Normotensive Hydrocephalus Research Articles

Is the blood-CSF barrier altered in disease?

To illustrate the influence of cerebrospinal fluid (CSF) flow on lumbar CSF protein concentration and to test for an altered blood-CSF barrier permeability as additional influence. Consecutively hospitalized patients with normotensive hydrocephalus (n = 21) underwent lumbar puncture with CSF being sampled in sequential portions. CSF/blood quotients of albumin (QAlb) and of immunoglobulin G (QIgG) were compared intra-individually and with calculated values from a reference patient sample. QAlb and QIgG of intra-individual sequential portions correlated highly with each other (median r = 0.95), suggesting lumbar CSF flow as the main thecal determinant of lumbar QAlb and QIgG variation. In addition, QIgG, relative to QAlb, was significantly lower in study patients compared with a reference patient sample (P = 0.002), implying an alteration of the blood-CSF barrier permeability as a minor determinant of QAlb and QIgG variation in study patients.

Review: treatment of hydrocephalus in adults

Hydrocephalus is a major province of neurosurgery because of its high incidence and the still unacceptably high rate of complications that plague all shunting devices (SD). Countless shunts have been designed, some of them rather complex and expensive; however, results continue to be far from satisfactory, indicating that much research is still needed. Hydrocephalus in children is mainly due to congenital abnormalities, whereas hydrocephalus in adults is caused by several different etiopathological conditions; for instance, two frequent forms of primary hydrocephalus in adults are due either to chronic active arachnoiditis or to normotensive hydrocephalus, both of which are almost never seen in children. These two conditions present peculiar challenges for the design of adequate shunting devices. In this review the main aspects of the treatment of hydrocephalus in adults are outlined, stressing principal indications, treatment alternatives, and common complications.

AUTOMIC FAILURE AND NORMAL PRESSURE HYDROCEPHALUS IN A PATIENT WITH CHRONIC DEMYELINATING INFLAMMATORY NEUROPATHY

A 75‐year‐old man with HCV hepatitis developed at the age of 70 presented with rest and action tremor localized at both hands and progressive cognitive impairment with memory loss. Four years later he begun to complain of progressive fatigue, occasional falls, numbness at the extremities and orthostatic hypotension. One month after admission, he rapidly worsened with inability to walk, mainly because of autonomic failure. Neurological examination revealed gait disturbances, including a wide base of support and short stride, slurred speech, reduction of upward gaze, rest and action tremor at both hands, intrinsic hand muscle and anterior tibialis muscle wasting and weakness on both sides, absent deep tendon reflexes, loss of vibration sense at lower limbs, and bilateral pes cavus. Routine laboratory studies, autoantibodies, thyroid function, neoplastic markers and immunoelectrophoresis were normal. Cryoglobulins were absent, whereas CSF protein content was increased (142 mg/dl). Autonomic nervous system investigation detected severe orthostatic hypotension. Nerve conduction studies showed absent sensory potentials and a marked reduction of compound motor action potential amplitudes and of motor conduction velocities. A sural nerve biopsy revealed remarkable onion bulb‐like changes, endoneurial and perivascular infiltrations of inflammatory cells. Psychometric tests showed mild cognitive impairment. Brain MRI was consistent with normotensive hydrocephalus. The findings indicated the presence of chronic inflammatory demyelinating polyneuropathy, autonomic nervous system involvement and normal pressure hydrocephalus. A condition of multiple system atrophy (MSA) might be taken into account, even if somatic peripheral nerve involvement may rarely occur in MSA. Moreover the normal pressure hydrocephalus could be due to the high protein content in CSF (Fukatsu R et al., 1997).

39-39 - Idlopathic normotensive hydrocephalus as a potentially reversible cause of dementias in later life

39-39 - Idlopathic normotensive hydrocephalus as a potentially reversible cause of dementias in later life

P321 Somato-sensory evoked potentials in hypertensive and normotensive hydrocephalus

P321 Somato-sensory evoked potentials in hypertensive and normotensive hydrocephalus

Primary progressive freezing gait.

