Magnetic resonance

It is useful for the following:

• Tumor pathology:
• • Brain or meningeal tumors (i.e. acoustic neuroma, pituitary microadenoma, etc)
  • Special sequences: brain tractography, brain spectroscopy, brain diffusion, brain perfusion, brain angiography by means of injecting the contrast agent with an automatic syringe
  • Posterior fossa and orbital tumors
  • Metastases in cancer patients
  • Neuroectodermal tumors
• Vascular pathology:
• • Strokes
  • Congenital arteriovenous malformations
  • Venous sinuses thrombosis
• Malformation pathology:
• • Brain congenital malformations
  • Meninges congenital malformations
• Degenerative pathology:
• • Internal hydrocephalus
  • Brain atrophy
  • Epilepsy
• Inner ear pathology (inflammations, tumors, malformations)
• Orbit, eyeball, optic nerves and eyeballs muscles pathology (tumors, inflammations or neuroendocrine disorders, diplopia)
• Inflammatory pathology:
• • Encephalitis
  • Meningitis
  • Facial sinuses
  • Encephalopathy
  • Leukodystrophy
  • Demyelinating lesions or plaques (multiple sclerosis) – size, number and distribution of lesions, as well as their state of activity
• Brain pathology in systemic diseases (i.e. HIV-AIDS, lymphoma, leukemia)
• Post traumatic brain pathology:
• • CSF fistula
  • Subdural empyema
  • Brain abscess
  • Carotid cavernous fistula
  • Hygromas
  • Regional brain atrophy
• One of the main advantages is the screening for brain aneurysms in case of high risk patients:
• • With positive family history, defined as the presence of two or more first degree relatives with subarachnoid hemorrhage
  • Patients with polycystic kidney disease

Pathology:

• Degenerative, traumatic, neoplastic, post-therapeutic disease of hypopharynx, larynx, cervical trachea
• Oral cavity diseases: congenital, infectious, inflammatory
• Parathyroid space diseases
• Thyroid diseases: benign or malignant tumors, inflammatory or degenerative diseases
• Retropharyngeal space diseases
• The diagnostic of the inflammatory or infectious, tumoral (lymphomas, metastases) adenopathies

The nuclear magnetic resonance of the thorax is useful in the following cases:

• Mediastinum pathology (mediastinum tumors, cardio-vascular pathology);
• Chest wall pathology, soft tissues (i.e. invasive lung tumors in the chest wall);
• Unenhanced and contrast-enhanced thorax MRI, in patients allergic to iodine who cannot perform a contrast-enhanced thorax CT (the patient undergoes the unenhanced thorax CT for the diagnostic of the lung lesions).

The MRI investigation of the abdomen and pelvis can discover different injuries of the abdominal and pelvic organs: liver, gallbladder, pancreas, kidney, bladder, spleen, uterus and ovaries.

The investigation is useful in the following situations:

• The detection of tumors, bleedings, infections and obstructions;
• In case of women, the uterus and ovaries can be viewed;
• In case of men, the prostate can be viewed.

The recommended contrast agent is Primovist.

IThe MRI investigation of the abdomen and pelvis can reveal different injuries of the abdominal and pelvic organs: liver, gallbladder, pancreas, kidney, bladder, spleen, uterus and ovaries.

The investigation is useful in the following situations:

• The detection of tumors, bleedings, infections and obstructions;
• In case of women, the uterus and ovaries can be viewed;
• In case of men, the prostate can be viewed.

The recommended contrast agent is Primovist.

