Purpose of my web site
With the story below, I hope that I can provide information for people who are more or less in the same situation as I was then. That they will be prepared better for a life with cancer using the information on this web site. When I heard I had ependymomas, the first thing I did was searching for information on the Internet. I hardly found any.
Who I am
My name is Noor Jongboer and I live in Apeldoorn in the Netherlands together with Wout. I was born in Arnhem in 1963. I had no medical history before I received this type of cancer. In fact, I was never ill and even rarely had a cold. I was working full time when the misery started.
Sadly Noor died 6th of june 2006. In memory of her and to support fellow-patients Noor's website remains available.
1. The first signs
How it started
In January 1997, my left leg started to tingle, sometimes severe, sometimes less severe. I also had involuntary contractions of my leg muscles, making my legs 'shake'. Later, some parts of my leg felt really hot. Not on the outside but from within. This only lasted for a short time and then faded away. I did not feel any pain, so I paid little attention to it. I felt I could not see a doctor with such a 'vague complaint'.
In March 1997, I made a long walking trip in the Ardennes, Belgium, where after I discovered a big blister on my left foot. I did not feel anything! Closer examination proved that I did not have any feeling in the skin of my complete left leg! This was no longer a vague complaint, so I made an appointment with my family doctor.
This is a summary of my symptoms:
To the family doctor and neurologist
My family doctor took my complaint seriously and performed a neurological examination. His first thoughts were 'Lyme disease' or 'Multiple sclerosis' and he directed me to Dr. Van Leeuwen, neurologist in the nearest hospital (Lucas Hospital, Apeldoorn). He also performed a neurological examination and prescribed a few clinical neurophysiologic examinations:
Through the MRI
The results of these examinations were normal. Further examination was required so I went through a MRI-scan to see if this gave any result. And indeed, on the MRI-scan, four tumours were visible in the spinal cord canal. The neurologist thought of 'neurofibromatosis'. The only way to obtain information about the nature of the tumours was by removing and examining a piece of tumour tissue (biopsy).
The operation in Zwolle, the Netherlands
In June 1997, I was operated by Dr. Zeilstra in the Sophia Hospital in Zwolle. From the first tumour, located between the fourth and fifth thoracic spine (between the shoulder blades), a small piece of tissue was taken. After some weeks, I received the results of the tissue examination: it appeared to be EPENDYMOMAS.
2. What is an ependymoma?
An ependymoma is a relatively benign tumour that originates from so called 'ependym cells'.
I was told that when the foetus is formed, 'something' goes wrong causing incorrect cells to enter into the brain liquid (= spinal cord liquid = cerebrospinal fluid). These cells can attach, for some reason to, for example, the cerebral membrane or spinal cord membrane. If such a cell attaches to 'ependym cells', ependymomas can grow. I have never seen this information printed anywhere; it is purely oral information from the neurologist.
Cross section spinal cord
Below you can see how the spinal cord is build up. The nerves exiting the central nerve system on the back are used for touch (Sensory root). The nerves in the front are for movement (Motor root). My ependymomas are located in the centre of the spinal cord: the black dot in the grey field on the image right below.
3. What is the treatment?
When the biopsy indicated I had four ependymomas in my spinal cord, it was decided that I would receive radiation therapy. The ependymoma is, fortunately, a tumour that is sensitive to radiation. Because not only the four tumours required radiation therapy, but the total of the cerebrospinal fluid (to destroy all wrong cells), my complete spinal cord and skull received radiation therapy (with the exception of my face).
I received radiation therapy in the Sophia hospital in Zwolle by Dr. Van Beek. After having made the mask (this was dreadful), outlining the fields to be irradiated and measuring the lead blocks, I received 28 treatments. First, 20 times on the complete surface (spinal cord and head) and then 8 times only on the part between my shoulder blades, where the four tumours were located. Each day, I received an amount of 1.8 Gray (Gy) (fractionated dose). The maximum dose the spinal cord can take is, according to literature theory, between 40 and 50 Gy. However, the amount that is necessary to destroy ependymomas lies between 50 and 60 Gy. Naturally, this depends on of the place and the size of the ependymoma. I thus received a total amount of 28 x 1.8 Gy = 50.4 Gy.
