Correlation between fractional anisotropy and motor outcomes in one-year-old infants with periventricular brain injury

PURPOSE

To determine whether motor outcomes of an exercise intervention beginning at 2 months corrected age (CA) in children with periventricular brain injury (PBI) are correlated with fractional anisotropy (FA) measures derived from diffusion tensor imaging (DTI) at 12 months CA.

MATERIALS AND METHODS

DTI was performed in eight infants with PBI who were randomly assigned to kicking and treadmill stepping exercise or a no-training condition. Development was assessed using the Alberta Infant Motor Scale (AIMS) and the Gross Motor Function Classification System (GMFCS). FA values were derived from regions of interest (ROIs) in the middle third of the posterior limb of the internal capsule (PLIC) and the posterior thalamic radiation (PTR).

RESULTS

Significant correlations were observed between motor development and FA measures. For PLIC, the correlation coefficients were 0.82 between FA and AIMS, and -0.92 between FA and GMFCS, while for PTR the corresponding correlation coefficients were 0.73 and -0.80, respectively.

CONCLUSION

Results of this study suggest that quantitative evaluation of white matter tracts using DTI at 12 months CA may be useful for assessment of brain plasticity in children.

Chorioamnionitis and brain damage in the preterm newborn

AIM

To evaluate the association between histological chorioamnionitis and brain damage (intraventricular hemorrhage and cystic periventricular leukomalacia) in the preterm newborn.

METHODS

This was a retrospective study on neonates born at less than 34 weeks gestational age, and their respective mothers, at three tertiary medical centers in the north of Portugal, from January 2001 to December 2002.

RESULTS

The study included 452 newborns (235 male/217 female; birth weight 1440 (515-2620) grams; gestational age 31 (23-33) weeks), 125 from mothers whose placenta showed signs of chorioamnionitis and 327 from mothers without the condition. The association between histological chorioamnionitis and: (1) intraventricular hemorrhage grades I-IV was OR 1.43 (95% CI 0.49-3.94); (2) intraventricular hemorrhage grades III and IV was OR 2.49 (95% CI 1.20-5.11); (3) cystic periventricular leukomalacia was OR 3.02 (95% CI 1.50-6.07). The association, adjusted for birth weight and gestational age, between chorioamnionitis and: (1) intraventricular hemorrhage grades III and IV was OR 0.94 (95% CI 0.39-2.28); (2) cystic periventricular leukomalacia was OR 1.94 (95% CI 1.03-4.61). The association between histological chorioamnionitis with funisitis and/or vasculitis and: (1) intraventricular hemorrhage grades I to IV was OR 1.27 (95% CI 0.52-3.10); (2) cystic periventricular leukomalacia was OR 2.08 (95% CI 0.72-5.98).

CONCLUSION

This study confirms the association between histological chorioamnionitis and cystic periventricular leukomalacia, but was unable to confirm the association between histological chorioamnionitis and intraventricular hemorrhage.

Cognitive visual impairment with good visual acuity in children with posterior periventricular white matter injury: a series of 7 cases

BACKGROUND

We describe a series of term and preterm children with occipito-parietal periventricular white matter abnormalities on magnetic resonance imaging (MRI) who manifest common clinical features of cognitive visual dysfunction. We also describe a strategy for taking clinical history that highlights the symptom complex and assists with management.

PATIENTS AND METHODS

A retrospective observational case series study of seven children with cognitive visual difficulties despite good (20/32 or better) visual acuities and MRI findings of periventricular white matter pathology in the territory subserving visual function. Structured history taking was used to identify and characterize the visual difficulties. Objective clinical findings (visual acuity, color vision, stereoacuity, visual fields, ocular motility, refraction, and fundoscopy) were recorded.

RESULTS

Seven children with visual acuities of 20/32 (0.200 logMAR) or better had symptoms of cognitive visual difficulties consistent with dorsal stream dysfunction. Four had strabismus of different types and were identified on the basis of parental concern expressed at the ocular motility clinic. The other three children presented to the general ophthalmology clinic. All seven children had various degrees of focal periventricular white matter pathology in a similar distribution on neuroimaging.

CONCLUSIONS

Children born prematurely are susceptible to periventricular white matter pathology. Such pathology can also occur in children born at term. This case series demonstrates that cognitive visual impairment due to periventricular white matter injury can occur despite good central visual function. A range of strategies to help affected children is described.

