Intracranial arachnoid cysts

PURPOSE

The purpose of this review article is to outline the natural history, pathogenesis, anatomic considerations and surgical decision-making in caring for patients with intracranial arachnoid cysts.

METHODS

A review of the literature for intracranial arachnoid cysts was performed using Embase, PubMed, and Web of Science databases, including review of the bibliographies of eligible articles and the author's own experience.

RESULTS

Among those reviewed, 59 relevant original articles were included as well as illustrative cases from the authors own experience.

CONCLUSIONS

Arachnoid cysts are congenital lesions characterized by split arachnoid membrane, thick collagen in the cyst wall, absent traversing trabecular processes within the cyst, and hyperplastic arachnoid cells in the cyst wall. The underlying etiology is not entirely known, and they occur in greater proportion in males and in greater incidence with various genetic conditions including Down syndrome, mucopolysaccharidosis, schizencephaly, neurofibromatosis, autosomal dominant polycystic kidney disease (ADPKD), acrocallosal syndrome, and Aicardi syndrome. Most intracranial arachnoid cysts are incidentally found and occur in the middle cranial fossa, with the remaining occurring in the cerebellopontine angle, suprasellar cistern, quadrigeminal cistern, convexity, and posterior fossa/cisterna magna. The current article outlines the natural history, prevalence, demographic factors, and treatment decisions in managing patients with intracranial arachnoid cysts.

Rare Case of Convexity Meningioma Growing into Arachnoid Cyst

BACKGROUND

Meningioma growing into an arachnoid cyst is an extremely rare event. Only 3 cases are reported in the literature. In 2 of them, an operative procedure in or near the arachnoid cyst preceded tumor growth.

CASE DESCRIPTION

We report a case of a patient requiring marsupialization of an arachnoid cyst of the middle cranial fossa. On follow-up, 3 years postoperatively he showed no signs of recurrence or tumor growth. One year later, the fourth year after surgery on the cyst, he presented with large tumor growth into the former cyst's cavity. Pathologic workup after resection revealed an atypical meningioma (World Health Organization grade II).

CONCLUSIONS

We discuss the possible pathogenesis in light of the scarce published literature, as well as the differential diagnosis of this rapidly growing tumor.

Development of Neuromyelitis Optica Spectrum Disorder and Spinal Arachnoid Cysts in a Patient With Intractable Epilepsy

Neuromyelitis optica is an inflammatory, demyelinating disease of the central nervous system that is characterized by severe relapsing attacks of optic neuritis and transverse myelitis. The current case describes a 29-year-old man with intractable epilepsy and diplegic spastic cerebral palsy who was given the diagnosis of neuromyelitis optica spectrum disorder after presenting with weakness, incontinence, and decreased visual acuity. His symptoms recurred 21 months after initial presentation. Magnetic resonance imaging of his spine revealed arachnoid cysts with regional mass effects. Differentiation of arachnoid cysts from a demyelinating process may be difficult in the early stages of the disease. Close monitoring of patients with neuromyelitis optica spectrum disorder is important, especially in patients with recurrent or refractory symptoms.

[Recurring post-traumatic growing skull fracture]

INTRODUCTION

Growing skull fracture, also known as post-traumatic bone absorption or leptomeningeal cyst, is a rare complication of traumatic brain injuries and occurs almost exclusively in children under 3 years of age.

CASE REPORT

We report the case of a 6-month-old child who presented, two months after an apparently unimportant traumatic skull injury, persistence of left temporoparietooccipital cephalohaematoma with no other signs. A transfontanellar ultrasonography scan revealed a bone defect with brain herniation, and computerised tomography and magnetic resonance imaging also confirmed the existence of a growing fracture. Excision of the leptomeningeal cyst, dural closure and repair of the bone defect with plates and lactate material were performed. Three months after the operation, the patient still presented collection of fluid and recurrence of the growing fracture was confirmed. Following the second operation, a baby helmet was fitted in order to prevent renewed recurrences. One year after the traumatic injury occurred, the patient remains asymptomatic.

CONCLUSIONS

Any child under 3 years of age with a post-traumatic cephalohaematoma should be checked periodically until the full resolution of the collection of fluid, especially if they present a fractured skull. The presence of a cephalohaematoma that remains more than two weeks after traumatic brain injury must make us suspect a growing fracture and reparation of the dura mater and a cranioplasty will be needed to treat it. The use of resorbable material allows it to be remodelled as the patient's skull grows, but its fragility increases the risk of recurrence. The use of a baby helmet after the operation could prevent complications.

