Early hyperdopaminergic state following sub-thalamic nucleus deep brain stimulation in Parkinson disease

BACKGROUND

Hyperdopaminergic state (HS), especially impulse control behaviors (ICBs), are not rare in Parkinson's disease (PD). Controversial data regarding HS prevalence one year following sub-thalamic nucleus deep brain stimulation (STN-DBS) are reported.

OBJECTIVE

Our objectives were to describe early postoperative HS (PoOHS) including ICBs, hypomania and psychotic symptoms during the first 3 months following STN-DBS (V1) and their prognosis at 1 year (V2).

METHODS

This descriptive study included 24 PD patients treated successively with bilateral STN-DBS between 2017 and 2019. The primary endpoint was prevalence of PoOHS at V1 according to the Ardouin Scale of Behaviour in Parkinson's Disease.

RESULTS

Prior to STN-DBS (V0), 25% patients had HS (only ICBs) whereas at V1 (during the 3 first months), 10 patients (41.7%) had one or several HS (P=0.22) (de novo in 29.2%): 7 (29.2%) ICBs, 4 (16.7%) hypomanic mood, 1 (4.7%) psychotic symptoms. At V2, all V0 and V1 HS had disappeared, while 1 patient (4.2%) presented de novo HS (P<0.01). No correlation was found between the occurrence of PoOHS at V1 and any V0 data. Higher levodopa equivalent dose of dopamine agonists at V1 was correlated with ICB at V1 (P=0.04).

CONCLUSION

We found that early PoOHS are frequent in PD after STN-DBS, mostly de novo, with ICBs and hypomania being the most frequent. Despite a good prognosis of PoOHS at one year, our work emphasizes the importance of both a cautious adjustment of dopamine agonist doses and a close non-motor monitoring pre- and post-STN-DBS in PD.

P14.87 Leptomeningeal dissemination in high grade glioma: Correlation of MRI, cytology and standard CSF indices

BACKGROUND

Only few studies report the incidence of leptomeningeal dissemination (LMD) in patients with high grade glioma (HGG), although LMD is not a rare condition of recurrence. We aimed to describe the diagnostic features and treatment modalities in a series of patients treated for HGG in our institution.

METHODS

Review of clinical presentation, radiological features and CSF analysis in a case series.

RESULTS

17 patients from our institution were diagnosed with LMD. The diagnosis of LMD was based on magnetic resonance image and/or cerebrospinal fluid (CSF) analysis. The spectrum of clinical presentation was broad, mainly intracranial hypertension, impaired general condition, pain, worsening of pre-existing symptoms, and epileptic seizures. Median time from onset of clinical deterioration to diagnosis of LMD was 3 weeks (0–16). Leptomeningial involvement was reported in 6/17 at initial MRI reading, whereas reassessment with careful comparison to previous MRI showed signs of LMD in all patients. CSF analysis revealed pleocytosis (11/17), high proteinorrachia (13/17), elevated lactate levels (15/16), low glucose levels (5/17), and increased CSF pressure (5/9). Nevertheless, diagnostic accuracy of initial CSF cytological analysis was low (2/17). A reassessment of the specimen by an experienced neuropathologist disclosed 1 additional positive and 1 additional suspect cytology. After diagnosis of LMD, salvage treatments comprised Bevacizumab, Lomustine, Fotemustine, liposomal cytarabine and best supportive care. The median overall survival after the diagnosis was 3 months.

DISCUSSION AND CONCLUSIONS

LMD in HGG is not a rare condition of recurrence, and its outcome is poor. It remains a diagnostic challenge, as it may be overlooked on MRI follow-up at its early stage. In case of clinical progression with no overt cause reported on MRI, we recommend careful second MRI reading. In case of doubt lumbar puncture should be performed in order to prove LMD and eliminate infection (i.e. HSV). Upon standard CSF indices, elevated lactate levels should give rise to the suspicion of LMD. Cytological CSF analysis seems to be of low diagnostic yield: This may be improved by faster processing after sampling and by standardized workup including staining with IDH, GFAP and Olig2.