Ventricular Injury following Cranial Gunshot Wounds: Clinical Study

Gunshot wounds to the head are usually fatal injuries, despite all medical and surgical interventions. Ventricular injury is a poor prognostic factor-for penetrating cranial gunshot wounds. Intraventricular hemorrhage and ventricular lacerations are the main components of such injuries. The incidence, management, and outcomes of cases of ventricular injury secondary to cranial gunshot wounds that were treated during a 9-year period at Gülhane Military Medical Academy were examined. The study group consisted of 67 consecutive patients who were admitted to the Department of Neurosurgery with the diagnosis of ventricular injury, with different penetration sites. The patients had been injured by either bullets or shrapnel. Surgical treatment was performed for all patients with ventricular injuries and 22 (32.8%) died. Ventricular injury in cranial gunshot wounds is a complex severe type of trauma that requires serious treatment. Early radiological diagnosis and accurate treatment frequently had lifesaving roles for these patients.

Periventricular brain injury, visual motion processing, and reading and spelling abilities in children who were extremely low birthweight

Among children born at extremely low birthweight (ELBW: < 1000 g at birth) there is an association between the presence of periventricular brain injury (PVBI) and lowered performance on tests of reading and spelling ability. The present study was designed to determine if this association might be related to underlying dysfunction in the subcortical magnocellular visual pathway or its cortical targets in the dorsal stream, a prediction motivated by the magnocellular theory of dyslexia. Thirty-five ELBW children were divided into two groups based upon the presence or absence of PVBI (no PVBI, n = 11; PVBI, n = 24). The performance of these two groups was compared to that of a group of healthy full term children (n = 12) on a motion-defined form recognition task believed to tap into the functioning of the magnocellular pathway and/or the dorsal stream. ELBW children did, in fact, show a striking impairment on this task, with 71% of the sample performing at a level more than three standard deviations below the mean of full term controls. Surprisingly, their difficulties were not found to be related to either the presence of brain injury (verified by neonatal cranial ultrasound) or to problems with reading or spelling. An association was documented, however, between difficulties with motion processing and performance on several subtests of the Performance IQ scale of the Wechsler Intelligence Scale for Children-Third Edition. This latter finding is consistent with our earlier suggestion that magnocellular pathway/dorsal stream dysfunction may underlie problems with visuospatial and visuomotor performance in this population.

MRI demonstration of unsuspected intraventricular rupture of pyogenic cerebral abscesses in patients being treated for meningitis

We report three patients with pyogenic meningitis who showed a partial response to medical treatment. MRI demonstrated an unsuspected brain abscess with intraventricular rupture, a possible cause of the partial response to treatment.

Auditory temporal processing deficits in children with periventricular brain injury

The present study investigated whether auditory temporal processing deficits are related to the presence and/or the severity of periventricular brain injury and the reading difficulties experienced by extremely low birthweight (ELBW: birthweight <1000 g) children. Results indicate that ELBW children with mild or severe brain lesions obtained significantly lower scores on a test requiring auditory temporal order judgments than ELBW children without periventricular brain injury or children who were full-term. Structural equation modeling indicated that a model in which auditory temporal processing deficits predicted speech sound discrimination and phonological processing ability provided a better fit for the data than did a second model, which hypothesized that auditory temporal processing deficits are associated with poor reading abilities through a working memory deficit. These findings suggest that an impairment in auditory temporal processing may contribute to the reading difficulties experienced by ELBW children.

Periventricular cystic lesions in a preterm infant after a car accident during pregnancy

We report on a preterm infant born at 30+5/7 gestational weeks who developed severe cystic cerebral lesions after exposure to a car accident one day before delivery. The literature on car accidents during pregnancy is reviewed with specific focus on neonatal neurological outcome.

Early neonatal brain injury in histologic chorioamnionitis

The relation between clinical or histologic chorioamnionitis and early neonatal adverse neurologic outcome was investigated (n = 483). Histologic, but not clinical, evidence of chorioamnionitis was found to be a significant predictor of periventricular echodensity (odds ratio, 2.4; 95% CI, 1.8-3.2), echolucency (3.3; 1.9-5.6), ventriculomegaly (2.7; 1.8-4.2), intraventricular hemorrhage > or =3 (3.5; 2.4-5.2), and seizures (2.3; 1.4-3.7).

Subdural and intraventricular traumatic tension pneumocephalus: case report

Simple pneumocephalus most frequently arises as a complication of a head injury in which a compound basal skull fracture with tearing of the meninges allows entry of air into the cranial cavity. It can also follow a neurosurgical operation. Tension traumatic pneumocephalus with intraventricular extension is an extremely rare, potentially lethal condition that requires prompt diagnosis and treatment. We report the case of subdural and intraventricular accidental tension pneumocephalus occurring in a 26-year-old man as a result of skull fracture. This case is combined with rhinorrhea and meningitis that suggest some difficulties to treat. The operative procedure associated with medical treatment was performed and a good result was obtained.