The investigation is useful in the following situations:

• Tumor pathology:
• • Nervous systems or meninges tumors (primary or secondary)
  • Intramedullary tumors (primary or secondary)
  • Extramedullary tumors (primary or secondary
• Infectious and inflammatory pathology:
• • Demyelinating lesions diagnostic
  • Spondylitis
  • Paravertebral abscess
  • Arthritis
  • Postoperative changes
• Acute spinal compression
• Cervical, thoracic or lumbar radiculopathy, without neurological signs
• Congenital or acquired syringomyelia
• Spinal canal stenosis
• Degenerative pathology: cervical disc herniation, thoracic or lumbar herniation
• Spine trauma:
• • Vertebral fractures
  • Hematoma
  • Post traumatic herniated disc
  • Spine compaction
• Malformation pathology:
• • Of the medullary cords
  • Of the meninges
• The investigation of any causes of spinal disease in pregnancy
• Prior to any vertebromedullary surgical procedures

Bone and joint segments MRI, such as – shoulder, elbow, coxofemoral joints, sacroiliac joints, knees, ankle, foot – may reveal bone or joint disorders, such as arthritis, temporomandibular joint disorders, bone marrow disorders, bone tumors, cartilage lesions, ligament and tendon ruptures or infections.

It is an important investigation for bone tumor pathology in order to assess the peri-bone tumor extension.

MRI indications in case of joint disorders:

• Menisco-ligamentous pathology;
• Cartilaginous and sub-cartilaginous pathology;
• Traumas – tendon and ligament rupture and muscle tear.

Bone and joint segments MRI, such as – shoulder, elbow, coxofemoral joints, sacroiliac joints, knees, ankle, foot – may reveal bone or joint disorders, such as arthritis, temporomandibular joint disorders, bone marrow disorders, bone tumors, cartilage lesions, ligament and tendon ruptures or infections.

It is an important investigation for bone tumor pathology in order to assess the peri-bone tumor extension.

MRI indications in case of joint disorders:

• Menisco-ligamentous pathology;
• Cartilaginous and sub-cartilaginous pathology;
• Traumas – tendon and ligament rupture and muscle tear.

The procedure is useful in the following cases:

• Bone and ligament pathology:
• • Primary or secondary bone tumors
  • Septic or aseptic osteonecrosis, osteochondritis
  • Ligament, synovial or tendon injuries of the knee, shoulder, ankle, radiocarpal joint, sacroiliac joint (ankylosing spondylitis, artrosis)
  • Traumas
• Soft tissues pathology:
• • Juvenile dermatomyositis
  • Gaucher diseases
  • Post-inflammations or post-traumatic lesions in case of children under 16

The breast magnetic resonance imaging is a noninvasive an adjuvant method to the usual diagnostic procedures, respectively mammography and breast ultrasound, which offers valuable information that cannot be obtained by any other imaging method.

This method does not replace the mammography or the breast ultrasound, but it is a complementary imaging method that has the following INDICATIONS:

• The determination of the local extension of the disease in case of patients with recently diagnosed breast cancer.
• • In case of the ispilateral breast tumor in order to view additional focal tumors, the determination of the tumor size and the chest wall invasion.
  • In case of a contralateral breast mammography in order to view the occult breast tumors.
  • It is the most useful method in case of young women (under 45) with dense breasts and in case of women with extensive intraductal component.
• In metastatic adenopathies where the primary neoplasia is unknown, following the negative results of the mammography and breast ultrasound.
• Following the initial excision of a lump of which edges were proved to be positive during the histopathology.
• The suspicion of recurrence versus scar at the surgery site due to the fact the mammography and ultrasound are not eloquent in this case. Breast MRI can determine whether the modifications are due to a normal maturity scar or to a relapse.
• Monitoring the response to neoadjuvant chemotherapy.
• The evaluation of the silicone implants integrity.
• Screening in case of patients with high risk:
• • Personal history of breast cancer.
  • Strong family history: mother or sister with breast cancer diagnosed before 50 years old; first degree relatives, including aunts and cousins diagnosed with ovarian cancer.
  • Border-line lesions (lobular carcinoma in situ, atypical cells or radial scars) in patients with a history of breast biopsy.
  • Patients known or suspected to have BRCA 1 or 2 positive.
  • Women with a history of irradiation of the mediastinum (Hodgkin disease).
• When the mammography and the ultrasound are not conclusive.
• In case of pathological nipple discharge, if the mammography, the ultrasound ± galactography are not conclusive.

