Intraventricular fat-fluid level secondary to rupture of an intracranial dermoid cyst

Microscopic and neuroendoscopic treatment of a large ruptured supratentorial dermoid cyst with extensive dissemination: a case report and literature review

Introduction and importance

Intracranial dermoid cysts are rare, constituting 0.04% to 0.6% of all intracranial tumors. They often arise from ectodermal cells trapped during neural tube formation. We report a case of spontaneous rupture of a large tentorial epithelioid cyst, which caused massive dissemination of liquid cholesterol into the subarachnoid cisterns and ventricles.

Presentation of case

A 28-year-old male presented with a two-week history of headache and memory decline. CT and MRI revealed a 9x6 cm lesion in the left frontotemporal region with widespread dissemination of lipid droplets. Surgical resection was performed using a microscope combined with a neuroendoscope. Pathology confirmed a dermoid cyst.

Clinical discussion

Ruptured dermoid cysts can cause significant symptoms due to the dissemination of cyst contents. Imaging is crucial for diagnosis and surgical planning. The combined microscopic and neuroendoscopic approach minimized blind spots and allowed thorough tumor exposure, facilitating complete resection with minimal residual complications. Postoperative outcomes were favorable, with imaging confirming substantial tumor removal and restored cerebrospinal fluid circulation.

Conclusion

Prompt diagnosis and comprehensive surgical intervention are essential for managing ruptured intracranial dermoid cysts. Combined microscopic and neuroendoscopic techniques are effective in achieving extensive resection and reducing complications.

Intracranial Transthecal Fat Migration After a Sacral Fracture: 2 Case Reports

BACKGROUND The presence of fat droplets within the subarachnoid space is an uncommon finding, which is almost exclusively associated with a ruptured dermoid cyst. In a trauma setting, transthecal migration of fat droplets is an extremely rare occurrence. We present 2 case reports of intracranial transthecal migration of fatty bone marrow after sacral fractures. CASE REPORT Both patients presented to the Emergency Department (ED) after falls from a standing height. The first patient, an 84-year-old woman, suffered a stable sacral fracture extending into a large meningeal cyst within the right S2 foramen. Her initial neurological assessment and computed tomography (CT) of the head were unremarkable. As the fracture did not require surgical treatment, she was discharged home and prescribed bed rest, analgesics, and venous thromboembolism prophylaxis. Three days after the injury, she was readmitted to the ED with a mild headache, dizziness, and an episode of nausea and vomiting. A follow-up head CT revealed fat droplets in the subarachnoid space and lateral ventricles. After successful symptomatic treatment, she was discharged home in good general condition. The second patient, a 60-year-old man, underwent a head CT for a scalp hematoma, which revealed fat droplets in the 3rd ventricle and right lateral ventricle. The pelvic CT revealed a large sacral meningeal cyst with microfractures in its wall. He was discharged home on the same day and prescribed bed rest and analgesics. CONCLUSIONS The detection of intracranial intrathecal fat droplets in association with a specific trauma mechanism should initiate the search for a sacral fracture.

Persisting Intraventricular Fat-Fluid Levels following Surgery on a Ruptured Dermoid Cyst of the Posterior Fossa

Intracranial dermoid cysts occasionally rupture spontaneously into the ventricles or into the subarachnoid space. In such cases, intraventricular fat-fluid levels are invariably evident at computed tomography and may even be visible on a conventional radiograph of the skull. A case is described in which fat was observed to remain in the ventricles long after surgical removal of a dermoid cyst. We think that this fat, by causing obstruction of the cerebrospinal fluid pathways, should be regarded as a potential cause of intermittent elevation of intracranial pressure.

Ventriculoperitoneal shunt malfunction caused by proximal catheter fat obstruction

Ventriculoperitoneal (VP) shunt placement is the mainstay of treatment for hydrocephalus, yet shunts remain vulnerable to a variety of complications. Although fat droplet migration into the subarachnoid space and cerebrospinal fluid pathways following craniotomy has been observed, a VP shunt obstruction with fat droplets has never been reported to our knowledge. We present the first reported case of VP shunt catheter obstruction by migratory fat droplets in a 55-year-old woman who underwent suboccipital craniotomy for removal of a metastatic tumor of the left medullocerebellar region, without fat harvesting. A VP shunt was inserted 1month later due to communicating hydrocephalus. The patient presented with gait disturbance, intermittent confusion, and pseudomeningocele 21days after shunt insertion. MRI revealed retrograde fat deposition in the ventricular system and VP shunt catheter, apparently following migration of fat droplets from the fatty soft tissue of the craniotomy site. Spinal tap revealed signs of aseptic meningitis. Steroid treatment for aseptic "lipoid" meningitis provided symptom relief. MRI 2months later revealed partial fat resorption and resolution of the pseudomeningocele. VP shunt malfunction caused by fat obstruction of the ventricular catheter should be acknowledged as a possible complication in VP shunts after craniotomy, even in the absence of fat harvesting.