[Intradural arachnoid cyst associated with syringomyelia: a case report]

An intradural arachnoid cyst is a relatively rare condition, occurring within the spinal subarachnoid space. We present the even-more rare case of an intradural arachnoid cyst associated with syringomyelia at the same spinal level. The patient was a 66-year-old man who presented with bilateral leg numbness and gait disturbance. Magnetic resonance imaging (MRI) revealed an intradural arachnoid cyst located dorsal to, and compressing, the thoracic spinal cord at the level of the 7th thoracic vertebra (Th 7). In addition, syringomyelia existed at the level of Th 8, slightly caudal to the intradural arachnoid cyst. We dissected the cyst but did not perform any surgical procedures for the syringomyelia. Post-operative MRI showed that the cyst had disappeared and the syringomyelia had spontaneously shrunk. The patient was discharged with improvement in his numbness and gait disturbance. There are a few case reports of intradural arachnoid cysts associated with syringomyelia, but recent evidence suggests that its occurrence is more common than previously thought. A combination of these two diseases is thought to be caused by blockage of cerebrospinal fluid (CSF) flow, which is also thought to cause adhesive arachnoiditis. For this reason, resection of the arachnoid cyst could improve the CSF flow and contribute to the shrinkage of syringomyelia. Furthermore, early treatment may correlate with improvement in radiological findings and neurological symptoms.

[An infant with acute subdural hematoma after a minor head injury associated with arachnoid cyst]

A ten-month-old male infant fell onto the floor from a chair of 50 cm in height and hit his head on the day before hospitalization. He was admitted due to acute subdural hematoma, which was associated with arachnoid cyst. Head CT conducted on the 4th day confirmed that the hematoma had not enlarged. After discharge, enlargement of the hematoma was detected on MR imaging conducted on the 65th day after injury, followed by the diminution without surgical treatment. MR images were obtained on the 192nd day. In the case of head injury associated with arachnoid cyst, the risk of subdural hematoma as well as its ensuing enlargement in subacute or chronic phase needs to be considered.

[Postraumatic epidural arachnoid spinal cyst: case report]

INTRODUCTION

Extradural arachnoid spinal cysts are unfrequent lesions that are associated with spinal trauma, surgery and less frequently with congenital anomalies. The clinical manifestations are similar to those seen with other compressive spinal cord lesions. Magnetic resonance techniques allow to diagnose correctly this pathology and to define its thopographic situation. The pathologic history of the patient is essencial to establish the ethiology. Surgery is the elective treatment in most cases.

CLINICAL CASE

The patient is a 35 years old man who has a medical history of penetrating spinal trauma two years ago. In that instance he suffered an unilateral spinal cord section at D2-D3 level with the corresponding Brown Sequard syndrome. A small wound was detected at the skin dorsal level and it was closed without difficulties. At the beginning, he improved his motor right leg function with rehabilitation and vitamins. After two years of good recovery he came to our hospital suffering a neurological deterioration of six months of evolution. The physical examination revealed an spastic paraparesis. Magnetic resonance was performed demonstrating a cystic extradural collection compressing the spinal cord at D3-D4 level. Surgical decompressive treatment allowed to excise the cyst and it was possible to define a dural tear that was closed successfully. The outcome was good with restoration of the initial motor function that he had after the spinal trauma.

CONCLUSIONS

Surgical management of postraumatic epidural arachnoid spinal cyst allows to detect the meningeal tear and to close it, which is highly effective on these kinds of lesions.

Intracranial arachnoid cyst

BACKGROUND

Arachnoid cysts (ACs) contain a liquid similar to cerebrospinal fluid. Some communicate with the subarachnoid space and others do not. These cysts are reported to account for at least 1% of all intracranial mass lesions. Most patients present during the first two decades of life; however, presentation during adulthood is not uncommon.

DISCUSSION

A literature review to identify studies relating to pathogenesis, epidemiology, genetics, presentation, radiology and treatment of ACs was conducted and indicated that symptoms depend on size and location. When ACs are symptomatic, they must be treated surgically. Surgical treatment of ACs can be accomplished by cystoperitoneal shunting or fenestration of the cyst either by craniotomy or endoscopic techniques.

CONCLUSIONS

Currently, appropriate treatment is still controversial regarding which is the best technique. Expectative treatment should be considered in lower volume cysts and, even more, in asymptomatic patients diagnosed by other studies.

Growing skull fracture in a 5-month old child: a case report

Growing skull fractures are a rare complication of linear skull fractures in children. The authors report a case of a growing skull fracture in a 5-month-old patient with a review of the literature. CT and MRI scans revealed a growing skull fracture with complication of leptomeningeal cyst formation. Surgical removal of the cyst, duraplasty and cranial reconstruction were performed. Follow up showed that the patient was stable neurologically and had improving left upper extremity weakness.

[A case of symptomatic arachnoid cyst, that had been growing for 14 years, at the posterior part of the left temporal lobe]

The authors report a 54-year-old woman with headache in whom a cyst was detected at the posterior part of the left temporal lobe following a traffic accident in 1993. Symptoms had recently worsened and computed tomography demonstrated an enlarged cyst in 2007. Thereafter, the patient underwent cyst fenestration. Intraoperative findings showed multilocular cysts with calcification. Symptoms improved immediately. Histological findings showed that the cyst was composed of collagenous membrane and a monolayer of cells compatible with arachnoid cyst. These findings also showed calcification and we considered that growth of the arachnoid cyst had been induced by trauma. We expected an arachnoid cyst with a single cavity, but this lesion was multilocular. Retrospectively, cine magnetic resonance image (MRI) seemed to show multilocular cysts. Cine MRI might be an effective tool to determine whether a cyst is multilocular.

