Endovascular treatment of mural-type vein of Galen malformations

OBJECT

In this study the authors report on the results of endovascular treatment for mural-type vein of Galen malformations (VGMs) in a group of infants.

METHODS

Eight children (six infants and two neonates) who suffered from symptoms caused by a mural-type VGM were treated by means of endovascular therapy. Their age at the time of treatment ranged from 13 days to 19 months (mean 7.6 months). Two neonates and three infants who presented with hydrocephalus and increased head circumference, one of whom was stabilized with a shunt, underwent elective closure of the malformations 3, 4, 6, 6, and 13 months later, respectively. Two patients presented with hemorrhage; one had an intraventricular hemorrhage (IVH) on the 1st day of life and one, a 5-month-old infant, suffered a large parenchymal hemorrhage and an IVH; both patients were immediately cured by means of endovascular techniques. One child presented with a seizure and cortical venous drainage that were treated immediately. Eleven separate treatment sessions were conducted; eight via transarterial femoral access and the remaining three via a transvenous approach. Two patients were treated by using transfemoral transvenous embolization with fibered coils, and one patient required a transtorcular transvenous approach to permit complete closure of the fistula with electrolytically detachable coils. The embolic devices used included silk suture emboli (three patients), electrolytically detachable coils (three patients), and fibered platinum coils (seven patients). In seven patients, complete closure was demonstrated on postembolization arteriographic studies. The eighth patient had stagnant flow in a giant 6-cm varix treated with arterial and venous coils but has not yet undergone follow-up studies. Late follow-up arteriography was performed in four patients at times ranging from 11 to 24 months postprocedure. In one patient, thrombosis of the malformation and shrinkage of the varix were confirmed on follow-up computerized tomography scanning. The remaining three patients have not yet undergone follow-up angiographic examination. Two asymptomatic complications occurred, including separation of the distal catheter, which was removed with a snare device, and a single platinum coil that embolized to the lung, producing no symptoms in 101 months of clinical follow up. The follow-up period ranged from 3 to 105 months, with a mean of 52 months.

CONCLUSIONS

Endovascular therapy is the treatment of choice for mural-type VGMs and offers a high rate of cure with low morbidity.

Endovascular treatment of mural-type vein of Galen malformations

OBJECT

In this study the authors report on the results of endovascular treatment for mural-type vein of Galen malformations (VGMs) in a group of infants.

METHODS

Eight children (six infants and two neonates) who suffered from symptoms caused by a mural-type VGM were treated by means of endovascular therapy. Their age at the time of treatment ranged from 13 days to 19 months (mean 7.6 months). Two neonates and three infants who presented with hydrocephalus and increased head circumference, one of whom was stabilized with a shunt, underwent elective closure of the malformations 3, 4, 6, 6, and 13 months later, respectively. Two patients presented with hemorrhage; one had an intraventricular hemorrhage (IVH) on the 1st day of life and one, a 5-month-old infant, suffered a large parenchymal hemorrhage and an IVH; both patients were immediately cured by means of endovascular techniques. One child presented with a seizure and cortical venous drainage that were treated immediately. Eleven separate treatment sessions were conducted; eight via transarterial femoral access and the remaining three via a transvenous approach. Two patients were treated by using transfemoral transvenous embolization with fibered coils, and one patient required a transtorcular transvenous approach to permit complete closure of the fistula with electrolytically detachable coils. The embolic devices used included silk suture emboli (three patients), electrolytically detachable coils (three patients), and fibered platinum coils (seven patients). In seven patients, complete closure was demonstrated on postembolization arteriographic studies. The eighth patient had stagnant flow in a giant 6-cm varix treated with arterial and venous coils but has not yet undergone follow-up studies. Late follow-up arteriography was performed in four patients at times ranging from 11 to 24 months postprocedure. In one patient, thrombosis of the malformation and shrinkage of the varix were confirmed on follow-up computerized tomography scanning. The remaining three patients have not yet undergone follow-up angiographic examination. Two asymptomatic complications occurred, including separation of the distal catheter, which was removed with a snare device, and a single platinum coil that embolized to the lung, producing no symptoms in 101 months of clinical follow up. The follow-up period ranged from 3 to 105 months, with a mean of 52 months.