Impaired osmoregulatory responses in rats with area postrema lesions

Area postrema lesions (APX) in adult male rats produced a robust spontaneous intake of 0.5 M NaCl, as reported previously. The largest NaCl intakes (up to 108 ml/day) were observed when there was little incidental damage in the medial subnucleus of the nucleus of the solitary tract adjacent to the caudal and middle portions of the area postrema. Rats with discrete APX also drank substantial amounts of 0.5 M NaCl when access to saline was restricted to 7 h/day (up to 30 ml in 1 h, 48 ml in 7 h). Such large NaCl intakes stimulated considerable water ingestion and renal sodium excretion, but together these responses usually were insufficient for osmoregulation during the 7-h test period. After systemic administration of hypertonic NaCl solution, rats with APX excreted less Na(+) in urine and secreted less vasopressin and oxytocin than control rats did. The prominent salt appetite, insufficient thirst and natriuresis in response to an ingested NaCl load, and blunted natriuresis and neurohypophysial hormone secretion in response to an injected NaCl load, all indicate that osmoregulatory responses are impaired in rats after APX.

ANG II and baroreflex function in rabbits with CHF and lesions of the area postrema

Blockade of the angiotensin II (ANG II) type 1 receptor (AT(1)) has been shown to restore baroreflex sensitivity in rats and rabbits with experimental chronic heart failure (CHF). Because the modulation of baroreflex function in response to ANG II is mediated in part by AT(1) receptors located in the area postrema, we hypothesized that lesions of the area postrema would prevent the enhancement in baroreflex function in response to AT(1)-receptor blockade in rabbits with pacing-induced CHF. Experiments were carried out on 24 male New Zealand White rabbits that were divided into sham (n = 12) and lesioned (n = 12) groups further divided into normal and CHF subgroups (n = 6 each). All rabbits were identically instrumented to measure cardiac external dimensions, central venous pressure, arterial pressure, heart rate (HR), and renal sympathetic nerve activity (RSNA). After 3-4 wk of pacing, baroreflex sensitivity (infusions of phenylephrine and nitroprusside) was evaluated before and after intravenous administration of the AT(1)-receptor antagonist L-158,809. Maximum baroreflex sensitivity in nonpaced rabbits was 5.4 +/- 0.7 beats. min(-1). mmHg(-1) and 5.2 +/- 0.5% of maximum/mmHg for HR and RSNA curves, respectively, and was not altered by L-158,809 in either intact or lesioned rabbits. In contrast, L-158,809 enhanced baroreflex sensitivity in intact rabbits with CHF (HR from 1.6 +/- 0.3 to 4.1 +/- 0.7 beats. min(-1). mmHg(-1), P < 0.001; RSNA from 2.3 +/- 0.2 to 4.9 +/- 0.4% of maximum/mmHg, P < 0.001). However, in CHF rabbits with area postrema lesions, L-158,809 failed to enhance baroreflex sensitivity. Interestingly, area postrema lesions did not normalize the baroreflex in CHF rabbits. From these data we conclude that the area postrema mediates the normalization of baroreflex sensitivity after AT(1) blockade in rabbits with CHF but does not modify resting baroreflex function.

Scanning electron microscopy of the floor of the fourth ventricle in rats subjected to graded impact injury to the sensorimotor cortex

OBJECT

Respiratory dysfunction including apnea frequently follows head injury in humans. The purpose of this study was to identify any structural alterations in the region of brainstem respiratory nuclei that might account for immediate postinjury respiratory abnormalities in anesthetized experimental animals.

METHODS

Using scanning electron microscopy, the authors examined the floor of the fourth ventricle in injured rats after a piston strike to the sensorimotor cortex that depressed the dura 1, 2, or 4 mm. The rats were killed within minutes of injury. Cortical impact depths measuring either 1 or 2 mm (eight rats) produced no respiratory abnormalities, and the structural integrity of the ependymal lining of the ventricular floor in these animals was not compromised. Thirteen rats were subjected to impact to a 4-mm depth and 10 of these exhibited immediate temporary or permanent apnea. The medullae of nine of these rats were studied using scanning electron microscopy, and the fourth ventricular floors of all nine rats showed tears. Four rats that exhibited immediate, permanent apnea had tears in the caudal fourth ventricle floor near the obex, whereas five rats with no or only transient apnea had tears located more anteriorly, near the aqueduct or laterally. Changes in cerebrospinal fluid flow or pressure dynamics may have caused these tears. Light microscopy, focused near the area postrema, revealed a shearing defect through the ependyma of the fourth ventricular floor into the subjacent neuropil with a disruption of axonal pathways.

CONCLUSIONS

Respiratory neuronal network components lying within 2 mm of the area postrema may well have been disrupted by the caudal tears producing permanent apnea. A similar phenomenon could account for the transient or permanent postinjury apnea seen in humans with severe head injury.