Leptomeningeal cyst in a child after head trauma: a case report

BACKGROUND

Leptomeningeal cyst is an uncommon complication of paediatric skull fractures.

OBJECTIVE

To report a case of leptomeningeal cyst in a nine year old female.

METHODS

A nine-year-old girl presented with a 13 month history of recurrence seizures. Full clinical evaluation was undertaken. This was followed by radiological investigations.

RESULTS

The patient presented with a 13-month history of repeated seizures with no associated fever. The child had fallen from a one-storey building at the age of four years with temporary loss of consciousness and massive right sided head swelling but no radiological investigations were carried out at that time and she gradually recovered on conservative management. Physical examination showed a pulsatile depression on the right side of her head. Imaging studies confirmed this to be a leptomeningeal cyst, post traumatic cyst or growing fracture Conclusion: It is very important to carry out radiological investigations of all head injury patients no matter how subtle and to repeat such investigations especially when skull fractures are seen on initial investigations.

Post-traumatic leptomeningeal cyst mimicking a skull tumour in an adult

A 53-year-old female presented with a post-traumatic leptomeningeal cyst manifesting as bulging of the scalp, dizziness and tinnitus. She had known of the bulging of her forehead for about 20 years. She had suffered an injury to the head in childhood. Brain CT revealed a bone cyst associated with a round bone defect in the left frontal bone, bulging of the very thin outer layer and the defective inner layer. She was treated surgically with a diagnosis of skull tumour, but only gray cystic membranous tissue was found. The dural defect was repaired with fascia and the bone defect with bone cement. Bulging of the skull in adults can be caused by a bone cyst originating from a skull fracture.

Neuroimaging of traumatic brain injury

In this article, the neuroradiological evaluation of traumatic brain injury is reviewed. Different imaging strategies in the assessment of traumatic brain injury are initially discussed, and this is followed by a review of the imaging characteristics of both primary and secondary brain injuries. Computed tomography remains the modality of choice for the initial assessment of acute head injury because it is fast, widely available, and highly accurate in the detection of skull fractures and acute intracranial hemorrhage. Magnetic resonance imaging is recommended for patients with acute traumatic brain injury when the neurological findings are unexplained by computed tomography. Magnetic resonance imaging is also the modality of choice for the evaluation of subacute or chronic traumatic brain injury. Mild traumatic brain injury continues to be difficult to diagnose with current imaging technology. Advanced magnetic resonance techniques, such as diffusion-weighted imaging, magnetic resonance spectroscopy, and magnetization transfer imaging, can improve the identification of traumatic brain injury, especially in the case of mild traumatic brain injury. Further research is needed for other advanced imaging methods such as magnetic source imaging, single photon emission tomography, and positron emission tomography.

Symptomatic foraminal extradural meningeal cyst

The authors described the case of a 39-year-old man with Klippel-Trénaunay syndrome, who had an extradural meningeal cyst expanding into intervertebral foramen of lumbar 2 and 3 vertebrae. The patient suffered from low back pain radiating to the left lower extremity. Magnetic resonance imaging revealed a huge extradural meningeal cyst growing through intervertebral foramen far laterally. A widened neural foramen of L2 and L3 vertebrae was observed on his plain radiography. The cyst was totally excised after tying the ostium connecting the subarachnoid space of the dural sac. This case supports the congenital theory in the pathogenesis of spinal cysts because the Klippel-Trénaunay syndrome is a congenital disorder including a mesodermal abnormality which may be the causative factor for a congenital defect in dura.

A rare brain developmental anomaly in a patient with Usher's syndrome

We report a rare brain developmental anomaly in Usher's syndrome. We present a 43-year-old male with visual disturbance, hearing loss, and headache. Retinitis pigmentosa and sensorineural hearing loss were determined and he was diagnosed with Usher's syndrome according to the clinical findings. Magnetic resonance imaging showed an arachnoid cyst on the left temporal lobe, cavum septum pellucidum et vergae. Uneventful cataract surgery was performed in both eyes. He was suggested to be followed up periodically for the arachnoid cyst and to use a hearing device. Although auditory and visual disturbances are the typical findings of this syndrome, it may affect other parts of the central nervous system as well. Morphological abnormalities of central nervous system and related disorders can be seen in patients with Usher's syndrome.

Outcome of three cases of untreated maternal glutaric aciduria type I

We report, for the first time, the outcome of three children born to two women with untreated glutaric aciduria type I (GA I). Isolated hypocarnitinemia in neonatal screening in one baby allowed the identification of the disease in his mother, who was undiagnosed so far and had had a previous daughter. The other baby was born to an already diagnosed mother who was not treated; newborn screening in the child reflected the metabolic state of the mother. Biochemical abnormalities returned to normal within one week. At the age of 4 months, neuroimaging showed Sylvian enlargement in both infants and bilateral temporal arachnoid cysts in one. Physical and neurological developments were normal for the three patients at ages 2 and 5 years. We conclude that long-term follow up will determine the true impact of GA I in such children.

