Required Shunt Placement Research Articles

Surgeon Experience and CSF Shunt Outcomes

Source: Cochrane DD, Kestle JRW. The influence of surgical Cochrane DD, Kestle JRW. The influence of surgical operative experience on the duration of first ventriculoperitoneal shunt function and infection. Pediatr Neurosurg. 2003;38:295–301.In recent years there have been remarkable efforts to quantify the outcomes of frequently performed surgical procedures. These efforts have been driven by various professional, economic, and political forces, and they first addressed surgical enterprises that account for large health care expenditures, for instance, coronary artery surgery.1 Analytical eyes have now cast their gaze on the tiny field of pediatric neurosurgery and its most routine procedure, cerebrospinal fluid (CSF) shunt insertion.The Canadian provincial health plans issue all subscribers —essentially the entire population of Canada —a unique health care number that allows tracking of all insured medical services by patient as well as by provider and facility. Data from inpatient services in most provinces find their way to a repository at the Canadian Institute for Health Information. The previous experiences of institutions and of individual surgeons with CSF shunt surgery can be culled from the repository, as well as various demographic and clinical data. With suitable protections of privacy, confidentiality, and security, these data can be accessed for academic research and health administrative analysis.The authors from Vancouver, British Columbia, Canada and Salt Lake City, Utah, studied 3,794 first CSF shunt insertions in patients under 19 years of age performed by 181 surgeons for treatment of hydrocephalus over a 12-year period beginning in 1989. The outcomes studied were infection and reoperation for complications. Survival of the shunts without one or the other adverse outcome was analyzed with lifetable methodologies. Shunts inserted by surgeons with greater than the median experience had better survival than shunts inserted by surgeons with lesser experience. The 6-month risks of shunt failure were 31% and 38%, respectively, and although this gap diminished at later points in time, the difference between the 2 survival curves was highly significant (P=.001). The more experienced surgeons had an infection rate of 7%, while the less experienced surgeons had a rate of 9.4%, also a highly significant difference (P=.006). In a proportional hazards model, surgeon experience and surgeon infection rate retained significance as determinants of shunt survival, along with patient-specific factors such as age and etiology.Most surgeons endorse the general proposition that surgical experience makes a difference in patient outcomes, but they are likely to disagree about how much experience makes how much of a difference. One might gain some perspective by considering the design of 2 randomized, controlled, multicenter shunt insertion trials conducted (by these authors) in the 1990s.2,3 The trials were both powered at β = 0.8 to detect a clinically significant reduction in the risk of shunt failure at 1 year between the experimental and control arms. In both trials a “clinically significant” reduction was defined as 50%, typically from 0.4 to 0.2. From this perspective, the effect of surgeon experience on shunt survival in the current report may appear marginal.The American Academy of Pediatrics has gone on record as supporting referral of children with surgical conditions, including infantile hydrocephalus, to pediatric surgical subspecialists at regional pediatric centers.4 There are many practical justifications for this position but, until recently, substantiation of this position by actual outcomes data has not been possible. Clearly, a parent, a referring physician, or a health systems planner may wish to weigh surgeon experience in their respective deliberations, but other factors, particularly access to care, will have weight as well.It may be somewhat draining to think that without an experienced pediatric neurosurgeon, the risk of complications for a child requiring shunt placement is increased. Yet, more careful reading of this study will show that the findings are not as conclusive as the authors purport. For example, information regarding whether one specific neurosurgeon was the reason for the good or bad results versus many different neurosurgeons is not available in this data set. In addition, the involvement of trainees in these cases could not be determined. Thus, the limitations of this study will, hopefully, reduce the pressure on less experienced, yet fully boarded pediatric neurosurgeons who undertake this very common neurosurgical procedure.

Primary Excision of Pediatric Posterior Fossa Abscesses – Towards Zero Mortality?

Nine children with infratentorial brain abscesses were treated at our institution over a 3-year period. Seven of them were boys and two were girls. In five cases, the abscesses were otogenic, and in two cases, the cause was tubercular (including one case of tubercular otitis). There were three cases of abscess formation in dermoids. All cases were managed with primary excision of the abscess. The average hospital stay was 12 days, and there was no mortality. The most common complication was hydrocephalus, noticed in three patients, of whom one eventually required shunt placement. Our policy of primary excision of these abscesses has yielded gratifying results. This approach also resulted in minimal morbidity and a substantially shortened hospital stay. Moreover, primary excision yields definitive histopathology of the lesion, especially in cases of tubercular and dermoid etiologies.