Freezing gait is an incapacitating symptom often observed in patients with Parkinson's disease. It has been less frequently described in association with multi-infarct state, multisystem atrophies, and normotensive hydrocephalus. In our movement disorder clinic, we have diagnosed (and followed up to 3 years; median, 16 months), 18 patients in whom progressive freezing gait was the sole neurological dysfunction. These 15 men and 3 women (aged 60-82 years; 74 +/- 6) were subjected to an extensive neurological workup that included clinical evaluation, videotaping for grading of gait disability, comprehensive blood and cerebrospinal fluid (CSF) analysis, and brain computed tomography (CT) and magnetic resonance imaging (MRI). Mean disease duration was 2.5 +/- 1.9 years (range, 0.5-6). Neurological examination disclosed freezing gait, often associated with varying degrees of postural instability. The degree of freezing gait ranged from sudden motor blocks only when confronted with obstacles to severe disability with total inability to start walking requiring a walker, massive assistance, or a wheelchair. However, patients could mimic gait movements with absolutely no freezing when seated or lying prone, and most of them could overcome arrests by the "walking-over-lines" maneuver. Otherwise, neurological examination was normal with no signs of bradykinesia, rigidity, or tremor. Blood chemistry and CSF analysis were normal. Brain CT and MRI were normal or showed mild cortical atrophy in 12 and putative lacunes in 6 patients. Therapy with levodopa or dopamine agonists was ineffective. During the follow-up period, a gradual progression of the freezing gait was observed. However, it remained unaccompanied by any other neurological findings.(ABSTRACT TRUNCATED AT 250 WORDS)

Time course of intraventricular pressure change in a canine model of hydrocephalus: its relationship to sagittal sinus elastance.

Hydrocephalus was induced in adult greyhounds by intracisternal kaolin. Intraventricular pressure (IVP) was monitored in the conscious animal for 2 weeks using a small implantable sensor, and the time-course of IVP change was characterized. Intraventricular pressure increased significantly within 36 h of kaolin infusion and gradually subsided to normal values within 1 week. Enlargement of the lateral ventricles was not observed during the early phase of intracranial hypertension (less than 2 days). Evolving hydrocephalus and intracranial hypertension increased the elasticity (dP/dV) of the sagittal sinus. This effect was statistically significant (p < 0.05) and is possibly reversible in the acute stage. Normotensive hydrocephalus (1 and 2 weeks after kaolin) was associated with an irreversible increase in resistance to outflow (i.e., increased sagittal sinus elasticity). Sagittal sinus venography of animals with obvious ventricular enlargement (at least 1 week after kaolin) showed development of venous collaterals and atypical outflow pathways.

The Role of Alertness in Organic Brain Syndromes

We examined 35 patients, aged from 37 to 76 years, with impairment of intellectual functions due to normotensive hydrocephalus of varied origin. Axial tomography showed an enlarged ventricular system, with or without cortical atrophy. As a rule, the patients having no cortical atrophy displayed a significantly lower alertness level than the patients with cortical atrophy, who were more alert. Because the clinical picture was similar in both subgroups, it was postulated that the impairment of cortical function due to organic lesions resulted in symptoms similar to those due to chronic decrease of alertness. According to this hypothesis, there are two types of symptoms in patients with organic brain syndromes, one type being dependent on the alertness decrease and not on the organic lesion itself. Although the two types cannot be easily distinguished during clinical examination, the prognosis is substantially different for "organic" and "functional" symptoms. The hypothesis was supported by observations in 19 patients selected for ventriculoperitoneal shunt operation. Reexamination 3 months after the operation showed that the improvement was not related to changes in the organic substrate, i.e., to the diminished size of the lateral ventricles and of the third ventricle. On the other hand, the clinical improvement was significantly correlated to the increase of the alertness level after treatment.

Intracranial pressure behaviour and its relation to the outcome of surgical CSF shunting in normotensive hydrocephalus.