Intracranial arachnoid cysts: Current concepts and treatment alternatives

Arachnoid cysts are non-tumorous intra-arachnoid fluid collections that account for about 1% of all intracranial space-occupying lesions. In this article, we review the current concepts about these lesions and discuss the treatment alternatives. The aetiology of arachnoid cysts has been a controversial subject. They are regarded as developmental abnormality of the arachnoid, originating from a splitting or duplication of this membrane. The establishment of a single CSF space, by surgically communicating the cyst with the ventricular system or basal cisterns, appears to offer the best chance of a success in the treatment of arachnoid cysts. Long-term prognosis for patients with arachnoid cysts and well-preserved neurological conditions is good, even in the case of subtotal excision. Clinical follow-up and MRI allow earlier diagnosis of recurrence.

Posttraumatic intraventricular arachnoid cyst accompanied by pseudomeningoencephalocele in a child

Growing skull fracture (GSF) is a rare complication of head trauma. A posttraumatic intraventricular arachnoid cyst (AC), neither isolated nor accompanied by a GSF has not been reported previously. A seven-year-old girl was admitted after a severe head injury with a separated right parieto-occipital fracture and contusion. She responded well to conservative therapy. Seven weeks after discharge, she was re-admitted with a large parieto-occipital pseudomeningoencephalocele due to herniation of cerebrospinal fluid and neural tissue to the subgaleal space through the widened fracture defect, an extra-axial cyst at the posterior interhemispheric space and an intraventricular cystic mass. She underwent open surgery, and the intraventricular cystic mass was totally removed. The histological findings were consistent with an AC. One week after dural repair, hydrocephalus developed, and a ventriculo-peritoneal shunt was inserted. She did well during two-year follow-up. The present case is unique as an intraventricular AC following head trauma. When an intraventricular cystic lesion is encountered after severe head trauma, the possibility of an AC should be considered; especially with neighboring contused neural tissue and leptomeningeal cyst formation.

Proteus syndrome with syringohydromyelia and arachnoid cyst

INTRODUCTION

Proteus syndrome (PS) is a rarely seen, sporadic disorder with a wide range of abnormalities including asymmetrical overgrowth, skin lesions, dysregulated adipose tissue, and vascular malformations. Brain and spinal malformations are extremely rare; syringohydromyelia and arachnoid cyst have not been reported previously.

MATERIALS AND METHODS

We present a 5-year-old girl with PS having severe central nervous system (CNS) abnormalities demonstrated by magnetic resonance imaging (MRI) including craniocutaneous lipomatosis, hemimegalencephaly, arachnoid cyst, and syringohydromyelia.

Lumbar radiculopathy in ankylosing spondylitis with dural ectasia

We present a 57-year-old man with ankylosing spondylitis (AS) and significant dorsal lumbar dural ectasia (diverticulum). An L5 nerve root monoradiculopathy associated with AS has not been previously reported. The quantity and extent of such ectasia is variable but may be related to cauda equina syndrome. Long-term follow-up of these cases may reveal whether or not solitary nerve lesions gradually lead to cauda equina syndrome. We recommend that asymptomatic or symptomatic patients with dural ectasia should be closely observed without need for immediate surgical intervention.

A FORM OF DYSPLASIA OR A FORTUITOUS ASSOCIATION? A CEREBRAL ANEURYSM INSIDE AN ARACHNOID CYST

OBJECTIVE

Although arachnoid cysts and intracranial aneurysms are very common lesions, their association in the same patient is rare. We present a case of a middle cerebral artery aneurysm ruptured into an arachnoid cyst. We found only six cases with intracystic hemorrhage reported in the literature. The presence of an arachnoid cyst can mislead clinical presentation. The patient presented a paradoxically small temporal fossa and thickening of the temporal and sphenoid bone. The authors suggest that this uncommon association (arachnoid cyst, atypical cranial vault, and “mirror-like” cerebral aneurysm) could represent a form of dysplasia.

CLINICAL PRESENTATION

A 46-year-old patient presented with a 3-week history of slight headaches, which had worsened in the last 3 days before presentation. Computed tomographic scans showed a cystic lesion located in the middle cranial fossa and sylvian fissure with suspected aneurysm dilation inside. Magnetic resonance imaging scans showed an intracystic hemorrhage but not subarachnoid hemorrhage. Paradoxically, changes in the cranial vault around the cyst were noted. Digital subtraction angiography showed bilateral “mirror” middle cerebral artery aneurysms.

INTERVENTION

A large right pterional craniotomy was performed with full microsurgical removal of the arachnoid cyst walls and aneurysm clipping. The aneurysm was in the medial wall of the arachnoid cyst with its dome inside the cyst. The contralateral aneurysm was clipped 2 weeks later. The follow-up period was uneventful, and the patient returned to normal life.