Linear Accelerator Radiosurgery for Meningiomas in and around the Cavernous Sinus

OBJECTIVE A retrospective study to evaluate the efficacy and side effects of linear accelerator radiosurgery in the treatment of cavernous sinus meningiomas. METHODS Between 1993 and 2001, 42 patients with meningiomas involving the cavernous sinus underwent linear accelerator radiosurgery at our institution. A mean radiation dose of 14 Gy was delivered to the tumor margin. The median tumor volume was 8.2 cm3 (mean, 8.4 cm3). Median follow-up was 36 months (mean, 38 mo). RESULTS Control of tumor growth was achieved in 97.5% of the patients. There was no mortality or permanent extraocular motor or pituitary dysfunction. Treatment-related complications included new trigeminal neuropathy in 4.7% and a new visual field defect in 2.8%. Two patients required shunt placement after developing hydrocephalus. One patient with symptomatic temporal lobe edema underwent partial excision of the tumor. Improvement of existing cranial neuropathies was noted in 29% of affected trigeminal nerves, in 22% of oculomotor nerves, and in 13% of Cranial Nerves IV and VI. CONCLUSION This study indicates that linear accelerator radiosurgery can achieve a high control rate of meningiomas involving the cavernous sinus with no mortality and a low incidence of morbidity.

Linear Accelerator Radiosurgery for Meningiomas in and around the Cavernous Sinus

A retrospective study to evaluate the efficacy and side effects of linear accelerator radiosurgery in the treatment of cavernous sinus meningiomas. Between 1993 and 2001, 42 patients with meningiomas involving the cavernous sinus underwent linear accelerator radiosurgery at our institution. A mean radiation dose of 14 Gy was delivered to the tumor margin. The median tumor volume was 8.2 cm3 (mean, 8.4 cm3). Median follow-up was 36 months (mean, 38 mo). Control of tumor growth was achieved in 97.5% of the patients. There was no mortality or permanent extraocular motor or pituitary dysfunction. Treatment-related complications included new trigeminal neuropathy in 4.7% and a new visual field defect in 2.8%. Two patients required shunt placement after developing hydrocephalus. One patient with symptomatic temporal lobe edema underwent partial excision of the tumor. Improvement of existing cranial neuropathies was noted in 29% of affected trigeminal nerves, in 22% of oculomotor nerves, and in 13% of Cranial Nerves IV and VI. This study indicates that linear accelerator radiosurgery can achieve a high control rate of meningiomas involving the cavernous sinus with no mortality and a low incidence of morbidity.

Microsurgical Fenestration of the Lamina Terminalis Reduces the Incidence of Shunt-dependent Hydrocephalus after Aneurysmal Subarachnoid Hemorrhage

Hydrocephalus requiring shunt placement is a common complication after aneurysmal subarachnoid hemorrhage (aSAH). Previous investigations suggest that fenestration of the lamina terminalis during microsurgery for aSAH may be associated with a reduced rate of shunt-dependent hydrocephalus. We report a retrospective analysis correlating fenestration of the lamina terminalis with decreased shunt-dependent hydrocephalus after aSAH.During the past decade, 582 patients were admitted to our institution with aSAH. We compared the rate of shunting in patients operated on by a neurosurgeon ("index neurosurgeon") who routinely fenestrated the lamina terminalis (>98% of his patients) with that in patients managed by 14 other neurosurgeons who rarely fenestrated the lamina terminalis (<5% of their patients) and by 6 interventional neuroradiologists. The total cohort was subdivided into two groups on the basis of surgical approach and microsurgical access to the lamina terminalis. Group A included frontosphenotemporal craniotomies, an approach in which the lamina terminalis is accessible, and Group B included other approaches in which the lamina terminalis is not accessible. Shunting rates of the index neurosurgeon and those of the other practitioners were compared within Groups A and B. Shunting rates were compared by logistic regression and multivariable analysis. This study design isolates the effect of fenestrating the lamina terminalis on the incidence of shunt-dependent hydrocephalus.In Group A, the index neurosurgeon had a significantly lower rate of shunting, 2.3%, versus 12.6% for other practitioners (P = 0.011; odds ratio, 0.15). In Group B, in which the approach did not allow microsurgical fenestration of the lamina terminalis, there was no difference (P = 0.789) in the rate of shunting between the index neurosurgeon (10.0%) and other practitioners (13.2%).Fenestration of the lamina terminalis appears to be associated with a decreased incidence of shunt-dependent hydrocephalus of more than 80% after aSAH. This straightforward microsurgical maneuver should be performed whenever possible during aneurysm surgery.

