AKIRA ISHIBASHI, SHINKEN KURAMOTO AND HAROLD J. HOFFMAN

Transcription

1 THE KURUME MEDICAL JOURNAL Vol. 33, p , 1986 Intracranial Pressure Measurement in Newborn Infants Subependymal, Intraventricular Hemorrhage (SEH/IVH) and/or Ventriculomegaly after IVH A Preliminary Report AKIRA ISHIBASHI, SHINKEN KURAMOTO AND HAROLD J. HOFFMAN Department of Neurosurgery, Kurume University School of Medicine, Kurume, 830 Japan and *Division of Neurosurgery, Department of Neurosurgery, The Hospital for Sick Children, University of Toronto, Ontario, Canada Received for publication January 21, 1986 Summary: Subependymal Intraventricular hemorrhage (SEH/IVH) has be come of a major and important clinical entity in neonates, especially in preterm infants who are born less than 1500 gram of body weight or less than 35 weeks of gestational age. We have developed a miniaturized paper strain gauge tran sducer, which atraumatically and continuously monitors intracranial pres sure () via anterior fontanelle. Using this sensor, 22 infants SEH/IVH and/or ventricular dilatation after IVH were observed for monitoring. measurement in se infants offered useful inf otmation to assess patho physiological state of intracranical space developmental parenchyma. Key words : intracranical pressure \neonates \subependymal hemorrhage \ intraventricular hemorrhage \non-invasive monitoring Introduction Subependymal intraventricular hemor rhage (SHE/IVH) has become of a major and important clinical entity in neonates, especially in preterm infants who are born less than 1500 grams of body weight or less than 35 weeks of gestational age (Volpe, 1978). SEH/IVH occurs at rate of ap proximately 40 to 50% in 2 to 4 days of life and ventricular dilatation associated SEH/IVH has been recognized in about 40 to 80% of se infants this disease (Allan et al. 1982; Anegawa et al. 1981; Flodmark et al. 1986; Pape and Wigglesworth, 1979). Despite high frequency of ven tricular dilatation after IVH, ventricu lomegaly is produced out clinical symptomatology during first few weeks of life (Volpe et al. 1977). We had an opportunity to monitor intracranial pressure () via anterior fontanelle on 22 infants SEH / IVH and/or ventricular dilatation after IVH. This communication discribes briefly results of measurement and significance of measurement in infants SEH/IVH and/or ventricular dila tation after IVH. Materials and Methods continuously and atraumati cally monitored for 2 to 5 hours via an terior fontanelle on 22 infants SEH/ IVH and/or ventriculomegaly after IVH during sleep. 69

2 70 ISHIBASHI, ET AL. A paper strain gauge transducer applied to anterior f ontanelle while infants were asleep, and fixed by a ring three foot points which were attached on scalp around anterior f ontanelle. Oscillographic recordings were obtained in all infants. A detailed description of sensor to monitor has been reported elsewhere (Anegawa et al. 1981). Of se 22 infants who were observed for moni toring, 18 were less than 35 weeks of gestational age, and 3 were at 36 to 38 weeks of gestational age. The mean value of gestational age 26.7 weeks. The birth weight of se 22 infants ranged from 710gm to 3050gm ; 15 were less than 1500 gm of birth weight. The mean value of birth weight 1315 gm. The number of males and females even. SEH/IVH and ventricular dilatation after IVH were determined by real time ultrasound scans or CT scan, and according to de scription of Papile (1978), se 22 neo nates were classified as follows. Grade 1 : Hemorrhage confined to ger minal matrix layer Grade 2 : Intraventricular hemorrhage Grade 3 : IVH ventricular dila tation Grade 4 : Hemorrhage extended into parenchyma (Table 1). Student's "t-test" used for analysing data obtained from mon itoring. Results Real time ultrasound-scan or CT scan were repeated to determine wher ventricular dilatation after IVH and/or SEH/IVH in 22 infants in a pro gressive state or not at interval of approx imately 3 to 9 days when it iden tified at first examination. Infants were classified into 4 catego ries according to clinical signs of by- TABLE 1 Clinical data on 22 infants SEH/IVH and/or ventriculomegaly after IVH