CONCLUSION

Rupture of a cerebral aneurysm into an arachnoid cyst is rare. Clinical presentation may be unusual because the cyst can prevent subarachnoid hemorrhage. A middle fossa cranial arachnoid cyst in the presence of temporal bone depression, small middle fossa, and thickness of squamous temporal bone and the lesser wing of sphenoid is rare and suggests that congenital factors may play an important role in their development. The exceptional association between “mirror” aneurysms and arachnoid cyst with bone changes suggests a possible congenital form of dysplasia.

Neuroendoscopically assisted cyst-cisternal shunting for a quadrigeminal arachnoid cyst causing typical trigeminal neuralgia

A quadrigeminal cistern arachnoid cyst is a very rare cause of typical trigeminal neuralgia. A 62-year-old woman presented with right facial pain of 8 years duration. Neuroradiological findings revealed a cystic mass in the quadrigeminal region that compressed the cerebellum downward and the brainstem anteriorly and was associated with hydrocephalus. She had neuroendoscopically-assisted cyst-cisternal shunting via a small craniotomy. Postoperatively, the trigeminal neuralgia disappeared. The origin of the trigeminal neuralgia may have either been a marked distortion of the pons that caused stretching of the trigeminal nerve and irregular demyelination within the root entry zone, or there was contact between the root entry zone and a vascular structure. Neuroendoscopy is useful for treating arachnoid cysts; however, in order to safely relieve symptoms, the procedure needs to be appropriately adapted depending on the pathogenesis. In this paper, we review the literature and discuss the pathophysiology and treatment of our case.

[Non-haemorrhagic subependymal pseudocysts: ultrasonographic, histological and pathogenetic variability]

PURPOSE

Differentiation of non-haemorrhagic subependymal pseudocysts from subependymal pseudocysts after cerebral haemorrhage in the preterm infant.

MATERIALS AND METHODS

Selective ultrasonographic screening in 2200 neonates and retrospective analysis in 72 infants with subependymal pseudocysts, the full-term infants being analysed from birth, and the preterm infants after the second week of life, thus avoiding the gestational age at which cerebral haemorrhage occurs in the preterm infant.

RESULTS

Three variants of pseudocysts were identified: the caudothalamic germinolysis is a leukomalacic and pseudocystic gliosis. Pseudocysts in the anterior choroid plexus of the lateral ventricle could be distinguished from caudothalamic germinolysis by their location, form and movement. Pseudocysts lateral of the frontal horns are the result of regression of germinal matrix remains.

CONCLUSION

Differentiation of non-haemorrhagic from post-haemorrhagic germinolysis is necessary to clarify the aetiology and pathogenesis of non-haemorrhagic pseudocysts. Caudothalamic germinolysis possibly is the result of infection with stenotic intima proliferation following vasculitis. The results are thalamostriatal vasculopathy and germinal necrosis. Anterior plexus cysts might be the result of folding faults of the ependyma in the growth period of the choroid plexus. Pseudocysts lateral of the frontal horns should not be mistaken for ventricular ligaments.

Birth trauma and development of growing fracture after coronal suture disruption

INTRODUCTION

A growing fracture is a rare complication of skull fractures characterized by progressive diastatic enlargement of the fracture line. Growing skull fractures related to birth trauma were only occasionally reported. As far as we know, only one previous case of a neonatal growing fracture secondary to coronal suture disruption has been reported.

CASE REPORT

We present the case of a full-term infant born after a nontraumatic, forceps-assisted spontaneous delivery, who developed an increasing cystic swelling over the left frontoparietal area that crossed over coronal and sagittal sutures. The lesion was initially misinterpreted as cephalhematoma. Clinical and radiological follow-up established the correct diagnosis of leptomeningeal cyst.

OUTCOME

The collection was initially tapped. Surgical treatment was undertaken thereafter, consisting of decompression and resection of the cyst and dural repair. Two months after follow-up, the patient remains asymptomatic and the porencephalic cavity remains isolated from the extradural space, with no evidence of new fluid collections.

Spinal arachnoid cyst related to a nonaneurysmal perimesencephalic subarachnoid hemorrhage: case report

OBJECTIVE AND IMPORTANCE

We report the first case of a delayed symptomatic spinal arachnoid cyst related to a nonaneurysmal perimesencephalic hemorrhage. We review the literature concerning posthemorrhagic spinal arachnoid cysts.

CLINICAL PRESENTATION

A 64-year-old woman presented with progressive spinal cord compression symptoms 10 months after a nonaneurysmal perimesencephalic hemorrhage. Magnetic resonance imaging of the spine disclosed a dorsal and intradural cystic lesion producing posterior spinal cord compression.

INTERVENTION

A thoracic laminectomy allowed complete resection of the cyst. Surgical and histological findings disclosed an intradural arachnoid cyst. On postoperative follow-up, spinal magnetic resonance imaging confirmed satisfactory decompression of the spinal cord. Because of extensive arachnoiditis, the patient experienced only partial recovery from neurological deficits.

CONCLUSION

This extremely rare complication should be kept in mind when delayed lower-limb neurological deficits appear after subarachnoid hemorrhage, even in a perimesencephalic form.

