Normal CSF Pressure Research Articles

Cerebrospinal fluid hydromechanics in adult patients with benign noncommunicating hydrocephalus: one-hour test shunting and balanced cerebrospinal fluid infusion test to select patients for intracranial bypass operation.

Cerebrospinal fluid (CSF) pressure and absorption were determined in 12 patients with benign noncommunicating hydrocephalus. An extracorporeal communication of plastic tubing between the ventricular system and the lumbar subarachnoid space was established to imitate the hydromechanical condition after an intracranial bypass operation. This extracorporeal shunt, which in effect was an externalized Torkildsen shunt, served first as a test shunt for 1 hour and then as a route for the constant rate CSF infusion test. The total CSF absorptive capacity was thus determined under a condition of balanced CSF pressure between the proximal and distal compartment. Four patients, whose tests showed normal CSF pressure and absorption, were selected for intracranial bypass operation. Follow-up examination showed a normal clinical condition, reduction of the ventricular system, normal CSF pressure, and normal CSF absorption in all 4 patients. The other 8 patients, whose tests indicated impaired CSF absorption, were treated by ventriculoatrial shunting. The tests were valid in selecting patients for intracranial bypass operation.

Hydrocephalus following removal of cerebellar astrocytomas in children.

✓ Of 150 children undergoing surgery for cerebellar astrocytoma, 20% had evidence of postoperative hydrocephalus. This was manifested by either progressive symptomatic rise in intracranial pressure or abnormal mental and motor states accompanied by normal CSF pressure. This syndrome is presumed to be due to cisternal and subarachnoid adhesions formed after surgery. Prompt shunting in advanced cases resulted in reversal of neurological abnormalities.

Hidrocéfalo com pressão normal, tipo Hakim-Adams

O hidrocéfalo com pressão normal do LCR, estudado por Hakim e Adams e colaboradores, é caracterizado por demenciação rapidamente progressiva associada a distúrbios da marcha, sinais piramidais e extrapiramidais, e evolução para um estado final semelhante ao do mutismo acinético, com incontinencia esfincteriana, torpor e coma. Os autores apresentam o caso de um paciente de 61 anos de idade no qual se desenvolveu, no período de dois anos, enfermidade inicialmente marcada por distúrbios da marcha, seguidos de deterioração mental de evolução rápida, sinais piramidais nos quatro membros, incontinência esfincteriana, astasia-abasia. Não foram assinalados antecedentes de traumatismos crânio-encefálicos com ou sem hemorragia sub-aracnóidea, de meningite, de ence-falite ou de neoplasia. Os exames radiológicos mostraram grande hidrocéfalo comunicante. O paciente foi submetido a intervenção cirúrgica, sendo feita derivação ventrículo-atrial direita com interposição de válvula de Icon. O pós-operatório foi marcado por melhora rápida dos sintomas mentais e motores. Reexaminado cinco meses após o ato cirúrgico, o paciente continuava em bom estado, tendo voltado às suas atividades profissionais.

The special clinical problem of symptomatic hydrocephalus with normal cerebrospinal fluid pressure: Observations on cerebrospinal fluid hydrodynamics

In a series of personally observed cases, three of which are reported in detail, the authors have noted that a state of symptomatic hydrocephalus may exist in the presence of normal CSF pressure. The patients had exhibited mental dullness, inattentiveness, psychomotor retardation, unsteadiness of gait, and incontinence of urine, a syndrome which may be mistakenly ascribed to a degenerative or traumatic vascular disease of the cerebrum. Ventriculo-atrial shunt corrected this condition and permitted recovery by lowering the CSF pressure 20 or more mm of water. An important factor, heretofore overlooked, in explaining this symptomatic hydrocephalus with relatively normal CSF pressure is that the force exerted on the ventricular wall represents a product of pressure times surface area. A given pressure exerts a greater force in a large ventricular system than in a small one. A pressure of 170 or 180 mm H 2O in ventricles that are three times normal size may produce symptoms, whereas it would not do so in a normal-sized ventricular system. This hydraulic press hypothesis must be applied in all cases of hydrocephalus. Without some knowledge of ventricular size in this condition, the CSF pressure cannot be accurately evaluated. This physical principle applies not only to adult hydrocephalus but also to infantile hydrocephalus, where the cranium expands, and to certain types of porencephaly and postoperative meningeal cysts and possibly syringomyelia.