Traumatic intraventricular hemorrhage treated with intraventricular recombinant-tissue plasminogen activator: technical case report

OBJECTIVE AND IMPORTANCE

Traumatic intraventricular hemorrhage (IVH) can result in association with acute obstructive hydrocephalus, repetitive malfunction of external ventricular drains (EVDs), and uncontrollable increased intracranial pressure. We report a case showing the safe and effective use of intraventricular recombinant-tissue plasminogen activator in a child with severe brain injury and acute hydrocephalus from IVH.

CLINICAL PRESENTATION

A 15-year-old male patient presented to us after a motor vehicle accident with bilateral extensor posturing, intracerebral and IVH, and acute obstructive hydrocephalus.

INTERVENTION

A right EVD was placed and functioned only transiently. A left EVD was placed and functioned only transiently. Because of the inability to maintain ventricular drainage, rising intracranial pressure, and worsening clinical status, 5 mg of recombinant-tissue plasminogen activator was injected through each EVD. Excellent EVD function was obtained quickly, with control of intracranial pressure and improvement in clinical status and without hemorrhagic complication.

CONCLUSION

With obstructive hydrocephalus secondary to acute traumatic IVH that cannot be controlled with EVD because of recurrent obstruction from intraventricular blood, intraventricular recombinant-tissue plasminogen activator can be effective and safe, despite preexisting multiple hemorrhagic intracranial injuries.

[Endoscopic projectile extraction in treatment of a gunshot injury to the head]

HISTORY AND CLINICAL FINDINGS

A 14-year-old boy had in war-torn Bosnia sustained a transcranial gunshot wound from a 7.65 mm bullet. After primary medical care with craniotomy and the removal of bony fragments and cerebral debris followed by a duraplasty, he was transported to the French-German Field Hospital. On arrival he was breathing spontaneously and in stable cardiovascular state but with impaired responsiveness and somnolent. His pupils were moderately dilated with slight anisocoria (right > left). His gaze was deviated to the left and he had vertical gaze paralysis as well as right central facial nerve paresis. In addition he had a mild diencephalic syndrome, right hemiplegia and a right hemihypaesthesia with increased muscle tone, especially of the leg, paratonia and right positive Babinski reflex. There also was a marked ciliospinal reflex and he had a bulbar speech as well as cognitive and memory abnormalities.

INVESTIGATIONS

Haemoglobin and haematocrit were below normal (12.1 g/dl and 35.0%, respectively), while biochemical tests were normal. Cranial computed tomography localized the bullet in the pineal recess of the 3rd ventricle and the lamina quadrigemina.

DIAGNOSIS, TREATMENT AND COURSE

These findings indicated endoscopic transcranial removal of the bullet, achieved with a rigid endoscope and forceps along the entry track. Subsequent intensive care proceeded without complication. On discharge the boy was normal oriented and ready to make contact. The neurological defects were regressing.

CONCLUSION

Endoscopic transcranial removal of a bullet wedged in the brain is a relatively sparing neurological procedure which, under unusual circumstances and conditions, can achieve a satisfactory result even with limited facilities.

Relation between diffuse axonal injury and internal head structures on blunt impact

Diffuse axonal injury (DAI) is a severe head injury, which exhibits symptoms of consciousness disturbance and is thought to occur through rotational angular acceleration. This paper analyzes the occurrence of DAI when direct impacts with translational accelerations are applied to two-dimensional head models. We constructed a human model reproducing the human head structure, as well as modified human models with some internal head structures removed. Blunt direct impacts were applied from a lateral direction to the bottom of the third ventricle, considered to be the center of impact, using an impactor. The analysis was done by comparing the macroscopic manifestation of DAI with the shear stress as the engineering index. In the analytical data obtained from the human model, shear stresses were concentrated on the corpus callosum and the brain stem, in the deep area. This agrees with regions of the DAI indicated by small hemorrhages in the corpus callosum and the brain stem. The analytical data obtained by the modified human models show that the high shear stress on the corpus callosum is influenced by the falx cerebri, while the high shear stress on the brain stem is influenced by the tentorium cerebelli and the shape of the brain. These results indicate that DAI, generally considered to be influenced by angular acceleration, may also occur through direct impact with translational acceleration. We deduced that the injury mechanism of DAI is related to the concentration of shear stress on the core of the brain, since the internal head structures influence the impact stress concentration.

Three dimensional image reconstruction of neuroanatomical structures: methods for isolation of the cortex, ventricular system, hippocampus, and fornix

Magnetic Resonance (MR) imaging allows volumetric quantification of a variety of neuroanatomical structures using two dimensional (2D) images as well as three-dimensional (3D) reconstruction of the brain and any of its constituent parts. Three-dimensional analysis permits integration of the neuroanatomical changes which occur in pathologic states, with the cognitive and behavioral changes elucidated through neuropsychological assessment. This paper describes uniform methods for 3D neuroanatomical isolation of the neocortex, ventricular system, and hippocampus in both normal and pathologic states. The 3D methods are described in detail using two different software programs, ANALYZE and IMAGE. Three-dimensional neuroanatomical reconstructions were carried out on a patient who sustained a very severe traumatic brain injury. The 3D image analysis in the patient with traumatic brain injury, revealed structural changes in frontal and temporal cortex, ventricular dilation, and hippocampal atropy. The neuropsychological impairments in this patient, were consistent with the observed neuroanatomical changes revealed on 3D image reconstruction. This technology permits precise determinations of the extent and severity of the neuroanatomical changes which follow neurological injury disease.