Microsurgical Fenestration of the Lamina Terminalis Reduces the Incidence of Shunt-dependent Hydrocephalus after Aneurysmal Subarachnoid Hemorrhage

Hydrocephalus requiring shunt placement is a common complication after aneurysmal subarachnoid hemorrhage (aSAH). Previous investigations suggest that fenestration of the lamina terminalis during microsurgery for aSAH may be associated with a reduced rate of shunt-dependent hydrocephalus. We report a retrospective analysis correlating fenestration of the lamina terminalis with decreased shunt-dependent hydrocephalus after aSAH. During the past decade, 582 patients were admitted to our institution with aSAH. We compared the rate of shunting in patients operated on by a neurosurgeon ("index neurosurgeon") who routinely fenestrated the lamina terminalis (>98% of his patients) with that in patients managed by 14 other neurosurgeons who rarely fenestrated the lamina terminalis (<5% of their patients) and by 6 interventional neuroradiologists. The total cohort was subdivided into two groups on the basis of surgical approach and microsurgical access to the lamina terminalis. Group A included frontosphenotemporal craniotomies, an approach in which the lamina terminalis is accessible, and Group B included other approaches in which the lamina terminalis is not accessible. Shunting rates of the index neurosurgeon and those of the other practitioners were compared within Groups A and B. Shunting rates were compared by logistic regression and multivariable analysis. This study design isolates the effect of fenestrating the lamina terminalis on the incidence of shunt-dependent hydrocephalus. In Group A, the index neurosurgeon had a significantly lower rate of shunting, 2.3%, versus 12.6% for other practitioners (P = 0.011; odds ratio, 0.15). In Group B, in which the approach did not allow microsurgical fenestration of the lamina terminalis, there was no difference (P = 0.789) in the rate of shunting between the index neurosurgeon (10.0%) and other practitioners (13.2%). Fenestration of the lamina terminalis appears to be associated with a decreased incidence of shunt-dependent hydrocephalus of more than 80% after aSAH. This straightforward microsurgical maneuver should be performed whenever possible during aneurysm surgery.

Symptomatic supratentorial arachnoid cysts in children

This study was undertaken to evaluate the clinical and radiologic long-term outcome of symptomatic primary arachnoid cysts in pediatric patients. Thirty-three children, ranging from 2 months to 17 years of age (mean age, 6 years) were treated. Craniotomy and fenestration of the cyst were used for temporal fossa and midline cysts in 24 patients (73%); later, two patients required shunt placement. Shunting device implantation was performed for cerebral convexity cysts in nine patients (27%), and two patients required a subsequent craniotomy and fenestration of the cyst. Four patients (12%) required additional surgery because of clinical progression rather than for cyst enlargement. Eleven patients (33%) experienced a cyst reduction of more than 50% compared with the original size on imaging studies. There was a significant correlation with the alleviation of symptoms ( P < 0.005), regardless of the treatment used. Complete alleviation of symptoms was achieved in all patients after treatment, regardless of cyst reduction. Long-term follow-up of 70 ± 9.3 months demonstrated no recurrence of symptoms or progressive enlargement of the arachnoid cyst in all children.

