[Hypothalamic hamartoma dissection using focused ultrasound under MRI control. The first successful experience in Russia]

Treatment of motor disorders by MRI-guided focused ultrasound is an alternative to neuro- and radiosurgery such as stereotactic radiofrequency ablation and thalamotomy with a gamma knife. However, safety, efficacy and feasibility of this technology for intracranial neoplasms are still unclear. The authors report successful hypothalamic hamartoma dissection by MRI-guided focused ultrasound in a 32-year-old woman with drug-resistant gelastic epilepsy and violent laughter and crying attacks. Magnetic resonance imaging revealed type II hypothalamic hamartoma. The last one was detached from surrounding brain tissue by MRI-guided focused ultrasound without side effects. Symptoms regressed immediately after surgery. No laughter and crying attacks were observed throughout 6-month follow-up.

Seizure outcomes and safety profiles of surgical options for epilepsy associated to hypothalamic hamartomas. A systematic review and meta-analysis

PURPOSE

Several surgical options are available for treating hypothalamic hamartoma-related epilepsy but their respective efficacy and safety profiles are poorly defined.

METHODS

A literature search identified English-language articles reporting series of patients (minimum 3 patients with a follow-up ≥12 months) operated on by either microsurgery, endoscopic surgery, radiosurgery, radiofrequency thermocoagulation or laser interstitial thermal therapy for hypothalamic hamartoma-related epilepsy. The unit of analysis was each selected study. Pooled rates of seizure freedom and of neurological and endocrinological complications were analyzed using meta-analysis to calculate both fixed and random effects. The results of meta-analyses were compared.

RESULTS

Thirty-nine studies were included. There were 568 and 514 participants for seizure outcome and complication analyses, respectively. The pairwise comparison showed that: i) the proportion of seizure-free cases was significantly lower for radiosurgery as compared to microsurgery, radiofrequency thermocoagulation and laser ablation, and significantly lower for endoscopic surgery as compared to radiofrequency thermocoagulation; ii) the proportion of permanent hypothalamic dysfunction was significantly higher for microsurgery as compared to all other techniques, and significantly lower for endoscopic surgery as compared to radiofrequency thermocoagulation and laser ablation; iii) the incidence of permanent neurological disorders was significantly higher for microsurgery as compared to endoscopic surgery, radiosurgery and radiofrequency thermocoagulation, and significantly lower for radiosurgery as compared to laser ablation.

CONCLUSIONS

Minimally invasive surgical techniques, including endoscopic surgery, radiofrequency thermocoagulation and laser ablation, represent an acceptable compromise between efficacy and safety in the treatment of hypothalamic hamartoma-related epilepsy. Microsurgery and radiosurgery should be considered in carefully selected cases.

Does subtotal resection ameliorate hypothalamic morbidity in pediatric craniopharyngioma? A 30-year retrospective cohort study

OBJECTIVE

The optimal extent of resection of craniopharyngiomas to minimize the long-term risks of hypothalamic and endocrine dysfunction (obesity and panhypopituitarism) in children remains uncertain. The purpose of this study was to report long-term outcomes of pediatric patients with craniopharyngioma undergoing surgical treatment and to study rates of endocrinological and hypothalamic dysfunction in association with extent of resection.

METHODS

This retrospective study was performed in a cohort of children who underwent resection for craniopharyngioma at Children's of Alabama between 1990 and 2020. The primary outcome was hypothalamic dysfunction defined as a 0.5 increase in body mass index (BMI) Z-score and as a BMI > 2 SDs with or without psychiatric disturbances. Univariable analysis was performed using ANOVA, Wilcoxon rank-sum test, Pearson's chi-square test, and Fisher's exact test as appropriate. Missing data on the primary outcome were handled via multiple imputations. Relative risks were estimated using a multivariable generalized linear model with a priori variables selected using a modified Poisson regression approach with robust error variance to estimate risk ratios.

RESULTS

The cohort includes 39 patients (24 girls and 15 boys; age range 1 month-16 years) who underwent resection of craniopharyngioma at the authors' center between 1990 and 2020. The preoperative goal of treatment was cyst decompression (CD) in 5, subtotal resection (STR) in 13, and gross-total resection (GTR) in 21 patients. The median long-term follow-up after surgery was 8.11 years (average 8.21, range 0.4-24.33 years). Univariate analysis demonstrated a statistically significant increase in hypothalamic dysfunction in patients undergoing GTR when compared to those undergoing STR or CD at 1 month postoperatively (p = 0.006) and 6-11 months postoperatively (p = 0.010), but with this difference not persisting beyond 1 year. Multivariable analysis showed patients older than 10 years at time of surgery to be the most affected and at highest risk of developing significant hypothalamic dysfunction. There was no significant difference in pituitary or neurological function between the STR/CD and GTR groups at 12-24 months or at most recent follow-up. There was no significant difference in BMI Z-scores between the STR/CD and GTR groups at 6-12 months or at most recent follow-up.

CONCLUSIONS

Both STR and GTR of craniopharyngioma were associated with significant endocrinological sequelae after 1 year. These potential complications should be discussed with patients and their families, and postoperative protocols should include early nutritional and endocrinological interventions with endocrinologist consultation.

Epilepsy surgery in patients with hypothalamic hamartomas - Population-based two-year and long-term outcomes

OBJECTIVE

Hypothalamic hamartomas are benign lesions associated with drug resistant epilepsy. Surgical treatment has become an increasingly utilised approach with promising results. This study aims to evaluate seizure outcome and complications after surgery in a population-based series of patients with intractable epilepsy and hypothalamic hamartoma.

METHODS

All patients with hypothalamic hamartoma treated with epilepsy surgery in Sweden since 1995 with at least two years of follow-up were included. Preoperative, two-, five- and ten-year prospective longitudinal data were collected from The Swedish National Epilepsy Surgery Register. Data included seizure types and frequency, duration of epilepsy, clinical characteristics, neurological deficits, cognitive level and complications. In a subgroup from Gothenburg, we also analysed data not included in the register such as classification of hamartomas, surgical procedures and gelastic seizures.

RESULTS

Eighteen patients were operated on during the period 1995-2020. The median age at epilepsy onset was 6 months and age at surgery 13 years. Four were seizure free and another four had ≥75% reduction in seizure frequency at the two-year follow-up. Two of the 13 patients with a long-term follow-up (five or ten years) were seizure-free and four had ≥75% reduction in seizure frequency. Three had an increased seizure frequency. No major complications were seen. Five had minor complications. In the Gothenburg subgroup all had open pterional disconnection or intraventricular endoscopic disconnection. Six of 12 were free from gelastic seizures at the two-year follow-up and six of eight at the long-term follow-up.

CONCLUSION

This study supports surgical treatment of hypothalamic hamartomas as a safe method with a low risk of permanent complications. The seizure reduction seems to be persistent over time.

Long term outcome after surgical treatment for hypothalamic hamartoma

PURPOSE

To determine long-term outcome for seizure control and clinical predictors for seizure freedom in patients undergoing surgical treatment for epilepsy associated with hypothalamic hamartoma (HH).

METHODS

155 patients underwent surgical treatment for HHs and treatment-resistant epilepsy at one center (Barrow Neurological Institute at St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA) between February 2003 and June 2010. Data collection included medical record review and direct follow-up interviews to determine seizure outcome. Statistical analysis included descriptive summaries of patient characteristics and time-to-event analysis for seizure freedom.