Twenty-four patients with suspected normotensive hydrocephalus were surgically treated by cerebrospinal fluid (CSF) ventriculoatrial or peritoneal shunt. The results of surgery were considered in relation to clinical history and different diagnostic examinations: pneumoencephalography, CT scan, isotope cisternography, transfer from CSF to blood of isotope-labelled serum albumin, constant infusion manometric test, intraventricular pressure recording. Intracranial pressure (ICP) was analysed during both resting conditions and spontaneously (REM phase of sleep) or artificially induced (jugular compression) increases. The ventricular enlargement (as shown by CT scan) and the slope of the intracranial elastance (the ratio of the differences between the maximum and minimum values of pulse ICP and the correspondent values of the diastolic ICP under the same dynamic conditions) provided the most reliable data for diagnosis and surgical prognosis.

Sequential morphological and functional changes in kaolin-induced hydrocephalus.

An experimental model of kaolin-induced hydrocephalus in the dog was studied in order to evaluate the progress of ventricular dilatation and the communications between the ventricular system and the subarachnoid space. Skull and spine radiological studies were obtained after metrizamide intraventricular injection, and the baseline ventricular pressure and cerebral pulse pressure amplitude were measured in anesthetized animals. Intracranial compliance and resistance to drainage of cerebrospinal fluid were calculated by means of bolus injection test. Light and scanning electron microscope studies were done at different developmental stages of hydrocephalus. With these experimental parameters, two successive phases were seen: an initial acute hypertensive hydrocephalus (H1) with high resistance, low compliance, severe ependymal damage, and subependymal edema; and a late chronic normotensive hydrocephalus (H2) with little resistance increase, normal compliance, epithelial regeneration, and subependymal gliosis. Both the H1 and H2 stages showed an increase in the cerebral pulse pressure amplitude.

Hydrocephalus in Infancy and Childhood: Diagnosis and Indication for Operation

Improvement of the prognosis for children suffering from hydrocephalus requires prompt diagnosis and reliable indication of surgical treatment. Today, intrauterine hydrocephalus is detectable within the first three months of pregnancy; in infancy, before the cranial sutures have fused, pathological growth of the head is the principal sign confirming together with anatomical examinations (ultrasound, CT scan) the indication of operative treatment. In later childhood, surgical treatment is only definitely indicated by symptoms and morphological examination of clearly active hypertensive hydrocephalus. Intermittently normotensive hydrocephalus (not "normal-pressure-hydrocephalus"!) showing symptoms adapted to childhood, however, often requires exact examination of intracranial pressure dynamics, including quantitative volume provocation test. "Step-by-step-procedure" is advisable (Table III).

Measurement of 111in DTPA clearance during radionuclide cisternography.

A new preparation of 111In DTPA for intrathecal administration has been tested and found to be a safe and highly efficacious cisternographic agent. The rate of removal of 111In DTPA from the C.S.F. and from the whole body has been measured and has been found to be of no diagnostic value in the distinction between patients with cerebral atrophy and those with normotensive hydrocephalus. Long-term retention studies show no evidence of significant long-term retention of indium in the C.S.F. The absorbed radiation dose has been investigated and found to be in good agreement with previous estimates based upon extrapolated data.

Anatomo-clinical correlations in normotensive hydrocephalus: Reports on three cases

The brains of 3 adult subjects suffering from normotensive hydrocephalus have been examined pathologically. The diagnosis of normotensive hydrocephalus was based on clinical symptoms, pneumoencephalography and isotope cisternography, in 1 case integrated with the results of the constant-infusion manometric test. Part of the neuropathological findings were common to the 3 patients: leptomeningeal non-obstructive fibrosis, ventricular ependymal disruption, subependymal glial reaction, periventricular demyelination and spongiosis. Other neuropathological abnormalities were peculiar to each patient: leptomeningeal signs of previous subarachnoid haemorrhage; arteriosclerosis and multiple brain cystic infarcts; Alzheimer's plaques in the gray matter. The possible pathogenetic significance of the neuropathological findings summarized above in relation to the development of normotensive hydrocephalus is discussed.