Irradiation of my ovaries
After four treatments, the radiologist discovered, (how surprisingly), that my ovaries were also in the radiated area. The type of radiation for the bottom part of the spinal cord was changed: from gamma radiation to electron radiation. With this last type, the depth of radiation can be controlled. So my cerebrospinal fluid was radiated but not the ovaries that lay behind.
I think it was a blunder of the radiologist to irradiate my ovaries in the first place. If my ovaries had received the complete amount of gamma radiation, I probably would have become sterile and reached menopause!
Here, you see a part of the outline and, if you look closely, the operation cicatrises.
Immediately at night after the first radiation, I became sick. Three hours after the first dose of radiation I became terribly sick and had to vomit. From that moment on, I was terribly sick. I couldn't keep anything down, even water was difficult. The next day, I received medication from the radiologist to reduce vomiting; these did not help a single bit. Then, I received stronger medicine that did help. After this, I felt better, although I had little appetite and therefore strongly lost weight (in the first week, I lost 5 kilo's). The reason for my sickness was related to the fact that the radiation went through the spinal cord, hitting other organs, including stomach and intestines, according to the radiologist.
After approximately two weeks, several side effects started to appear (in the flyer 'Radiotherapy', published by the Dutch Cancer-control (Nederlandse Kankerbestrijding) , these side effects are mentioned in detail):
Exactly a year after the last radiation, I was on holiday in Canada (September 1998) and walked, without too many problems trips of 25 km a day!!! I could not have imagined this a year before: at that time, a journey to the bathroom could sometimes be very tiresome.
This is what I looked like at the end of the radiations!
Because of the radiation, I got 'Lhermitte's syndrome'. When I tried to put my chin on my chest, therefore stretching my neck, I felt a type of tingling running on my back. Not terribly pleasant but also not painful. Fortunately, after a couple of months this faded.
Results of the radiation
In February 1998 (approximately four months after the last radiation), I went through the MRI scan again to see if the treatment had worked. Well, it certainly had: I was entirely "clean"! In the spinal cord no tumours were to be seen. The neurologist was very satisfied, and of course I was too! I had to come back in February 1999 for a check scan. This was very tense but again this time I was entirely clean and therefore all right. The next check scan was in 2001. I felt good, was not tired anymore and worked 32 hours a week. All in all, it has occupied me for almost a year.
4. What are the prospects?
Unfortunately, there is little to say about this. Doctors react very distantly when you ask about it: "not even a guarantee to the door". And there is little information concerning the life span because it does not occur frequently. The neuro surgeon told me that approximately 5 persons in the Netherlands had something similar in the past 50 years. I am, in fact, glad that I have not been given a prognosis. I do not ask for it any more. Because, what can I do with the result? I will wait and see how it all develops.
Things that, after this period, still bothered me were: still no feeling in the skin of my left leg, a 'slower' right leg (I did not dare to run) and, when I am tired, a light balance impediment. That was in fact the most cumbersome, but this was no problem when I was focused. My sweating had also changed. In former days, I only sweated when I made an extreme effort. But now I sweat, in a manner of speaking, only by thinking about a physical effort. Especially on my head, but that was nothing new, but now I also sweat in my neck, on my shoulders, my back, my forearm/wrists and my feet/ankles.
After the operation and the radiation
After the operation and the radiation During our holiday in Canada (Canadian Rockies) in September 1998, I slowly rebuilt my condition by first making small, short and flat trips and then steeper and longer trips, up to 25 km! I was very proud of myself!
After more than a year, I declared myself entirely healed. I did everything like I used to, my condition was OK and the tumours had disappeared! I agreed with the neurologist that I would have and MRI scan check every other year.
Looking back on this period, I find that I have received many positive things due to my sickness. I have, for example, much more understanding for people with (chronic) sickness, I can much better put myself in someone else's situation, I have learned who my real friends are (a stereotype, but nevertheless very true), the relation with my partner has deepened, I am more open for other people's stories, without wanting tell my story. And I do not make a fuss about things, I can put things in perspective much better. I have always enjoyed life, and I will keep doing so.
One last remark: I have always been optimistic and positive, that is my nature. Not for one moment I have thought that I would not survive. Only later, I realized that my close relatives thought I might not. Maybe they have had more difficulty with the whole situation than I had.