Characteristics of Ventricular Shunt Malfunctions among Patients with Neurocysticercosis

Ventricular shunts used to relieve hydrocephalus among patients with neurocysticercosis have been plagued by high shunt malfunction rates. We examined the characteristics of shunt malfunctions among patients with neurocysticercosis. This is a retrospective chart review of data for 122 patients who were admitted with a diagnosis of cysticercosis during a 5.5-year period. Cases of hydrocephalus requiring shunt placement were reviewed with respect to the segment of shunt obstruction, disease activity at the time of shunt placement, and the effects of antihelminthic treatment on shunt failures and longevity. Twenty-one patients required 49 operations for relief of hydrocephalus, including 22 new shunt placements, 23 revisions, and 4 cyst extirpations. Of these shunt failures, 78% occurred within the first 12 months and 96% within 3 years. Of the failures that occurred in the distal segment, 75% occurred within 6 months. By comparison, 33% of proximal segment obstructions and 50% of the total number of valve obstructions occurred within the first 6 months. Of the shunts placed during the vesicular stage of infection, 63% required revisions, compared with 29% of those placed during the colloidal through calcified stages. Nineteen shunts were placed during the vesicular stage, and nine patients received a full course of antihelminthic treatment after shunt placement. In less than 6 months, 33% of the cases involving shunt placement followed by antihelminthic treatment exhibited shunt failure, compared with 90% of the cases without antihelminthic treatment (P < 0.05, chi(2) test). Among patients with vesicular stage cysticercosis, placement of a ventriculoperitoneal shunt followed by a course of antihelminthic medication seems to promote shunt longevity.

Can prenatal ultrasound findings predict ambulatory status in fetuses with open spina bifida?

Objective: To determine whether prenatal sonographic findings in fetuses with open spina bifida can predict ambulatory potential and the need for postnatal shunt placement. Study Design: Ongoing pregnancies complicated by isolated open spina bifida from January 1996 to March 2000 were studied retrospectively. Static images and reports generated every 3-4 weeks from diagnosis until delivery were reviewed for lesion level and type, ventricular width, and lower extremity appearance. Operative summaries as well as neonatal and pediatric charts were reviewed. Ambulatory was defined in infants ≥2 years old as walking with or without appliances. In those <2 years of age, ambulatory was defined as at least 4/5 lower extremity muscle strength. Results: Thirty-three cases of isolated open spina bifida were identified. Lower (more caudal) lesion levels and smaller ventricular size were associated with ambulatory status in univariate analyses (P <.001, P =.003, respectively). No infant with a thoracic lesion was ambulatory (n = 11); all had ventriculomegaly diagnosed prenatally and all required shunt placement. In contrast, all infants with L4-sacral lesions (n = 10) were ambulatory, and 60% had ventriculomegaly diagnosed prenatally. Of patients with L1-L3 lesions (n = 12), 50% were ambulatory. In this group, ambulatory potential could not be determined by the presence of ventriculomegaly, ventricular size, or the presence of club foot. In the entire cohort, no infant with a myeloschisis was ambulatory, and all infants except one with a sacral lesion required postnatal shunt placement. Conclusions: Sonographic determination of lesion level and type is useful in predicting the ambulatory potential of fetuses with open spina bifida. (Am J Obstet Gynecol 2001;185:·1016–20.)

Changes in echogenicity of spinal subarachnoid space associated with intracranial hemorrhage: new observations.

The role of subarachnoid blood and secondary, sterile inflammation in the pathogenesis of posthemorrhagic hydrocephalus (PHH) is not well understood. The aims of this study were to study the frequency and rate of spread of blood into the spinal subarachnoid space (SSS) and to evaluate the relationship of this finding and PHH. Nine premature babies with major intracerebral hemorrhage (ICH, grade 3 or higher), and ten premature infants with minor ICH (grade 1) or no evidence of ICH (control group) were identified and underwent serial cranial and spinal sonography at the time of initial diagnosis, 12-24 h after the ICH and weekly thereafter for at least 9 weeks. Sagittal and axial scans of the thoracolumbar spine were obtained and evaluated for the presence of echogenic debris in the dorsal SSS. Six additional patients who had cranial and spinal sonography died within the 1st week of life and underwent post-mortem examinations. The SSS was echo-free (normal) in all cases at the time of initial sonographic diagnosis of ICH. Within 24 h, all babies with major ICH had developed increased echogenicity of the cervical and thoracic SSS. Echogenicity of the SSS decreased gradually over several weeks. Although transient ventricular dilatation was present in every patient, only one patient had rapidly progressive PHH requiring shunt placement. Transient cysts of the cervicothoracic subarachnoid space were identified in two patients 6-7 weeks after ICH. The subarachnoid space remained echo-free in all control infants At autopsy, all four infants with echogenic spinal debris had blood or blood products in the spinal subarachnoid space, whereas two infants with echo-free spinal images did not. Spread of blood from the ventricular system into the spinal subarachnoid space after ICH is common and can be seen within 24 h of initial ICH. Subarachnoid blood is associated with post-hemorrhagic ventricular dilatation and transient spinal subarachnoid cyst formation.