Invasive Cerebrospinal Fluid Cysts and Cephaloceles of the Petrous Apex

OBJECTIVE

To describe the presentation, diagnostic evaluation, and surgical management of petrous apex cerebrospinal fluid (CSF) cysts and cephaloceles.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Six patients with symptomatic CSF cysts or cephaloceles.

INTERVENTION(S)

All patients underwent operative intervention.

MAIN OUTCOME MEASURE(S)

Presentation, imaging characteristics, operative findings, surgical approach, resolution of symptoms, and complications.

RESULTS

Six patients presented with various neurotologic symptoms including vertigo, otalgia, diplopia, meningitis, hearing loss, and retroorbital headaches. Four lesions were centered within the anterior petrous apex and were classified as a cephalocele originating from Meckel's cave. The remaining two lesions were arachnoid cysts that involved the posterior petrous apex. Cysts and cephaloceles both demonstrated bone erosion on computed tomography and were hyperintense on T2-weighted magnetic resonance imaging and isointense or hypointense on T1-weighted magnetic resonance imaging. A variety of surgical approaches was used to treat these lesions. Preoperative symptoms were improved in five of six cases. One patient developed a postoperative CSF leak that resolved with conservative measures.

CONCLUSION

Petrous apex CSF cysts and cephaloceles may present with a variety of neurotologic symptoms. Imaging often helps narrow the differential diagnosis, but these lesions can still be confused with other erosive skull base lesions such as cholesterol granulomas, epidermoids, or tumors. Optimal treatment of symptomatic posterior petrous apex CSF cysts is marsupialization via a posterior fossa approach (i.e., retrosigmoid or retrolabyrinthine). A middle fossa approach with obliteration of the anterior petrous apex may be used to treat symptomatic CSF cephaloceles arising from Meckel's cave.

New surgical approach for late complications from spinal cord injury

Background

The most frequent late complications in spinal cord injury result from arachnoiditis and consequent alterations in dynamics of cerebrospinal fluid flow. A surgical procedure carried out on patients with these alterations, resolved the various pathologies more efficiently in all cases.

Methods

From October 2000 to March 2006, 23 patients were selected for surgery: three showed signs of syringomyelia, three presented with microcystic lesions, three presented with arachnoid cysts in different locations but always confluent to the scar area, and 14 showed evidence of tethered cords. The surgery consisted of laminectomy at four levels, followed by dural opening in order to remove all the arachnoiditis at the level of the scar and to remove the altered arachnoid and its cysts, at least at two levels above and below the lesion. The dentate ligaments were cut at all exposed levels.

Results

The patients had no postoperative problems and not only retained all neurological functions but also showed neurological recovery. According to the motor and sensory scale of the American Spinal Injury Association, the recoveries were motor 20.6% (P < 0.001), touch 15.6% ((P < 0.001) and pinprick 14.4% (P < 0.001). These patients showed no signs of relapse at 4–66 month follow-up.

Conclusion

This alternative surgery resolved the pathologies provoking neurological deterioration by releasing the complete spinal cord at the level of the scar and the levels above and below it. It thus avoids myelotomies and the use of shunts and stents, which have a high long-term failure rate and consequent relapses. Nevertheless, this surgical procedure allows patients the chance to opt for any further treatment that may evolve in the future.

Cervicothoracic arachnoid cyst in a patient with neurofibromatosis: case report

Intradural cervicothoracic arachnoid cysts are not common. They may be congenital, or secondary to trauma, surgery, haemorrhage, or inflammation. This is a report of a 39-year-old man who presented with cutaneous neurofibromatosis and cervicothoracic arachnoid cyst causing gradual quadriparesis. Magnetic resonance imaging showed an intradural extramedullary anterior cystic lesion at C5-T2 level. Laminectomy and mersupialisation of the cyst was performed. Histology confirmed the diagnosis of arachnoid cyst. The patient recovered without neurological deficit.

Intracranial hypotension syndrome following chiropractic manipulation of the cervical spine

Cervical spine manipulation has been associated with several disorders such as cervical arteries dissection, but rarely has a relationship with intracranial hypotension been reported. We describe a patient showing intracranial hypotension syndrome following chiropractic cervical spine treatment. Magnetic resonance showed the presence of dural leakage at cervical level, suggesting the pathogenesis of the syndrome. We state that cervical spine manipulation should be considered a treatment with risk of neurological complications, including the occurrence of intracranial hypotension.

Post–dural headache associated with thoracic paravertebral blocks

The thoracic paravertebral block is effective in providing anesthesia and postoperative analgesia for thoracic and abdominal surgeries. This case report describes a suspected post-dural puncture headache following bilateral thoracic paravertebral blocks for postoperative analgesia after an umbilical hernia repair.

Quadrigeminal cistern arachnoid cyst in a patient with Kabuki syndrome

Kabuki syndrome is a rare dysmorphic disorder characterized by peculiar facial appearance, developmental delay, skeletal abnormalities, mental retardation, and dermatoglyphic abnormalities. Neurologic anomalies are frequently observed. This report presents a 2-year-old male with Kabuki syndrome who had a quadrigeminal cistern arachnoid cyst: the second case of such an association to be reported in the literature.