Ectopic ventricular recurrence of an epidermoid cyst in the middle fossa

We present the first case of ectopic ventricular recurrence of an epidermoid cyst in the middle fossa with confirming histological characteristics. A 51-year-old woman presented with an epidermoid cyst in the middle fossa and underwent complete resection. On the 6-month surgical follow-up MRI, a nodular lesion was detected in the frontal horn of the left lateral ventricle without evidence of recurrence at the primary site. The patient underwent transcortial tumor resection. Results of histological studies confirmed that the lesion was an epidermoid cyst similar to the primary lesion. This is a case report of the cerebrospinal fluid spread of an epidermoid cyst, which strengthens the case for special care at the time of surgery to prevent spread of the lesion.

Traumatic rupture of an intracranial dermoid cyst

This paper reports the first case in which an intracranial dermoid cyst that underwent traumatic rupture was treated surgically and discusses the importance of the preoperative radiological identification and management of the rupture. For adequate management of a ruptured intracranial dermoid cyst, in addition to early surgery, we emphasize the importance of expeditious identification of the rupture with MRI, including an additional fat-suppression sequence, and prompt management of the accompanying chemical meningitis with intravenous steroid therapy beginning from the pre-operative period.

Ruptured intracranial dermoid: an unusual cause of headache in an older patient

A 76-year-old woman with a history of migraine presented with worsening headache. Computerized tomography brain scan and magnetic resonance imaging brain scan showed the presence of fat globules in the cerebrospinal fluid space. This appearance was suggestive of ruptured intracranial dermoid. She recovered spontaneously. While headache is a known presentation of ruptured intracranial dermoid, the condition is unusual to present in older people.

Ruptured intracranial dermoid cysts

Rupture of intracranial dermoid cysts (RICDC) is a rare phenomenon. The mechanism of rupture, pathophysiology of fat in the ventricles and subarachnoid spaces, possible complications, and proper management of such conditions are proposed on the basis of a review of the literature and experience with two cases of ruptured intracranial dermoid cysts (One was in the pineal region, while another was in the fourth ventricle). It is concluded that rupture of intracranial dermoid cysts is usually spontaneous and non-fatal. Persistence of fat in the subarachnoid spaces postoperatively may last asymptomatically for years. Surgery is the only way to deal with these benign lesions. If the capsule is adherent to vital areas, incomplete removal is advised as recurrence and malignant transformation are unlikely to occur.

Dissemination of fat in CSF: a common finding following translabyrinthine acoustic neuroma surgery*

OBJECTIVES

Following translabyrinthine craniotomy the temporal bone defect is commonly obliterated using a free autologous fat graft. In this series the dura was put back in place but not closed primarily. As the fat graft remains in direct contact with the cerebro spinal fluid (CSF) there is potential for dispersal of fat within the CSF space. This paper aims to determine the frequency of such CSF fat dissemination and its clinical significance.

DESIGN

A retrospective review of translabyrinthine acoustic neuroma removal with free fat autograft obliteration of the temporal bone defect between the years 1997 and 2000.

SETTING

Tertiary referral oto-neurosurgical centre. Postoperative magnetic resonance (MR) imaging.

PARTICIPANTS

All translabyrinthine patients who had postoperative MR imaging were included. Twenty-six cases were identified. Age range was 13-70 years. Fourteen were male patients.

MAIN OUTCOME MEASURES

Evidence of CSF fat dissemination on MR and patients' clinical findings.

RESULTS

Twenty-two of the 26 scans (85%) demonstrated evidence of fat dissemination into the subarachnoid CSF spaces in the form of microemboli. The cerebellopontine angle was the most common site involved. No evidence of ventricular dilation or any other abnormality was noted. There was no relationship between the presence or extent of fat microembolization and the patients' clinical course.

CONCLUSIONS

This study suggests that free fat placed in temporal bone defects commonly migrate into the subarachnoid space and subsequently move around in these spaces. This is not associated with any complications such as hydrocephalus, meningitis or prolonged postoperative headache.

Ruptured intracranial dermoid cysts

BACKGROUND

Intracranial dermoid cysts are rare congenital neoplasms that are believed to arise from ectopic cell rests incorporated in the closing neural tube. The rupture of an intracranial dermoid cyst is a relatively rare event that typically occurs spontaneously. In the past it was believed that rupture is always fatal, a hypothesis that is not supported by more recently reported cases. The symptoms associated with rupture vary from no symptoms to sudden death.