OS1.3 Tumor cell-free DNA detection in CSF for primary CNS lymphoma diagnosis

BACKGROUND

Primary CNS lymphoma (PCNSL) is a rare disease accounting for around 3% of the primary brain tumors. In the vast majority of cases, PCNSL are classified as diffuse large B-cell lymphoma according to the WHO classification. The diagnosis is based on cranial MRI, in combination with a brain biopsy. In case of classical MRI findings, the identification of lymphoma cells in the cerebrospinal (CSF) or vitreous fluid by cytology and flow cytometry might obviate brain biopsy. The presence of the somatic mutation p.Leu265Pro (L265P) in MYD88 is detectable in 50 to 80% of PCNSL, and might also be helpful to confirm the diagnosis. The aim of our study was to evaluate the contribution of a highly sensitive digital droplet PCR, targeting the mutation L265P MYD88, for the detection of tumoral circulating DNA from CSF supernatant.

MATERIAL AND METHODS

We identified 9 PCNSL expressing the L265P mutation at diagnosis or relapse. The mutation was found by an allele specific PCR technique either on biopsy or in CSF cells. Circulating DNA was isolated from CSF supernatant with the « QiaAmp® circulating nucleic acid» kit. The quantity of DNA collected was estimated by quantitative PCR for a reference gene (albumine) with 7900HT (Life technologies™) device. Subsequently, the L265P MYD88 mutation was quantified by digital droplet PCR Biorad™: The droplets generated were amplified by PCR, detected with the QX200 Reader, and analyzed with the QuantaSoft™ software.

RESULTS

The circulating DNA concentration was low, varying between 0 and 2.2 ng/mL of CSF. However, the mutation was detected in the circulating DNA from CSF supernatant in 6 out of 9 cases (66%). The fractional abundance varied from 2.6 to 85%. In 3 cases, the mutation was detected even though cytology and flow cytometry did not reveal leptomeningeal disease. For 3 other cases, the mutation was not detected: The genome copy number was below 1 copy/µL, indicating a low analytical sensitivity for theses samples.

CONCLUSION

This study shows that circulating DNA is present in low concentration in CSF and can be amplified by a sensitive digital PCR for the L265P MYD88 mutation. The detection of circulating PCNSL DNA in CSF is possible and might be used to improve the non-invasive diagnosis of PCNSL. It might also help to select patients for targeted therapies.

Association of combined GIF290T>C heterozygous mutation/FUT2 secretor variant with neural tube defects

Folate and vitamin B12 are needed for the proper embryo-fetal development possibly through their interacting role in the 1-carbon metabolism. Folate fortification reduces the prevalence of complex birth defects, and more specifically neural tube defects (NTDs). GIF and FUT2 are 2 genes associated with the uptake and blood level of vitamin B12. We evaluated GIF and FUT2 as predictors of severe birth defects, in 183 aborted fetuses compared with 375 healthy newborns. The GIF290C allele frequency was estimated to 0.4% in healthy newborns and to 8.1% in NTD fetuses (odds ratio 17.8 [95% confidence interval CI: 4.0-77.6]). The frequency of FUT2 rs601338 secretor variant was not different among groups. The GIF 290C heterozygous/FUT2 rs601338 secretor variant combined genotype was reported in 6 of the 37 NTD fetuses, but not in other fetuses and healthy newborns (P < .0001). This GIF/FUT2 combined genotype has been previously reported in children with congenital gastric intrinsic factor (GIF) deficiency, with respective consequences on B12 binding activity and GIF secretion. In conclusion, a genotype reported in congenital GIF deficiency produces also severe forms of NTD. This suggests that vitamin B12 delivery to neural tissue by the CUBN/GIF pathway could play a role in the neural tube closure mechanisms.

Multicolumn spinal cord stimulation for significant low back pain in failed back surgery syndrome: design of a national, multicentre, randomized, controlled health economics trial (ESTIMET Study)

BACKGROUND

Many studies have demonstrated the efficacy of spinal cord stimulation (SCS) for chronic neuropathic radicular pain over recent decades, but despite global favourable outcomes in failed back surgery syndrome (FBSS) with leg pain, the back pain component remains poorly controlled by neurostimulation. Technological and scientific progress has led to the development of new SCS leads, comprising a multicolumn design and a greater number of contacts. The efficacy of multicolumn SCS lead configurations for the treatment of the back pain component of FBSS has recently been suggested by pilot studies. However, a randomized controlled trial must be conducted to confirm the efficacy of new generation multicolumn SCS. Évaluation médico-économique de la STImulation MEdullaire mulTi-colonnes (ESTIMET) is a multicentre, randomized study designed to compare the clinical efficacy and health economics aspects of mono- vs. multicolumn SCS lead programming in FBSS patients with radicular pain and significant back pain.

