Hyperkinetic Movement Disorders in Children- A Brief Review

Ali Nikkhah, Parvaneh Karimzadeh, Mohammad Mahdi Taghdiri, Mohammad Mahdi Nasehi, Mohsen Javadzadeh, Elaheh Khari

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 7-16

Movement disorders are common neurologic disturbances in childhood. There are two major types movement disorders. Hypokinetic disorders are with paucity of voluntary movements and are very uncommon in pediatric age group. Hyperkinetic movement abnormalities are very common in children and defined as abnormal repetitive involuntary movements. Movement disorders in childhood and even in adolescents are different in etiology, timing, treatment and prognosis versus adulthood movement abnormalities. In this brief article, we reviewed common types of hyperkinetic abnormal movements in children and adolescents with emphasis on etiologies, new classifications and recent treatment strategies.      

A Novel Intervention Technology for Cerebral Palsy: Brain Stimulation

Sara Ramezani, Naser Amini, Fatemeh khodaei, Hosein Safakheil, Arash sarveazad, Lena Mohebi, Peiman Brouki milan

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 17-28


A common pediatric disorder with posture and motor dysfunction

in neurological diseases is known as cerebral palsy (CP). Recently,

a series of effective techniques have been developed for treatment

of CP. These promising methods need high-tech equipment for

brain stimulation and mainly classified into invasive and noinvasive

approaches. This study aimed to introduce these techniques

for treatment of patients who suffer from CP. The potential and

performance of currently available brain stimulation techniques have

been mentioned in detail. Moreover, the clinical application, safety,

efficacy and challenges of these methods have been discussed. Here

we review the recent advances in the CP treatment with an emphasis

on brain stimulation techniques


Cerebral palsy; Brain stimulation; Pediatric disorder

A preliminary survey of Autism knowledge and attitude among health care workers and pediatricians in Tehran, Iran

Mohammad Effatpanah, Ghazal Shariatpanahi, Amirsina Sharifi, Rozita Ramaghi, Reza Tavakolizadeh

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 29-35

Objective: Autism spectrum disease (ASD) is not a common diagnosis for children presenting with neurodevelopmental delay before 36months in Iran. Although recent years have witnessed improvements in diagnosis of pediatrics psychological disorders but the role of referral system starting with health care workers (HCW) is not clear.

Methods: Pediatricians were randomly selected from four teaching hospital of Tehran University of Medical Sciences Iran. HCW were randomly selected from 3 urban health care centers in Tehran, Iran. DSM-IV TR criteria for ASD was used to assess knowledge. Participants were asked to rate sixteen statements on beliefs about autism to assess attitude.

Results: one hundred and twenty two pediatricians and ninety HCWs with mean ± SD age of 36±4.7   years and 76.4% being female recruited. Pediatricians had significantly higher encounter with autistic patients (18% Vs 10%, p value=0.06) and parents of autistic child (17% Vs 12%, p value=0.07). But generally 209 participants (98.6%) declared that they are familiar with autism. There was no statistically significant difference between study groups in rating DSM-IV TR criteria for ASD as “necessary for diagnosis”. Age, gender and working experience, did not differ pediatricians or HCW answers (all p values > 0.05). Among HCW participants, higher educational level was associated with higher disagreement about “autistic children is schizophrenic”(p value=0.01). Also HCW with higher working experience had higher agreement rate with “autistic children needs special education” statement (p value= 0.04).

Conclusion: There are still misconceptions about ASD regarding developmental, cognitive and emotional features in both HCW and pediatricians needed to be educated through national program.  

Short-term side effects of low dose valproate monotherapy in epileptic children: a prospective study

Parisa Nasr Esfahani, Jafar Nasiri, Shervin Badihian, Omid Yaghini

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 37-46

Objectives: Considering the common use of valproate among children, we investigated short-term side-effects of low dose valproate monotherapy in epileptic children.

Materials and Methods: In this prospective study, 209 epileptic children (48.3% male, mean age: 7.02 ± 3.13 years) on low therapeutic dose of valproate monotherapy (20-30 mg/Kg/daily) were enrolled and side-effects were evaluated through frequent clinical visits and laboratory tests during 6 months.