Postoperative Hydrocephalus in Cranial Base Surgery

The incidence of postoperative hydrocephalus and factors relating to it were analyzed in 257 patients undergoing cranial base surgery for tumor resection. A total of 21 (8%) patients developed postoperative hydrocephalus, and all required shunting, Forty-two (17%) patients developed cerebrospinal fluid (CSF) leak that required placement of external drainage systems (ventriculostomy or lumbar drain, or both); 10 (23%) of these 42 patients eventually needed shunt placement to stop the leak because of hydrocephalus. Prior craniotomy, prior radiation therapy, and postoperative CSF infection were also associated with an increased risk of developing hydrocephalus (48% versus 6%, 19% versus 8%, and 14% versus 7%, respectively). Prior radiation and postoperative CSF infection increased the risk of CSF leak in patients with hydrocephalus (30% versus 18% and 30% versus 9%, respectively). CSF leak and hydrocephalus commonly occurred in patients who underwent resection of a glomus tumor. In conclusion, 8% of patients who underwent cranial base surgery for tumors developed de novo hydrocephalus; half of them also had CSF leak in addition to hydrocephalus; and all required shunt placement for CSF diversion.

Comparison of Near-Infrared Spectroscopy and Somatosensory Evoked Potentials for the Detection of Cerebral Ischemia During Carotid Endarterectomy

Background and Purpose—We sought to assess the clinical value of regional cerebral saturation (rSo2) obtained by means of the cerebral oximeter INVOS 3100A (Somanetics) in comparison to monitoring of somatosensory evoked potentials (SEP) for the reliable detection of severe cerebral ischemia requiring shunt placement in the individual patient undergoing carotid surgery under general anesthesia. Methods—In 317 patients undergoing reconstructive surgery on the internal carotid artery, simultaneous recordings of SEP and rSo2 were obtained throughout the operation. Results—All 287 patients with preserved cortical SEP remained neurologically intact. Shunt placement was performed in 27 patients (9%) after flattening of cortical SEP during cross-clamping of the internal carotid artery. A stable rSo2 value just before cross-clamping and the lowest value after cross-clamping were registered, and the decrease was calculated. A statistically significant (P<0.01) decrease of rSo2 after cross-clamping could be found i...

Intrinsic brainstem tumours in childhood: a report of 35 children followed for a minimum of 5 years

The presentation, pathology and outcome of 35 children with intrinsic brainstem tumours treated at our institution between 1980 and 1990 have been reviewed. Eight children remain alive. There were 19 girls and 16 boys. Mean age at diagnosis was 5 years. The mean duration of symptoms prior to diagnosis was 5 months. The diagnosis was made by computed tomography (CT) in all children and magnetic resonance imaging (MRI), in addition, for 24 children. Twenty-seven tumours (77%) were diffuse, three (8.6%) were predominantly cystic, three (8.6%) were exophytic and two (5.7%) were focal. Cervicomedullary tumours were not included in this study. Definitive histology was obtained in 13 children (37.1%), eight (22.9%) by biopsy alone and five (14.3%) after surgery to debulk the tumours. Eleven of these cases were astrocytomas and two were primitive neuroectodermal tumours (PNET). Twelve children (34.3%) required shunt placement for hydrocephalus. Twenty-eight children (80%) were irradiated using conventionally fractionated radiotherapy to a total dose between 50 and 55 Gy. Six children (17.1%) also received chemotherapy. The overall mean survival time was 10 months, but five of six children who had their tumours debulked survived free of progressive disease for more than 5 years following their diagnosis. The prognosis for brainstem tumours in children remains poor with only a minority falling into the surgically resectable (good prognosis) group.