MATERIALS AND METHODS

FBSS patients with a radicular pain VAS score≥50mm, associated with a significant back pain component were recruited in 14 centres in France and implanted with multicolumn SCS. Before the lead implantation procedure, they were 1:1 randomized to monocolumn SCS (group 1) or multicolumn SCS (group 2). Programming was performed using only one column for group 1 and full use of the 3 columns for group 2. Outcome assessment was performed at baseline (pre-implantation), and 1, 3, 6 and 12months post-implantation. The primary outcome measure was a reduction of the severity of low back pain (bVAS reduction≥50%) at the 6-month visit. Additional outcome measures were changes in global pain, leg pain, paraesthesia coverage mapping, functional capacities, quality of life, neuropsychological aspects, patient satisfaction and healthcare resource consumption.

TRIAL STATUS

Trial recruitment started in May 2012. As of September 2013, all 14 study centres have been initiated and 112/115 patients have been enrolled. Preliminary results are expected to be published in 2015.

TRIAL REGISTRATION

Clinical trial registration information-URL: www.clinicaltrials.gov. Unique identifier NCT01628237.

"MAST" prospective study: value of minimal access spine technologies technique for multicolumn spinal cord stimulation surgical lead implantation in the context of a French multicentre randomized controlled trial (ESTIMET study)

BACKGROUND AND PURPOSE

Spinal cord stimulation (SCS) has been demonstrated to be an effective treatment for postoperative persistent leg pain after spine surgery, but treatment of the back pain component remains much more difficult, as it comprises mixed neuropathic and mechanical pain mechanisms. Moreover, these patients could present damaged tissues at the site of SCS lead implantation as a result of previous spine surgery. It can therefore be logically assumed that minimizing the surgical invasiveness of SCS implantation would be beneficial for these patients. Several studies have demonstrated the value of Minimal Access Spine Technologies (MAST) in spine surgery, but only a few case reports have been published concerning the use of MAST techniques for SCS. Therefore, we were prompted to conduct a second ESTIMET ancillary study to prospectively analyse the potential impact and benefits of MAST technique during SCS lead implantation versus an open surgical approach.

METHODS

This is a multicentre, comparative, ancillary study conducted in 61 patients among the 115 enrolled patients ESTIMET study. One arm comprises patients undergoing multicolumn lead implantation via a Conventional Open Approach (COA) and the other arm comprises patients implanted by a MAST approach. Patients will be followed for 12 months after lead implantation. The following data will be collected: elevation of muscle enzymes (serum CPK), scar size, blood loss, infection rate, operating time and global, leg, back and scar NPRS.

TRIAL STATUS

The first patient of this ancillary study was enrolled on 21 May 2012 and recruitment has now been achieved. Primary endpoint findings are expected to be available in 2015.

CONCLUSION

Minimally invasive techniques have now been used for spine surgery for the past 12 years, and could also be useful in the context of SCS lead implantation, especially in patients with chronic back pain prior to implantation.

[Solitary fibrous tumors: Case report of a late relapse]

Authors report a case of a woman with a metastasis of a solitary fibrous tumor, 14 years after the diagnosis of a hemangiopericytoma of the soft tissues. This case report allows discussing the pathological features, the therapeutical option and the outcome of these tumors.

[Systematic review of stereotactic radiotherapy for high-grade gliomas]

The purpose of this literature systematic review was the use of stereotactic radiotherapy in glioma. Research was performed in Medline/PubMed and associated references found in published articles without publication date limit. The quality of series is variable and many biases can be evidenced. Only two randomized trials have been published using stereotactic radiotherapy for up-front treatment. There is a lack of evidence of survival advantages to use this treatment at the time of diagnosis or relapse. There is also insufficient evidence regarding the benefice/harms in the use of stereotactic fractionated radiation therapy for patients with glioma. No recommendations can be enounced. Stereotactic irradiation as boost in primary diagnosed glioma or relapsed tumour is not associated with survival improvement. For relapsed patients, treatment needs to be discussed according to the other treatment options.

[Germ-cell tumors of the central nervous system in childhood: retrospective study of 13 patients]

BACKGROUND AND PURPOSE

Germ cell tumors (GCT) of the central nervous system are rare (2% of all brain tumors in children). Although originating from germ cells, GCT cover a spectrum of different tumors with different management and prognosis, depending on whether they secrete tumor markers or not. The aim of this study is to present a series of children with GCT and comment on overall management practices.