3 INTRACRANIAL PRESSURE MEASUREMENT IN NEONATES 71 rocephalus and findings of re peated ultrasound-scan or CT scan, at time when measurements were un dertaken on se infants (Table 1). One had acute hydrocephalus, 12 had progressive hydrocephalus, 6 had arrested hydrocephalus and 3 had SEH/IVH out ventriculomegaly. Here "arrested hydro cephalus" applied for patients whose ventricles were mildly or moderately di lated at early stage of examination, but presented no furr increase in ven tricular size by comparison of equivalent section of serial ultrasound scan or CT scan, and were considered to be free from surgical intervention at time when monitored. The onset of ventricular dilatation after IVH noticed between 6 to 30 days of life (Table 1) and moni tored totally 38 times on 22 infants SEH/IVH and/or ventricular dilatation after IVH. Because of immature state of deve lopmental cerebral tissue and cerebral vascular system, arbitrarily, values obtained were provided for 2 postconceptional age groups as shown in Ta ble 2. In a group before 32 weeks of post conceptional age, in 3 infants SEH/IVH out ventriculomegaly measured 8 times in total and value (mean }SD) 2.3 }0.9 mmhg. The in se infants considered normal when followed by repeated exam inations. In 5 infants progressive hydrocephalus, monitored 6 times totally and value (mean }SD) 4.3 }1.5 mmhg. In an infant acute deteriorated hydrocephalus, ranged from 8 to 14 mmhg (Table 2). Though number of cases limited, as Fig. 1 shows, in 5 of 6 infants pro gressive hydrocephalus, values were higher than 3 mmhg, and values in 3 infants SEH/IVH out ventricu lomegaly were less than 3 mmhg. In a group before 32 weeks of postconceptional age, values in infants pro grogressive hydrocephalus were signifi cantly highet than in infants SEH/ IVH out ventriculomegaly (p<0.01). In a group after 32 weeks of post- TABLE 2 ualues (mean }SD) in 22 infants are shown, who are divided into two group, i, e., before and after 32 weeks of postconceptional age

4 72 ISHIBASHI, ET AL. Fig. 1. Comparison of values in 22 infants SEH/IVH and/or ventriculomegaly after IVH. Fig. 2. and ultrasound scan in an infant acute hydrocephalus before 32 weeks of postconceptional age.

5 INTRACRANIAL conceptional in age, each of 6 hydrocephalus. 6.9 }3.5 cal infants and once value arrested mmhg. progressive value There in two 15 times (mean }SD) also in a values statisti obtained (p<0.05). So far as occurrence of pressure wave in on 22 infants concerned, small plateau type waves, though not just like Lundberg's A type wave (Lundberg, 1960), appeared in an infant acute hydrocephalus before 32 weeks of post- Fig. 3. and ultrasound after 32 weeks of postconceptional Upper Upper scan in an age. age and progressive weeks hydro IN NEONATES conceptional (mean±sd) monitored significance between measured MEASUREMENT mmhg. 7 cephalus, total infants The 4.0 }1.7 In PRESSURE of in 73 4 of hydrocephalus conceptional 7 infants after 32 age. In an infant acute hydrocephalus whose fontanelle extremely tense and bulging, and lethargic under artificial respiration, baseline pressure of 8 mmhg, but increased rapidly, and represented a small plateau type wave peak value of 14mmHg (Fig. 2). These values might be considered to be mild hypertensive intracranial pressure in older children and adults. With duration of minutes, began to fall to previous level of height. Four infant of left: at time when monitored. right: 6 days after measurement. Marked confirmed. 7 infants progressive increase progressive hydrocephalus in ventricular size

