may be performed for patients in septic shock, for patients with parafalcine empyemas, or for children with SDEs secondary to meningitis.

Focal intracranial infections due to Propionibacterium acnes: report of three cases

OBJECTIVE AND IMPORTANCE

Except for its role in shunt infections, Propionibacterium acnes has been of little interest to neurosurgeons. The rarity and indolent nature of focal intracranial infections by P. acnes limit their recognition. Three cases of serious intracranial infection due to this organism are described. CLINCAL PRESENTATION: Three patients with histories of immunosuppression and neurosurgical procedures developed nonspecific, delayed presentations (5 wk to 5 yr after surgery) of intracranial infections. In two patients, radiological investigations showed enhancing lesions that were later found to be brain abscesses. A subdural empyema was found in the third patient.

INTERVENTION

All three patients underwent surgical drainage of the purulent collections. P. acnes was isolated in each case, and each patient was treated with a 6-week course of intravenous penicillin. All three patients made good recoveries, and subsequent imaging showed no recurrence of the infectious collections.

CONCLUSION

P. acnes is an indolent organism that may rarely cause severe intracranial infections. This organism should be suspected when an intracranial purulent collection is discovered in a patient with a history of neurosurgical procedures. Immunosuppressed patients may be susceptible to this otherwise benign organism. Surgical drainage and treatment with intravenous penicillin should be considered standard therapy.

[Diagnosis of cerebellum-pontine angle tumors using artificial intelligence techniques]

We are concerned in this paper with learning classification procedures from known cases. More precisely, we provide a diagnostic model that discriminate between cerebellum-pontine angle (CPA) tumors and otorhinolaryngological (ENT) disorders. Usually, in order to distinguish between CPA tumors and ENT disorders one must perform clinical-neurological examination together with expensive radiological imagery (CT and MRI). The proposed model was obtained through artificial intelligence methods and presented a good accuracy level (88.4%) when tested against new cases, considering only clinical examination without radiological imagery results.

[Intracranial abscess and empyema: neurosurgical management]

Brain abscesses and empyemas are severe infections with lethal outcomes in the case of inappropriate treatment. The files of 34 patients with brain abscesses, and nine with intracranial empyemas treated over eight years (1990-1997) were analyzed retrospectively. Cases were evaluated for treatment and compared with data from the literature. Patients with brain abscess underwent either aspiration of the lesion through a burr hole (79.5% of the cases), or craniotomy and excision (8.8% of the cases); 11.7% were treated only with antibiotics. The operative mortality was 2.9% and the outcome was satisfactory in 85% of patients. These results are in agreement with data from the literature. Prognosis is strongly related to the initial clinical status. Current methods of treatment include surgical aspiration of large abscesses with a mass effect, and are usually associated with a poor clinical status. Excision is suggested whenever aspiration procedures have failed, or in the presence of foreign material or fungal abscess. Medical treatment is indicated for small and deeply located abscesses in patients with satisfactory clinical states. Empyemas in our series were treated with burr hole and pus aspiration. The mortality rate was 11%, and 62.5% of the patients made a good recovery. In agreement with other reported studies, the method of treating subdural empyema is much less significant than an aggressive early drainage of the infection. Although brain abscesses and empyema remain a significant neurosurgical concern, aggressive treatment can result in an excellent outcome in the majority of patients.

Cranial extradural empyema in the era of computed tomography: a review of 82 cases

OBJECTIVE

Intracranial suppurative disorders (abscesses and empyemas) continue to be common neurosurgical emergencies in South Africa. Cranial extradural empyema (EDE) occurs less frequently than its subdural counterpart but remains a potentially devastating disease process. We present our 15-year experience with this condition in the era of computed tomography.

METHODS

Of the 4623 patients with intracranial sepsis who were admitted to the neurosurgical unit at Wentworth Hospital (Durban, South Africa) during a 15-year period (1983-1997), 76 patients with EDEs were identified. An additional six patients who were identified from our outpatient records were treated nonsurgically. Analyses were performed with respect to clinical, radiological, bacteriological, surgical, and outcome data. All information for this study was obtained from the computerized databank for the unit. Statistical analyses of the related pre- and postoperative clinical data were performed.