METHODS

We retrospectively reviewed 13 children under the age of 18 years (nine boys and four girls), treated in the same institution between 1986 and 2006 for one or more primitive GCT of the central nervous system.

RESULTS

Median age at diagnosis is 12.9 years (7-17 years). Tumor markers (alpha foetoprotein [alphaFP], human chorionic gonadotrophin [betaHCG]) were assessed 11 times in blood as well as cerebrospinal fluid (CSF). Tumors were located as follows: pineal region (10 cases), hypothalamus (eight cases), basal ganglia (one case) and corpus callosum (one case). Six were bifocal (pineal region and hypothalamus). Clinical signs were mostly dominated by diabetes insipidus and intracranial hypertension. Seven children required surgery for hydrocephalus. Tumor markers were positive in three cases and these children subsequently received chemotherapy followed by radiotherapy, except one child. Eventually, the three patients with positive markers required surgery because of a residual lesion. The eight other patients had a stereotactic biopsy for diagnosis. At the end of follow-up, treatment morbidity appears to be low and neither death nor recurrence was observed. Mean follow-up is 8.85 years (2-20 years).

CONCLUSIONS

The prognosis of cerebral GCTs in children is excellent because of their pronounced chemo- and radiosensitivity. Surgery is crucial for diagnosis in the event of negative markers, or if there is evidence of residual tumor with normalization of tumor markers at the end of chemotherapy. Tumor markers must be monitored to check the diagnosis and for follow-up. The place of tumor biopsy during endoscopic third ventriculostomy (performed if hydrocephalus is present) is still debated.

Germinoma located in the basal ganglia in an 8-year-old girl

CASE REPORT

The authors describe a unique case of an 8-year-old girl with a germinoma located in the left basal ganglia. Medical history begins 5 months before with a central diabetes insipidus, loss of weight (5 kg at admission), vomiting and asthenia. Computed tomography (CT) and cranial magnetic resonance imaging (MRI) are performed and demonstrate a left basal ganglia tumour (nucleus lentiformis). Diabetes insipidus is considered as non-visible germinoma localization on the pituitary stalk rather than as a possible consequence of peri-tumoural oedema surrounding the hypothalamus. Spinal MRI is normal. Neurological as well as general examination is normal.

DISCUSSION

The first hypothesis is low-grade glioma, but pathological examination following a stereotactic biopsy of the lesion reveals a cerebral germinoma. A few days before the biopsy, the girl experienced a mild left facial palsy, and CT scans at the time of biopsy reveals an intra-tumoural haemorrhage. Alpha fetoprotein and human chorionic gonadotrophin were negative as blood and cerebrospinal fluid markers, whereas placental alkaline phosphatase was positive on immunohistochemical profile of the tumour samples. Dedicated chemotherapy, followed by focal irradiation (40 Gy, 30 sessions, 45 days; SIOP CNS GCT 93 protocol), is performed with a complete response. The outcome is good (Glasgow Outcome Scale=I), without any cognitive impairment and the persistence of a mild facial palsy and a slight right arm dystonia on last neurological examination. There is still no evidence of tumour recurrence.

[A prospective study of mycoplasma infection in a neonatal unit]

Ureaplasma urealyticum and Mycoplasma hominis were recovered from nasopharyngeal aspirates from 25% of 63 infants admitted to a neonatal unit; this proportion is significantly higher than that seen in a control population of maternity ward babies (0%). Birth by cesarean section was associated with a reduced risk of recovery of mycoplasmas. No specific diseases were significantly associated with recovery of mycoplasmas; furthermore, no obstetrical factors were associated with recovery of mycoplasmas from the neonates and no association was found between mycoplasma infection and respiratory distress. However, fetal distress, probably of multifactorial origin, was found in 44% of neonates with positive cultures for Ureaplasma urealyticum; this proportion was significantly elevated as compared with the subgroup of infants negative for U. urealyticum, suggesting that fetal distress may increase the infectivity of this opportunistic organism.

[Cerebral arteriovenous malformations in a probable familial form of Rendu-Osler disease]

Cerebral arteriovenous malformations with neonatal manifestations are infrequent and virtually always fatal. Heart failure with an intracranial bruit is the most common presentation. Exceptionally, the aneurysm is a manifestation of Rendu-Osler-Weber syndrome which is inherited on an autosomal dominant basis. Development of cerebral arteriovenous malformations occurs very early as demonstrated by the discovery of two aneurysms with major repercussions on the cerebral parenchyma in a female with severe prematurity. Pregnant women with suspected Rendu-Osler-Weber syndrome should undergo ultrasound studies targeted at identifying untreatable cerebral lesions antenatally.