Porencephaly secondary to fetal trauma during amniocentesis

BACKGROUND

There has been one reported case of porencephaly diagnosed postnatally as a result of amniocentesis. We report the first antenatal diagnosis of porencephaly, which apparently resulted from penetration of the fetal skull during amniocentesis.

CASE

A 37-year-old woman had genetic amniocentesis at 16 weeks' gestation. The fetal skull was penetrated during the unguided procedure. Porencephaly discovered at 28 weeks' gestation was confirmed by imaging studies in the neonatal period.

CONCLUSION

Inadvertent fetal skull penetration appeared to result from amniocentesis unguided by continuous ultrasound.

Complications of fourth-ventricular shunts

Fourth-ventricular shunting is commonly used to treat symptomatic posterior fossa cysts of the Dandy-Walker malformation and trapped fourth ventricle. Although the benefits of this procedure have been widely reported, there is a paucity of data on the pitfalls of posterior fossa shunting in the neurosurgical literature. During the 4-year period from July 1989 to June 1993, we placed fourth-ventricular shunts in 12 patients. Remarkably, 5 patients suffered complications related to posterior fossa catheter placement (42% rate). Three of these patients developed new cranial nerve dysfunction caused by direct injury to the floor of the fourth ventricle, 1 patient suffered an intracystic hemorrhage and acute shunt malfunction, and 1 patient had the catheter tip in the brainstem on postoperative studies without new neurological deficit. We conclude that placement of fourth-ventricular shunts can be fraught with complications which we believe is related to technique. We propose that altering the trajectory of the ventricular catheter from our usual midline technique to a more lateral position will lessen the chances for injury to the floor of the fourth ventricle. In this manner we hope to decrease our incidence of complications for this procedure.

Effects of subcortical lesion site on human emotional behavior

This is the first quantitative group study of recognition, expression, and other social-emotional behaviors after third ventricle damage in humans. Hypothalamic damage often induced appetitive disorders without affecting other emotional functions. In contrast, lesions in several hemispheric sites, especially right medial temporal, impaired emotional recognition; frontal and basal ganglia damage impoverished facial emotional expressions, this deficit being dissociated from general facial-motor impairment. These functional dissociations indicate that social-emotional behavior is regulated by multiple neural circuits, many of which by-pass hypothalamic nuclei. This conclusion is shown to be consistent with (a) the considerable animal evidence linking appetitive-survival behaviors with hypothalamic activity and (b) the accumulating human data on the specific contributions of hemispheric cortical-subcortical systems in the regulation of emotional recognition and expression.

Stereotactic localization and removal of a bullet in the third ventricle causing obstructive hydrocephalus after a cerebral gunshot wound: case report

A bullet, lodged in the pineal-posterior region of the third ventricle and causing obstructive hydrocephalus, was removed without damage to critical adjacent vascular structures using stereotactic localization followed by laser-guided stereotactic craniotomy. Stereotactic techniques provided precise target localization and allowed dissection to be restricted to the previously injured missile track, thus avoiding any additional morbidity from the surgical procedure.

Intraventricular hemorrhage in blunt head trauma: an analysis of 43 cases

Before the advent of computed tomography, intraventricular hemorrhage (IVH) from any source was thought rare and invariably fatal. Although intraventricular blood is readily identifiable with computed tomography, there has been little systematic study of its significance in blunt head trauma. Forty-three patients with traumatic IVH were prospectively identified in 1 year at Harborview Medical Center (University of Washington). Most were victims of motor vehicle accidents and suffered severe head injuries. IVH occurred alone in two patients; superficial contusions and subarachnoid hemorrhage were the most common associated finding. Blood was present in only one or both lateral ventricles in 25 patients; only the 3rd or 4th ventricles in 4 and all ventricles in 14 instances. There were 3 intracerebral hematomas and 14 basal ganglion hemorrhages. All of the former and half of the latter communicated with the adjacent lateral ventricle. Extra-axial hematomas appeared more common when only the lateral ventricles were involved, whereas corpus callosum or brain-stem hemorrhage appeared more likely when all the ventricles were involved. Acute hydrocephalus was rare, and ventricular drainage was needed in only four cases. Intracranial pressure (ICP) was elevated (> 15 mm Hg) in 46% of patients. The amount of IVH was related inversely with the Glasgow Coma Scale, but not with increased ICP. The presence of IVH indicated a poor outcome, with only half of the patients being independent at a 6-month follow-up. Poor outcome was associated with increasing age, low admission Glasgow Coma Scale, the presence of space occupying lesions if only the lateral ventricles were involved, and hemorrhage in all four ventricles.(ABSTRACT TRUNCATED AT 250 WORDS)