Results: Weight gain was reported in 53.1% of patients. Decreased appetite was seen in 11% of patients, more frequent in younger cases (P=0.006). Abdominal pain, nausea/vomiting, diarrhea, and constipation were reported in 16.3%, 2.4%, 1.4%, and 1% of patients, respectively. Headache, tremor, dizziness, abnormal color vision, myoclonus, and bruxism were seen in 5.7%, 1.4%, 1%, 1%, 1%, and 0.5% of patients, respectively. Enuresis, hair loss, and skin rash were reported in 8.1%, 6.7%, and 0.5% of patients, respectively. Thrombocytopenia, impaired liver function tests, and leukopenia occurred in 1%, 1%, and 0.5% of patients, respectively.

Conclusions: low dose valproate monotherapy may cause numerous side-effects, mostly not life-threatening and requiring no action. Besides more reported complications, we observed decreased appetite (among younger patients), enuresis, and abnormal color vision which have been briefly discussed in the literature and need to be addressed more.

Gastroenteritis Related Seizure with or without Fever: Comparison Clinical Features and Serum Sodium Level

Farhad Heydarian, Elham Bakhtiari, Shima Badzaee, Mohammad Heidarian

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 47-52

Objective: To investigate the clinical characteristics and serum sodium level in children with gastroenteritis related seizure with or without fever.

Methods: 165 patients aged 6-60 months with gastroenteritis related seizure were studied. Demographic, seizure and gastroenteritis characteristics and laboratory findings were recorded.

Results: Among the 165 children 47.3% were female and 52.7% were. Vomiting was 2.7±2.6 and 3.9±1.9 times in febrile and afebrile group. Duration of diarrhea was 1.8±1.8 day and 2.1±1.3 day in febrile and afebrile group (p=0.014). 36% in febrile group and 6.4% in afebrile group experienced seizure within the first 24 hours of gastroenteritis (p<0.001). Seizure in 99.1% in febrile and 93.6% in afebrile group was generalized (p>0.05). Seizure was more than 5 minutes in 51.4% in febrile and 57.4% in afebrile group (p>0.05). Drowsiness after seizure was seen in 72.9% and 60% in febrile and afebrile group (p>0.05). The serum level of sodium was 137.6±3.98 mEq/L and 138.5±3.78 mEq/L in febrile and afebrile group (p>0.05). 26.3% in febrile group and 8.5% in afebrile group had hyponatremia (p=0.012). There was no difference in seizure duration between hyponatremic patients and others (p>0.05).

Conclusion: Type, duration of seizure and drowsiness after seizure had not any difference in febrile and afebrile cases. Vomiting and duration of diarrhea before admission was lower in febrile group. Seizure within the first 24 of gastroenteritis was higher in febrile group. Mild hyponatremia in febrile group was higher than afebrile group. No difference in duration of seizure was detected between hyponatremic patients and others.

Effects of empowerment program on the burden of care in mothers of children with phenylketonuria

Abolfazl Rahgoi, Tahere Sojoodi, Masoud Fallahi Khoshknab, Mehdi Rahgozar, Soheila Shahshahani

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 53-60

Objectives: Phenylketonuria (PKU) is a genetic disease of children that need a lifelong diet for its treatment. Because of the high burden of care, Parents and particularly mothers are prone to mental disorders or psychiatric adverse reactions. This study aimed to investigate the effect of empowerment of mothers on the burden of caring children with phenylketonuria.

Materials & Methods: This was a semi-experimental (before-after with control group) study. In this research, 50 mothers of children with phenylketonuria that were referred to endocrine clinic in Qods hospital of Qazvin city, were selected and randomly divided into intervention and control groups. Data collection was made by using demographic characteristics of mothers and children and also the Zarit burden interview questionnaires. Empowerment program was delivered during nine sessions of holistic and family oriented empowerment model in the intervention group.  The control group received routine services. Data were analyzed using descriptive and inferential statistics through SPSS software version 18.