CONCLUSIONS

Endovascular therapy is the treatment of choice for mural-type VGMs and offers a high rate of cure with low morbidity.

Endoscopic third ventriculocisternostomy: MR assessment of patency with 2-D cine phase-contrast versus T2-weighted fast spin echo technique

PURPOSE

To determine if fast spin-echo T2 (FSE) is of equal value to flow-sensitive 2D cine phase-contrast (CPC) to assess patency of endoscopic third ventriculocisternostomies (VC).

PATIENTS AND METHODS

We reviewed clinical charts and MR scans of 27 patients who underwent third VC for treatment of obstructive hydrocephalus. Thirty-nine postoperative scans included both sequences and were assessed for the presence or absence of flow-related signal changes.

RESULTS

In 28 cases, FSE, CPC, and clinical findings suggested patency. In 1 case, CPC and FSE suggested occlusion, which was confirmed clinically and operatively. In the remaining cases, FSE showed better clinical correlation than did CPC.

CONCLUSION

The assessment of third VC patency with FSE, a sequence available on most clinical scanners without a requirement for special hardware and software, is at least as sensitive in the qualitative assessment of VC function as CPC.

Primary intracerebral osteosarcoma: a case report

Primary intracerebral sarcomas are rare tumors. Malignant fibrous histiocytoma and fibrosarcoma are the predominant histologies. A 3 year old girl with a primary, intraparenchymal cerebral osteosarcoma, the second case reported in the literature, is described. Partial surgical resection, systemic chemotherapy and radio-surgery has provided tumor control at 18 months. Treatment issues are discussed.

Skull base and calvarial deformities: association with intracranial changes in craniofacial syndromes

PURPOSE

To analyze the skull and brain malformations in patients with craniofacial syndromes.

METHODS

A retrospective analysis of imaging studies of 21 children with craniofacial anomalies (8 with Apert syndrome, 6 with Pfeiffer syndrome, 4 with Crouzon syndrome, 1 with Robert syndrome, 1 with Coffin-Lowry-syndrome, and 1 with Saethre-Chotzen syndrome) was carried out using CT (21 patients), MR imaging (9 patients), and MR venography (2 patients). A series of qualitative and quantitative assessments of the skull base and intracranial structures was performed.

RESULTS

Skull base abnormalities were present in all patients. Intracranial abnormalities included ventriculomegaly, frank hydrocephalus, callosal anomalies, hypoplasia/absence of the septum pellucidum, hypoplasia/dysplasia of the hippocampus, dysplasias or distortions of the cerebral cortex, and parenchymal hemorrhage. The anomalies of the corpus callosum, septum pellucidum, and hippocampus appeared primary, whereas the others may have been the result of brain distortion by the calvarial anomaly. MR imaging was more useful than CT for evaluating brain abnormalities. In the two patients in whom it was performed, MR venography showed anomalies of the venous system, indicating that venous anomalies, possibly related to the skull base hypoplasia, may contribute to the intracranial abnormalities.

CONCLUSION

A wide range of neuroimaging abnormalities are present in the craniofacial syndromes. Some of these are clearly primary, whereas others appear to be related to the small skull base and sutural synostoses. MR venography may prove useful in defining the cause of some of the associated anomalies.

Gamma knife radiosurgery in children

52 pediatric patients were treated with radiosurgery at the University of California, San Francisco. Arteriovenous malformations were treated in 27 patients. Complete obliteration was noted in 4 of 12 patients imaged more than 2 years after radiosurgery. Arteriovenous malformation rebleed was noted in 1 patient. Symptomatic T2 changes were noted in 2 patients. Among 29 neoplasms treated in 25 patients, local control was noted in 5 of 7 low-grade gliomas, 5 of 14 high-grade gliomas, 4 of 5 craniopharyngiomas and 3 of 3 sarcomas. Three patients treated for neoplasms developed necrosis after radiosurgery.

Stereotactic insertion of an ommaya reservoir: technical note

BACKGROUND

Stereotactic insertion of catheters into deep-seated tumors or developmental cysts is easily accomplished, but connecting the catheter to an Ommaya reservoir while maintaining catheter position can be difficult. We describe a technique for easy placement of a catheter-Ommaya reservoir construct with one pass.