Breast MRI is NOT indicated in the following cases:

• As an imaging method that replaces the mammography and the ultrasound.
• For most likely benign lesions revealed by the mammography ± ultrasound (bilateral circumscribed and multiple masses).
• In suspicious lesions revealed by the mammography ± ultrasound, the breast MRI does not exclude the biopsy.
• For the screening of the women with medium cancer risk.
• In determining the saline implant integrity.

Procedure:

• The investigation is performed between the 7th and 14th day of the menstrual cycle when the mammary gland stroma is less dense and the breast has a lower content of water.
• The patient is laid prone and her breasts are introduced in a dedicated antenna that enables the scanning without compression. This position helps to minimize the effects of the respiratory movements.
• The arms are placed over the head, and in rare cases, one of the arms is above the head and the other is stretched on the side.
• If the purpose of the investigation is to determine the integrity of the silicone implants the contrast agent shall not be administered. If the investigation is for any other purposes the intravenous contrast agent administration is needed.
• 0.1 mmol/kg of Gadolinium is intravenously injected and 5 postSDC images are obtained in 2 minutes.
• The investigation takes between 30 minutes and one hour.
• The spectroscopy, which brings additional information on the chemical substances existing in the body cells, can also be performed during the MRI examination and extends the examination with about 15 minutes.
• The interpretation of the MRI examination is performed together with the mammography ± ultrasound.

• The patient is laid supine on the MRI table with arms stretched on the sides
• Due to the TIM-Total Imaging Matrix, Siemens unique technique, the patient is equipped with dedicated antennas, for each body region: skull, cervical region, thorax, abdomen, pelvis, hip, calf -> ≈5min
• The patient is not allowed to move during the investigation => motion artifacts that lead to a false diagnostic or even to the absence of the diagnostic in some cases may occur
• In case of the segments such as thorax and abdomen, we apply successive acquisition techniques with breath holding (in apnea) ≈20-25sec => we need the full cooperation of the patient
• Stages: the unenhanced examination followed by the contrast-enhanced examination (based on Gadoliniu)
• The total acquisition time ≈ 1h30min

The advantages of the Whole Body MRI

• Enables the diagnostic of a disease without limitation to an examined anatomical region
• Enables the examination of the entire body without the reposition of the patient or the antenna to be necessary – Tim CT Oncology technology, Siemens

INDICATIONS OF WB-MRI

• The method is indicated in case of cancer patients in order to diagnose metastatic diseases – Tim CT Oncology
• In case of autoimmune diseases (i.e. Rheumatoid polyarthritis) – the detection of the asymptomatic regions with arthritis; it is indicated to use WB-MRI if there is a discrepancy between the clinical and laboratory status or if the multifocal lesions are clinically undetectable.
• In case of multifocal bone marrow diseases – histocytosis X, chronic recurrent multifocal osteomyelitis

Indications:

• Congenital heart disease
• • Segmental description of the abnormalities
  • The evaluation of the conotruncal malformations and complex abnormalities
  • Noninvasive detection and quantification of shunts, stenosis, regurgitations
  • The identification of the pulmonary venous and systemic abnormalities
• Heart or great vessels tumors – the investigation is useful in order to differentiate the cardiac and pericardial masses
• Aneurysm/dissection of the aorta
• The evaluation of the thoracic arteries and veins in order to detect their abnormalities
• The detection of morphological and anatomical heart abnormalities
• The evaluation of the cardiac function
• The evaluation of the left ventricle and some of the parameters of its activity, such as: ejection fraction, end systolic volume, end diastolic volume, the kinetics of the intraventricular septum and ventricular walls (useful in case of ventricular walls neurysmus), the evaluation of the valve kinetics
• The quantitative evaluation of the hemodynamic changes
• The investigation of the complex abnormalities
• The pre- and postoperative evaluation of the cardiac patient (by detecting the residual faults and surgical complications)

The breast spectroscopy by means of the nuclear magnetic resonance (MRI) is useful to diagnose breast cancer and to reduce false positive results and invasive biopsies.