Results: In intervention group, the mean score of overall care burden and its dimensions in the mothers of children with phenylketonuria in post-test was significantly lower than the pre-test  (41.20 ± 5.04 vs. 58.24 ± 3.96; p<0. 001); but  pre-test and post-test scores in the control group had no significant difference (58.4 ± 5.22 vs. 58.96 ± 4; p=0.327). In other words empowerment program was able to reduce the burden of caring in mothers.

Conclusion: Empowerment program can reduce the burden of care in mothers of children with phenylketonuria. Thus it seems that empowerment training is necessary to this group of mothers in the form of workshops and educational pamphlets.

The Impact of Home Motor Affordances on Motor, Cognitive and Social Development of Young Children

Asiye Zoghi, Carl Gabbard, Masoumeh Shojaei, Soheila Shahshahani

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 61-69

The present study evaluated the influence of home motor affordances on motor, cognitive, and social development of young children. The sample consisted of 49 Iranian children, ages 24-42 months. The sample was randomly selected by multi-stage cluster sampling from a single community. Participant’s homes were assessed using the Affordances in the Home Environment for Motor Development (AHEMD). The motor behavior of young child was measured with the Denver Developmental Screening Test, aspects of cognitive development (Total cognitive, Verbal IQ, and non-verbal IQ) were assessed using the Stanford-Binet scale, and finally, social development was measured by the Vineland Adaptive Behavior Scale. Although no statistically significant correlations were found between Total AHEMD scores and motor development, there were significant and positive correlations for Total AHEMD with total cognitive development (.29), verbal IQ (.29), social development (.33), and socioeconomic status (SES) (.51). Also there was a significant relationship between the Play Materials subscale of the AHEMD with total cognitive development (.32), verbal IQ (.31), and social development (.35). In addition, there were significant differences between Total AHEMD score with parents who had an academic education. Our results suggest that motor affordances in the home can have a significant positive influence on a young child’s cognitive and social development.

Ictal Electroencephalographic Findings in Children with Migraine Headache

Hamed Shafagh, MohammadKazem Bakhshandeh Bali, Esfandiar Matini, Marjan Mohammadnuri, Seyedeh Mohadeseh Taheri Otaghsara, Aria Baktash

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 71-75

Background: In this study the EEG findings in children with migraine headache were assessed in Bahrami Hospital since 2014 to 2016.

Methods and materials: In this observational cross-sectional study, 71 consecutive children with migraine headache were assessed in Bahrami Hospital since 2014 to 2016. The EEG findings in them were determined and compared according to other variables.

Results: There were 25 cases (35.2 percent) with abnormal EEG which the type of  EEG abnormality comprised slow waves and  sharp waves in 19(68%) and 8(32%) patients respectively

Conclusion: Totally, according to the obtained results, it may be concluded that nearly one-third of children with migraine may have abnormal EEG.

Key words: EEG, Children, Migraine

The relationship between severity of epilepsy and sleep disorder in epileptic children

Maryam Dehghani, Afshin Fayyazi, Fatemeh Cheraghi, Hamideh Hakimi, Somayeh Mosazadeh, Saeideh Almasi

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 77-88

Background: Sleep disturbances are one of the most common behavioral problems in childhood. Sleep problems have an even greater prevalence in children with epilepsy and are one of the most common comorbid conditions in childhood epilepsy.

Methods: The present study was a descriptive- correlation study with the general goal of determining the effects of epilepsy on sleep habits of epileptic children in Hamadan, Iran, in 2014. Sampling was done using convenience sampling techniques. Data was collected by using The Early Childhood Epilepsy Severity Scale (E-Chess) and Children’s Sleep Habits Questionnaire (CSHQ). It was analyzed by using SPSS (20) and descriptive and inferential statistics.

