Zdravko Heinrich

Radical surgery of a giant Galen's vein aneurysm using total circulatory arrest: case report.

BACKGROUND Arteriovenous malformations of Galens vein are a rare type of vascular anomaly. The complex anatomy of these lesions creates an extremely difficult management dilemma. We report successful surgical treatment of a 7-year-old patient with a Galens vein aneurysm. METHODS AND RESULTS A 7-year-old patient with slowly progressing gait disturbance, emotional instability, and strange behaviour is presented. A computed tomography scan revealed a high-density mass in the pineal region and cerebral angiography showed an aneurysm of Galens vein. We decided to perform surgical excision of the aneurysm. The operation was performed under hypothermic circulatory arrest with barbiturate cerebral protection. The patient had no signs of postoperative ischemic deficits, hemorrhage, or neurologic deterioration. CONCLUSIONS Various techniques have been described for the obliteration of Galens vein aneurysms, including direct surgical approach, staged operation, and transarterial, transvenous or transtorcular embolization. We present this patient to illustrate the use of hypothermic circulatory arrest and barbiturate cerebral protection for successful surgical excision of this complex vascular lesion. The combination of these techniques allowed us, in this case, to operate with reasonable safety on otherwise, difficult to treat aneurysm of Galens vein.

Implantation metastasis of malignant fibrous histiocytoma along the stereotactic biopsy tract.

The primary parenchymal sarcomas of the central nervous ystem (CNS) are extremely rare tumors with the incidence of .08–0.7% [1]. Imaging studies of CNS and other system should roceed before the final diagnosis of primary parenchymal sarcoma as been made. Due to the rarity of these tumors they can be easily isdiagnosed. It can be very difficult to diagnose such tumors from pecimen obtained with the stereotactic biopsy needle. Stereotactic biopsy of the brain lesions is common neurosurgical rocedure. This technique is simple, effective and caries low risk or serious complications, with diagnostic yield from 70 to 98% [2]. mplantation metastasis along the needle tract after the stereotactic rain biopsy is extremely rare complication. We describe first case f implantation metastases of the primary parenchymal sarcoma f CNS following stereotactic brain biopsy.

OUT-OF-FIELD DOSES IN CHILDREN TREATED FOR LARGE ARTERIOVENOUS MALFORMATIONS USING HYPOFRACTIONATED GAMMA KNIFE RADIOSURGERY AND INTENSITY-MODULATED RADIATION THERAPY

The purpose of this study was to measure out-of-field organ doses in two anthropomorphic child phantoms for the treatment of large brain arteriovenous malformations (AVMs) using hypofractionated gamma knife (GK) radiosurgery and to compare these with an alternative treatment using intensity-modulated radiation therapy (IMRT). Target volume was identical in size and shape in all cases. Radiophotoluminescent (RPL), thermoluminescent (TL) and optically stimulated luminescent (OSL) dosimeters were used for out-of-field dosimetry during GK treatment and a good agreement within 1-2% between results was shown. In addition, the use of multiple dosimetry systems strengthens the reliability of the findings. The number of GK isocentres was confirmed to be important for the magnitude of out-of-field doses. Measured GK doses for the same distance from the target, when expressed per target dose and isocentre, were comparable in both phantoms. GK out-of-field doses averaged for both phantoms were evaluated to be 120 mGy/Gy for eyes then sharply reduced to 20 mGy/Gy for mandible and slowly reduced up to 0.8 mGy/Gy for testes. Taking into account the fractionation regimen used to treat AVM patients, the total treatment organ doses to the out-of-field organs were calculated and compared with IMRT. The eyes were better spared with GK whilst for more distant organs doses were up to a factor of 2.8 and 4 times larger for GK compared to IMRT in 5-year and 10-year old phantoms, respectively. Presented out-of-field dose values are specific for the investigated AVM case, phantoms and treatment plans used for GK and IMRT, but provide useful information about out-of-field dose levels and emphasise their importance.

Hypopituitarism after gamma knife radiosurgery for pituitary adenoma

ABSTRACT Purpose: The aim of the study was to investigate the incidence of and risk factors for hypopituitarism after gamma knife radiosurgery (GKRS) for pituitary adenoma. Materials and Methods: We conducted a retrospective analysis of the pituitary function of 90 patients who underwent GKRS for pituitary adenoma at the University Hospital Centre Zagreb between 2003 and 2014. Twenty seven of them met the inclusion criteria and the others were excluded from the study due to pituitary insufficiency which was present before GKRS. Eighteen patients had non-functioning and 9 patients had secretory adenomas. Median patients’ age was 56 years (24–82). GKRS was performed using the Leksell gamma knife Model C. The median prescription radiation dose was 20 Gy (15–25) and the median tumor volume size was 3.4 cm3 (0.06–16.81). New onset hypopituitarism was defined as a new deficit of one of the three hormonal axes (corticotroph, thyreotroph, or gonadotroph) ≥3 months following GKRS. SPSS was used for statistical analysis, with the significance level at P<0.05. Results: During the median follow-up period of 72 months (range 6–144), 30% of patients developed new hypopituitarism after GKRS. This corresponds to incidence of one new case of hypopituitarism per 15 patient-years. Age, gender, tumor function, tumor volume, suprasellar extension, prescription dose of radiation, as well as dose-volume to the pituitary gland, stalk and hypothalamus were not predictive factors for the development of hypopituitarism. Conclusions: In our cohort of patients with pituitary tumors who underwent GKRS, 30% developed new hypopituitarism during the follow-up period.