METHODS

Standard stereotactic imaging is performed. The distance from the outer table of the skull to the target point is measured. A catheter-Ommaya reservoir construct is assembled to this length and directed to the target position with a standard Cosman-Robert-Wells (CRW) stereotactic frame.

RESULTS

Use of this technique placed catheters into tumor or developmental cysts accurately and with no surgical complications in 12 patients.

CONCLUSIONS

This technique is simple, safe, reliable, and requires no special equipment. It avoids the risk of dislodging the catheter when it is being connected to the Ommaya reservoir, reducing the chances of cyst leakage and collapse.

Progression of multiple cryptic vascular malformations associated with anomalous venous drainage. Case report

The case of a young girl with a pericallosal venous malformation associated with multiple cryptic vascular malformations (CVM's) is described. The presenting cryptic malformation, which hemorrhaged, was completely excised, but the venous malformation was not. Routine follow-up magnetic resonance images obtained over the past 9 years have documented the development of multiple new cryptic malformations along the radicles of the venous malformation. Magnetic resonance imaging and cerebral angiography revealed venous outflow obstruction at the junction of the venous malformation with the straight sinus. The association of CVM's with anomalous venous drainage patterns and the role of venous hypertension in the pathogenesis of cryptic malformations are discussed. This case suggests that CVM's associated with a venous malformation may recur and new ones may develop if the venous malformation is not excised, particularly if venous hypertension is also present. The likelihood of a surgical cure in these patients may depend on complete excision of both anomalies, which is rarely feasible because of the potentially devastating results of resecting a venous malformation. Alternative treatments for patients with both types of lesions are discussed.

AIDS and the neurosurgeon--an update

Over the past decade, acquired immunodeficiency syndrome (AIDS) has become the leading public health crisis in the United States, Western Europe, and Africa. Despite improvements in the diagnosis and treatment of AIDS-related disorders, the number of people infected with the human immunodeficiency virus (HIV-1) continues to grow, requiring a greater proportion of limited financial, medical, and human resources. Since nearly one half of symptomatic AIDS patients have neuropathologic disease, clinicians must be aware of the myriad neurologic manifestations of AIDS and use the most effective methods to diagnose and treat them. The work-up of the AIDS patient with neurologic symptoms includes a careful history and physical examination, laboratory studies, and radiographic imaging. Gadolinium-enhanced magnetic resonance (MR) imaging has become the radiographic screening study of choice. MR imaging can be used to predict which patients should undergo stereotactic biopsy before an empirical trial of antitoxoplasmosis therapy. Any patient with a mass lesion that does not respond to empirical therapy for toxoplasmosis should also undergo biopsy to exclude another treatable disorder. While the number of patients with neurological complications can be expected to increase in the near future, better imaging techniques may obviate the need for biopsy in many of these patients. The increasing threat of HIV-1 infection in the workplace requires meticulous care both in and out of the operating room to minimize accidental exposure of health-care workers.

Focal brain-stem astrocytomas causing symptoms of involvement of the facial nerve nucleus: long-term survival in six pediatric cases

Six children with a history of isolated facial nerve dysfunction or dizziness and nausea were treated for brain-stem glioma between 1984 and 1992. Computerized tomography and/or magnetic resonance (MR) imaging showed a focal, uniformly enhancing mass involving the facial nerve nucleus of the pons. All patients underwent biopsy; the histological diagnosis was juvenile pilocytic astrocytoma in five cases. In the remaining case the biopsy was nondiagnostic, although the surgeon believed that the lesion was a glioma. Postoperatively, five patients underwent conventional focal megavoltage radiation therapy (180 to 200 cGy/day) over a period of 5 1/2 weeks to a total dose of approximately 5400 cGy. One child's family refused radiation therapy; she remained well and stable for 4 years, despite persistent facial weakness, and was eventually lost to follow-up review. Four irradiation-treated patients had complete resolution of their tumors on MR images and have had no evidence of neuropsychological or neuroendocrinological deficits during 4 1/2 to 8 years of follow-up evaluation. Patients whose neuroradiological studies show a lesion resembling those in this series should undergo biopsy and, if the histology of a low-grade tumor (in particular, a juvenile pilocytic astrocytoma) is confirmed, should then receive focal radiation therapy with conventional megavoltage dosages.