Results: The mean score of sleep habits were 55/08 ± 6/71. Bedtime resistance (12/14 ± 2/93), parasomnias (11/02 ± 1/84) and sleep anxiety (8/29 ± 2/46) were the most frequent sleep disorders in the studied sample. Based on Pearson’s r, there were significant positive bidirectional relationships between bedtime resistance (rs = 0.129, p < 0.019), parasomnias (rs = 0.298, p < 0.005), sleep disordered breathing (rs = 0.295, p < 0.005), CSHQ total score (rs = 0.144, p < 0.022) on the one hand, and children’s epilepsy severity on the other.

Conclusion: Sleep problems should not be overlooked, and a comprehensive review of the sleep habits of this group of patients should be conducted.


The Efficacy of Phonological Processing Treatments on Stuttering Severity in Persian Pre-school Children

Neda Tahmasebi, Mohadeseh Rasti borujeni, Majid Soltani, Mahmood Latifi, Negin Moradi

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 89-102


Objectives: Correct phonological encoding is crucial to fluent speech production. Phonological working memory and phonological awareness are important phonological processes that affect phonological encoding. Studies have shown weakness in phonological encoding in people who stutter. The purpose of this study was to investigate the effect of phonological processing on stuttering severity of Persian pre-school children.

Method: Six children who stutter participated in a 13-session treatment protocol. The treatment protocol of the phonological processing included nonword repetition in the phonological working memory and phonological awareness therapy. Stuttering severity measurement was performed pre- and post-treatment.

Results: Stuttering severity score was compared in pre- and post-treatment, and in the follow-up phase; that showed stuttering severity was reduced in children who stutter. Moreover, severity rating, reported by parents during treatment, showed a reduction in stuttering severity. 

Conclusion: The poor performance of phonological awareness and phonological working memory in phonological processing affect stuttering severity. The outcomes of this study showed that treatment of sub-systems of phonological processing can play a role in reducing stuttering severity.


Top-down auditory plasticity: Acceptable noise level predicts and reflects the effect of perceptual learning in experience-induced plasticity

Hamid Jalilvand, Elahe Ravanshenas, Alireza Akbarzade Baghban

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 103-111

Objective: In the auditory system, tinnitus and superior speech perception in noise are examples of negative and positive plasticity that can result from sensory neural hearing loss and life experiences dealing with more complex stimuli and learning, respectively. Positive plasticity occurs as a result of learned skills and sensory stimuli; plasticity involves specific neural pathways and can be observed in auditory ascending or descending pathways.

Materials & Methods: In this study, we document a form of plasticity in top-down auditory pathways through the measurement of acceptable noise level in 60 adults (27 females and 33 males) with normal hearing. Individuals were assigned to one of two groups: those with and without occupational experience of speech perception in noise.

Result: The results showed that the test group had statistically significant lower acceptable noise level and significantly higher background noise level scores compared with the control group.

Conclusion: Using acceptable noise level, we attributed differences in individuals’ abilities to tolerate varying amounts of background noise and speech perception in noise function to the auditory efferent system. We therefore concluded that working in crowded locations due to job nature can influence differences in speech perception in noise function.

The development of an interventional package on "receptive vocabulary” for cochlear implanted children

Leila Monshizadeh, Roshanak Vameghi, Firoozeh Sajedi, Fariba Yadegari, Mehdi Rahimi, Seyed basir Hashemi

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 113-123


Due to the shortage of language intervention protocols which specifically concentrate on language acquisition in cochlear implanted children and considering the importance of timely language intervention programs in this group of children, the aim of the present study was to develop an interventional package on “receptive vocabulary” based on the process of vocabulary development in normal children.  

Materials and Methods:

By reviewing the literature related to language acquisition theories in normal and language disordered children, as well as literature on production of intervention protocols, especially those for language impaired children, and also considering the normal process of language and speech development in normal children, the first draft of the intervention protocol was prepared. Then, with the collaboration of 10 expert pediatricians, speech and language pathologists and linguistic experts as members of a Delphi team, the face and content validity of the intervention protocol was assessed through three Delphi rounds and finally approved.


A step by step language intervention protocol entitled “An educational package on receptive vocabulary development of 12-48 months old Persian speaking cochlear implanted children “was developed based on developmental, cognitive and behavioral models and the normal process of language and speech development in children.