Clinical and laboratory features of type 1 diabetic children at the time of diagnosis

The French incidence study has registered all new cases of Type 1 diabetic children under 20 years of age, from a population of 2.32 million, in an exhaustive and prospective manner. Three hundred and forty cases were identified between 1 January 1988 and 31 December 1989, yielding a mean annual incidence rate 7.3 per 10(5). The lowest rate was observed in the youngest age group (0-4 yr: 4.1 per 10(5)) and the highest around pubertal development (10-14 yr: 11.5 per 10(5)). Details of the previous personal and family history, and the clinical and biological pictures of the disease at diagnosis were recorded. Almost 8 per cent of the children had a first-degree relative with Type 1 diabetes. Polyuria, weight loss, fatigue and abdominal pain were the most frequently reported symptoms, which were of median duration 4.4 months. Mean weight loss before diagnosis was 9.4 +/- 6.8 (+/- SD)% of body weight and was not significantly related to age. Ketonuria was detected in 83.8 per cent and acidosis (total CO2 less than or equal to 18 mmol l-1, if measured) in 48 per cent of the cases. Ketonuria and acidosis were significantly more frequent in the younger age group than in the rest of the group (p less than 0.001).

A cross-sectional study of plasma and urinary aluminum levels in term and preterm infants

High aluminum levels have been reported in sick and intravenously fed premature infants; however, aluminum is a ubiquitous pollutant of food. This study compares the usual aluminum levels of healthy newborns from birth to the third month of life with those of enterally fed premature infants free of renal failure. Plasma and urine concentrations were determined 66 times in full-term newborns (n = 58), 56 times in a group of preterm infants whose gestational age at birth was 28 to 32 weeks (n = 36) and 54 times in another group of preterm infants whose gestational age at birth was 33 to 36 weeks (n = 50). Daily aluminum intakes (+/- SE) of the full-term infants and the two groups of preterm infants were 0.42 +/- 0.05, 0.64 +/- 0.03, and 0.52 +/- 0.03 mumol/kg per day, respectively (p = .05). Plasma aluminum levels were 0.29 +/- 0.05, 0.49 +/- 0.06, and 0.39 +/- 0.05 mumol/L (p = .007); urine excretion levels were 0.80 +/- 0.12, 0.77 +/- 0.21, and 0.78 +/- 0.2 mumol of aluminum/mmol of creatinine (p value not significant). Although the metabolic consequences of the high aluminum intakes and blood levels we have observed in very low birth weight infants remain to be assessed, these results suggest that more attention should be paid to the aluminum status and intake of healthy premature babies.

Chromium status of full-term and preterm newborns

In order to obtain reference values from normal babies, Cr status of full-term newborns has been studied. Plasma and urine values were (mean +/- SEM) 0.7 +/- 0.1 micrograms/L and 0.9 +/- 0.3 micrograms/L, respectively, for the first month of life (n = 19), and 0.6 +/- 0.1 micrograms/L and 0.8 +/- 0.2 micrograms/L for the second-to-third-month period (n = 31). Premature newborns (gestational age 28-36 wk) were compared to these control values; concentrations were 0.9 +/- 0.1 micrograms/L and 1.1 +/- 0.2 micrograms/L for the first month (n = 47), and 1.0 +/- 0.2 micrograms/L and 1.5 +/- 0.3 micrograms/L for the second to third months (n = 27). For the whole group, there was a positive correlation between plasma and urine concentrations (p = 0.0001); multiple regression analysis was performed between plasma levels and gestational age at birth (p = -0.002) and postnatal age (NS). Plasma levels of prematures and full terms were statistically different (p = 0.03) only for the second- to third-month period. It is suggested that these high Cr levels result from high dietary intakes and/or high absorption rates.

Plasma chromium concentrations in normal infants and cystic fibrosis patients

Plasma Cr concentrations have been studied in normal children aged 0-14 yr. Levels ranged from 0.65 to 0.88 microgram/l and did not change with age. Plasma concentrations of CF patients given 0.5-0.75 microgram Cr/kg/d in addition to their diet were similar to normal values. There was no correlation between these plasma values and growth retardation.