METHODS

The present paper analyzes published cases of ruptured intracranial dermoid cysts in terms of their age profile and their clinical presentation and describes an additional case.

RESULTS

Analysis of published cases revealed headache (14 out of 44 patients; 31.8%) and seizures (13 out of 44 patients; 29.5%), to be the most common signs of rupture followed by, often temporary, sensory or motor hemisyndrome (7 out of 44 patients; 15.9%), and chemical meningitis (3 out of 44 patients; 6.9%).

CONCLUSION

Headache occurred primarily in younger patients (mean age 23.5 +/- 9.3 years), whereas seizures primarily occurred in older patients (mean age 42.8 +/- 11.3 years). The patients with sensory or motor hemisyndrome associated with rupture of an intracranial dermoid cyst showed a more homogeneous age distribution (mean age 38.4 +/- 23.5 years).

Accumulation of intraventricular fat in an intracranial epidermoid tumor: case report

OBJECTIVE AND IMPORTANCE

A fat component within the ventricles or subarachnoid space in fat-containing tumors such as an epidermoid or a dermoid has been observed in rare instances. However, there have been no reports regarding an increase in the size of such a fat component. We describe the case of an epidermoid tumor with intraventricular fat that showed an increase in size and amount.

CLINICAL PRESENTATION

A 26-year-old woman was admitted with headache and diplopia. Computed tomography and magnetic resonance imaging of the brain revealed a fat-containing suprasellar tumor and widespread fat globules in adjacent sulci and cisterns and within the frontal horn of the lateral ventricle.

INTERVENTION

The patient underwent a pterional craniotomy. Removal of the suprasellar tumor was nearly total. Histopathological examination revealed an epidermoid tumor. Sequential magnetic resonance imaging throughout the ensuing 65-month period revealed no evidence of tumor recurrence; however, the intraventricular fat remained and increased in size. The patient underwent surgery via the transcallosal approach at 69 months after the initial operation, and the presence of free-floating oily fat globules was confirmed.

CONCLUSION

In the case of a fat-containing tumor with free fat in the cerebrospinal fluid spaces, careful serial examination is necessary, with particular attention to the possibility of changes in size.

Lipoid meningitis due to aseptic necrosis of a free fat graft placed during neurotologic surgery

We present two unusual cases of aseptic postoperative lipoid meningitis resulting from necrosis of a free fat graft placed into a skull base craniotomy defect. Two patients underwent translabyrinthine resection of acoustic neuroma and received abdominal fat grafts to ablate the surgical defect. Both patients presented postoperatively with persistent cerebrospinal fluid (CSF) wound leak and severe headache. Computed tomography demonstrated hydrocephalus and widely dispersed intracranial fat droplets throughout the CSF circulation. Both patients ultimately required CSF diversion for management of persistent communicating hydrocephalus. The clinical and radiographic correlates of lipocephalus and lipoid meningitis are presented, and a review of free fat graft physiology is discussed.

Three-dimensional chemical shift-selective MRI of a ruptured intracranial dermoid cyst

We report a man with a ruptured intracranial dermoid cyst, suffering from headache, nausea, vomiting and a generalised seizure. MRI was performed before and 2 weeks after surgical resection. On T1-weighted images the tumour gave high signal, as did fatty material in the frontal and parietal brain sulci. Identification of this hyper-intense material as lipids was possible by chemical-shift-selective 3D gradient-echo imaging, which provided excellent contrast between the subarachnoid lipids and the adjacent normal brain, with a good spatial resolution. Possible complications of subarachnoid and intraventricular lipid particles after dermoid cyst rupture are discussed and the diagnostic value of 3 D chemical-shift-selective additional to conventional T-1-weighted spin-echo images in identification of even small amounts of fat is emphasised.

Agenesis and lipoma of corpus callosum. Case report

The agenesis and lipoma of the corpus callosum is a very rare association. We report the case of a 18-years old woman with rare epileptic seizures since the age of 6 years, normal neurological examination, as well as normal electroencephalogram. The brain computed tomography scanning and the magnetic resonance showed the lipoma and the agenesis of the corpus callosum.

Spinal dermoid cysts originating intracranial fat drops causing obstructive hydrocephalus: case reports

The authors report two cases of spinal dermoid cysts whose rupture originated the migration of free fat drops into the ventricles and intracranial subarachnoid spaces. In both cases the fat drops caused obstructive hydrocephalus, which represents a quite exceptional complication. Moreover, one of the cases is unique, since the finding of intracranial fat causing hydrocephalus considerably preceded the discovery of the spinal neoplasm. The authors suggest that the finding of intracranial fat in the absence of a local source makes the search for a intraspinal dermoid or epidermoid tumor mandatory.

