Transcript
Dr. Gutiérrez: And the pointer? It's okay. In the historical background, we have a person who makes the first third ventriculostomy with open procedure. Nowadays, the endoscopic is the more useful. There's a lot of instruments to do that, so we can see. We're going to talk about a case report of a woman, 42 years old with carcinoma renal, who submitted [SP] nephrectomy one year previous, who has two brain metastasis, one in the right temporal lobe and the other one in the pons with Sylvian aqueduct obliteration with mild ventricular enlargement. Our premises were a patient with bad prognosis in short term who needs radiosurgery with mild ventricular enlargement with a high risk to develop hydrocephalus. The question was, can we solve both problems in the same procedure? It means local tumor control and ventricular enlargement and abide new procedures with the risk. And then we believed in this. The project evaluation was submitted to the Ethics Committee and the informed consent for the patient. The accuracy of our dedicated LINAC is 0.3 millimeters reproduce the result for other Novalis center. This is treatment who need very high accuracy. We have it. The images for the treatment are MRI 3.0 Teslas and a CT scan with 1-millimeter slice thickness.
Our therapeutical approach was divided in two times. In the first time, we treat the temporal lobe metastasis with 20 Gy at the isocenter. And in 1B radiosurgical third ventriculostomy, our target was the midpoint between the mamillary bodies and the infundibular recess that we see here. We use 100 Gy at the isocenter with 21 noncoplanar arcs with a collimator of 4 millimeters. The isodose distribution is "sand clock" we see here. This is not a painting, this is a poem. Look at the arcs distribution. More about the arcs distribution. There's a lot of human studies which use 100 Gy or more. The time of treatment was one hour.
In the second therapeutical approach was pons metastasis with fractionated treatment. The organ at risk were visual pathways, brainstem, hypothalamus, mamillary bodies, pituitary gland, and vertebral artery. All these received less dose than the tolerance. Our follow-up was clinical and in images. The first month was every week, the second month, every 15 days, and after every month. In this follow-up, in the evaluation, we include ophthalmologic, memory, pituitary hormonal levels between others. And the images, we make CT at first week, the second was at two weeks, and after every two months. We make MRI in the treatment day and every three months. This is the CT pretreatment. We found a ventricular index of 36%, and one week after we found a ventricular index of 32%. After of this, the ventricular index maintained between 30% to 32% despite the persistent aqueduct obliteration. The clinical was better. The Karnofsky index increased in 20%. This is the MRI pretreatment and three months after. We found decreases in the ventricular size. This is MRI pretreatment, this is the MRI three months after treatment. We've got, this is the 85 Gy isodose curve. Look at... We found here the circulation from the cerebral spinal fluid to the third ventricle at the interpeduncular cistern. During the complete follow-up, the patient never present neurological progression or alteration secondary to radiosurgery. The impairment was always secondary to systemic progression.
Our conclusions are, this report demonstrates, for the first time, the ability of a dedicated LINAC to perform a precise and effective third ventriculostomy. Maybe it could be an option for selected patients with obstructive ventricular dilatation without acute hydrocephalus with pathology with bad prognosis who needs to be treated by radiosurgery. And this is a phrase to remember. The radiosurgery was born to "destruction of intracranial tissues." If you have any questions, please, here. Thank you.
Our therapeutical approach was divided in two times. In the first time, we treat the temporal lobe metastasis with 20 Gy at the isocenter. And in 1B radiosurgical third ventriculostomy, our target was the midpoint between the mamillary bodies and the infundibular recess that we see here. We use 100 Gy at the isocenter with 21 noncoplanar arcs with a collimator of 4 millimeters. The isodose distribution is "sand clock" we see here. This is not a painting, this is a poem. Look at the arcs distribution. More about the arcs distribution. There's a lot of human studies which use 100 Gy or more. The time of treatment was one hour.
In the second therapeutical approach was pons metastasis with fractionated treatment. The organ at risk were visual pathways, brainstem, hypothalamus, mamillary bodies, pituitary gland, and vertebral artery. All these received less dose than the tolerance. Our follow-up was clinical and in images. The first month was every week, the second month, every 15 days, and after every month. In this follow-up, in the evaluation, we include ophthalmologic, memory, pituitary hormonal levels between others. And the images, we make CT at first week, the second was at two weeks, and after every two months. We make MRI in the treatment day and every three months. This is the CT pretreatment. We found a ventricular index of 36%, and one week after we found a ventricular index of 32%. After of this, the ventricular index maintained between 30% to 32% despite the persistent aqueduct obliteration. The clinical was better. The Karnofsky index increased in 20%. This is the MRI pretreatment and three months after. We found decreases in the ventricular size. This is MRI pretreatment, this is the MRI three months after treatment. We've got, this is the 85 Gy isodose curve. Look at... We found here the circulation from the cerebral spinal fluid to the third ventricle at the interpeduncular cistern. During the complete follow-up, the patient never present neurological progression or alteration secondary to radiosurgery. The impairment was always secondary to systemic progression.
Our conclusions are, this report demonstrates, for the first time, the ability of a dedicated LINAC to perform a precise and effective third ventriculostomy. Maybe it could be an option for selected patients with obstructive ventricular dilatation without acute hydrocephalus with pathology with bad prognosis who needs to be treated by radiosurgery. And this is a phrase to remember. The radiosurgery was born to "destruction of intracranial tissues." If you have any questions, please, here. Thank you.