This was at Christmas in 1999
5. And then it became 2003 ...
During the Easter holidays in 2003 (April 20 and 21) I was sitting in the sun, reading a book. In the evening, I got a little pain under my right shoulder blade. First I thought of muscular pain, because maybe I had been sitting in the garden chair in a wrong position, but the pain did not go away and the skin at the right-hand side under my breast felt numb. Therefore, I went to the general practitioner on 5 May. He thought it could be a neck hernia or perhaps it had something to do with my ependymomas. He advised me to make an appointment with the neurologist.
Through the MRI again
On May 13, I had an appointment with Dr. Van Leeuwen and after I told my story, I was neurologically examined extendedly. The conclusion was: through the MRI-scan again, because it was no neck hernia and the numb feeling was on the same level as the earlier tumours. Because I also had pain in my back and a cramp in my right leg, my neurologist decided also to make scans of my lower back. On May 27 2003 I went through the MRI-scan and on June 11, I got the result.
On the scans, you can clearly see a round 'thing' in my spinal cord central canal. Not white, like the tumours in the previous scans in 1997, but black with a white ring around it. It seemed to be a cyst (a little bubble filled with fluid). But if a cyst is seen, then - according to Dr. Van Leeuwen - there is a tumour at hand. The tumour is still very small; you cannot see it on the scan yet. Van Leeuwen did not know how to treat this. We decided that he would send the scans to Dr. Zeilstra, the neuro surgeon from the Sophia hospital in Zwolle, who operated on me in 1997. While waiting, my situation declined rapidly . Walking became difficult; going up and down the stairs was even more difficult. The pain in my right side expanded to the left side, the numb feeling became worse and reached my right leg.
Dr. Zeilstra examined the scans and recommended an operation; it was the only way to see what was going on. He indicated clearly that I should not expect too much of the operation and that I it would be possible that it could be worse after the operation. Because the decay process went so fast, I decided to take the risk. Doing nothing seemed worse.
On 23 June 2003, I walked into the hospital with crutches and on 24 June, I had my operation. When I recovered after the operation, Dr. Zeilstra stood ad the end of my bed and informed me that he didn't even reach the tumour, so nothing had been done. My right leg was paralyzed; I could only move my toes and I could, with a lot of effort, move my left leg, but much less than before the operation. After the drain was removed from the wound and the cerebrospinal fluid was no longer discharged, the strength in and the feeling of both legs disappeared. I had a complete paraplegia from the 4th thoracic vertebrae (at the level of my breasts).
Stay in Sophia hospital in Zwolle
I have been in hospital in Zwolle for six weeks. Not a pleasant time. I probably got meningitis there; in any case, I have been treated for that (I had antibiotics for 10 days). Also, I got thrombosis in my left leg, despite the daily doses fraxiparine (nadroparine calcium) in my abdomen. Because of the thrombosis, I also got thrombolytics (acenocoumarol) and regular check ups by the thrombosis service.
Due to the paraplegia, I have no longer control concerning my bladder and anus. This incontinence is a very nasty consequence of the paraplegia, maybe more terrible than the fact that I can no longer walk. Through order and structure, my excrement could be regulated and as far as my urine is concerned, I have a suprapubis catheter. That is a tube of approximately 40 cm long, which goes through an opening in the abdomen into the bladder. At the end of the tube, I can empty my bladder regularly with a little tap.
Second opinion in the Daniel den Hoedkliniek
Second opinion in the Daniel den Hoedkliniek From the Sophia hospital in Zwolle, on July 22, I went with an ambulance to the Daniel den Hoedkliniek for a second opinion. The Daniel den Hoedkliniek is a clinic, specialized in cancer. The clinic is a part of the Erasmus University in Rotterdam.. There Dr. Enting recommended a check up through the MRI every four months and self research to the borders of feeling/no feeling in the skin. Should there be metastasis or growing of the tumour, then she recommended chemotherapy. Unfortunately, there was a minor chance (20% up to 30%) that this chemotherapy would succeed, but it was the only thing that might help. Radiation was no option, because I had the maximum doses six years ago. Radiation now would cause more damage than that it would help.
To the rehabilitation centre
When finally my operation wound was closed (it took some time and effort) and I had been released of all infusions, I could go to a rehabilitation center. I chose for Kastanjehof in Apeldoorn, because we live there and I expect more visitors. More about this later on.