Spontaneous development of a de novo suprasellar arachnoid cyst

Arachnoid cysts are commonly thought to arise from either congenital defects or trauma. In this article the authors report the spontaneous development of a suprasellar third ventricular arachnoid cyst whose origin was not clearly congenital or traumatic. At the age of 4 months, the patient presented with hypertonia, and a magnetic resonance (MR) imaging study showed no abnormalities. At the age of 2 years, the boy presented with headaches and projectile emesis, symptoms that prompted further imaging studies. An MR image of the brain revealed a suprasellar cyst and obstructive hydrocephalus. The cyst was endoscopically fenestrated, which led to long-term symptom resolution.

Brucellar brain abscess and bilateral arachnoid cysts, unilaterally complicated by subdural haematoma

Arachnoid cysts are benign developmental cysts that occur along the cerebrospinal axis. Brucellar abscesses in the brain are relatively uncommon, with only a few cases reported in the literature. We report here a patient with a brucellar brain abscess and bilateral arachnoid cysts (one complicated with subdural haemorrhage), who was successfully managed with craniotomy and antibiotics.

Extradural spinal arachnoid cysts associated with spina bifida occulta

INTRODUCTION

Spinal extradural arachnoid cysts are an uncommon cause of neural compression in children. Even more uncommon is the association of such cysts with spina bifida occulta.

MATERIAL

Two girls, 12 and 8-years-old, presented with left leg pain, deteriorating gait, clinical signs of left L5 and S1 root compression, without bladder or bowel symptoms. The first patient had left foot drop. The second patient had muscle wasting and smaller left foot with pes cavus. Radiographs showed spina bifida occulta of S1 in both. MRI revealed an extradural cyst at the S1 level, indenting the thecal sac and the L5 and S1 roots. At operation in both patients a large arachnoid cyst arising from a small dural defect in the axilla of the left S1 root was compressing and displacing it and the dural sac. It was removed and the defect was repaired. The first patient improved with complete recovery of the foot drop. An MRI at 12 months showed no cyst recurrence. The second patient made good recovery initially, but at 10 months developed recurrent symptoms. An MRI scan showed recurrence of the cyst with root compression. On repeat exploration a different dural defect was identified in a more anterior position and was repaired.

DISCUSSION

The coexistence of extradural arachnoid cyst and corresponding bifid spinal segment has not been described previously. It raises the suspicion that the dural defect giving rise to the arachnoid cyst may be due to segmental dural dysgenesis in the context of the dysrhaphic neuroectodermal malformation.

Traumatic leptomeningeal cyst in a 24-year-old man: case report

OBJECTIVE AND IMPORTANCE

Traumatic leptomeningeal cysts represent a rare complication of a childhood cranial fracture, and occur in only 0.05 to 0.6% of all cranial fractures. In adults, clinical manifestations of a childhood trauma are very rare and usually appear in the form of nontender, nonpulsatile, subcutaneous mass, accompanied by a progressive neurological deficit and seizures, as shown in our case.

CLINICAL PRESENTATION

We present the case of a 24-year-old man with seizures caused by a traumatic leptomeningeal cyst resulting from the head injury he suffered at the age of 9 months.

INTERVENTION

Right-sided craniotomy was performed with consequent microsurgical removal of the leptomeningeal cyst. The dura was reconstructed in a watertight manner and a cranioplasty was performed with Palacos (Howmedica International, Limerick, Ireland).

CONCLUSION

It is important to consider traumatic leptomeningeal cysts when treating adult patients with erosive bone lesions who have a history of head trauma.

Arachnoid cyst with associated arachnoiditis developing after subarachnoid hemorrhage

✓ The authors report the case of a 53-year-old woman in whom a T1–T2 spinal arachnoid cyst with associated arachnoiditis developed, compressing the thoracic spinal cord 1 year after the patient had suffered a Hunt and Hess Grade IV subarachnoid hemorrhage (SAH). Development of spinal arachnoiditis with or without an arachnoid cyst is a rare complication of aneurysmal SAH. Risk factors may include posterior circulation aneurysms, the extent and severity of the hemorrhage, and the need for cerebrospinal fluid diversion. Surgical drainage, shunt placement, or cyst excision, when possible, is the mainstay of treatment.

Fronto-orbital leptomeningeal cyst manifested with exophthalmus

A 41-year-old female patient with fronto-orbital leptomeningeal cyst is presented. After decompression of the cyst, repair of bone and dura defects were achieved with autogenous bone grafts and pericranial flap. Our case was very interesting in several aspects: a head trauma at 3 years of age and manifestation of clinical symptoms (headaches and exophthalmia) after almost 4 decades that had been progressive for 6 months and a rare location (fronto-orbital region) that required a special management. A thorough history is crucial in such cases because clinical symptoms might appear after decades. An old fracture that is surrounded by thin calvarial tissue in conjunction with intracranial cystic formation should make one take a leptomeningeal cyst into consideration in differential diagnosis. Extensive dissection and adequate access osteotomies followed by repair with autologous and vascular tissues are the key factors for a successful outcome in the management of fronto-orbital pathologies.