Mobile sediment of CaCO3 grains inside the cyst of an intraventricular teratoma. Case report

The case of a 40-year-old woman with a mature cystic teratoma in the lateral ventricle is reported. An unusual mobile sediment of radiopaque material in the cyst was identified as grains of calcium carbonate. It was considered to have precipitated from the cystic fluid under specific chemical conditions.

Ruptured supratentorial dermoid cysts

Two cases with ruptured supratentorial dermoid cysts are presented. Computerised tomography and magnetic resonance findings are illustrated. The pathology and differential diagnosis is discussed.

Ruptured suprasellar dermoid cyst presenting olfactory delusion (Eigengeruchs erlebnis)

A 24-year-old man sought treatment of a long-standing olfactory delusion (Eigengeruchs erlebnis) and associated psychotic symptoms, which disappeared after the removal of a suprasellar dermoid cyst. The pathophysiology of the phenomenon is discussed.

Intraventricular fat from a ruptured sacral dermoid cyst: clinical, radiographic, and pathological correlation. Case report

The authors report a unique case of a dermoid cyst that ruptured into the lumbosacral subarachnoid space following trauma, resulting in dissemination of cyst contents into the ventricles and cerebrospinal subarachnoid spaces. An intraspinous source should be considered when intraventricular fat is identified without a clear intracranial source.

Ruptured dermoid tumor of the cavernous sinus associated with the syndrome of fat embolism. Case report

The syndrome of fat embolism is a well-known clinicopathological entity that may appear 2 to 4 days after skeletal trauma; nontraumatic causes have been recognized, however. This report details the fat embolism syndrome occurring in a patient after surgery within the cavernous sinus to remove a dermoid tumor.

Supratentorial dermoid cysts

Supratentorial dermoid cysts are rare lesions. In eight cases presented here, the lack of recurrence after subtotal removal of the capsule and the good long-term prognosis are emphasized. This finding is in agreement with the literature. The frequent relationship of these lesions with the cavernous sinus suggests a vascular genesis in the development of intracranial dermoid cysts.

CT and MRI of ruptured intracranial dermoids

Two patients with ruptured intracranial dermoids, examined with both CT and MRI are reported. Clinical presentation was transient cerebral ischemia in one patient and acute meningeal signs in the other. CT scan showed typical fat density of the tumor and the subarachnoid space. On MRI both the tumor and the subarachnoid fat, were strongly hyperintense on T1-weighted images.

Cranial and spinal tumors with meningitic onset

We review the literature on cases of cranial or spinal tumor presenting with meningitic symptoms. Embryonal tumors-dermoid cysts, epidermoid cysts, craniopharyngiomas, teratomas-and malignant gliomas were the cause of most of the episodes of chemical meningitis, single or multiple in patients with no neurological symptoms. Differential diagnosis from aseptic meningitis, especially from Mollaret aseptic meningitis, is essential.

Craniocerebral epidermoids and dermoids. A review of 44 cases

We review 40 epidermoids and 4 dermoids of the skull and brain treated surgically in our Department between 1976 and 1987. Fourteen were extradural and 30 intradural. The mean duration of symptoms was 3 years for extradural and 10 years for intradural tumours. Symptoms varied with tumour site, in some sites being helpful in differential diagnosis. Skull X-rays and CT were the key diagnostic investigations in extradural and CT in intradural lesions, the latter, with few exceptions, presenting a characteristic CT scan. In 7 cases MRI supplied important details on the tumour boundaries. All the diploic and orbital lesions were removed totally, with a good outcome. Twelve of the intradural lesions were removed totally, 9 subtotally and 9 partially, with a good outcome in 21 patients and a poor outcome in 4; 5 patients died. Outcome was unrelated to degree of removal.

Rapid development of occlusion hydrocephalus by intraventricular fat possibly derived from a ruptured dermoid cyst

Images

The diagnosis of ruptured intracranial dermoid cysts

We present a case of a spontaneous asymptomatic rupture of an intracranial dermoid cyst with CT and MR images. The literature on the subject is reviewed. The potential associated complications are discussed.