Tumours and chemotherapy
On 26 November 2003, I went for a check through the MRI-scan in Apeldoorn. The neurologist, Dr. Van Leeuwen, phoned me later that the scans showed an increase of the tumour. In consultation with the Daniel den Hoedkliniek it was decided not to perform chemotherapy for the time being. They will do that if there are metastases, but I had to go through the MRI-scanner on a regular basis to watch the tumour closely.
Metastasis in my head
And so on 5 April 2004 I had another MRI-scan. For the first time a scan entirely from head to tumour. This lasted about two hours, where I was lifted on and off the table, so they could slide another antenna under me. And I was injected with contrast fluid. On 21 April 2004, Wout and I went to the neurologist for the result. There was a metastasis of the tumour in my head, near my brain stem! The neurologist said that it was a 'life-threatening tumour'. After hearing this bad news, we were frightened and sad.
Again to the Daniel den Hoedkliniek
The neurologist immediately made an appointment for us with Dr. Van den Bent of the Daniel den Hoedkliniek in Rotterdam (Dr. Enting did not work there anymore). On Monday 26 April 2004 Wout, my mother and I went there, armed with a pile of MRI-scans of the Lucas hospital in Apeldoorn. Van den Bent had, of course, no time to examine them well, but he had seen that on the scans which were made in September 2003, a small brain tumour was seen ("if you know where to look"). He told us to start chemotherapy only when I would get problems, such as seeing double or getting more pain. We disagreed because we had experienced that, once the problems begin, they will rapidly worsen: we did not want to be late any longer. He answered us that he would reflect the options and examine all the scans; also, he would discuss it with his colleagues.
Does the tumour grow?
During the next visit on 17 May 2004, it appeared that Van der Bent was not convinced that the tumour had really grown. The MRI makes 'slices' of the tumour. This could mean that the slices of the scan of September 2003 and April 2004 have not been made at the same place of the tumour. For example in September on the edge of the tumour and in April exactly in the middle. Then it looks as if the tumour has grown, but it does not have to be so. I hope that the drawing below makes that clear.
Another scan again
On 16 June 2004 I went through the MRI-scan in Apeldoorn again. The scans were sent to Van den Bent. He rang afterwards that he had examined the scans. The tumour in my head seems stable but the tumour in my back grows. On 30 June, my situation was reviewed in a team of colleagues and experts. It was decided that I had to go through the MRI-scanner in Rotterdam, because the MRI-scans from Apeldoorn were 'junk'. On the scans from Apeldoorn, he could not see the growth of the tumours. Because of Van der Bent's holidays, the next MRI-scan was planned on 20 August 2004.
Because the pain increased, I asked if this appointment could be made earlier. And fortunately, it was possible to see Dr. Taal, Dr. Van der Bent's substitute, on Thursday 22 July. He examined me and decided that it was indeed serious and he arranged that I could to through the MRI the next Monday, 26 July. Homage!
After the MRI-scan, we consulted Dr. Van der Bent, who was back from his holidays. He also recognized the seriousness of the situation and suggested that I stayed in the Daniel den Hoedkliniek to start chemotherapy. I was very glad of course; finally, the action I was waiting for.
So I was admitted on July 26 2004 and on the 28th, I got the first sacks with the cytostatics (cisplatin and etoposide). I got medicines against nausea and those worked well. The week after the cure, I was tired but afterwards I had totally recovered. However, my hair had fallen out and I was bald for the second time in my life.
On August 17, I went to Rotterdam for the second cure. This cure also went very well, but my hearing had clearly diminished. During the check interview with my internal medical specialist, Dr. Van der Rijt, it appeared that she hesitated to give me a third cure with cisplatin because this would damage my hearing irreparable. I could become entirely deaf. That is, as she said, "an undesirable side effect". The admittance scheduled for the third cure, on Tuesday September 7, was cancelled.
On September 10 I revisited the Erasmus MC-Daniel den Hoed Cancer Center to have a blood test, a hearing test and an MRI-scan taken. Afterwards I had an interview with Dr. Van den Bent and my internist. My blood was all right, my hearing clearly degraded (especially at high frequencies) as had also been concluded on August 17 and the tumour in my back has `not become smaller', as Dr. Van den Bent expressed it. On the MRI-photographs taken before the cures the tumour in my back had a size of 8.6 cm (3.3 inch) . The growth was too minor to be able to determine that the tumour had grown, but it certainly didn't get any smaller.