Visual memory deficits after damage to the anterior commissure and right fornix

A 47-year-old right-handed woman suffered an accidental dural perforation in the course of intranasal drainage of a right-sided sphenoid mucocele. Radiological examination revealed a small hematoma involving the anterior commissure, the right foramen of Monro, and the right fornix, resulting in severe anterograde amnesia for visual stimuli. Visual retention disturbances were manifested by a loss of the ability to conjure up new visual images, loss of topographical memory, and the cessation of dreaming. Dissociation was striking between severe deficits on tests exploring anterograde visual memory, revisualization, visuospatial organization, construction abilities, and normal or mildly impaired performance on tests implying verbal material and verbal memory. In agreement with experimental findings, it is postulated that combined damage to the anterior commissure and fornix on the right side could cause severe deficits in visual retention in humans.

Traumatic lesions of the suprasellar region: MR imaging

The authors studied nine patients with injuries to the suprasellar region with 1.5-T magnetic resonance (MR) imaging. Five patients had chiasmal injuries diagnosed by means of clinical examination. MR imaging demonstrated complete transection in two of these five patients, contusion of the chiasm by inferior herniation of the gyrus rectus in one, and a normal chiasm in two. Two patients had large tears of the floor of the third ventricle resulting in wide communication between the third ventricle and the prepontine cistern. One of these patients also had an avulsed third nerve. Transection of the pituitary stalk was seen in two patients. MR imaging can demonstrate injuries to the suprasellar structures. The MR imaging appearance of optic chiasm correlates with different types of injury to the chiasm described in the clinical literature and may alleviate the need for additional diagnostic studies to help explain the patient's symptoms.

Inhibition of the cortisol response to systemic angiotensin II by forebrain lesions involving the anterior wall of the third ventricle

The influence of bilaterally narrow, medial forebrain lesions on the increase in plasma cortisol concentration normally seen in response to intravenous angiotensin II was studied in five goats. For comparison, the pre- and post-lesion cortisol responses to intravenous endotoxin were also evaluated. The cortisol response to angiotensin was extinguished in two goats, whereas a slightly attenuated response to endotoxin was still obtained post-lesioning. In these animals the lesions embraced the subfornical organ (SFO), the organum vasculosum of the lamina terminals (OVLT) and the interjacent anterior wall of the third ventricle. In two other goats, in which the SFO was completely destroyed but the OVLT remained largely intact, the lesions caused about 50% reduction of the cortisol response to angiotensin without any concomitant reduction of the response to endotoxin. It is concluded that ACTH-cortisol release in response to systemic angiotensin II is not mediated exclusively by receptors for the octapeptide confined to the SFO. Angiotensin receptors in the OVLT seem to be equally important in this respect.

Lesions of the anteroventral third ventricle prevent salt-induced hypertension in the borderline hypertensive rat

Many forms of experimental hypertension depend on the integrity of the periventricular tissue surrounding the anteroventral third ventricle. The current investigation examined the extent to which this forebrain area is necessary for the elaboration of salt-induced hypertension in the borderline hypertensive rat. Eight-week-old male rats were given either electrolytic lesions of the anteroventral portion of the third ventricle region or sham lesions. All rats were then placed on a high salt diet (8% NaCl) for 10 weeks. At the conclusion of this dietary period, direct measurement of resting mean arterial pressure revealed that borderline hypertensive rats with lesions of the anteroventral portion of the third ventricle had significantly lower blood pressure (128.4 +/- 5.1 mm Hg) compared with sham-operated rats (148.1 +/- 4.1 mm Hg).

Response of intraventricular macrophages after a penetrant cerebral lesion

The response of epiplexus and supraependymal cells to extravasated blood after a penetrant cerebral lesion was investigated. Epiplexus cells respond more actively than supraependymal cells. The epiplexus cells tend to aggregate near areas of extravasation of erythrocytes, this being most marked 6 hours after injury. Epiplexus cells lose their smooth surface appearance, retract their filopodia and adopt a more spherical form, with short microvilli or blebs. Numerous inclusion vesicles develop; some contain disrupted erythrocytes 6-12 hours after injury and these are still present 24-30 hours after injury. By 8-16 days after injury epiplexus cells resume a smooth surface appearance and the number of inclusion vesicles is much reduced. This suggests reversion to a quiescent state, from an earlier active state.