By means of the breast spectroscopy the radiologist physician can observe the chemical composition of a lesion by measuring the level of choline compounds, the active tumor marker and to classify it in a nosological category – to establish whether the composition indicates the existence of a tumor.

In the near future the MRI spectroscopy shall be incorporated as a routine investigation for the breast examination, by significantly decreasing the number of the invasive biopsies.

The method is recommended to the women with high tumor risk, due to the fact that the MRI is more sensitive and can detect tumors that can not be revealed by other imaging methods.

Angiography types:

• Cerebral MRI angiography
• Carotid MRI angiography
• Intrathoracic great vessels MRI angiography
• Abdominal MRI angiography (renal arteries, aorta)
• Pelvis MRI angiography
• Peripheral MRI angiography

The nuclear magnetic resonance (MRI) angiography is used in order to view the blood vessels of different regions of the body: brain, cervical, chest, abdominal, pelvis, upper limbs and lower limbs region.

The nuclear magnetic resonance angiography provides information on the blood flow, can detect diseases of the veins or arteries, such as: vascular aneurysms, the presence of a blood clot on a vessel or the partial rupture of the vessel wall. The contrast agent is used in order to have a clear view of the blood vessels.

The procedure is indicated in the following situations:

• Aneurysmus or arteriovenous malformations of the brain.
• The atherosclerotic disease in the carotid arteries of the cervical region which can decrease the blood flow in the brain and can lead to a stroke (CVA), stenosis or obstruction of the carotid arteries.
• Diseases and aneurysmus of the thoracic and abdominal aorta.
• The atherosclerotic disease of the lower limbs, being helpful in preparing the patients or the endovascular surgical intervention. The MRI is limited in what concerns the view of the calcified atheromatous plaques (the CT is significantly more useful).
• Vascular kidney diseases or the determination of the blood flow for kidney transplant.
• The evaluation of the tumor vascularization for the preparation for surgery or for other treatments, such as the chemoembolization or the internal selective radiotherapy.
• The examination of the pulmonary arteries in order to detect pulmonary embolism (in case of patients allergic to iodine).

The MRI cholangiography is a non invasive method for the investigation of the biliopancreatic tract by using the nuclear magnetic resonance.

The MRI cholangiography is indicated in the following situations:

• The highlighting of the anatomic variants: pancreas – divisum or aberrant biliary ducts;
• The malformation pathology of the biliary tract, in which category the extrahepatic system is included;
• The cholangitis inflammatory pathology;
• The lithiasis pathology;
• Hypertrophic chronic pancreatitis;
•  tumoral pathology;
• The postoperative use in case of the balance of the residual lithiasis, the tumor structures or recurrences;
• In case of biliary obstruction: the level and nature of the obstacle, the upstream and downstream aspect of the biliary tract.

The Uro MRI is a noninvasive method used in order to view the entire excretory apparatus (kidneys, ureters, bladder) which enables the investigation of the following pathology of the excretory apparatus: calculi, stenosis, tumor formations or malformations, due to the high-resolution images.

Uro MRI enables the morphological and functional analysis, being superior to the urography. It is mainly used in case of the congenital hydronephrosis.

The patient needs a good hydration and previous administration of the contrast agent in order to be investigated. The Uro MRU is also useful in case of patients with iodine intolerance, in children and young patients (non-irradiating method).

Entero – MRI represents a non-irradiating alternative of tracking patients with inflammatory bowel disease in intercritical periods. This procedure requires special training within the clinic, about 1 hour before the examination.

This method is indicated for the evaluation of Crohn disease (the activity of Crohn disease, the number of intestinal loops involved in the inflammatory process, the length of the inflammatory process, lymph fistulas and abscesses). Furthermore, the Entero MRI has an important role in detecting other pathologies, such as: Meckel diverticulum, the gastrointestinal stromal tumors, the intestinal lymphoma, the neuroendocrine of the gastrointestinal tract, the primary adenocarcinoma of the small intestine, the rotation and fixation abnormalities of the gastrointestinal tract, the small intestine intussusception and polyps.