Pediatric cryptic vascular malformations: presentation, diagnosis and treatment

Since the advent of magnetic resonance (MR) imaging, angiographically occult or 'cryptic' vascular malformations (CVMs) have been detected with increasing frequency in the pediatric population. The natural history of these lesions is uncertain and treatment remains controversial. We respectively reviewed the presentation, radiology, treatment and outcome of 37 pediatric patients with CVMs seen at our institution between 1982 and 1992. MR imaging was diagnostic in all patients studied. Angiography was negative in 20 of 21 patients studied, while 1 teenage girl was found to have a venous malformation. Total surgical excision was the treatment goal in all patients presenting with symptomatic CVMs. There has been no surgical mortality. Perioperative complications occurred in one third of the patients but quickly resolved in most cases. Only 2 patients with multiple CVMs, including brainstem lesions, who presented with progressive neurologic deficits were clearly worse following surgery. Six of seven patients with radiation-induced CVMs have remained asymptomatic with close radiographic follow-up, while 1 patient with a hemorrhage has required surgical evacuation. We conclude that CVMs occur more commonly in the pediatric population than previously assumed. Patients presenting with seizures or hemorrhage should undergo craniotomy with the goal of complete excision. Radiation therapy plays no role in the treatment of these lesions and may actually result in their formation. Careful clinical and radiological follow-up is critical to assess the completeness of surgical removal and to evaluate progression of lesions in patients with multiple or radiation-induced CVMs treated conservatively.

Lumbar spinal stenosis

Lumbar spinal stenosis, the results of congenital and degenerative constriction of the neural canal and foramina leading to lumbosacral nerve root or cauda equina compression, is a common cause of disability in middle-aged and elderly patients. Advanced neuroradiologic imaging techniques have improved our ability to localize the site of nerve root entrapment in patients presenting with neurogenic claudication or painful radiculopathy. Although conservative medical management may be successful initially, surgical decompression by wide laminectomy or an intralaminar approach should be done in patients with serious or progressive pain or neurologic dysfunction. Because the early diagnosis and treatment of lumbar spinal stenosis may prevent intractable pain and the permanent neurologic sequelae of chronic nerve root entrapment, all physicians should be aware of the different neurologic presentations and the treatment options for patients with spinal stenosis.

Severity and outcome of intracranial lesions in pedestrians injured by motor vehicles

To evaluate the type and severity of intracranial lesions and the prognosis after closed head trauma in pedestrians injured by motor vehicles, we reviewed the cases of 225 consecutive patients who suffered major head injuries in collisions with motor vehicles. Patients in this series were comatose, had intracranial hematomas requiring surgical removal, or both. The initial Glasgow Coma Scale (GCS) score was 9-15 in 24% of patients, 6-8 in 32%, and 3-5 in 43%. Intracranial hypertension occurred in 40%. Diagnostic studies showed subdural hematomas in 45% of patients, epidural hematomas in 8%, intracerebral hematomas in 10%, and cerebral contusions in 9%. Clinically significant mass lesions were evacuated, and intracranial pressure was monitored and treated aggressively if elevated. After 6 months, 51% of the patients had died, 13% were vegetative or severely disabled, and 35% had a good outcome or moderate disability. These major head injuries in pedestrians struck by motor vehicles were usually severe, included a high incidence of intracranial hematomas and increased intracranial pressure, and frequently had poor outcomes.