RESULTS

Long-term survival with follow-up of at least five years since first surgical treatment was available for 108 patients (69.7% of the treatment cohort). The surgical approach for first HH intervention consisted of transventricular endoscopic resection (n = 57; 52.8%), transcallosal interforniceal resection (n = 35; 32.4%), pterional resection (n = 7; 6.5%), and gamma knife radiosurgery (n = 9; 8.3%). Multiple surgical procedures were required for 39 patients (36.1%). There were 10 known deaths from all causes in the treatment cohort (6.5%). Of these, one (0.6%) was related to immediate complications of HH surgery, three (1.9%) were attributed to Sudden Unexpected Death in Epileptic Persons (SUDEP), and one (0.6%) to complications of status epilepticus. For surviving patients with long-term follow-up, 55 (50.9%) were seizure-free for all seizure types. Univariable analysis showed that seizure-freedom was related to 1) absence of a pre-operative history for central precocious puberty (p = 0.01), and 2) higher percentage of HH lesion disconnection after surgery (p = 0.047). Kaplan-Meier survival analysis shows that long-term seizure outcome following HH surgery is comparable to short-term results.

SUMMARY

These uncontrolled observational results show that long-term seizure control following HH surgical treatment is comparable to other forms of epilepsy surgery. Late relapse (at least one year after surgery) and SUDEP do occur, but in a relatively small number of treated patients. These results inform clinical practice and serve as a comparable benchmark for newer technologies for HH surgery, such as magnetic resonance imaging-guided laser interstitial thermal therapy, where long-term outcome results are not yet available.

Posterior hypothalamic involvement on pre-operative MRI predicts hypothalamic obesity in craniopharyngiomas

PURPOSE

Hypothalamic obesity (HO) is a complication associated with craniopharyngioma (CP). Attempts have been made to perioperatively predict the development of this complication, which can be severe and difficult to treat.

METHODS

Patients who underwent first transsphenoidal surgical resection in a single center between February 2005 and March 2019 were screened; those who have had prior surgery or radiation, were aged below 18 years, or did not have follow up body mass index (BMI) after surgery were excluded. Primary end point was BMI within 2 years post-surgery. Hypothalamic involvement (HI) was graded based on preoperative and postoperative imaging with regards to anterior, posterior, left and right involvement. Data on baseline demographics, pre-operative and post-operative MRI, and endocrine function were collected.

RESULTS

45 patients met the inclusion and exclusion criteria. Most patients in our cohort underwent gross total resection (n = 35 patients). 13 patients were from no HI or anterior HI only group and 22 patients were classified as both anterior (ant) and posterior (post) HI group. There was no significant difference between the two groups in the gross total, subtotal or near total resection. Pre-operative BMI and post-operative BMI were significantly higher in patients who had ant and post HI on pre-operative MRI (p < 0.05 and p < 0.01, respectively). Similarly, post-operative BMI at 13-24 months was also significantly higher in the ant and post HI group on post-op MRI (p < 0.01). There was no significant difference between the two groups in terms of baseline adrenal insufficiency, thyroid insufficiency, gonadal insufficiency, IGF-1 levels, hyperprolactinemia, and diabetes insipidus. Diabetes insipidus was more common following surgery among those who had anterior and posterior involvement on pre-operative MRI (p < 0.05).

CONCLUSIONS

HO appears to be predetermined by tumor involvement in the posterior hypothalamus observed on pre-operative MRI. Posterior HI on pre-operative MRI was also associated with the development of diabetes insipidus after surgery.

Stereotactic radiosurgery as the initial management option for small-volume hypothalamic hamartomas with intractable epilepsy: a 35-year institutional experience and systematic review

OBJECTIVE

Young patients with hypothalamic hamartomas (HHs) often present with intractable epilepsy. Currently there are no established management guidelines for HH. The authors retrospectively reviewed their single-institution experience to delineate the role of stereotactic radiosurgery (SRS).

METHODS

Seven patients with HHs (4 females; median age 13.7 years, range 2.5-25 years) with no prior resection underwent SRS between 1987 and 2022. The clinical history, epilepsy profile, radiographic findings, and neurological outcomes were characterized. HH topographical types were classified according to the Régis classification. Outcome measures included Engel seizure classification, HH response, and the need for additional surgical interventions.

RESULTS

All patients had Engel class IV epilepsy. A Leksell Gamma Knife was used to deliver a median margin dose of 18 Gy (range 16-20 Gy) to a median hamartoma volume of 0.37 cm3 (range 0.20-0.89 cm3). Seizure reduction was confirmed in 6 patients, and 2 patients had regression of their hamartoma. Two patients underwent resection and/or laser interstitial thermal therapy after SRS. At follow-up, 1 patient was seizure free, 4 patients achieved Engel class II, 1 patient had Engel class III, and 1 patient had Engel class IV seizure outcomes.

CONCLUSIONS

SRS as the initial management option for HH was associated with a low risk of adverse effects. In this institutional series reviewing small-volume HHs treated with SRS, no adverse radiation effect was detected, and the majority of patients experienced seizure reduction. SRS should be considered as the first-line treatment for seizure control in patients with small-volume HHs.

[Hypothalamic hamartoma microsurgical resection using transcallosal transforaminal approach]

OBJECTIVE

Transcallosal transseptal interforniceal approach is recognized as the most appropriate route to resect sessile hypothalamic hamartomas but individuals with obliterated cavum septi pellucidi may pose difficulties to access these lesions safely.

MATERIAL AND METHODS

Six patients aged 8-34 years (med - 15.5) with the rather small (medial volume - 1.2 cm³) and in all but one cases the Delalande-Type II intraventricular sessile hamartomas and intractable epilepsy underwent surgery. The last patient had a rather larger lesion (Type III) encroaching both hypothalami and infundibulum. Cavum septi could not be distinguished on preop MRI in all cases. Lesions were removed via transcallosal transforaminal route using CUSA and foraminal walls dynamic retraction. In 4 cases the ipsilateral anterior septal vein was divided to expand the orifice of Monro foramen facilitating illumination and dissection.

RESULTS

Early postop course was uneventful in all cases. Total or near total lesion removal was revealed on post-surgery images in cases with Type II hamartomas. No one of patients with ligated septal veins exhibited any signs of venous infarcts. Median known FU is 3 years (14 months - 5 years). Three patients were free of every seizure at the last check (50%). Two other patients nevertheless persisting mild recent memory deficit, were able to live independently and reported rare non-disabling events. AE-medication was discontinued in 2 patients, in other three cases it was tapered and simplified.

CONCLUSION

In a subset of carefully selected patients with rather small Delalande-Type II sessile hypothalamic hamartomas in case of obliterated Cavum Septi Pellucidum the transcallosal transforaminal approach may be attempted in alternative to conventionally used transseptal interforniceal route with similar outcome and acceptable morbidity.

[Surgical treatment of epilepsy in patients with hypothalamic hamartomas]

The purpose of this review was to analyze the current ideas about various techniques and methods for treating epilepsy in patients with hypothalamic hamartomas including microsurgery, endoscopy, radiofrequency thermal destruction, stereotactic laser ablation and radiosurgery. Data characterizing their effectiveness, limitations and complications are considered.

CONCLUSION

When choosing the optimal treatment option, it is necessary to take into account patient age and course of disease, anatomical and topographic features of hamartoma location, previous attempts of treatment, opinion of the patient and his guardians, as well as surgical experience.