6 74 ISHIBASHI, ET AL. hydrocephalus after 32 weeks postconce ptional age had small plateau type waves. The peak value of this wave obtained in se infants ranged from 8 to 18 mmhg duration of 5 to 10 minutes. In one of 4 infants, though base line pressure of 8 mmhg, began to increase insidiously, forming small plateau type wave peak value of 18 mmhg, and 10 minutes later, began to decrease to previous level of height. At this time ventricu lar size considered to be normally by ultrasound scan. About 6 days after measurement, increase in head cir cumference of this infant noticed at a rate of 1 cm in 2 days, and later progression of ventriculomegaly con firmed by ultrasound scan (Fig. 3). This rapid change in not identified in rest of infants examined our sensor. Discussion In recent years, using noninvasive real time ultrasound scan, it has become common and important to detect SEH/IVH and/or ventricular dilatation after IVH in preterm infants. It is generally accepted that SEH/IVH occurs approximately 40 to 50% of preterm infants in 2 to 4 days of life (Volpe, 1978). Ventricular dilatation is frequently i dentif ied secondary to SEH/IVH and ap proximately 40 to 80% of infants SEH/IVH have it in one to 3 weeks after SEH/IVH (Allan et al. 1980, 1982; Flodmark et al. 1986; Pape and Wigglesworth, 1979). But, it is not easy to identify clinically wher ventricular dilatation may become progressive or not, because in most new born infants SEH/IVH, increase in ventricular size occurs out clinical manifestation of hydrocephalus (Korobkin, 1975). We have developed a miniaturized paper strain gauge transducer, which atraumatically and continuously monitors via anterior fontanelle in newborn infants (Anegawa, 1981). Using this sen sor, 22 infants SEH/IVH and/or ven tricular dilatation after IVH were observed for monitoring TOP. In a group before 32 weeks of postcon ceptional age, TOP value (mean }SD =4.3 } 1.5 mmhg) in infants progressive hydrocephalus were significantly higher than value (2.3 }0.9 mmhg) in infants SEH/IVH out ventriculomegaly (p<0.01). in latter infants considered as normal value when followed by repeated examinations. In previous studies (Ishibashi, 1982), TOP measured 28 times totally on 7 preterm infants born at gestational age of 33 to 38 weeks, who did not have evidence of disease of central nervous system when monitored our sensor. In se 7 normal preterm infants, TOP value (mean }SD) 5.7 }2.3 mmhg. When TOP value in 7 normal preterm infants compared that of infants SEH/IVH out ventriculomegaly, re a remarkable pressure gradient between two in relation age. This implied that TOP in preterm infants, who have immature, but developmental cerebral parenchyma and environment sur rounding it, might increase physiologically in relation to age, just as systemic blood pressure and cerebral perfusion pressure in preterm infants increase age (Raju et al. 1982). It considered reasonable that post conceptional age should be taken into con sideration when TOP values were compared among infants, especially preterm infants. Therfore, it might be stated that when TOP values in infants before 32 weeks of postconceptional age show more than 3 mmhg, this might mean an increased TOP and also be an early diagnostic signifi cance among infants vith ventricu lomegaly after IVH, though value