Anomalous hypoxic acidification of medullary ventral surface

In castrated male goats, two flexible catheters, one open ended for reference and the other ending in a 1-mm-diam glass bulb pH electrode, were advanced ventrally through a left posterior fossa craniotomy into the subarachnoid space between the 9th and 10th cranial nerve roots, passing medially into cerebrospinal fluid (CSF) over the medullary ventral surface (MVS). They were anchored to dura and fascia, tunneled under the scalp, and terminated in connectors on the left horn. After several days for recovery, while the animals were awake, the effects of CO2 and hypoxia on pH of the film of CSF between the pia and arachnoid (pHMVS) were recorded along with end-tidal PCO2 and PO2 (mass spectrometer), ventilation (pneumotachometer) through a permanent tracheostomy, and, when possible, ear arterial O2 saturation (SaO2). High PCO2 acidified MVS as expected: delta pH MVS/delta log PCO2. = -0.64 +/- 0.14, producing a ventilatory response slope delta VI/delta pHMVS = 372 l/min. Hypoxia resulted in acid shifts even when PCO2 was allowed to fall. The development of hypoxic acidosis was related to the location of pH electrodes determined at necropsy. In isocapnic hypoxia, pH over putative chemoreceptor surfaces fell in proportion to desaturation: delta pHMVS = 0.0033(SaO2)-0.34, r = 0.80, Sy.x = 0.025. With uncontrolled arterial PCO2, similar acidosis occurred when SaO2 fell below 85-90%: delta pHMVS = 0.0039(SaO2)-0.34, r = 0.88, Sy.x = 0.032. With constant hypoxia, pH fell (tau = 3.7 +/- 2.2 min) to a plateau after 10-20 min and showed rapid recovery (tau = 2.0 +/- 1.3 min).(ABSTRACT TRUNCATED AT 250 WORDS)

Long experimental durations are required for double label [14C]- and [3H]2-deoxyglucose autoradiographic methods

Double-label 2-deoxyglucose (2-DG) studies using sequential [14C]- and [3H]2-DG injections demonstrate increased [14C]2-DG uptake during the first and second stimulation periods. To understand why this occurs, the rat mystacial vibrissae were stimulated at various times following [14C]2-DG injection. Local cerebral glucose utilization (LCGU) increased when whisker stimulation was performed at 0-90 min following [14C]2-DG injection. LCGU did not increase when whisker stimulation was performed at 90-150 min following [14C]2-DG injection. To minimize contamination of the two tracers in double label 2-DG mapping studies, the time between [14C]- and [3H]2-DG administration should be increased to 90 min.

Intracranial arachnoid cysts in children. A comparison of the effects of fenestration and shunting

The best operative intervention for children with arachnoid cysts remains the subject of controversy. Recent reports stress that craniotomy for cyst fenestration is associated with a low incidence of morbidity and mortality and may leave the child shunt-independent. The cases of 40 pediatric patients with arachnoid cysts treated between 1978 and 1989 are reported. Five children with mild symptoms and small cysts that remained stable on follow-up studies have not required surgical intervention. Of 15 patients with cysts initially treated by fenestration, 10 (67%) showed no clinical or radiographic improvement postoperatively and have undergone cyst-peritoneal (eight patients) or ventriculoperitoneal (VP) shunting (one patient), or revision of a VP shunt placed for hydrocephalus before cyst fenestration (one patient). Two other patients with existing VP shunts required no further procedures. Thus, only three (20%) of 15 patients initially treated by fenestration remain shunt-independent after a median follow-up period of 8 years. The 20 other patients were initially treated by cysts shunting and all improved postoperatively; shunt revision has been necessary in six (30%) of these 20 patients because of cysts recurrence. Cyst location influenced the success of shunt treatment; none of the seven middle cranial fossa cysts treated by shunting have required revision, but results with cysts in other locations were less favorable. In all locations, though, shunting was more successful than fenestration. It is concluded that cyst-peritoneal or cyst-VP shunting is the procedure of choice for arachnoid cysts in most locations, including those in the middle cranial fossa.