Successful Diagnoses and Remarkable Metabolic Disorders in Patients With Solitary Hypothalamic Mass: A Case Series Report

BACKGROUND

Solitary intracranial hypothalamic mass occurs rarely. The etiological diagnosis of solitary hypothalamus lesion is challenging and often unachievable. Although previous studies indicated that lesions affecting the hypothalamus often cause significant metabolic disorders, few reports about the metabolic disturbances of patients with solitary hypothalamic mass have been reported.

METHOD

Twenty-five patients with solitary hypothalamus lesions who had been evaluated and treated in Huashan Hospital from January 2010 to December 2020 were retrospectively enrolled. The clinical manifestations, radiological features, endocrine and metabolic disorders, and pathology were analyzed.

RESULTS

The male to female ratio was 5/20. The median age of onset was 22 (19, 35) years old. The most common initial symptom was polydipsia/polyuria (19/25, 76.0%) and amenorrhea (9/20, 45.0%). A high prevalence of hypopituitarism of different axes was found, with almost all no less than 80%. Central hypogonadism (21/22, 95.5%) and central diabetes insipidus (19/21, 90.5%) were the top two pituitary dysfunctions. Conclusive diagnoses were achieved by intracranial surgical biopsy/resection or stereotactic biopsy in 16 cases and by examining extracranial lesions in 3 cases. The pathological results were various, and the most common diagnoses were Langerhans cell histiocytosis (7/19) and hypothalamitis (5/19). The mean timespan from onset to diagnosis in the 19 cases was 34 ± 26 months. Metabolic evaluations revealed remarkable metabolic disorders, including hyperlipidemia (13/16, 81.3%), hyperglycemia (10/16, 62.5%), hyperuricemia (12/20, 60%), overweight/obesity (13/20, 65.0%), and hepatic adipose infiltration (10/13, 76.6%).

CONCLUSION

Either surgical or stereotactic biopsy will be a reliable and relatively safe procedure to help to confirm the pathological diagnosis of solitary hypothalamic mass. Metabolic disorders were severe in patients with solitary hypothalamic mass. The management of such cases should cover both the treatment of the primary disease, as well as the endocrine and metabolic disorders.

Magnetic resonance-guided focused ultrasound ablation of hypothalamic hamartoma as a disconnection surgery: a case report

We report the case of a patient with hypothalamic hamartoma (HH) who was successfully treated with magnetic resonance-guided focused ultrasound (MRgFUS) for ablation as a disconnection surgery. A 26-year-old man with gelastic epilepsy had been diagnosed with HH at 3 years of age, and antiepileptic drugs were administered due to worsening episodes. Magnetic resonance imaging showed a sessile parahypothalamic hamartoma and MRgFUS ablation was performed, creating an oval-shaped lesion at the boundary area of the HH. Dramatic improvements in seizure symptoms were noted, and he was seizure-free on decreased antiepileptic drugs without any adverse events over the 1-year follow-up period.

The implication of giant tumor size on surgical resection, oncological, and functional outcomes in craniopharyngioma

OBJECTIVE

Implication of the tumor size on oncological and functional outcomes of craniopharyngioma is inconsistently reported. The aim of this study is to assess the postoperative outcome of giant craniopharyngiomas (> 4 cm in diameter) and to elucidate the impact of tumor size on various outcome parameters and survival.

MATERIAL AND METHODS

Forty-four patients (children aged ≤ 18 years: 25; adults: 16) with giant craniopharyngioma, operated between January 2001 and December 2015, were included in this study. Various outcomes, progression-free survival (PFS) and overall survival (OS) were calculated.

RESULTS

Gross total resection (GTR) was achieved in 17 (39%) and subtotal resection (STR) in 27 (61%) patients. Eleven patients (25%) received radiotherapy (RT) after STR. Postoperatively, new cranial nerve and motor deficits were noted in 12 (27%) and 9 (20%) patients, respectively. Tumor recurrence following GTR and STR without adjuvant RT was diagnosed in 3 (17%), and 5 (38%) patients, respectively. Following STR with RT, one (9%) experienced recurrence. PFS at 5-, and 10- year following GTR, STR, and STR + RT was 80.8%, 45.4%, and 90%, respectively. At 5- and 10- year, OS was 86.5%, 77.9% and 100% following GTR, STR, and STR + RT, respectively. The rate of GTR was significantly lower in patients with giant tumors (39% vs. 62%; Chi-square test, p value 0.008). Postoperatively, neurological deficit (20%), hypopituitarism (95%) and hypothalamic dysfunction (26%) were significantly higher for giant craniopharyngiomas. Hazards of recurrence were not significant between giant and non-giant tumors (hazard ratio 1.86; 95% CI 0.94-3.68; p 0.07). There was no significant difference in OS between the patients with giant and non-giant tumors (log-rank test 2.1; p value 0.14).

CONCLUSION

Tumor size should be considered as an important predictor of the postoperative functional outcome. Although the rate of GTR is less than that of small tumors, the recurrence rate, progression-free survival, and overall survival of the patients with giant tumor are comparable to non-giant tumors.

Hypothalamic Hamartoma, Gray Matter Heterotopia, and Polymicrogyria in a Boy: Case Report and Literature Review

BACKGROUND

Hypothalamic hamartomas (HHs) are rare, and it is even rarer when combined with gray matter heterotopia (GMH) and polymicrogyria (PMG).

CASE DESCRIPTION

A 5-year-old boy with HH, GMH, and PMG was retrospectively evaluated. The clinical data, including the symptoms, examinations, diagnosis, and treatment, were collected. The patient had a chief complaint of gelastic seizures and intellectual deficiency. Brain magnetic resonance imaging showed HH, paraventricular nodular heterotopia, and PMG. Video electroencephalographs were normal. The patient underwent resection of the HH via transcallosal transseptal interforniceal approach. Seizures disappeared immediately after complete resection of HH, and the intellectual development improved.

CONCLUSIONS

In this extremely rare case, resection of the HH eliminated the symptoms. Nonetheless, we still need to be cautious about the possible epilepsy that may be caused by GMH and PMG.

Craniopharyngioma treatment: an updated summary of important clinicopathological concepts

INTRODUCTION

Craniopharyngiomas (CPs) are benign histological tumors that may develop at different positions along the hypothalamic-pituitary axis. Their close, heterogenous relationship to the hypothalamus makes surgical removal challenging even though this remains the primary treatment strategy.

AREAS COVERED

This article presents a critical overview of the pathological and clinical concepts regarding CPs that should be considered when planning treatment. Thus, we have performed a comprehensive review of detailed CP reports published between 1839 and 2020.

EXPERT OPINION

CP surgery should pursue maximal tumor resection while minimizing the risk of injuring the hypothalamus. Therefore, surgical strategies should be individualized for each patient. Accurate assessment of presenting symptoms and preoperative MRI has proven useful to predict the type of CP-hypothalamus relationship that will be found during surgery. CPs with dense and extensive adhesions to the hypothalamus should be highly suspected when MRI shows the hypothalamus positioned around the mid-third of the tumor and an amputated upper portion of the pituitary stalk. Symptoms related to functional impairment of the infundibulo-tuberal area of the third ventricle floor, such as obesity/hyperphagia, Fröhlich's syndrome, diabetes insipidus, and/or somnolence, also indicate risky CP-hypothalamic adhesions. In these cases, limited tumor removal is strongly advocated followed by radiation therapy.