Surgical indications in normotensive hydrocephalus. A retrospective analysis of the relations of some diagnostic findings to the results of surgical treatment.

Twenty two of fifty five patients initially suspected of suffering from normotensive hydrocephalus were surgically treated (CSF ventriculoatrial shunt). The results of surgery were related to the findings of the different diagnostic examinations (pneumoencephalography, isotope cisternography, transfer fron CSF to blood of isotope labelled serum albumin, constant infusion manometric test, long lasting intraventricular pressure recording). 1.Pneumoencephalography, intraventricular pressure recording, and, above all, isotope cisternography provided the most reliable data for diagnosis and surgical prognosis. 2. The combined use of pneumoencephalography and isotope cisternography was sufficient for a correct diagnosis and surgical prognosis in about 50% of the patients examined. 3. When the diagnostic information given by the combined results of the two above examinations was not sufficient, intraventricular pressure recording proved to be the most useful examination to supplement it. 4. The relation of the results of the study of transfer of istope labelled serum albumin from CSF to blood and of the constant infusion manometric test to the surgical outcome was uncertain.

Occult disorders of the cerebrospinal fluid dynamics. Early diagnosis criteria.

Workable criteria are proposed that allow early recognition of mild forms of occult hydrocephalus and correlated disorders. Two groups of patients are analyzed, i.e., a group of twelve mild but classical forms of low-pressure hydrocephalus and another group of 20 patients with atypical clinical forms of disorders of the CSF dynamics. Two control groups are presented for neuropsychological comparison purposes: a normal control group of 50 subjects and a small group of three commissurotomized subjects. Patients with an overt demential syndrome due to a normotensive hydrocephalus syndrome were excluded from the study. The authors found the grasp reflex of the foot and the tonic foot response to be present in all cases with the Hakim and Adams triad. In such cases the grasp reflex is usually accompanied by the forward groping of the foot and the grasp reflex of the hand. The most helpful and useful clinical findings for an early diagnosis are the presence of the grasp reflex of the foot and of the tonic foot response of the sole in such organic brain-damaged patients with (1) a normal routine neurological examination and (2) an apparently normal mental status and even with a rather normal IQ. These reflexes are usually the single objective clinical findings in all forms of mild and occult disorders of the CSF dynamics, i.e., low-pressure hydrocephalus syndromes, cerebral atrophies and mixed forms cases. The next step for the diagnosis consists in a conventional IQ evaluation and a battery of tests exploring more specifically the sensorimotor integration, i.e. bimanual vs. unimanual activity, the Kohs block design test and part of the Halstead-Reitan neuropsychological test battery.

Normotensive hydrocephalus. The relations of pneumoencephalography and isotope cisternography to the results of surgical treatment.

An attempt has been made to evaluate the prognostic value for surgery of some diagnostic findings in 15 patients with normotensive hydrocephalus. The results of CSF surgical shunting were considered in relation to the results of pneumoencephalography and isotope cisternography with I131 HSA. In addition, the data obtained by the estimation of the transfer of isotope labelled serum albumin from CSF to blood have been considered. Ten patients showed remarkable improvement following surgery, five did not. From the results of the present study it appears that no one of these diagnostic investigations gives a reliable surgical prognosis which may, however, be obtainable by integrating the results of the different examinations. The following combination of findings appears highly suggestive of good surgical prognosis: ventricular enlargement and everted anterior medullary velum with no signs of cerebral atrophy in the pneumoencephalogram, plus ventricular filling in the isotope cisternographic scans. The additional finding of retention of the isotope labelled serum albumin may further strenghthen the prognostic information.

Chronic Listeria monocytogenes meningitis and normotensive hydrocephalus. Case report and review.

Chronic Listeria monocytogenes meningitis and normotensive hydrocephalus. Case report and review.