Use of CT and MR imaging to distinguish intracranial lesions and to define the need for biopsy in AIDS patients

To explore the potential usefulness of imaging studies in the diagnosis of focal central nervous system (CNS) lesions associated with acquired immunodeficiency syndrome (AIDS), the authors retrospectively examined the radiographic studies of 149 AIDS patients who presented with signs and symptoms of the three most common focal CNS lesions. Of these patients, 74 (50%) had Toxoplasma abscesses, 45 (30%) had primary CNS lymphoma, and 30 patients (20%) had progressive multifocal leukoencephalopathy (PML). Magnetic resonance (MR) imaging was more sensitive than computerized tomography (CT) in detecting lesions, especially in cases of PML. Whereas CT was unable to distinguish mass lesions caused by toxoplasmosis from those caused by lymphoma, 71% of the solitary lesions seen on MR images were lymphomas. These results indicate that empirical treatment for toxoplasmosis, the most common initial treatment for AIDS patients with neurological symptoms stemming from mass lesions, is not likely to be successful for patients with solitary lesions on MR images. Rather, early biopsy is advisable. If the presence of lymphoma is confirmed, the rapid initiation of treatment can allow prolonged high-quality survival.

Serial ultrasonographic evaluation of neonatal vein of Galen malformations to assess the efficacy of interventional neuroradiological procedures

Two-dimensional echocardiography complemented with color-flow imaging and pulsed Doppler ultrasound was used to evaluate one fetus and five neonates with a vein of Galen malformation who had severe high-output congestive heart failure and cranial bruits at birth. Intracranial blood flow through the vein of Galen malformations, cardiac status, and direction of aortic blood flow were assessed before and after staged interventional neuroradiological treatment with transarterial and transvenous embolization procedures. Color-flow imaging in each infant displayed the major vascular anatomy including feeding vessels and the patterns of filling of the vein of Galen malformations. Pulsed Doppler ultrasound performed on the descending aorta above the diaphragm showed the degree of diastolic flow reversal indicative of runoff into the vein of Galen malformations. A reduction in blood flow through the vein of Galen malformation was seen on color-flow imaging in four patients treated successfully by embolic procedures. The ratio of diastolic retrograde flow velocity in the descending aorta to systolic antegrade velocity decreased from 0.51 +/- 0.15 (mean +/- standard deviation) to 0.15 +/- 0.20 (P less than 0.05). Color-flow imaging and pulsed Doppler ultrasonography provided anatomical and pathophysiological information regarding cardiac hemodynamics and intracranial blood flow; with the patient's clinical status, these methods provided a reliable, noninvasive means to evaluate the effectiveness of therapy and the need for further treatment in neonates with vein of Galen malformations.

Interventional neuroradiological management of vein of Galen malformations in the neonate

Since 1978, the authors have seen 14 neonates with vein of Galen malformations who were born with severe congestive heart failure. The 5 infants treated before 1983 underwent craniotomy and clipping of feeding vessels; all died in the perioperative period. Since 1983, 8 neonates have been treated with combined arterial and venous interventional neuroradiological techniques; 6 infants survived. Two-dimensional echocardiography, color Doppler flow imaging, and pulsed Doppler ultrasound were used to assess blood flow within the malformation before and after staged transluminal embolic procedures were performed. The results of the diagnostic studies and the clinical status of the infants were used to evaluate the success of embolic therapy and the need for further neuroradiological intervention.

Neuroepithelial cysts of the posterior fossa. Case report

The authors report the case of a patient harboring a posterior fossa neuroepithelial cyst who presented with positional facial weakness and syncope. The patient recovered rapidly after cyst fenestration and placement of an internal cyst-cisternal shunt. The pathogenesis and principles of diagnosis and management of these rare lesions are reviewed.

Intracerebral arteriovenous fistulas associated with intraparenchymal varix in childhood: case reports

This report describes three children, each of whom developed an unusual malformation consisting of one or more intracerebral arteriovenous fistulas and a large intraparenchymal venous varix. Their clinical symptoms were similar to those produced by aneurysms of the vein of Galen: increasing head circumference, seizures, hemorrhage, and developmental delay. We treated each child with endovascular embolization and/or surgery and obtained complete closure of all fistulas without mortality.

Foramen magnum syndrome from pseudogout of the atlanto-occipital ligament. Case report

The authors report a case of progressive foramen magnum syndrome due to deposits of calcium pyrophosphate dihydrate crystals, which caused reactive hypertrophy in the posterior longitudinal ligament at C-1 and in the transverse ligament of the atlas in an 84-year-old woman. This is the first reported case of symptomatic pseudogout in this anatomic location. Rapid neurological recovery followed transoral decompression of the cervicomedullary junction.