Early Copeptin Determination Allows Prompt Diagnosis of Post-Neurosurgical Central Diabetes Insipidus

INTRODUCTION

Central diabetes insipidus (CDI) is a frequent complication of pituitary surgery, but its diagnosis lacks standardized criteria. Copeptin, a surrogate marker of arginine vasopressin release, is triggered by psycho-physical stresses such as pituitary surgery. Low postoperative copeptin could predict CDI onset. The aims of this study were the validation of copeptin as a predictor of post-neurosurgical CDI and the identification of the optimal timing for its determination.

METHODS

Sixty-six consecutive patients operated for a hypothalamic-pituitary lesion were evaluated. Copeptin was determined preoperatively and at 1, 6, 12, 24 and 48 h post-extubation. Fifty-eight patients were reassessed after 3-6 months post-surgery to confirm transient (3 cases) or permanent CDI (5 cases) diagnosis.

RESULTS

A marked copeptin peak was identified at 1 h after extubation, when a value below or equal to 12.8 pmol/L had a good accuracy in identifying CDI cases (AUC 0.866, 95% CI 0.751-0.941). Moreover, a copeptin peak above 4.2 pmol/L excluded permanent forms (AUC 1, 95% CI 0.629-1). Regression analysis identified copeptin as the only significant predictor of CDI (OR 0.86, 95% CI 0.75-0.98, p = 0.02). A copeptin T1/T0 ratio below or equal to 1.47 identified patients at risk of isolated biochemical alterations even in the absence of an overt CDI.

CONCLUSIONS

A prompt increase of copeptin is expected at 1 h after extubation. The absence of this peak is a reliable predictor of post-neurosurgical CDI.

Localised Langerhans cell histiocytosis of the hypothalamic-pituitary region: case report and literature review

INTRODUCTION

Langerhans cell histiocytosis (LCH) localised in the hypothalamic-pituitary region (HPR) is very rare, especially in adults. Diabetes insipidus (DI) is considered to be a hallmark of HPR LCH, while anterior pituitary abnormalities are usually seen as consequences of surgery, radiotherapy or chemotherapy.

CASE DESCRIPTION

We present a patient with localised HPR LCH with dominant anterior pituitary dysfunction and tumour mass effects but without DI. Seven years after surgery and local radiotherapy, she is stable. Control MRI shows no residual tumour growth and thorough physical examination is still without any signs of disease spread.

CONCLUSIONS

Anterior pituitary deficiency can appear without DI and not only as a consequence of LCH treatment. All patients with LCH should be screened for this endocrine abnormality so that appropriate substitution therapy may be provided.

Risk-adapted, long-term management in childhood-onset craniopharyngioma

PURPOSE

This report is a review of findings on the diagnosis, treatment, clinical course, follow-up, and prognosis of craniopharyngioma patients with special regard to clinical trials and long-term management.

METHODS

Literature search on Pubmed for paper published after 1994.

RESULTS

Craniopharyngiomas are rare, embryonic malformations of the sellar/parasellar region with low histological grade. Clinical manifestations are related to increased intracranial pressure, visual impairment, and hypothalamic/pituitary deficiencies. If the tumor is favorably localized, therapy of choice is complete resection, with care taken to preserve hypothalamic and optic functions. In patients with unfavorable tumor location (i.e. involvement of hypothalamic areas), recommended therapy is limited hypothalamus-sparing surgical strategy followed by irradiation. Irradiation has proven effective in treatment of recurrences and progression. Surgical lesions and/or anatomical involvement of posterior hypothalamic areas can result in serious sequelae, mainly hypothalamic syndrome.

CONCLUSIONS

It is crucial that craniopharyngioma be managed as a frequently chronic disease, providing ongoing care of pediatric and adult patients' by experienced multidisciplinary teams in the context of multicenter trials.

Epileptic network of hypothalamic hamartoma: An EEG-fMRI study

OBJECTIVE

To investigate the brain networks involved in epileptogenesis/encephalopathy associated with hypothalamic hamartoma (HH) by EEG with functional MRI (EEG-fMRI), and evaluate its efficacy in locating the HH interface in comparison with subtraction ictal SPECT coregistered to MRI (SISCOM).

METHODS

Eight HH patients underwent EEG-fMRI. All had gelastic seizures (GS) and 7 developed other seizure types. Using a general linear model, spike-related activation/deactivation was analyzed individually by applying a hemodynamic response function before, at, and after spike onset (time-shift model=-8-+4s). Group analysis was also performed. The sensitivity of EEG-fMRI in identifying the HH interface was compared with SISCOM in HH patients having unilateral hypothalamic attachment.

RESULTS

EEG-fMRI revealed activation and/or deactivation in subcortical structures and neocortices in all patients. 6/8 patients showed activation in or around the hypothalamus with the HH interface with time-shift model before spike onset. Group analysis showed common activation in the ipsilateral hypothalamus, brainstem tegmentum, and contralateral cerebellum. Deactivation occurred in the default mode network (DMN) and bilateral hippocampi. Among 5 patients with unilateral hypothalamic attachment, activation in or around the ipsilateral hypothalamus was seen in 3 using EEG-fMRI, whereas hyperperfusion was seen in 1 by SISCOM.

SIGNIFICANCE

Group analysis of this preliminary study may suggest that the commonly activated subcortical network is related to generation of GS and that frequent spikes lead to deactivation of the DMN and hippocampi, and eventually to a form of epileptic encephalopathy. Inter-individual variance in neocortex activation explains various seizure types among patients. EEG-fMRI enhances sensitivity in detecting the HH interface compared with SISCOM.

Splenectomy attenuates obesity and decreases insulin hypersecretion in hypothalamic obese rats

OBJECTIVE

Obesity-induced abnormalities, such as insulin resistance, dyslipidemia and hypertension, are frequently correlated with low-grade inflammation, a process that may depend on normal spleen function. This study investigated the role of the spleen in the obesity induced by monosodium glutamate (MSG) treatment.

MATERIALS/METHODS

MSG-obese and lean control (CON) rats were subjected to splenectomy (SPL) or non-operated (NO).

RESULTS

MSG-NO rats presented a high adipose tissue content, insulin resistance, dyslipidemia and islet hypersecretion, accompanied by hypertrophy of both pancreatic islets and adipocytes when compared with CON-NO rats. In addition, changes in nitric oxide response were found in islets from the MSG-NO group without associated alterations in inducible nitric oxide synthase (iNOS) or IL1β expression. MSG-NO also presented increased leukocyte counts and augmented LPS-induced nitric oxide production in macrophages. Splenectomy of MSG-obese animals decreased insulin hypersecretion, normalized the nitric oxide response in the pancreatic islets, improved insulin sensitivity and reduced hypertrophy of both adipocytes and islets, when compared with MSG-NO rats.

CONCLUSION

Results show that splenectomy attenuates the progression of the obesity modulating pancreas functions in MSG-obese rats.

Hypothalamic obesity

Hypothalamic obesity represents a rare diagnosis applicable to only a small subset of obese patients. It is important to identify, diagnose, and treat these patients. This article reviews the physiology of the hypothalamus, focusing on its role in regulation of hunger, feeding, and metabolism. The causes of hypothalamic obesity are discussed including genetic, anatomic, and iatrogenic etiologies. The complex hormonal environment leading to obesity is explored for each etiology and treatment strategies are discussed. Reproductive consequences are also reviewed.