Intraoperative Use of Somatosensory Evoked Potentials for Brain Monitoring During Carotid Surgery

Somatosensory evoked potentials (SSEP) are a valuable clinical tool in the operating theater. Multichannel SSEP monitoring is an objective measure of CBF and cerebral function. The monitoring of the SSEP during carotid surgery is a simple and reliable method of determining the effect of carotid clamping on CBF and the need for shunting. The diagnosis sensitivity and specificity of intraoperative SSEP monitoring for assessing the neurologic outcome of patients are over 95%. At least 16.1% of cases required shunt placement using SSEP monitoring.

Brainstem tumors in patients with neurofibromatosis type 1: a distinct clinical entity.

The natural history and the clinical and neuroimaging features of brainstem tumors in neurofibromatosis type 1 (NF1) are poorly understood. Magnetic resonance imaging (MRI) has been useful in NF1 in detecting intracranial abnormalities, especially of the brainstem. Brainstem tumors in NF1 have been confused clinically with non-NF1 brainstem tumors and radiographically with the increased T2 signal abnormalities, also known as "unidentified bright objects" (UBOs), which are common in NF1 and often located in the brainstem. This study, which evaluated 17 NF1 patients with brainstem tumors, is the largest series to date. Fifteen of 17 patients (88%) had neurologic signs and symptoms referable to brainstem dysfunction, including dysarthria, cranial neuropathies, and gross motor incoordination. Tumors were located primarily in the medulla in 14 of 17 NF1 patients (82%), in contrast to the pontine tumor location in the non-NF1 population. Seven NF1 patients (41%) required shunt placement for hydrocephalus at initial diagnosis, more frequent than in non-NF1 brainstem tumor patients. Six of 17 patients (35%) had evidence of radiographic tumor progression, but only three of them (18%) had correlative clinical progression. Two patients with progressive symptoms had partial surgical resection, and pathology revealed either fibrillary or anaplastic astrocytomas. Three patients were treated with radiation therapy, chemotherapy, or both, with two deaths. With a median follow-up of 52 months, 15 of 17 patients remain alive; 14 of them did not require adjuvant therapy. In our series, we describe NF1 brainstem tumors as a distinct clinical entity, much less aggressive than non-NF1 pontine tumors but more symptomatic than brainstem UBOs in NF1.

721-6 Pulmonary Balloon Valvuloplasty: Effective Palliation for Infants with Tetralogy of Fallot and Small Pulmonary Arteries

Infants with tetralogy of Fallot (TOF) and small pulmonary arteries (PAs) may need palliation to improve pulmonary blood flow and allow growth of the PAs prior to complete repair. Shunts may become occluded, distort the PAs or cause pulmonary overcirculation. As an alternative palliation, we performed pulmonary balloon valvuloplasty (PBV) on infants with TOF and small PAs. 20 infants, ages 1.8 ± 1.5 mo and weights 4.1 ± 1.6 kg, undervvent PBV as initial palliation for persistent cyanosis or “spells”. 4/20 pts were intubated prior to or for PBV All pts had pre and post-PBV angiograms. In all pts, single balloon valvuloplasty was performed. The ratio of balloon: pulmonary valve annulus (PVA) diameter was 1.51 ± 0.32. Post-PBV, there was no change in the PYA diameter (5.2 ± 1.1 mm vs 5.6 + 1.1 mm; p = 0.1) or PA branch diameter(4.1 ± 1.6 mm vs 4.5 ± 1.7 mm, p &gt; 0.05). The systemic 02 saturation increased from 81 ± 8% to 93 ± 6%. (p &lt; 0.001) 7/20 pts undervvent follow-up (F/U) cath 8.2 ± 2.4 mo post-PBV Compared to pre-PBV measurements, the PYA diameter increased from 5.2 ± 1.1 mm to 7.1 ± 1.4 mm (p &lt; 0.03) and the McGoon ratio increased from 1.4 ± 0.4 to 2.1 ± 0.3 (p &lt; 0.02). Of the 20 pts, 11 pts undervvent corrective surgery 8.0 ± 3.1 mo post-PBV with no surgical deaths; 5 pts remain in stable condition awaiting surgery; 3 pts required shunt placement 9-66 days post-PBV; 1 pt died due to other congenital anomalies. Pulmonary balloon valvuloplasty promotes growth of the PAs and PYA in infants with TOF and small PAs, offering a safe and effective alternative palliation for infants who are not yet candidates for complete repair.