Management of leptomeningeal malignancy

Leptomeningeal carcinomatosis is defined as malignant infiltration of the pia matter and arachnoid membrane. Leukaemias and lymphomas, lung, breast cancer and melanoma are the primary tumours commonly associated with leptomeningeal carcinomatosis. Diagnosis is based on compatible symptoms and signs, cytological evidence of malignancy in the cerebrospinal fluid, and neuroimaging studies. Treatment is largely palliative (median survival 2-4 months). Patients with lympomatous or leukaemic meningitis, chemosensitive tumours such as breast cancer, low tumour burden, minimal neurological deficits, good performance status and controllable systemic disease survive longer with occasional long-term responses. Available treatment options include focal radiation therapy to CNS sites of bulky, symptomatic or obstructive meningeal deposits, intrathecal cytotoxic therapy and systemic chemotherapy. No evidence of superiority of intrathecal treatment compared with best palliative care (including radiation therapy and systemic treatment) is available from clinical trials. Novel treatment approaches include intrathecal liposomal Ara-C, the development of new cytotoxic compounds, signal transduction inhibitors and monoclonal antibodies for intrathecal or systemic use. Until data from multi-centre randomised trials are available, rationalisation of therapy should be done by stratifying patients to prognostic groups. High-risk patients will only survive for a few weeks and are better managed with supportive measures, whereas low-risk patients justify vigorous cerebrospinal fluid-directed treatment combined with radiation therapy and systemic chemotherapy.

Acute lymphoblastic leukemia and posterior fossa arachnoid cyst in a five-year-old girl

The authors experienced a case of acute lymphoblastic leukemia whose leukemic karyotypes were associated with changes in chromosome 21 ploidy, and she was also found to have an arachnoid cyst in the posterior fossa. The association between arachnoid cyst and leukemia as described in the literature appear to be quite rare. The clinical and radiologic features of arachnoid cyst as well as cytogenetic abnormalities of the leukemic clones are described in the present article.

Brain stem glioblastoma with multiple large cyst formation and leptomeningeal dissemination in a 4-year-old girl

The authors report a 4-year-old girl who developed brain stem glioblastoma. Meningeal irritation was present at onset. Magnetic resonance imaging revealed intracranial and intraspinal leptomeningeal dissemination, which progressed faster than the original tumor. Multiple large cysts developed at the interhemispheric and prepontine cisterns, resulting in progressive obstructive hydrocephalus. The patient survived only 5 months after presentation. Histology was verified by autopsy.

Syringomyelia with Chiari malformation; 3 unusual cases with implications for pathogenesis

Syringomyelia is an important cause of neurological deficit. Most cases of non-traumatic syringomyelia occur in association with a Chiari malformation. We present three unusual examples of syringomyelia with such an association. The first case is that of syringomyelia in a young woman with Marfan's syndrome, a spontaneous CSF leak and intractable intracranial hypotension. The second is a woman with long-standing lumbo-peritoneal shunt for pseudotumour cerebri who developed an acquired Chiari malformation. A young woman with a Dandy-Walker cyst that herniated into the upper cervical canal is the third case. These cases provide a basis for discussion of the pathogenesis and management of syringomyelia and the Chiari malformation in such cases.

Leptomeningeal Cyst Development after Endoscopic Craniosynostosis Repair: Case Report

OBJECTIVE AND IMPORTANCE:

Endoscopically assisted (minimally invasive) craniosynostosis repair has been suggested as an alternative to traditional open craniosynostosis repair. Advocates of this approach assert advantages, including decreased blood loss, operative time, and hospital stay, while providing esthetic results and safety comparable with traditional open craniosynostosis repair. The difficulties inherent in endoscopic visualization may result in complications, however, that could temper enthusiasm for this procedure. The authors report a child in whom a leptomeningeal cyst developed after performance of endoscopic craniosynostosis repair, presumably from an iatrogenic dural laceration.

CLINICAL PRESENTATION:

A 5-month-old girl with sagittal synostosis underwent endoscopically assisted craniosynostosis repair. By report, the procedure was uneventful and the initial results were acceptable. The authors performed a chart review of their own experience with both endoscopically assisted craniosynostosis repair and traditional open repair.

INTERVENTION:

Five months after surgery, a pulsating forehead mass developed. Neuroimaging confirmed the diagnosis of a leptomeningeal cyst. The child was referred to our pediatric neurosurgery practice for operative repair. At the time of surgery, a dural defect lying directly under a previous osteotomy site was identified. After uneventful repair and follow-up of more than 1 year, the child is well and is without the development of a clinical seizure disorder or recurrence of her leptomeningeal cyst.

CONCLUSION:

Unrecognized dural injury combined with an overlying osteotomy in an infant can result in the development of a leptomeningeal cyst. Care must be taken at the time of endoscopic extradural surgery to recognize any inadvertent dural tears and to perform a direct repair at the time of the initial occurrence. Facility with and use of an appropriate endoscope is essential to the safe performance of minimally invasive craniosynostosis surgery.