First description of pharmacoresistant epilepsy due to independent bilateral hypothalamic hamartomas

Hypothalamic hamartomas (HHs) are rare developmental malformations consisting of mixed neurons and glial cells, usually unilaterally attached to the tuber cinereum or mammillary bodies. We report on two patients, both suffering from pharmacoresistant epilepsy, behavioural and cognitive disturbances. Ictal and interictal electroencephalographic (EEG) abnormalities appeared bilaterally and multiregionally with right-sided preponderance. Magnetic-resonance imaging (MRI) revealed independent bilateral hypothalamic hamartomas, more prominently on the right side. Endoscopic surgery of the right HH was performed in each patient, resulting in a significant seizure reduction in both cases. To the best of our knowledge, there are no other reports of independent bilateral HHs in the literature.

Intraoperative use of high-field MRI in hypothalamic hamartomas associated with epilepsy: clinico-pathological presentation of five adult patients

BACKGROUND

Hypothalamic harmartomas (HHs) are either occasionally associated with medically intractable epileptic syndromes or precocious puberty. Due to the extraordinary location and the expansive intra-axial growth, surgical resection is difficult and challenging without causing severe neurological, hypothalamic or endocrinological deficits, which account for higher mortality and morbidity.

METHODS

We present a series of five adult patients with drug-resistant epilepsy who had been operated on for HH using neuronavigation and intraoperative 1.5-T magnetic resonance imaging (MRI). In this retrospective investigation, we compared our surgical strategy and postoperative results to existing series.

RESULTS

During surgery, we identified remnant HH in the first intraoperative MRI control scan in three out of five patients. After re-segmentation of the residual lesion using neuronavigation, complete resection was achieved in two of the three patients as confirmed by final intraoperative and late follow-up MRI, raising the rate of total resections to four out of five patients. Two patients died during the observation period. One patient suffered from a permanent third nerve palsy and one from a transient monoparesis of the left arm. New endocrinological disturbances included diabetes insipidus centralis in two and secondary hypothyroidism and hypogonadism in one patient. Four out of five patients had favourable seizure control (Engel I or II) after 64.8 (34-83) months of mean follow-up.

CONCLUSIONS

Neuronavigation and intraoperative MRI are valuable tools to encounter difficulties while performing surgery in patients with HHs. Intraoperative resection control increases the amount of maximum resection.

Memory outcome one year after stereotactic interstitial radiosurgery in patients with epilepsy due to hypothalamic hamartomas

Epileptic seizures caused by hypothalamic hamartomas (HHs) are highly pharmacoresistant. Resective surgical approaches have shown some efficacy in controlling seizures; however, they bear a significant risk of postoperative mnemonic deterioration due to the close anatomical proximity of the HHs to structures essential for memory functions. We report on cognitive outcome in 26 patients with structural epilepsy due to HHs one year after interstitial radiosurgery. Individually, deteriorations occurred more frequently in declarative memory functions (in 20 to 50% of the patients), whereas more than 80% of the patients revealed stable or even improved performance in attentional functions. Preoperative better memory functions were associated with higher risk of postoperative performance decline. After radiosurgery, half of the patients showed more than 50%, and some up to 90%, of seizure reduction. Hypothalamic hamartoma volumes were significantly reduced at follow-up. Transient radiogenic edema found in 10/26 patients was not associated with further cognitive decline after radiosurgery. These results are highly relevant for therapeutic decisions and patient consultation on timing and choice of nonmedical treatment options for HHs.

Clinical review: Bariatric surgery following treatment for craniopharyngioma: a systematic review and individual-level data meta-analysis

OBJECTIVES

Craniopharyngiomas are rare low-grade tumors located in the hypothalamic and/or pituitary region. Hypothalamic involvement and treatment resulting in hypothalamic damage are known to lead to development of "hypothalamic obesity" (HyOb) in 50% of cases. The management of HyOb, associated with eating disorders and rapid comorbidities, is an important issue. Bariatric surgery is the most effective therapy for weight loss in patients with severe exogenous obesity. The aim of this systematic review and meta-analysis was to determine the 12-month outcome of bariatric surgery for HyOb due to craniopharyngioma treatment.

METHODS AND RESULTS

Relevant studies were identified by searches of the MEDLINE and EMBASE databases until January 2013. A total of 21 cases were included: 6 with adjustable gastric banding, 8 with sleeve gastrectomy, 6 with Roux-en-Y gastric bypass, and 1 with biliopancreatic diversion. After data pooling, mean weight difference was -20.9 kg after 6 months (95% confidence interval [CI], -35.4, -6.3) and -15.1 kg after 12 months (95% CI, -31.7, +1.4). The maximal mean weight loss was achieved by the gastric bypass group: -31.0 kg (95% CI, -77.5, +15.5) and -33.7 kg (95% CI, -80.7, +13.3) after 6 and 12 months, respectively.

CONCLUSIONS

In this largest ever published study on the effect of bariatric surgery on obesity after craniopharyngioma treatment, we observed an important weight loss after 1 year of follow-up. Larger studies are warranted to establish appropriate selection criteria and the best surgical technique to perform bariatric surgery.

Giant hypothalamic hamartoma: case report and literature review

INTRODUCTION

Hypothalamic hamartomas are very rare (1:200,000) and range in size from 17.9 to 18 mm. When their dimensions exceed 30-40 mm, they are classified as giant hypothalamic hamartomas.

METHODS

We present a 14-month-old boy with central precocious puberty and gelastic seizures in whom a magnetic resonance imaging scan revealed a giant hypothalamic hamartoma measuring 50 × 50 × 40 mm.

RESULTS

In the 11 cases described so far, we found that in comparison to the average-size lesion, giant hypothalamic hamartomas had a lower frequency of precocious puberty, but a similar frequency of seizures. The mean age at diagnosis was younger, and males were more affected than females. Magnetic resonance imaging results were similar with the exception of mass effect.

CONCLUSIONS

Giant hypothalamic hamartomas had a higher tendency to adhere to surrounding structures. Their invasiveness and cystic degeneration were frequent findings among the 11 studies. Surgical removal was ineffective in controlling refractory epilepsy and caused postoperative morbidity in all patients.

Temporal lobe epilepsy with hypothalamic hamartoma: a rare case

Refractory gelastic seizure is one of the most common clinical manifestations in patients with hypothalamic hamartoma (HH) and HH is usually regarded as the epileptogenic focus. A young female patient with a small HH and refractory seizures is reported here. However, both the seizure semiology and results of electroencephalogram monitoring indicated the right temporal region was the epileptogenic focus. Thus a standard right anterior temporal lobectomy was performed while the hamartoma preserved. There was a marked improvement in both seizure frequency and quality of life during a 13-month follow-up. The outcome supported the concept that independent epileptogenic focus outside of the hypothalamus might occur in patients with HH.

Outcome after bariatric surgery in two adolescents with hypothalamic obesity following treatment of craniopharyngioma

Treatment of craniopharyngioma (CP) in childhood can lead to severe, debilitating obesity with devastating medical and psychological outcomes. Despite sustained nutritional and exercise-oriented interventions, no efficacious medical option is available for hypothalamic obesity. We describe two adolescents who developed morbid obesity and significant comorbidities following diagnosis and treatment of CP, in whom bariatric surgery was achieved, illustrating a novel approach for symptomatic hypothalamic obesity, as well as positive and negative outcomes.