The interventional package produced is believed to facilitate language acquisition in cochlear implanted children, according to expert qualitative assessment and approval. However, experimental research is required for verification of this assumption.

Protein interaction mapping related to Becker Muscular Dystrophy

Ali Azghar Peyvandi, Farshad Okhovatian, Majid Rezaei-Tavirani, Mona Zamanian-Azodi, Mostafa Rezaei-Tavirani

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 125-134


Becker Muscular Dystrophy (BMD) is a neuromuscular disorder which is incurable. In this research protein interaction network of most associated proteins with Becker muscular dystrophy to provide a better clarification of disorder underlying mechanism is investigated.

Materials & Methods

 The related genes to BMD were retrieved via string data base and conducted by Cytoscape and the related algorithms. The network centrality analysis was performed based on degree, betweennes, closeness and stress parameters. Gene ontology and clustering were performed via ClueGO analysis.


The results indicate that DMD as the super-hub as well as other central proteins including UTRN, TTN, DNM2 and RYR1 are important in BMD in terms of interaction features. The impairment of muscular contraction may be vital in BMD disease pathogenesis as it is the highlighted biological process term obtained by ClueGO analysis.


It is possible that DMD targeting may be the main concern for dystrophy clinical approaches. However the other suggested proteins should be evaluated.


 In conclusion, targeting these key proteins are required for treatment goals following extensive validation studies.

No Hot Spot Mutations CHRNE c.1327 delG, CHAT c.914T>C, and RAPSN c.264C>A in Iranian Patients with Congenital Myasthenic Syndrome

Sima Parvizi Omran, Massoud Houshmand, Dominic Donkor, Zahra Farjami, Parvaneh Karimzadeh

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 135-143



We aimed to perform genetic testing and clinical data of patients with Congenital Myasthenic Syndrome, a rare disorder caused by mutations in genes encoding molecules expressed in the neuromuscular junction and constitutes fatigable muscle weakness.



Sixteen patients were screened in Taban Clinic, Tehran, Iran from 2014 to 2015 for the hot spot mutations in known CMSs genes (CHRNE, CHAT, RAPSN) based on clinical data. PCR was performed and then direct DNA sequencing was done for mutation identification.


Most patients represented the criteria of Congenital Myasthenic Syndrome in view of early ptosis, motor delay, normal mental development, easy fatigability, decrement in repetitive nerve stimulation test of EMG-NCV and a negative result for antibody against of acetylcholine receptor. No variations were found in the mutational analysis of the CHRNE gene. Analysis of CHAT gene revealed c.358G>A (P. A120T) variation in 9 patients. In the gene RAPSN, polymorphism c.456T>C )P.Y152Y) and polymorphism c.193-15C>T (IVS1-15C>T) were identified in 11 and one patients, respectively.


The common founder mutations of involved genes in CMSs could be very rare among ethnic Iranian. Screening of the entire genes would be efficient to distinguish the specific mutations in specific ethnicity.

Developmental screening of children with congenital hypothyroidism using Ages & Stages Questionnaires test.

Zahra Razavi, Setila Dalili, Mohammad Kazem Sabzehei, Arman Yousefi, Shahla Nouri, Mahbubeh Abedi, Hassan Bazmamoun

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 145-154


Objectives: Congenital hypothyroidism (CH) is one of the most common causes of mental retardation in children. This study investigated the developmental status of children with CH screened by Ages & Stages Questionnaires (ASQ) measurement scores.

Materials & Methods: In this retrospective study, neurodevelopmental status of 78 children diagnosed with CH who being followed up at the outpatient Pediatric Endocrinology Clinic of Besat Hospital, Hamadan, Iran, was evaluated by ASQ method. Data on age, sex, birth body weight, height and head circumference, residency location, parental education level, primary venous TSH and T4 level, diagnosis age, treatment start age and initial levothyroxine dosage were extracted from medical records .Data analyzed using statistical software SPSS v16. P-value less than 0.05 was considered statistically significant.