Molybdenum in the premature infant

The molybdenum (Mo) levels in the plasma and urine of 30 premature and 15 full-term infants have been compared with the Mo intakes and urine uric acid excretion (uric acid/creatinine ratio) produced by the Mo enzyme xanthine oxidase. The Mo intakes of full-term infants were 41 +/- 14 nmol/kg/day (mean +/- SEM). In the premature group breast milk supplied significantly less Mo (4.3 +/- 0.4 nmol/kg/day) than infant formulas (101 +/- 31 nmol/kg/day) or premature formula (255 +/- 13 nmol/kg/day). When fed breast milk, the preterm infants displayed similar or higher plasma and urine Mo and urine uric acid levels than formula-fed infants. For the whole preterm group a significant correlation was determined for urine Mo levels and Mo intakes as well as for plasma Mo and uric acid excretion. The bioavailability of breast milk Mo seems to be higher than formula Mo according to the Mo levels and to their statistical link with uric acid excretion which could be proposed as a functional index of Mo status. These parameters displayed similar values in breast milk-fed prematures and control full-term infants. The Mo needs of formula-fed premature newborns remain to be defined using complete balance trials.

[Moebius syndrome with pharyngo-laryngeal paralysis in a premature infant]

A case of Moebius syndrome in a premature baby is reported. After a phase of neonatal severe respiratory distress syndrome, the baby presented with a persistent facial paralysis, already present at birth and inability to close the eyes (also present in her father), without ophthalmoplegia. An unusual pharyngeal and laryngeal paralysis was also present: it led to tracheal intubation then tracheostomy and gastrostomy. CT scan at 15 months of age showed hypoplasia of brain stem. The difficulties of managing bulbar paralysis in such a premature baby are emphasized.

Incidence of juvenile type 1 (insulin-dependent) diabetes mellitus in France

The incidence rate of juvenile Type 1 (insulin-dependent) diabetes in France was reported as the lowest in Europe 13 years ago, but during the recent years increasing rates have been observed in different European countries. A prospective programme has been designed to study the incidence rate of Type 1 diabetes in patients up to 20 years of age in four regions located in the north and south of France (population less than 20 years = 2.31 million inhabitants; 15% of the French population). All cases were independently identified by four specially trained research assistants through hospital admission files, paediatricians, diabetologists and general practitioners. A specific questionnaire was filled out for each newly diagnosed case. Degree of ascertainment was 96% with the data from Sécurité Sociale, the French National Health Insurance. In 1988, 166 cases of juvenile Type 1 diabetes were identified. The incidence rate was 7.17 cases per 10(5) children (95% confidence interval = 6.1-8.2/10(5). The values were not statistically different among the four regions. Age specific incidence rates were as follows: 0-4 years = 3.8; 5-9 years = 8.0; 10-14 years = 9.7 and 15-19 years = 7.3/10(5). Sex ratio was 1.2 (male/female). These data indicate that incidence of juvenile Type 1 diabetes in France was higher in 1988 than previously reported but remains lower than in Northern Europe. This is consistent with the concept of a north to south gradient of the disease.

[Neonatal nemaline myopathy with favorable outcome]

A case of neonatal nemaline myopathy without respiratory distress is reported in a neonate. Its relatively benign course allowed survival without major complications. The discovery of a "central core disease" myopathy in her asymptomatic father confirms the relation between both entities.

Maturation of peripheral nerves in preterm infants. Motor and proprioceptive nerve conduction

The peripheral nerve maturation (proprioceptive and motor nerve conduction velocities (PNCV and MNCV] was studied in 3 groups of newborn babies. Two groups of premature babies (PT), studied when they reached the expected date of birth (group I, gestational age (GA) at birth 27-31 weeks, n = 13, group II, GA at birth 32-35 weeks, n = 9), were compared to 10 normal full-term newborns (FT). The MNCV of PT babies was similar to that of FT babies: group I 22.8 +/- 3.3 m/sec (X +/- S.D.), group II 24.9 +/- 4.3 m/sec, FT 25.7 +/- 3.9 m/sec. PNCV was significantly lower in group I (18.1 +/- 5.9 m/sec) than in group II (28.3 +/- 6.4 m/sec) and in FT babies (32.0 +/- 7.4 m/sec) (P less than 0.001). Such a delay in maturation could be partly responsible for the neurological impairment often observed in PT babies.