[Complications after transcallosal transseptal interforniceal resection of hypothalamic hamartoma: analysis of 37 cases]

OBJECTIVE

To summarize the post-operative complications of resection of hypothalamic hamartoma (HH) through transcallosal transseptal interforniceal approach.

METHODS

Thirty-seven HH patients, 26 males and 11 females, aged 8.7 underwent resection of the tumor via the transcallosal transseptal interforniceal approach. The symptoms and blood electrolytes were observed.

RESULTS

After operation blood electrolyte test showed that 8 cases were normal, 19 cases showed hyponatremia as prime abnormality, and 10 cases had hypernatremia primarily. Among the 19 cases with hyponatremia transient apathy occurred in 2 cases, general epilepsy occurred in one patient, continuous minor epilepsy occurred in another one, 4 patients suffered minor epilepsy, 25 had fever the temperature of 3 of which were beyond 40 degrees C, and 2 had transient diabetes insipidus and 1 had diabetes.

CONCLUSION

Resection of HH through the transcallosal transseptal interforniceal approach achieves significant improvement of gelastic seizures with fewer complications. The most common complication is disturbance of serum natrium, which, however, is mild and well managed.

GABA(A) receptor-mediated excitation in dissociated neurons from human hypothalamic hamartomas

The cellular mechanisms underlying intrinsic epileptogenesis in human hypothalamic hamartoma (HH) are unknown. We previously reported that HH tissue is composed predominantly of GABAergic neurons, but how GABAergic-neuron-rich HH tissue is intrinsically epileptogenic is unclear. Here, we tested the hypotheses that some HH neurons exhibit immature features and that GABA excites these neurons via activation of GABA(A) receptors (GABA(A)Rs). Gramicidin-perforated and cell-attached patch-clamp recordings were performed using freshly-dissociated HH neurons to evaluate GABA(A)R-mediated currents, Cl(-) equilibrium potentials, and intracellular Cl(-) concentrations. Single-cell RT-PCR and immunocytochemical techniques were used to examine cation-Cl(-) co-transporter (NKCC1 and KCC2) gene and KCC2 protein expression and molecular markers of maturation. From a total of 93 acutely-dissociated HH neurons from 34 patients, 76% were small (soma: 6-9 microm) and 24% were large (soma: >20 microm) in size. Under gramicidin-perforated patch recording conditions, GABA(A)R activation depolarized/excited large but hyperpolarized/inhibited small HH neurons in most cases. Compared to small HH neurons, large HH neurons exhibited more positive Cl(-) equilibrium potentials, higher intracellular Cl(-) concentrations, lower KCC2 expression, and an immature phenotype, consistent with GABA(A)R-mediated excitation. Taken collectively, we provide novel evidence for and mechanistic insights into HH epileptogenicity: GABA(A)R-mediated excitation.

GABAA receptor-mediated activation of L-type calcium channels induces neuronal excitation in surgically resected human hypothalamic hamartomas

PURPOSE

The human hypothalamic hamartoma (HH) is a rare, intrinsically epileptogenic lesion associated with gelastic seizures, but the underlying mechanisms remain unclear. Here, we examined the role of GABAA receptors in surgically resected HH tissue.

METHODS

HH tissue slices (350 microm) were studied using cellular electrophysiological, calcium imaging, and immunocytochemical techniques.

RESULTS

Two neuronal cell types were seen: small (10-16 microm) spontaneously firing GABAergic neurons and large (20-28 microm) quiescent neurons. In gramicidin-perforated patch recordings, muscimol (30 microM) induced membrane depolarization in 70% of large (but not small) neurons and a concomitant rise in intracellular calcium. These responses were blocked by bicuculline methiodide (50 microM). Depolarizing neurons also exhibited more positive reversal potentials (Emuscimol) and significantly higher intracellular chloride concentrations compared to those that hyperpolarized. The cation chloride co-transporters NKCC1 and KCC2 were coexpressed in the majority of large neurons, but fluorometric measurements revealed that 84% of large HH neurons expressed solely or relatively more NKCC1. Bumetanide (20 microM), a NKCC1 antagonist, partially suppressed muscimol-induced excitation in large neurons. Concordant with robust expression of CaV1.2 and CaV1.3 subunits in HH neurons, the L-type calcium channel blocker nifedipine (100 microM) prevented muscimol-induced neuronal excitation.

CONCLUSIONS

GABAA receptor-mediated excitation, due in part to differential expression of NKCC1 and KCC2 and subsequent activation of L-type calcium channels, may contribute to seizure genesis in HH tissue. Given the ready availability of L-type calcium channel blockers, our results have clinical ramifications for the treatment of seizures associated with HH lesions.

[Radiosurgery of hypothalamic hamartomas]

Hypothalamic hamartomas are relatively rare congenital tumors and present peculiar clinical symptoms such as convulsive and gelastic seizures, mental retardation, various abnormal behaviors as well as precocious puberty. We have treated 8 cases of symptomatic hypothalamic hamartomas with gamma knife surgery. There are 7 males and one female, ages ranging from 2 to 28 years (mean of 14.3 years). All the patients presented with convulsive and gelastic seizures, and some of them showed abnormal behavior and precocious puberty. At radiosurgery hypothalamic tumors, 8 to 22 mm in diameter (mean 13.5 mm), were treated with the mean maximum and marginal doses of 32.9 Gy and 18.5 Gy respectively. In general an entire tumor coverage was intended, but a few were partially covered, because of the tumor size as well as nearby sensitive structures like the optic nerve and the hypothalamus. With the mean follow-up of 53.7 months after the radiosurgery, generalized seizures were well controlled in 6 out of 8 cases, but gelastic seizures were not always controlled. In order to achieve an excellent seizure control and a favorable neurological outcome, a marginal dose of more than 18 Gy with total tumor coverage is definitely required. In conclusion, radiosurgery can play a role in treating hamartomas since neurological outcome and seizure control are apparently improved.

Transcallosal resection of hypothalamic hamartoma for gelastic epilepsy

INTRODUCTION

Hypothalamic hamartomas (HHs) are commonly associated with severe epilepsy resistant to anticonvulsant therapy. Historically, surgical resection of HHs resulted in considerable morbidity.

DISCUSSION

Two series of patients who successfully underwent resection using a transcallosal approach have now been published; we report the first UK experience of this technique in a series of five patients with HHs and gelastic epilepsy resistant to anticonvulsant therapy. Patients were assessed pre- and postoperatively for seizure activity, endocrine function, ophthalmology, and neurocognitive function. Two patients had precocious puberty and all had evidence of developmental delay and behavioral problems. Postoperatively, all children experienced at least a 50% reduction in seizure frequency with abolition of major seizure types; one child remains seizure-free. One child developed a mild postoperative right hemiparesis and one developed transient diabetes insipidus.

CONCLUSION

There were no adverse developmental effects of surgery. Transcallosal resection of HHs ameliorates resistant epilepsy syndromes associated with HH.