Results: Of the 78 patients (34=43.6% female), 32 patients (41%) had developmental disorder. 56 cases (71.8%) were living in urban areas. In terms of type of developmental impairment, global delay: 13 patients (40.6%), problem solving: 11 patients (34.3%), communication: 5 patients (15.6%), fine motor: 2 patients (6.2%) and personal-social: 1 patient (3.1%) were detected. The average of diagnosis and treatment age was 25.65 days in patients with developmental impairment and 17.99 days in those without delay. ASQ results had significant statistical correlation with initial dose of levothyroxine (p=0.017), hypothyroidism diagnosis age (p=0.002) and age of treatment initiation (p=0.018).

Conclusions: Early diagnosis and treatment along with initial L-thyroxin dose were most important factor of ASQ scores of children with CH. Higher amounts of the LT4 is required at onset.

Niemann-Pick Diseases; largest Iranian cohort with genetic analysis

Somayyeh Hashemian, Peyman Eshraghi, Nafi Dilaver, Hamid Galehdari, Bita Shalbafan, Rahim Vakili, Nosrat Ghaemi, Najmeh Ahangari, Jamileh Rezazadeh Varaghchi, Jawaher Zeighami, Alireza Sedaghat, Majid Aminzadeh, Mohammad Hamid, Alihossein Saberi, Fereshteh Ashtari, Ehsan Ghayoor Karimiani, Gholamreza Shariati

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 155-162

Background: Niemann-Pick diseases (NPD) is an autosomal recessive inherited lysosomal lipid storage disorder which occurs due to a defect in cellular cholesterol trafficking, leading to excess lipid accumulation in multiple organ systems such as the brain, lungs, spleen and liver. SPMD1-associated disease includes classic infantile and visceral NPD type A and B respectively. Type C NPD is subacute or juvenile.

Methods: Sanger sequencing of the candidate genes for NPD were performed followed by bioinformatic analysis to confirm the types of NPD and to identify novel mutations. All patients underwent full clinical assessment.

Results: In this case series, we present two cases with NPD type A, six cases with NPD type B, and 11 cases with type C with various enzymatic defects identified in these cases. Within these 19 patients we present seven previously reported mutations and 10 novel mutations causing NPD.

Conclusion: Our report demonstrates that NPD has a variable age of onset and can present early in life. In this study, we investigated the clinical and genetic manifestations of a large Iranian cohort. Understanding the variable presentation of NPD will allow for clinicians to have a high index of suspicion for the disease.

Hemangioblastoma of the Central Nervous System: A Case Series of Patients Surgically Treated at

Mahsa Ahadi, Hanieh Zham, Azadeh Rakhshan, Mitra Rafizadeh, Davood Talebi Bayazi, Masoud Baikpour, Afshin Moradi

Iranian Journal of Child Neurology, Vol. 13 No. 2 (2019), 4 March 2019 , Page 163-169

Objective: Hemangioblastoma refers to a benign vascular neoplasm that comprises stromal and capillary cells. Based on the classification of nervous system tumors proposed by the World Health Organization, hemangioblastomas are classified as Grade I meningeal tumors of uncertain origin. These tumors are found almost exclusively in the central nervous system (CNS) and account for 0.9 to 2.1% of all primary CNS tumors.

Methods: In this descriptive retrospective study, the archives of pathology reports were reviewed in the department of pathology of Shohadaye Tajrish Hospital and patients with definite diagnosis of hemangioblastoma made through histpopathological examinations during 2004-2014 were identified. Age, gender and the location of tumor were extracted from the medical records and entered into SPSS statistical software v.22 for analysis.

Results: A total of 30 patients including 16 males (53.3%) and 14 females (46.7%) were identified. The mean age of the patients was calculated to be 41.2±13.47 years, ranging from 19 to 62 years old. The majority of lesions had been found in the cerebellum of the patients (93.3%); only one had occurred in the cerebrum (3.3%) and another in the fourth ventricle (3.3%). 

Conclusion: Cerebellum is the most commonly affected location in patients with CNS hemangioblastomas, and a male preponderance is observed in these cases.