Again my case was discussed in `the large meeting'. Because cisplatin and etoposide induced no improvement it was concluded that the use of these drugs would be stopped. They now wanted to try another drug/chemical substance: temozolomide. This is a chemotherapy that is distributed in tablets. The cure is divided in cycles of 28 days, during the first 5 days of a cycle the chemotherapy is taken (on an empty stomach, preceded by a tablet against nausea) and on the 18th day blood is checked. For me taking tablets implied that no hospital admission was needed and I could take the cure at home. That went fine. I had no side effects and my hair started to grow again.
On December 20th I entered the MRI-scanner again to see whether the new cure had any effect. Unfortunately the photographs showed that the cure did not take effect; the tumour in my back had grown 2 cm (0.8 inch). Dr. Van den Bent indicated that no further therapies were available, not even experimental. He inquired with colleagues both nationally and internationally but this yielded no results. I did not ask for my prognosis; because I don't want to know.
Dr. Van den Bent indicated that, if the tumour would keep growing, first my arms would be paralyzed and then the tumour would reach the respiratory nerves - which would be the end. He would send his observations and conclusions to Dr. Zeilstra - my neuro surgeon from Zwolle - and together with him I should decide what to do next. This last conversation with Dr. Zeilstra in February 2005 was ineffectual. He indicated that I could ask for a second opinion from another neuro surgeon or another radiologist about radiation of the tumour, but that I would get the same answer: `We cannot help you any more'. In the mean time I started to search for cures in alternative treatment and decided to try these first.
6. Rehabilitation, new residence and adapted car
In the mean time many other developments took place. On August 5 2003 I went from the hospital in Zwolle to the rehabilitation center Kastanjehof in Apeldoorn by ambulance. One of the first things I needed to learn was the transfer from wheelchair to bed with a sliding board. At first I found it very frightening, but now I can do it (figuratively speaking) with my eyes closed.
Here you see someone making a transfer with a sliding board.
Additionally I had to try to sit in my wheelchair as much as possible. During the first two weeks in Kastanjehof I made huge progression. Every day I learned something new. After a few months I could wash myself using the shower (on a toilet/shower chair) and I could dress myself (including elastic stockings) without any help.
Unfortunately, in October 2003 my arms got overloaded (shoulders, elbows, wrists and thumbs). This happened because I, using a timer on my new watch, was lifting myself every twelve minutes. That is I lifted my upper body so that the buttocks came loose from the wheelchair's seat to stimulate the blood flow and prevent pressure sores. That is what the nurses and therapists told me to do. I was forced to cancel fun therapies like table tennis, badminton, and wheelchair training and during physiotherapy my arms were frictionally massaged and treated with ultrasound. I stopped immediately with lifting myself every twelve minutes.
From October 2003 I went home every weekend. In the living room we had a high-low adjustable bed and a toilet chair from the home care organization. The local government decided that our present house (a terraced house) was not adaptable to a wheelchair user and therefore we were forced to look for a new residence. We found a large apartment in `De Spreng' in Apeldoorn. On September 13 2004 after reconstruction of the of the bathroom we moved in.
Discharge from Kastanjehof
After that I was clinically discharged from Kastanjehof but revisited it two times a week for physiotherapy and ergotherapy (polyclinically. On December 22 2004 I had my last therapy session and I left Kastanjehof for good . Because I want to watch my weight, I will go back occasionally to use their scales on which I can weigh myself in my wheelchair.
During my stay in Kastanjehof I stood regular in the 'table to stand'. That is an machine in where I can stand right up on my own legs. This is necessary for a better blood circulation, to keep the muscles streched and reducing osteoporoses and decubitus. Also at home I need to stand in the 'table to stand' for a better health. Mine insurance company got me my onw ´table to stand`.
Many people ask me how it works. See the pictures below.
wheel chair to 'standing table'
Adjusted car and new driving license
Despite bad prospects I simply continued life. I really wanted to go back to work and thereto I needed an adjusted car. In March 2004 I had three driving lessons in an adjusted instruction car: no foot pedals but manual operated gas and breaks and of course fully automatic gear. After these three lessons I had to take a driving test at the CBR (central office for driving ability, the Dutch organization issuing driving licenses) and I was happy that I passed with a good result. I now have a driving license which states which special adjustments my car needs.