7 INTRACRANIAL PRESSURE MEASUREMENT IN NEONATES 75 considered in normal limits when compared normal preterm infants as described above. Hill et al. (1981) have shown that re a progressive increase in ventricular dilatation out an increase in, i. e., normal pressure hydrocephalus in infants IVH LARD f ibroptic sensor. In present study, almost same result obtained when values of 7 infants progressive hydrocephalus after 32 weeks of postconceptional age were compared those of 7 normal preterm infants. So far as pressure wave in concered, rapid change in, i, e., small plateau type wave identified, our sensor in an infant hydrocephalus before 32 weeks of postconceptional age and in 4 of 7 infants progressive hydrocephalus after 32 weeks of postcon ceptional age. This chage in never identified among normal preterm infants when examined in previous study (Ishibashi, 1982), and also this phe nomenon not noticed in rest of infants in present study eir. Ventricular dilatation may result not only from disurbance of CSF flow caused by arachnoiditis in pos tenor f ossa or adueductal stenosis after IVH, but also from cerebral atrophy caused by impairment in cerebral cir culation to especially periventricular region secondary to hypotension during hypoxic and apneic attacks in preterm infants (Flodmark et al. 1986; Pape and Wigglesworth, 1979). Hill et al. (1981) have described mechanism of increase in ventricnlar size in newborn infants NPH, after IVH. They considered net increase of CSF which may be caused by dis turbance of CSF flow, produced ventricul omegaly out an increase in, be cause compliance of periventricular tissue is increase due to its immature state of developmental cerebral tissue and/or prior hypoxic ischemic injury. We agree ir concept and in addition, it may be stated that ventriculomegaly produces structural changes in cerebral parenchyma followed by loss of fluid from cerebral parenchyma (Hakim et al. 1976), refore, compliance of developmental cerebral parenchyma be comes decreased in accordance increase in ventriculomegaly and, as long as increase in ventricular size is con tinued, re needs more increase in against decreased compliance of cerebral parenchyma. Though mechanism of develop ment of small plateau type wave in pre term infants is not well known, inter mittent occurrence of small plateau type may play an important role in continuing to increase ventricular size and this may increase its value until limit of compliance of cerebral parenchyma is reached, when clinical signs of hydrocephalus begin to manifest so called increased. Conclusion measurements in infants SEH /IVH and/or ventricular dilatation after IVH offered useful information to assess pathophysiological state of intrac ranial space developmental cerebral parenchyma. References ALLAN, W. C., HOLT, P. J., SAWYER, L. R., TITo, A. M, and MEADE, S. K. (1982). Ventricular di latation after neonatal periventricular-intra ventricular hemorrhage. Am. J. Dis. Child. 136, ALLAN, W. C., ROVETO, C. A., SAWYER, L. R. and COURTNEY, S. E. (1980). Sector scan ultrasound imaging through anterior fontanelle. Am. J. Dis. Child. 134,

8 76 ISHIBASHI, ET AL. ANEGAWA, S., HAYASHI, T., ISHIBASHI, A., HONDA, E. OHSHIMA, Y., KURAMOTO, S. and HASHIMOTO, T. (1981) Clinical significance of measure ment in infants: comparative investigations on normal and abnormal infants. Nervous System in Children, 6, FLODMARK, O., ScoTTI, G. and HARWOOD-NASH, D. C. (1986). Clinical significance of ventricu lomegaly in children who suffered perinatal asphysia or out intracranial hemor rhage : An 18 month followup study. J. Comput. Assist. Tomogr. (in press) HAKIM, S., VENEGAS, J. G. and BURTON, J. D. (1976). The physics of cranial cavity. Hydro cephalus and normal pressure hydrocephalus. Mechanical interpretation and mamatical model. Surg. Neurol. 5, HILL, A, and VOLPE, J. J. (1981). Normal pressure hydrocephalus in newborn. Pediatrics, ISHIBASHI, A. (1982). A study on measure ment of intracranial pressure via anterior f ontanelle \ particular emphasis on fluctuations of intracranial pressure among newborn infants and operative indication a mong hydrocephalic cases. J. Kurume Medical Association, 45, KOROBKIN, R. (1975). The relationship between head circumference and development of communicating hydrocephalus in infants fol lowing intraventricular hemorrhage. Pedi atrics, 56, LUNDBERG, N. G. (1960). Continuous recording and control of ventricular fluid pressure in neurosurgical practice. Acta Psychiat. Neurol. Scand. 36, 149. PAPILE, L. A., BURSTEIN, J., BURSTEIN, R, and KOFF LER, H. (1978). Incidence and evolution of subependymal and intraventricular hemor rhage: A study of infants birth weights less than 1, 500 gm. J. Ped. 92, PAPE, K. E. and WIGGLESWORTH, J. S. (1979). Hemorrhage, ischemia and perinatal brain. Philadelphia; Lippincott Co. RAJU, T. N. K., DOSHI, D. V. and VIDYASAGAR, D. (1982). Cerebral perfusion pressure studies in healthy preterm and term newborn infants. J. Ped. 100, VOLPE, J. J., PASTERNAK, J. F. and ALLAN, W. C. (1977). Ventricular dilation preceding rapid head growth following neonatal intracranial hemorrhage. Am. J. Dis. Child. 131, VOLPE, J. J. (1978). Neonatal periventricular hemorrhage : Past, present and future. J. Ped. 92,