RESULTS

The 76 patients with EDEs accounted for 1.6% of the total number of patients admitted for treatment of intracranial sepsis during the study period. Thirteen patients (15.8%) had infratentorial pus collections. Male patients predominated by a ratio of 2:1, and 66 patients were between the ages of 6 and 20 years (mean age, 16.56+/-9.87 yr). The origins of the sepsis were paranasal sinusitis for 53 patients (64.6%), mastoiditis for 16 patients, trauma for 5 patients, dental caries for 1 patient, and miscellaneous causes for 7 patients. The most common clinical presenting features were fever, neck stiffness, and periorbital edema. Surgery was performed in the form of burrholes for 21 patients, small craniectomies for 39 patients, and craniotomies for 5 patients. The additional five patients, while having drainage of their infected paranasal sinuses, had simultaneous drainage of their extradural pus collections by the ear, nose, and throat surgeon. The majority of patients (81 patients) experienced good outcomes (Glasgow Outcome Scale scores of 4 or 5). A single patient died after surgery (mortality rate, 1.22%).

CONCLUSION

EDEs occur less frequently than subdural empyemas and are associated with better prognoses. Surgical drainage (burrholes), simultaneous eradication of the source of sepsis, and high-dose intravenous antibiotic therapy remain the mainstays of treatment. Selective nonsurgical management of small EDEs is possible, provided the source of sepsis is surgically eradicated. It is our opinion that EDE is a disease that should be managed without morbidity or death.

Infratentorial subdural empyema, pituitary abscess, and septic cavernous sinus thrombophlebitis secondary to paranasal sinusitis: case report

OBJECTIVE AND IMPORTANCE

Infratentorial empyema, pituitary abscess, and septic cavernous sinus thrombophlebitis are all rare and potentially lethal conditions. The occurrence of all three in a single patient has not previously been described. We present such a case occurring in a young, otherwise healthy man.

CLINICAL PRESENTATION

A 26-year-old man with a remote history of sinusitis developed rapidly progressive headache, fever, right eye pain, swelling, proptosis, and visual impairment. Magnetic resonance imaging demonstrated diffuse pansinusitis, including sphenoid sinusitis, and extension of inflammation and infection into the adjacent cavernous sinuses, pituitary gland, and posterior fossa.

INTERVENTION

Urgent drainage of the ethmoid and maxillary sinuses was performed; pus was not identified. The patient continued to deteriorate clinically with worsening of visual acuity. Computed tomography of the head performed the next day revealed worsening hydrocephalus and an enlarging posterior fossa subdural empyema. Urgent ventricular drainage and evacuation of the empyema was performed, and subsequently, the patient's clinical course improved. The microbiology results revealed alpha hemolytic streptococcus and coagulase-negative staphylococcus species. The patient survived but during the follow-up period had a blind right eye and pituitary insufficiency.

CONCLUSION

Paranasal sinusitis can have devastating intracranial sequelae. Involvement of the adjacent pituitary gland and cavernous sinuses can result in serious neurological morbidity or mortality, and retrograde spread of infection through the basal venous system can result in subdural or parenchymal brain involvement. A high index of suspicion and aggressive medical and surgical treatment are crucial for patient survival, but the morbidity rate remains high. Our patient survived but lost anterior pituitary function and vision in his right eye.

Intracranial subdural empyemas in the era of computed tomography: a review of 699 cases

OBJECTIVE

Intracranial empyemas are the most common form of intracranial suppuration seen in our unit and, despite modern antibiotic therapy and advanced neurosurgical and imaging facilities, these pus collections remain a formidable challenge, often resulting in significant morbidity and death. We present an analysis of our 15-year experience with this condition in the era of computed tomography.

METHODS

A retrospective analysis of 4623 patients admitted with intracranial sepsis during a 15-year period (1983-1997) identified 699 patients with intracranial subdural empyemas. The inpatient notes for these patients were analyzed with respect to clinical, radiological, bacteriological, surgical, and outcome data. Statistical analyses were performed.

RESULTS

The 699 intracranial subdural empyemas accounted for 15% of all admissions for intracranial sepsis during the study period. Young male patients in the second or third decade of life were most commonly affected (62%), and the mean age was 14.65+/-12.2 years. Almost all patients (96%) underwent surgery. Eighty-two percent of patients experienced good outcomes (Glasgow Outcome Scale scores of 4 or 5). A morbidity rate of 25.9% (including postoperative seizures) was noted, and 85 patients died (mortality rate, 12.2%).

CONCLUSION

Intracranial subdural empyema, which is a neurosurgical emergency, is rapidly fatal if not recognized early and managed promptly. Early surgical drainage, simultaneous eradication of the primary source of sepsis, and intravenous administration of high doses of appropriate antibiotic agents represent the mainstays of treatment.