Post-traumatic acute obstructive hydrocephalus

Two cases of acute obstructive hydrocephalus from intraventricular hemorrhage following head injury are presented. Each patient was involved in a motor vehicle accident and sustained closed-head trauma. Computed tomography scans revealed a fourth ventricular hematoma with obstructive hydrocephalus in each case, and both cases required emergency ventricular drainage to manage acute cerebrospinal fluid hypertension. Ventriculostomy resulted in complete recovery in the first case; however, the second patient eventually underwent ventriculoperitoneal shunting. One patient manifested an eight-hour lucid interval prior to neurologic deterioration.

Post-traumatic defects in computed tomography

Long term CT-investigations of nearly 6000 brain-traumatized patients undergoing rehabilitative measures in the past ten years, showed pathologic findings in 85-90%: 40% showed abnormalities of the ventricular system; 60% traumatic tissue lesions; and 15% abnormalities of the brain surface. Kind and frequency of occurrence of the ventricular changes found by CT were in similar to those found by pneumencephalography. Traumatic inner-hydrocephalus permagnus, which occurred in about 0.25% of our patients, is considered with regard to its rehabilitative meaning. Most traumatic defects were found in the frontal lobe (36%) or in the temporal lobe (46%). Presence and etiology of traumatic infarctions were shown in CT images in 3.5% of all traumatic cases. 25% of these were situated in the posterior area: 25% in the basal ganglia; 15% in the midcerebral artery region, and 30% were typical borderline area infarctions. Because of the frequent differences between CT-findings and neurologic or neuropsychologic symptoms, CT-findings are to be judged only in conjunction with the clinical picture. They should never serve as the only guide for the exaluation of traumatic brain defects, prescribing therapy or predicting outcome.

Successful removal of air gun bullets from the third ventricle

A patient with air gun bullets in the 3rd ventricle associated with delayed ventricular hemorrhage is presented. Through an anterior transcallosal approach, the surgeon successfully removed the bullets without any significant permanent sequelae.

The anteroventral third ventricle region. Participation in the regulation of blood pressure in conscious dogs

The anteroventral third ventricle (AV3V) region plays an important role in fluid and electrolyte balance and cardiovascular control in the rat; however, experiments in other species have raised questions about the universality of findings in the rat. The effects of discrete lesions placed within the AV3V area on hydromineral balance, the pressor response to angiotensin II given intravenously, and the initiation of a renin-dependent model of hypertension were examined in the dog. A transpharyngeal approach to the optic chiasm enabled us to destroy only the anterior aspects of the AV3V region (aAV3V group) or to include the entire nucleus medianus (NM) as well (aAV3V + NM group). Lesions of the aAV3V caused polydipsia and transient hypernatremia and hyperosmolality. In contrast, adipsia and a sustained increase in plasma sodium levels and osmolality were observed in dogs with lesions of the aAV3V plus the entire NM. Neither lesion altered baseline arterial pressure, heart rate, plasma levels of catecholamines and vasopressin, or total plasma protein levels. Only in aAV3V + NM lesioned dogs was there a tendency for plasma angiotensin II immunoreactivity to be elevated above control values at 2 and 4 days after operation. Neither lesion attenuated the pressor response to intravenous angiotension II or the initiation of renal hypertension induced by aortic coarctation. As observed in other species, structures within the AV3V region participate in hydromineral balance in the dog; however, in the dog portions of the NM dorsal to the AV3V region are essential for the mediation of drinking behavior.(ABSTRACT TRUNCATED AT 250 WORDS)

[Hemodynamic reactions to intraventricular hemorrhage]

In a 13-year girl with head injury the hemodynamic parameters during 2 episodes of intraventricular hemorrhage were monitored. There were hyperdynamic values for heart rate, Cardiac output, mean arterial and pulmonary artery pressures, systemic vascular and pulmonary vascular resistances. It is likely that centrogenic, sympathico-adrenergic reactions are the cause of pulmonary failure after isolated head injuries.

Ependymal cells of the rat fourth ventricle: response to injury

The response of ependyma to injury was investigated in rats following placement of bilateral lesions in the floor of the fourth ventricle. Animals were sacrificed from 2-60 days post-operatively and the brains were prepared in the conventional manner for comparative LM, SEM and TEM examination. For LM radioautography, randomly selected lesioned rats received either a single i.p. injection (5 muCi/g BW) or multiple injections (2 muCi/g) of 3H-thymidine prior to sacrifice. Focal disruption of the lining resulted in significant qualitative and quantitative changes in the ependyma at the wound margins. Labelling of normally quiescent ependymal cells occurred from day 2-6 post-operatively, however, the level of turnover was relatively low. Labelling was maximum on day 2 and was greater at the medial than lateral margin of the wound. During the first postoperative week, a gradual increase was observed in the number of ependymal cells per unit length at the margins of the wound concomitant with an abrupt reduction in wound diameter. This was consistent with the assumption that newly formed cells were added to the ependymal sheet at the leading edges of the wound. From 14-60 days after injury, further repair resulted from asymmetrical spreading and thinning of the ependymal sheet in the absence of mitotic activity. Quantitatively, this was reflected in a reduction in cell number at the leading edges of the wound that was most pronounced at the lateral margin. At day 60 neither epithelialization nor wound closure was complete and the normal architecture of the lining had not been fully restored. These results suggest that ependyma in the fourth ventricle of the postnatal rat undergoes a process of only limited repair following injury.