Furthermore, the Entero MRI enables the view of the bone involvement (i.e. – sacroiliac) which may be associated in some inflammatory bowel diseases or the origin of a bleeding.

This image enables the coronal and sagittal reconstructions that the surgeons may use as maps.

All this information is reliable, reproducible and simple within the surgery field.

The scanning of the prostate takes about 45-60 min and the endorectal probe is maintained only 20 de minutes. The endorectal probe is used to detect tumors, to evaluate its dimensions and to stage the tumors (extracapsular extension, the invasion of the neurovascular bundle and seminal vesicles).

The prostate spectroscopy is a method of investigating both the metabolic compositions of the tumor formations and of the normal prostate. The metabolic composition brings information on the nature of the formations (if the tumor is benign or malignant), and if the tumor is malignant the degree of the tumor aggressiveness is evaluated.

This information is useful in determining the treatment to be administered.

The diffusion is a MRI technique which is able to measure the diffusion of the water in the tissues. Its main application is the white matter imaging, where the location, orientation and anisotropy of the tract can be measured.

It is useful in locating tumors in relation to the white agent tracts (infiltration, deviation), the location of the main tracts of the white matter for the neurosurgical planning and evaluation of the white matter in degenerative brain diseases.

The technique is extremely fast in detecting the stroke, by having 100% accuracy in what concerns the diagnostic of the cerebral acute infarction.

The diffusion is a technique that will be used in the near future for the diagnostic of the metastatic lesions and is similar to the scintigraphic investigation (PET).

The method for measuring the blood volume and flow (of the capillaries) which supplies the tissues (i.e. in case of a tumor the capillary blood volume is increased).

It is useful for the planning of the biopsy – it highlights the tumor with the higher malignant potential. It is useful in the diagnostic of the stroke and the view of the “ischemic penumbra” with potential recovery of other diseases and brain disorders (tumors, schizophrenia, Alzheimer).

The investigation is also useful in the diagnostic of the myocardial ischemia, ischemic diseases of the lung, kidneys and muscles.

A new sequence in the imaging field; it evaluates and uses the magnetic properties of the blood, iron and other structures; it is used in order to detect the cerebral microbleeds, cavernomas, venous angiomas, arteriovenous malformations and low-flow venous abnormalities, brain trauma, vascular dementia, tumor vascularization, epilepsy, calcium differentiation, Stuge Weber disease, mineralization, bleeding and iron deposits in the nucleus basalis.

It is the MRI technique capable of measuring the water restrictions in the tissues; the main application is in the imaging of the white matter where the localization, orientation and anisotropy of the tracts can be measured; the architecture of the white matter tracts facilitates the diffusion of the water molecules along their main path; DTI applications are useful in locating tumors in relation to the white matter tracts (infiltration, deviation), the locating of the white matter tracts for the neurosurgical planning and evaluation of the white matter in degenerative brain diseases.

Fetal MRI is a nuclear magnetic resonance investigation performed to a fetus, in addition to a normal ultrasound investigation.

Fetal MRI is useful in evaluating the development stage of the fetus, enables a better differentiation and characterization of the fetal anatomical structures without being influenced by several particular conditions, such as the low quantity of amniotic fluid. A distinct advantage is represented by the precise and detailed view of the fetal brain and spinal cord. Furthermore, it provides important information on the mother’s abdomen.

Fetal MRI is indicated when there are revealed pathological changes in ultrasound, such as hydrocephalus (ventricular dilatation), anatomic abnormalities of the brain, bowel dilatation, diaphragmatic hernia, kidney damage, etc.

The fetal MRI is mostly indicated in the brain examination (because the ultrasound is limited in what concerns brain exploration). Fetal MRI is indicated for the thoracic and abdominal pathology, for the examination of the spine and less for the fetal bone pathology. Fetal MRI plays an important role in determining the subsequent therapeutic strategy.

In case of the fetal MRI, the special preparation of the mother, the fetus sedation or the contrast agent is not necessary. The investigation is not dangerous for the fetus or the mother.

Fetal MRI has been performed for 20 years and no risks were known in what concerns the mother or the fetus.