Maginito a Maginito Opangidwira
MRI imayimira kujambula kwa maginito . Dzina lenileni la phunziro ili ndi nuclear magnetic resonance image (NMRI), koma pamene njirayi ikupangidwira kuti igwiritsidwe ntchito mu chithandizo chaumoyo mawu akuti "nyukiliya" amamveka kuti ndi olakwika kwambiri ndipo anasiya dzina lovomerezeka.
MRI imachokera ku mfundo zakuthupi za nyukiliya magnetic resonance (NMR), njira yomwe amagwiritsidwa ntchito kuti adziwe zambiri za mtundu wa mamolekyu.
MRI Imagwira Ntchito Bwanji?
Poyamba, tiyeni tiyang'ane mbali zina za makina a MRI. Zowonjezera zitatu za makina a MRI ndi awa:
- Makina aakulu
Mbali yaikulu kwambiri ya MRI ndiyo maginito aakulu . Kupanga mphamvu yamaginito yogwira mphamvu kuti apange mafano a MRI inali vuto lalikulu loti ligonjetse pa chitukuko cha sayansiyi. - Maginito amphamvu
Maginito a " gradient " ndi "kukonza bwino" mbali ya makina a MRI. Amalola kuti MRI iganizire mbali inayake ya thupi. Magetsi amphamvu amachitanso "phokoso losokoneza" mu MRI. - Chophimbacho
Pafupi ndi gawo la thupi lanu mukujambula ndi coil . Pali mapepala opangira mapewa, mawondo, ndi ziwalo zina za thupi. Chophimbacho chidzatulutsa mpweya womwe umapangitsa kuti MRI ichitike.
Magnet Primary
Maginito osatha (monga mtundu womwe mumagwiritsa ntchito pa firiji yanu) yomwe imakhala yogwiritsidwa ntchito mu MRI ingakhale yotsika mtengo kwambiri ndipo imakhala yovuta kwambiri kusunga.
Njira yina yopangira maginito ndiyo kuyiritsa waya wamagetsi ndikuyendetsa zamakono kupyolera mu waya. Izi zimapanga maginito pakatikati pa coil. Kuti apange mphamvu yamphamvu yamaginito kuti achite MRI, zida za waya siziyenera kukana; motero amatsukidwa mu helium yamadzimadzi kutentha madigiri 450 Fahrenheit pansi pa zero!
Izi zimapangitsa makompyuta kukhala ndi maginito a Tesla 1.5 mpaka 3 (mphamvu ya madokotala ambiri a MRIs), opitirira 20,000 oposa mphamvu ya magnetic.
Magnetti Achikulire
Pali maginito atatu aang'ono mkati mwa makina a MRI otchedwa gradient magnets. Magetsi awa ndi ang'onoang'ono omwe maginito oyambirira (pafupifupi 1/1000 ngati amphamvu), koma amalola mphamvu ya maginito kusinthidwa molondola. Ndi maginito awa omwe amalola zithunzi "magawo" a thupi kuti apangidwe. Pogwiritsa ntchito maginito amphamvu, maginito amatha kugwiritsidwa ntchito makamaka pa gawo losankhidwa la thupi.
Chophimba
MRI imagwiritsa ntchito ma atomu a haidrojeni kuti adziwe kusiyana pakati pa matenda osiyanasiyana m'thupi la munthu. Thupi laumunthu limapangidwa makamaka ndi ma atomu a haidrojeni (63%), zina zomwe zimafala ndi oxygen (26%), carbon (9%), nayitrogeni (1%), ndi phosphorous, calcium, ndi sodium. MRI imagwiritsira ntchito malo a atomu otchedwa "spin" kuti athe kusiyanitsa kusiyana pakati pa matenda monga minofu, mafuta, ndi tendon.
Ndi wodwala mu makina a MRI ndipo maginito akugwedezeka, nuclei ya maatomu a haidrojeni imayendera limodzi mwa njira ziwiri. Mitundu ya atomu ya haidrojeni ikhoza kusinthira kayendedwe kawo, kapena kutengera, kumbali yosiyana.
Pofuna kuyendetsa mbali ina, chophimbacho chimatulutsa mafilimu (RF) omwe amachititsa kusinthaku (nthawi zambiri mphamvu zimayenera kusintha kuti zitheke, ndipo zimatchedwa Larmour Frequency).