Fatal intracranial extension of an orbital umbrella stab injury

We examined a patient with an orbital stab injury with fatal intracranial extension in whom the initial emergency examination did not reveal the extent of damage. Ophthalmologic consultation showed an afferent pupillary defect (Marcus-Gunn pupil), which prompted radiologic studies. Orbital tomograms and computerized tomography demonstrated an optic canal fracture and penetration to the contralateral right ventricle. Diabetes insipidus and thermal irregularity developed, and death occurred seven days later.

Transcallosal, interfornicial approaches for lesions affecting the third ventricle: surgical considerations and consequences

A group of 11 patients with a variety of lesions affecting the 3rd ventricle have been treated using a direct transcallosal interfornicial approach to the region. In 3 patients, no attendant hydrocephalus was present. In an effort to minimize potential cortical injury related to the approach, we studied the venous anatomy in the region of the coronal suture. Based on this study, appropriate flap placement and interhemispheric entry points were defined. Although no lasting, clinically apparent morbidity was observed in any of the 11 cases, we performed more sophisticated studies of the interhemispheric transfer of somesthetic and perceptual motor tasks, as well as psychometric testing related to parameters of intelligence and memory, 3 to 8 months postoperatively in 6 cases. The results and clinical material indicate that this surgical technique is a safe, feasible alternative in the management of a wide spectrum of pathological lesions within this region. A transcallosal, interfornicial approach offers excellent visualization of the entire 3rd ventricle without the dependence on hydrocephalus or an extensive extra-axial mass to enhance the exposure. With proper planning and technique, it may be accomplished with a minimum of physiological consequence.

[Life-threatening crises of intracerebral fluid pressure induced by so-called overdrained hydrocephalus. Contribution to shunt-surgery in childhood]

The use of ventriculo-atrial shunts for the various forms of hydrocephalus can lead to an excessive drainage of cerebro-spinal fluid, resulting in a collapse or increasing obliteration of the ventricular system. This finding was confirmed in 76 children with congenital or acquired hydrocephalus who were examined by computerised axio-tomography (CAT scan). If raised intracranial pressure develops there will be symptoms of raised pressure which are discussed. The acute as well as the prophylactic management is described and the dehydrating effect of dexamethazone in children with hydrocephalus and a collapsed ventricular system is discussed.

Late recovery from head injury: case report and review

Some problems of prognosis in patients with head injury are reviewed, and a case of late and unexpected recovery from post-traumatic dementia presented. The possible mechanism of recovery is discussed with particular reference to normal pressure hydrocephalus.

Two sites of cardiovascular action of angiotensin II in the brain of the dog

1. Infusion of angiotensin into both vertebral arteries or into a lateral cerebral ventricle of dogs anaesthetized with morphine-chloralose elicited a centrally mediated rise in blood pressure.

2. Heat coagulation of the area postrema and immediately adjacent structures abolished the pressor response to infusion of angiotensin into the circulation of the vertebral arteries, but did not alter the pressor response when the peptide was delivered into a cerebral lateral ventricle; transection of the midbrain eliminated the latter response but not the former.

3. It is concluded that there are at least two areas in the dog's brain that respond to angiotensin by inducing a raised blood pressure.

Bullet within the fourth ventricle. Case report

✓ A woman, shot in the left parietal area with a small caliber pistol, appeared moribund upon admission to the emergency room but rapidly stabilized and became more arousable. In the fifth week following injury, a pneumoencephalogram demonstrated the bullet lying free within the fourth ventricle; it was subsequently removed from the cisterna magna without difficulty. The patient has made progressive neurological improvement. Other reports concerning intraventricular foreign bodies are reviewed and discussed.

Use of centrifuge in the treatment of an intraventricular metallic foreign body. Technical note

✓ A bullet fragment within the ventricular system was immobilized by use of centrifugation in a 5°-of-freedom-of-motion simulator at 4 to 6 G's. Transient cardiovascular changes occurred, but there were no ill effects clinically. The bullet fragment was immobilized within the ependyma of the left lateral ventricle and has remained in a fixed position during a 22-month follow-up period. A brief review of the treatment of intraventricular foreign bodies is included.