Then I bought a Renault Kangoo which had a small elevator to lift my wheelchair into the car behind my seat to give my still vulnerable shoulders some relief. It was adjusted to my needs by the Bever firm. Then it turned out that my present wheelchair with its fixed frame and large weight (32 kg) did not fit into the Kangoo. Therefore, I received a separate wheelchair, a TiLite SX, that can be folded and does not weigh as much (16 kg).
My TiLite wheelchair, made of titanium.
The Kangoo I had to pay myself but the adjustments to the car were paid by the UWV (Social Security Organization). I have to say that I can't complain about the people that arrange and pay for my aids.
7. Alternative treatment
After an extensive search on the Internet I decided to take the Non Toxic Tumour Therapy (NTTT). Also through the Internet I found the nearest medical doctor practicing natural treatment: Dr. B.R. De Klyn in Ellecom. On January 10 2005 I had my first interview. After a physical examination and a `living blood analysis' he prescribed me a diet, complementary drugs and supplements.
Living Blood Analysis
During a `living blood analysis' Dr. De Klyn takes a drop of blood and examines it with a microscope. It turned out that my red blood cells clot together too much and too few white blood cells were present. To make the blood better and less polluted and to get more white blood cells the supplements were prescribed. Already at the next blood analysis my blood had improved: the red blood cells were not clotted together so much any more. `This looks promising', Dr. De Klyn said.
Dr. De Klyn indicated that he cannot heal me, but that I have to do that myself. He can create the conditions so I, that is to say my immune system, can fight the tumour.
For this purpose the NTTT uses four elements, that I will describe briefly:
Iscador turns out to have as a contra-indication high intracranial pressure and is discouraged for people with brain or spinal cord tumours. As a consequence of this, this drug was not suitable for me. Up to a certain strength it could be used. It cannot be administered orally, because makes it ineffective. It has to be injected and preferably close to the tumour. Wout gave me the injections in my back. When I reached maximum strength I switched to Isorel.
Isorel is a product comparable to Iscador (made from mistletoe as well) but without the side effects of heightened intracranial pressure. It should be injected intravenously, that is in a vein. Thereto three tubes of blood were taken and then I had three infusion with Isorel. Then three tubes of blood were taken again and showed that Isorel took effect. It was decided that every week I would get an Isorel infusion. After a lot of hassle with the general practitioner and the pharmacist I was able to arrange that the home care organization would give me the infusion every week. That way I don't have to travel to Ellecom every week. The Thymus I inject three times a week into my upper legs; no problem for I don't feel it anyway.
Following Dr. de Kleyn's advice I am on Houtsmuller's diet; a modern variant of the well known Moerman diet. This diet consists of whole meal products, no meat (except liver and sweetbread) and no sugar. The most important aspect is to eat a lot of fruit and vegetables. I try to stick to the diet as much as possible, but sometimes I deviate, life should stay pleasant as well. More information on Houtsmuller's diet is available at Houtsmuller diet.
In the mean time I also had a `beta-examination'. Beta is acronym derived from Bio-Electronic Terrain Analysis according to prof Vincent. Blood, saliva and urine are examined. Measurements are performed on three criteria: accidity (pH), redoxpotential (rH2) and electrical resistance.
My blood and saliva were OK but my urine was so different from normal values due to a chronic bladder inflammation, that no values could be obtained. A complete image could therefore not be made.
How is my health after half a year of natural treatment?
Now I have been in Dr. de Klyn's care for half a year. I felt well and energetic during this period. I even started working again. Twice a week I drive to work to Arnhem in my Kangoo and work there from 10.30 till 15.00. Wout and have also been on holiday to France (L'Accolade).
After my return from France I had increasing pains, not only at the location of my spinal cord injury but also in my armpits. It woke me up during the night. Sometime later I noticed that parts of my arms and legs turned numb. In consultation with my general practitioner I found the right pain killer: OxyContin (an opium preparation) and hopefully my arms will not be affected too soon. Of course I knew that if the tumour kept growing my arms would go numb and lame, but I had not anticipated that it would come with so much pain.
When I started losing control over the strength in my hands and arms I stopped the treatement.
If you are want to know more about me and/or my disease, take a look at the thesis my sister-in-law Marianne made for her homeopathy studies.