Operative technique: the anterior transcallosal transseptal interforniceal approach to the third ventricle and resection of hypothalamic hamartomas

Background. We have previously described the resection of hypothalamic hamartomas (HH) using a transcallosal approach [Transcallosal resection of hypothalamic hamartomas, with control of seizures, in children with gelastic epilepsy, Neurosurgery, 2001]. Since then, we have refined the technique and now describe in detail an anterior transcallosal transseptal interforniceal approach to the third ventricle as a variation of the standard transcallosal interforniceal approach. The results of this series are presented to demonstrate the safety and efficacy of this approach. Method. HH were resected via an anterior transcallosal, transseptal, interforniceal approach to the third ventricle. This is a more anterior approach to the third ventricle with a more acute trajectory than has been described previously. Results. This approach provided excellent access to the floor of the third ventricle with minimal forniceal retraction and avoidance of dissection of the deep venous structures. Transcallosal resection of HH was performed in 45 patients aged 2.9-33 years (mean 11.3 years). Morbidity was minimal, including transient hemiparesis in 3, ongoing diabetes insipidus in 2, early short-term memory impairment in 16 (persistent in 6) and one patient developed pneumonia postoperatively but recovered. Conclusion. The anterior transcallosal transseptal interforniceal technique is an effective and relatively safe technique when used for the resection of HH. This operative approach is applicable to other pathology in the third ventricle or hypothalamic region and has advantages compared with the standard transcallosal approach to the third ventricle.

Hypothalamic hamartoma treatment: surgical resection with the transcallosal approach

Multiple treatment options are available for patients with hypothalamic hamartoma (HH) including the frontotemporal approaches, the anterior transcallosal transseptal interforniceal approach, the transventricular endoscopic approach, and stereotactic radiosurgery. Relatively large patient series of the transcallosal resection/disconnection from Royal Children's Hospital in Melbourne and the Barrow Neurological Institute in Phoenix, AZ, show, respectively, that 52% to 54% are 100% seizure free, and 24% to 35% have >90% seizure reduction. However, there appears to be an 8% to 14% risk of persisting memory problems. The surgery should ideally be performed in the early years of childhood before secondary generalized epilepsy develops and developmental delay and behavioral problems are established. Radiosurgery may be a preferable option for higher-functioning adolescent or adult patients with HH. The choice of treatment must be individualized depending on the age and clinical circumstances of the patient and the size and anatomic relationships of the hamartoma. The transcallosal resection of HH is an effective and safe treatment, but there is a small risk of short-term memory impairment. The endoscopic approach is an alternative to the transcallosal approach for smaller HH.

Surgical management of hypothalamic hamartomas with epilepsy: the stereoendoscopic approach

OBJECTIVE

Hypothalamic hamartomas (HHs) require surgical treatment in patients presenting with refractory epilepsy.

METHODS

The authors report on a single-center series of 33 patients (24 males, 9 females) who underwent surgery between January 1997 and April 2004. They experienced several types of seizure (gelastic, tonic, partial, atonic, generalized tonic-clonic, dacrystic, infantile spasm, mental retardation, and behavioral and endocrinological abnormalities). Forty-nine interventions were carried out. Every patient, with the exception of the first, underwent hamartoma disconnection (pterional approach, six patients; endoscopy, 15 patients; both, 11 patients). The endoscopic approach was carried out with a frameless stereotactic system to enhance feasibility and efficacy of the disconnecting procedure.

RESULTS

Surgery-related neurological complications occurred in two patients, both after a pterional microsurgical approach. Furthermore, two patients experienced panhypopituitarism and one patient experienced transitory central insipid diabetes. All patients but one showed recovery or considerable improvement of their epilepsy (Engel Class 1, 48.5%; Engel Class 2, 3%; Engel Class 3, 45.5%; mean follow-up duration, 1 yr 7 mo).

CONCLUSION

According to the proposed classification of sessile HH into four types, the best candidates for endoscopic disconnection are Type 2 and Type 3 HHs. In the present series, 90% of patients affected by Type 2 HH became seizure free and the remaining 10% improved; of those with Type 3 HH at presentation, 35.3% recovered and 60% improved. Neuropsychological and endocrinological test results showed improvement in many patients. Data from our series demonstrate that frameless stereotactic endoscopic disconnection should be considered as the treatment of choice in the presence of favorable anatomic conditions.

Assessment of cognitive functions before and after stereotactic interstitial radiosurgery of hypothalamic hamartomas in patients with gelastic seizures

We assessed cognitive functions before and 3 months after interstitial radiotherapy in 14 patients with gelastic seizures caused by hypothalamic hamartoma. Cognitive functioning was assessed before temporary implantation of (125)I-seed and 3 months after seed explantation. Performance was compared with that of a selected control group of conservatively treated patients with symptomatic focal epilepsy tested before add-on treatment with a new antiepileptic drug and after reaching steady state. No short-term negative side effects of the interstitial radiosurgery could be observed for the domains of attention and executive functions and verbal and figural memory performance. Cognitive development of the patients treated with seeds was comparable to that of the control group at both assessments. Thus, the stereotactic implantation of (125)I-seeds in this patient group with gelastic seizures caused by hypothalamic hamartoma provides a well-tolerated minimally invasive method in the treatment of this severe epileptic syndrome without negative cognitive side effects.

Hypothalamic hamartoma associated with anterior paraclinoid aneurysm of the internal carotid artery

A 15-year-old boy presented with a history of medically refractory gelastic seizures and cognitive impairments. Neuroimaging demonstrated a sessile type hypothalamic hamartoma, which was treated by gamma knife surgery. However, the gelastic seizures only partially decreased and the frequency of seizures remained unchanged. One year later, angiography before surgery detected anterior paraclinoid aneurysm of the left internal carotid artery. Blood pressure and endocrinological examinations showed no abnormality. Direct surgery was performed to treat the aneurysm and hamartoma. No sclerotic changes were noted in the arterial wall. The aneurysm was treated with clipping, and the hamartoma was partially removed. Postoperative course was uneventful and the gelastic seizures disappeared. No evidence for a causal relationship between the hamartoma and aneurysm was found.

Transcallosal resection of hypothalamic hamartoma for intractable epilepsy

PURPOSE

To present the results of transcallosal surgical resection of hypothalamic hamartoma (HH) in 26 patients with refractory epilepsy in a prospective outcome study.

METHODS

Patients with refractory epilepsy symptomatic to HH were referred for surgical resection of their HH (mean age, 10.0 years; range, 2.1-24.2 years). A transcallosal, interforniceal approach was used to remove and/or disconnect the hamartoma. Volumetry was obtained on pre- and postoperative brain MRI scans to determine percentage of resection. Outcome assessment included determination of postoperative seizure frequencies in comparison to baseline and the incidence of postoperative complications. Postoperative changes in cognitive and behavioral functioning, in comparison to baseline, were elicited by parental report.

RESULTS

The average postoperative follow-up interval was 20.3 months (range, 13-28 months). Fourteen (54%) patients were completely seizure free, and nine (35%) had at least a 90% improvement in total seizure frequency. Parents reported postoperative improvement in behavior in 23 (88%) patients and in cognition in 17 (65%) patients. Transient postoperative memory disturbance was seen in 15 (58%) patients, but persisted in only two (8%). Two (8%) patients had persisting endocrine disturbance requiring hormone replacement therapy (diabetes insipidus and hypothyroidism in one each). With univariate analysis, the likelihood of a seizure-free outcome correlated with younger age, shorter lifetime duration of epilepsy, smaller preoperative HH volume, and 100% HH resection.

CONCLUSIONS

Refractory epilepsy associated with HH can be safely and effectively treated with surgical resection by a transcallosal, interforniceal approach. Short-term memory deficits appear to be transient for most patients, and family perception of the impact of surgery on cognitive and behavioral domains is favorable. Complete resection yields the best result.