Epidermoid tumors. Review of the literature

Reports of epidermoid tumors from 1965 through 1986 were reviewed with emphasis on new and unusual findings. Clinical data considered were rapid onset, rare symptoms, size and rate of growth, and complications. Uncommon locations included multiple sites in one patient and the anterior fontanelle. The radiologic data from computed tomography were the main contributors to diagnosis. An immunohistochemical test disclosed that cells of craniopharyngiomas are keratin-positive. Histologically benign epidermoids can behave as highly malignant tumors, and can become carcinomatous. Postoperative results for benign tumors were often excellent. Evidence was presented of the close relation among epidermoid and dermoid tumor, craniopharyngioma, ameloblastoma (adamantinoma), Rathke's cleft cyst, and aural cholesteatoma.

Febrile convulsions in an adult as presenting symptom of intracranial dermoid cyst: a case report

A 32-year-old man had generalized tonic-clonic epileptic seizures associated with episodes of recurrent high fever for 6 years. Repeated physical examinations including neurological status, EEG and nuclear brain scan were negative. Brain CT showed a non-homogeneous parasellar cyst of low density and fat-fluid levels in the lateral ventricles. The diagnosis of intracranial dermoid cyst was confirmed at surgery and histopathologically. Recurrent febrile convulsions and chemical meningitis may be the only clinical manifestations of ruptured dermoid cyst. The CT features of intracranial dermoid cyst are pathognomonic.

NMR imaging of congenital intracranial germinal layer neoplasms

NMR images in five patients with surgically proved, congenital germinal layer intracranial neoplasms (two dermoid and three epidermoid tumors) were reviewed. The dermoids were typically midline (suprasellar or parapineal) masses with sharply-defined margins. Relaxation times were variable, but if fat was present, T1 was decreased, and T2 was increased. The epidermoids were off the midline (cerebellopontine angle, temporal lobe, frontal lobe) masses with generally long T1 and T2 relaxation times. Obstructive hydrocephaly was noted in one patient, and tumor to ventricular communication was demonstrated in another.

Demonstration of postural effects and layering by cranial computed tomography

The superb contrast resolution of computed tomography permits visualization of layering of fluid components of varying densities in tumors and hematomas which cannot be observed with conventional radiographic techniques. Layering confirms the fluid nature of a cystic tumor and suggests the possibility of draining the fluid contents in an effort to reduce mass effect. Verification of layering is achieved by noting shifting of the dependent material with axial rotation of the patient. While unusual, this finding is significant because solid tumors occasionally show low densities simulating fluid. The presence of layering of intraventricular of subdural blood implies that the blood is fluid rather than clotted and therefore removal by aspiration will be possible.

Diagnosis by computerized tomography of intradural dermoid with spontaneous rupture of the cyst

Two cases of para- and suprasellar dermoid cysts are presented. The specific CT findings for this tumour are demonstrated: very low absorption values below minus 40 EMI units, variable densities in the cyst content, shell-like annular calcifications, and absent central enhancement effect. Spontaneous perforation of the cyst with dissemination of dermoid material into the CSF spaces is shown. The differential diagnosis from other low density lesions (epidermoid, cystic craniopharyngioma, arachnoid cyst) is discussed.

Radiolucent intracranial dermoid Cyst. Report of an unusual case

An intracranial dermoid cyst presenting as a radiolucent mass on the plain radiographs of the skull is described.

Spontaneous rupture of a pineal teratoma

A case of a spontaneously ruptured pineal teratoma is presented. This was diagnosed by computed tomography (CT) and was confirmed later at operation.

Low attenuation lesions in the midline posterior fossa: differential diagnosis

A wide variety of cystic appearing or low attenuation lesions in the midline posterior fossa can so closely resemble one another as to render specific histologic diagnosis from CT scans alone fraught with error. Absorption coefficients often overlap and are too nonspecific to infer consistently accurate histologic diagnosis. It is virtually impossible to separate cystic from noncystic, benign from malignant, and neoplastic from non-neoplastic lesions by absorption coefficients alone.

Preoperative diagnosis of a ruptured intracranial dermoid cyst by computerized tomography. Case report

A case of ruptured intracranaial dermoid cyst in the right middle fossa is reported. A definitive diagnosis of the lesion and the fact that it had ruptured was made possible by specific computerized tomographic findings. The findings were confirmed at surgery.

Computerized cranial tomography of free intracranial fat in congenital tumors

Three additional cases of free intracranial fat associated with congenital tumors are reported. The migration of fat with positional change is detailed. Free intraventricular fat may present without transcerebral rupture of the tumor. Our experience with these three patients, plus the two previously reported, suggest that two conditions must be present for oily material to enter the ventricular system through the outlets of the fourth ventricle: first, there must be a reversal of bulk flow of cerebrospinal fluid; second, the oily material must have a specific gravity less than that of cerebrospinal fluid. Also noted from our series is the absence of serious clinical sequelae associated with rupture or leakage of fatty tumors.