Pediatric midbrain tumors: a benign subgroup of brainstem gliomas.

The presentation, radiographic findings and course of 17 children with MRI-documented intrinsic midbrain lesions are reviewed. The anatomic centers of all the lesions were tectal, peritectal, or tegmental. Lesions centered at the pineal gland were excluded. Signs of increased intracranial pressure from hydrocephalus requiring shunt placement were present in 14 patients. Histopathological diagnosis was confirmed in three tumors; these were low grade astrocytomas and all received focal irradiation, as did one unbiopsied tumor. The remaining 13 patients with no histopathological diagnosis received no therapy other than shunt placement in 11. All but one of the lesions have remained clinically and radiographically stable, with a 4-year progression-free and total survival of 94 and 100%, respectively. We conclude that mass lesions originating in the upper midbrain are a subset of intrinsic brainstem tumors with a relatively benign course, usually presenting with hydrocephalus after infancy. They may remain stable for considerable periods and may require no further therapy after treatment of hydrocephalus. Surgical biopsy and/or resection can usually be reserved for progressive or atypical lesions which may also require further adjuvant therapy.

Treatment of intraventricular hemorrhage in the premature infant with urokinase. A preliminary report.

Hydrocephalus secondary to intraventricular hemorrhage in the premature infant is common and is secondary to the presence of blood in the subarachnoid space. Rapid clearance of the blood may reduce the incidence of permanent hydrocephalus and mitigate the need for shunt placement. We have treated 4 premature infants with posthemorrhagic hydrocephalus with urokinase, a thrombolytic agent, instilled into the ventricles via a surgically paced ventricular access device. The infants were treated with 10,000 IU of urokinase twice a day for 1 week. No adverse reactions have occurred and none of the infants has required shunt placement. In a group of historical controls, the shunt rate was 87%.

The surgical and natural morbidity of aggressive resection for posterior fossa tumors in childhood.

The morbidity associated with gross total removal of pediatric posterior fossa tumors is well recognized although it is rarely isolated from other factors that comprise the management morbidity for these tumors. This study reviews (1) the operative and postoperative complications in 105 patients and (2) the neurological morbidity in a subset of 91 patients undergoing gross total removal of their tumor between 1982 and 1992. Gross total removal was achieved in 102 patients with a single procedure. Two patients with residual tumor underwent early repeat craniotomy for excision and 1 is being followed without repeat resection. Intra- and postoperative complications occurred in 33 patients and included hematoma requiring craniotomy (3), gastrointestinal hemorrhage (2), hydrocephalus requiring shunt placement (9), wound problems (4), and pseudomeningocele formation requiring additional treatment (5). Delayed onset hydrocephalus requiring shunting occurred in 2 patients and spinal deformity in 4 patients. Worsening of preoperative deficit (new cranial nerve palsies, worsening ataxia, bulbar dysfunction including apnea, mutism and seizures) occurred in 41% of patients operated on for primitive neuroectodermal tumors (PNET) (14/34), 53% of ependymomas (10/19), and 30% of astrocytomas (15/50). No patient who had a choroid plexus tumor was worsened by the procedure. Complete recovery of new postoperative deficits occurred in 14% of PNET (2/14), 50% of ependymoma (5/10) and 47% of astrocytoma (7/15), most often within 6 months of the procedure. Residual neurological morbidity, due to persistence of preoperative symptoms or due to deficits that occurred as the result of the surgical procedure, was assessed in a subgroup of 91 patients followed for an average of 48 months (2-147 months). This assessment did not include morbidity due to adjuvant therapy. Sixty-two percent of patients continued to exhibit abnormal cerebellar or bulbar signs. Forty-three percent of the total population exhibited limitation in function due to residual deficit. Only 38% of patients were both functionally normal and had a normal neurological examination at last follow-up.