Endoscopic surgery for hypothalamic hamartomas causing medically refractory gelastic epilepsy

INTRODUCTION

There is increasing evidence that removal or disconnection of hypothalamic hamartomas can lead to seizure control and improvement in behavior. The purpose of this study is to report our experiences with endoscopic removal of these hamartomas.

METHODS

This is a prospective review of the early outcome of 44 patients undergoing endoscopic resection utilizing frameless stereotaxis and a micromanipulator.

RESULTS

All patients had normal-sized ventricles. Complete removal was possible in 14 patients, 13 of whom were seizure free at follow-up. Four patients suffered complications that have persisted for more than 3 months: One had significant hemiparesis and three had persistent difficulties with short-term memory. Postoperatively, no patient suffered a permanent hormonal deficiency. In one patient who had undergone a previous attempt at transcallosal resection, the procedure was abandoned because of the lack of internal anatomic landmarks. In a second patient, insufficient mass could be removed due to the size of the lesion and the distorted anatomy. Consequently, 1 week later, the patient underwent a transcallosal approach.

CONCLUSION

In appropriately selected patients, sessile hypothalamic hamartomas can be removed completely or they can be completely disconnected from the hypothalamus with an acceptable risk. At least a year after surgery is needed to evaluate the efficacy of the procedure in terms of control of seizures and improvements in behavior and emotional ability.

Hypothalamic hamartomas--clinical, neuropathological and surgical aspects

INTRODUCTION

Hypothalamic hamartomas are rare congenital lesions of the tuber cinereum presenting with the classic triad of gelastic epilepsy, central precocious puberty and developmental delay. The clinical course in the majority is one of progression, commencing with gelastic seizures in infancy, deteriorating into more complex seizure disorders and resulting in a catastrophic epilepsy associated with a concomitant cognitive and behavioural decline.

OBSERVATION

Electrophysiological, radiological and pathophysiological studies have confirmed the intrinsic epileptogenicity of the hypothalamic hamartoma. Secondary generalised epilepsy seen in this condition is theorised to be through propagation via the mamillothalamic pathways with attachment to the mamillary bodies identified on MRI. Indications as to timing for surgery remain ill-defined although there is a theoretical argument to intervene before the development of secondary generalised epilepsy.

SURGICAL APPROACH

Currently, the most effective surgical route appears to be the transcallosal anterior interforniceal approach although newer approaches of endoscopic disconnection and radiosurgery are being assessed.

Successful resection of Hypothalamic Hamartoma with intractable gelastic seizures--by transcallosal subchoroidal approach

A 19-year old female with intractable gelastic seizures was found to have 0.7 x 1.8 x 1.8 cm elliptical mass on the floor of the third ventricle. The signal intensity on the Magnetic Resonance Imaging (MRI) was consistent with the Hypothalamic Hamartoma (HH). Ictal EEG demonstrated rhythmic 7 Hz waves over Fp2, F4, and C4 with spreading to the right temporal region and then bilaterally. Ictal Single Photon Emission Computerized Tomography (SPECT) showed hyperperfusion at hypothalamic and medial frontopolar regions. The patient underwent surgical resection using Trans Callosal Subchoroidal Approach (TCSA) to the third ventricle. Pathological finding confirmed the diagnosis of hypothalamic hamartoma. Following the operation, she has been seizure free up to 12 months. Thereafter, provoked seizures seldom occurred and there has been improvement in her memory, emotional control and independence. This appears to be the first report of this surgical approach for HH, which is less likely to disturb memory function compared to previously described interfoniceal approach.

Epilepsy related to hypothalamic hamartomas: surgical management with special reference to gamma knife surgery

OBJECTIVE

A large spectrum of surgical techniques can be proposed to young patients presenting with hypothalamic hamartomas (HH) associated with severe epilepsy. The aim of this report is to point on some clinical and anatomical parameters supposed to influence the choice of the surgical approach and to emphasize the specific role of radiosurgery.

MATERIALS AND METHODS

We reviewed both our experience and the recent literature based on a Pubmed search. Lateral pterional, midline frontal through the lamina terminalis, transcallosal interforniceal approaches, endoscopic treatment through the foramen of Monro, disconnecting surgery, radiofrequency ablation, brachytherapy and gamma knife surgery (GKS) were all considered. Mortality, morbidity, and efficacy of each of these techniques were compared. Specific limits, difficulties, and constraints were taken into account. Our experience of radiosurgery is based on a prospective trial which enrolled 60 patients with HH and associated severe epilepsy between October 1999 and December 2005.

RESULTS

Several surgical techniques can lead to a real reversal of the epileptic encephalopathy. The main factors for the decision-making process are the age, the size of the lesion and its anatomical type (according to our original classification), the severity of the epilepsy, and the severity of the cognitive/psychiatric comorbidity. In our prospective trial (GKS), 27 patients have a follow-up superior to 3 years. Among those, 59.2% have an excellent result with a dramatic behavioral and cognitive improvement and are completely seizure-free (37%) or have only rare non-disabling seizures (22.2%). No permanent neurological complication has been observed so far; three patients have presented a transient poïkilothermia. GKS is clearly the safer approach for these difficult patients. Young patients with severe epilepsy and comorbidity must be operated on using a curative approach as early as possible. Very large type VI or mixed type with a large component above the floor of the third ventricle must be disconnected and then the upper remnant can be ideally treated by GKS (staged surgery). Type V (rarely epileptic) and IV are frequently operable by disconnection. Type I HH deeply embedded in the hypothalamus are operated on by GKS efficiently and safely. Type II HH can be operated on either endoscopically or transcallosally or by GKS depending on the parents' choice and severity of epilepsy. In small type III HH, GKS is a safer procedure, due to the very close relationship to the fornix and mammillary bodies. In very large type III HH, transcallosal interforniceal approach is proposed but with significant risks especially concerning short-term memory. When the lesion is sufficiently small, GKS is globally offering the patient a rate of seizure cessation comparable to microsurgery with, however, a much lower risk (no neurological deficit reported till now).

CONCLUSION

Our first results indicate that GKS is as effective as microsurgical resection and very much safer. GKS also allows avoiding the vascular risk related to radiofrequency lesioning or stimulation. The disadvantage of radiosurgery is its delayed action. Longer follow-up is mandatory for a reliable evaluation of the role of GKS. The early effect on subclinical discharges turns out to play a major role in the dramatic improvement of sleep quality, behavior, and developmental learning acceleration at school.

Giant hypothalamic hamartoma operated through subfrontal approach with orbitary rim osteotomy

INTRODUCTION

Hypothalamic hamartomas are associated with precocious puberty, gelastic seizures and severe refractory epilepsy. Treatment options include surgical resection, radiofrequency and radiosurgery.

CASE REPORT

A 7-month-old girl presented with gelastic seizures and developmental delay related to a giant hypothalamic hamartoma. The patient was operated through a subfrontal approach. Intraoperatively the lesion appeared intimately adherent to the right internal carotid artery. Seizure control was improved after tumoral decompression.

CONCLUSIONS

Treatment of giant hypothalamic hamartomas should always include surgical resection, given the mass effect over surrounding vital structures. Subfrontal approach with orbitary rim osteotomy provides a wide exposure with minimal frontal lobe retraction. Close adherence of hypothalamic hamartoma to vascular structures may be present, requiring careful surgical manipulation.