Chizindikiro chomwe chimagwiritsidwa ntchito popanga zithunzi za MRI chimachokera ku mphamvu yotulutsidwa ndi ma molecule omwe amasintha kapena kutengapo, kuchokera ku mphamvu zawo zapamwamba kupita kudziko lawo lamphamvu. Kusinthana kwa mphamvuyi pakati pa dziko la spin kumatchedwa resonance, motero amatchedwa magnetic resonance imaging .
Kuziyika Izo Palimodzi
Choileracho chimagwiranso ntchito kuti azindikire mphamvu zomwe amapatsidwa ndi magnetic induction kuchokera precessing ya atomu.
Kakompyuta imatembenuza deta ndikupanga zithunzi zomwe zimasonyeza maonekedwe osiyanasiyana osiyana siyana a minofu. Tikuwona izi ngati chithunzi cha mthunzi wa imvi - ziwalo zina za thupi zimawonekera mdima kapena kuwala, zonse zimadalira njira zomwe tatchulazi.
Odwala omwe akuyenera kukhala ndi MRI adzafunsidwa mafunso ena kuti aone ngati MRI ili bwino kwa wodwalayo. Zina mwa nkhani zomwe zidzakambidwe ndizo:
- Metal mu thupi
Odwala okhala ndi zitsulo m'thupi amafunika kuchenjeza antchito a MRI musanakhale ndi mayeso a MRI. Zitsulo zina zazitsulo zimagwirizana ndi MRI, kuphatikizapo mapiritsi ambiri a mitsempha . Komabe, implants ena amaletsa odwala kuti asakhale ndi MRI, monga aneurysm ziwalo mu ubongo ndi zitsulo zamaso . - Zida zopangidwa
Odwala omwe ali ndi pacemaker kapena opibrillators akuyenera kuchenjeza antchito a MRI, popeza zipangizozi zimaletsa kugwiritsa ntchito mayeso a MRI. - Zovala / Zodzikongoletsera
Zovala kapena zodzikongoletsera zilizonse ziyenera kuchotsedwa musanayambe kuphunzira za MRI.
Zinthu zamkati pafupi ndi MRI zingakhale zoopsa. Mu 2001, mwana wamwamuna wazaka zisanu ndi chimodzi anaphedwa pamene tank ya oksijeni inamenya mwanayo. Pamene magnetti a MRI anali kutsegulidwa, tank ya oksijeni inayamwa mu MRI, ndipo mwanayo anakhudzidwa ndi chinthu cholemera ichi. Chifukwa cha vutoli, antchito a MRI amasamala kwambiri pofuna kuteteza chitetezo cha odwala.
Nyimbo
Odwala nthawi zambiri amadandaula ndi phokoso la 'kumangirira' lopangidwa ndi makina a MRI. Phokoso limeneli likuchokera kumagetsi akuluakulu omwe anafotokozedwa kale. Magetsi amenewa ndi ochepa kwambiri poyerekeza ndi primary MRI magnet, koma ndi ofunika polola kusintha kosasokonekera mu maginito kuti "muwone" mbali yoyenera ya thupi.
The Space
Odwala ena ndi claustrophobic ndipo sakonda kulowa mu makina a MRI . Mwamwayi, pali njira zambiri zomwe mungapeze.
- Zovuta za MRIs
Ma MRIs atsopano sakufuna kuti mugone mkati mwa chubu. M'malo mwake, odwala okhala ndi MRI pa bondo, minofu, phazi, chigoba, kapena dzanja, akhoza kuyika gawo la thupi mkati mwa makina a MRI. Makina awa samagwira ntchito ya MRI ya mapewa, msana, chiuno, kapena pelvis. - Tsegulani MRIs
Kutsegula MRIs kunali ndi zovuta zapamwamba, komabe chitukuko cha chithunzi chinakula bwino zaka zingapo zapitazo. Ngakhale kuti MRI yotsekedwa imakondedwa ndi madokotala ambiri , MRI yotsegula ikhoza kukhala njira yabwino. - Kusintha
Odwala ena amakumana ndi vuto lokhala chete kwa mphindi 45 zomwe zimatengera kukwaniritsa MRI, makamaka phokoso lomvetsa chisoni. Choncho, zingakhale zoyenera kutenga mankhwala kuti musangalale musanakhale ndi maphunziro a MRI. Kambiranani izi ndi dokotala musanayambe kukonzekera phunziro la MRI.