RESUMO
This review describes targeted magnetic resonance imaging (tMRI) of small changes in the T1 and the spatial properties of normal or near normal appearing white or gray matter in disease of the brain. It employs divided subtracted inversion recovery (dSIR) and divided reverse subtracted inversion recovery (drSIR) sequences to increase the contrast produced by small changes in T1 by up to 15 times compared to conventional T1-weighted inversion recovery (IR) sequences such as magnetization prepared-rapid acquisition gradient echo (MP-RAGE). This increase in contrast can be used to reveal disease with only small changes in T1 in normal appearing white or gray matter that is not apparent on conventional MP-RAGE, T2-weighted spin echo (T2-wSE) and/or fluid attenuated inversion recovery (T2-FLAIR) images. The small changes in T1 or T2 in disease are insufficient to produce useful contrast with conventional sequences. To produce high contrast dSIR and drSIR sequences typically need to be targeted for the nulling TI of normal white or gray matter, as well as for the sign and size of the change in T1 in these tissues in disease. The dSIR sequence also shows high signal boundaries between white and gray matter. dSIR and drSIR are essentially T1 maps. There is a nearly linear relationship between signal and T1 in the middle domain (mD) of the two sequences which includes T1s between the nulling T1s of the two acquired IR sequences. The drSIR sequence is also very sensitive to reductions in T1 produced by Gadolinium based contrast agents (GBCAs), and when used with rigid body registration to align three-dimensional (3D) isotropic pre and post GBCA images may be of considerable value in showing subtle GBCA enhancement. In serial MRI studies performed at different times, the high signal boundaries generated by dSIR and drSIR sequences can be used with rigid body registration of 3D isotropic images to demonstrate contrast arising from small changes in T1 (without or with GBCA enhancement) as well as small changes in the spatial properties of normal tissues and lesions, such as their site, shape, size and surface. Applications of the sequences in cases of multiple sclerosis (MS) and methamphetamine dependency are illustrated. Using targeted narrow mD dSIR sequences, widespread abnormalities were seen in areas of normal appearing white matter shown with conventional T2-wSE and T2-FLAIR sequences. Understanding of the features of dSIR and drSIR images is facilitated by the use of their T1-bipolar filters; to explain their targeting, signal, contrast, boundaries, T1 mapping and GBCA enhancement. Targeted MRI (tMRI) using dSIR and drSIR sequences may substantially improve clinical MRI of the brain by providing unequivocal demonstration of abnormalities that are not seen with conventional sequences.
RESUMO
Abnormal activation of the extrasynaptic N-methyl-d-aspartate receptor (NMDAR) contributes to the pathogenesis of Alzheimer's disease (AD). Ceftriaxone (Cef) can improve cognitive impairment by upregulating glutamate transporter-1 and promoting the glutamate-glutamine cycle in an AD mouse model. This study aimed to investigate the effects of Cef on synaptic plasticity and cognitive-behavioral impairment and to unravel the associated underlying mechanisms. We used an APPswe/PS1dE9 (APP/PS1) mouse model of AD in this study. Extrasynaptic components from hippocampal tissue homogenates were isolated using density gradient centrifugation. Western blot was performed to evaluate the expressions of extrasynaptic NMDAR and its downstream elements. Intracerebroventricular injections of adeno-associated virus (AAV)-striatal enriched tyrosine phosphatase 61 (STEP61 ) and AAV-STEP61 -shRNA were used to modulate the expressions of STEP61 and extrasynaptic NMDAR. Long-term potentiation (LTP) and Morris water maze (MWM) tests were performed to evaluate the synaptic plasticity and cognitive function. The results showed that the expressions of GluN2B and GluN2BTyr1472 in the extrasynaptic fraction were upregulated in AD mice. Cef treatment effectively prevented the upregulation of GluN2B and GluN2BTyr1472 expressions. It also prevented changes in the downstream signals of extrasynaptic NMDAR, including increased expressions of m-calpain and phosphorylated p38 MAPK in AD mice. Furthermore, STEP61 upregulation enhanced, whereas STEP61 downregulation reduced the Cef-induced inhibition of the expressions of GluN2B, GluN2BTyr1472 , and p38 MAPK in the AD mice. Similarly, STEP61 modulation affected Cef-induced improvements in induction of LTP and performance in MWM tests. In conclusion, Cef improved synaptic plasticity and cognitive behavioral impairment in APP/PS1 AD mice by inhibiting the overactivation of extrasynaptic NMDAR and STEP61 cleavage due to extrasynaptic NMDAR activation.
Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Ceftriaxona/farmacologia , Ceftriaxona/uso terapêutico , Modelos Animais de Doenças , Plasticidade Neuronal/fisiologia , Cognição , Camundongos Transgênicos , Receptores de N-Metil-D-Aspartato/metabolismoRESUMO
This paper updates and extends three previous papers on tissue property filters (TP-filters), Multiplied, Added, Divided and/or Subtracted Inversion Recovery (MASTIR) pulse sequences and synergistic contrast MRI (scMRI). It does this by firstly adding the central contrast theorem (CCT) to TP-filters, secondly including division with MASTIR sequences to make them Multiplied, Added, Subtracted and/or Divided IR (MASDIR) sequences, and thirdly incorporating division into the image processing needed for scMR to increase synergistic T1 contrast. These updated concepts are then used to explain and improve contrast at tissue boundaries, as well as to develop imaging regimes to detect and monitor small changes to the brain over time and quantify T1. The CCT is in two parts: the first part states that contrast produced by each TP is the product of the change in TP multiplied by the TP sequence weighting which is the first partial derivative of the TP-filter. The second part states that the overall fractional contrast is the algebraic sum of the fractional contrasts produced by each of the TPs. Subtraction of two IR sequences alone about doubles contrast relative to a conventional single IR sequence. Division of this subtraction can amplify contrast 5-15 times compared with conventional IR sequences. Dividing sequences can be problematic in areas where the signal is zero but this is avoided by dividing the difference in signal of two magnitude reconstructed IR sequences by the sum of their signals. The basis for the production of high contrast, high spatial resolution boundaries at white-gray matter junctions, between cerebral cortex and cerebrospinal fluid (CSF) and at other sites with subtracted IR (SIR) and divided subtracted IR (dSIR) sequences is explained and examples are shown. A key concept is the tissue fraction f, which is the proportion of a tissue in a mixture of two tissues within a voxel. Contrast at boundaries is a function of the partial derivative of the TP-filter, the partial derivative of the relevant TP with respect to f, and the partial derivative of f with respect to distance, x. Location of tissue boundaries is important for segmentation and is helpful in determining if inversion times have been chosen correctly. In small change regimes, the high sensitivity to small changes in T1 provided by dSIR images, together with the high definition boundaries, afford mechanisms for detecting small changes due to contrast agents, disease, perfusion and other causes. 3D isotropic rigid body registration provides a technique for following these changes over time in serial studies. Images showing high lesion contrast, high definition tissue and fluid boundaries, and the detection of small changes are included. T1 maps can be created by linearly scaling dSIR images.
RESUMO
BACKGROUND: T1ρ has been extensively reported as a sensitive biomarker of biochemical changes in the nucleus pulposus (NP) and annulus fibrosis of intervertebral discs (IVDs). However, no T1ρ study of cartilaginous endplates (CEPs) has yet been reported because the relatively long echo times (TEs) of conventional clinical T1ρ sequences cannot effectively capture the fast-decaying magnetic resonance signals of CEPs, which have very short T2/T2*s. This can be overcome by using ultrashort echo time (UTE) T1ρ acquisitions. METHODS: Seventeen subjects underwent UTE with adiabatic T1ρ preparation (UTE-Adiab-T1ρ) and T2-weighted fast spin echo imaging of their lumbar spines. Each IVD was manually segmented into seven regions (i.e., outer anterior annulus fibrosis, inner anterior annulus fibrosis, outer posterior annulus fibrosis, inner posterior annulus fibrosis, superior CEP, inferior CEP, and NP). T1ρ values of these sub-regions were correlated with IVD modified Pfirrmann grades and subjects' ages. In addition, T1ρ values were compared in subjects with and without low back pain (LBP). RESULTS: Correlations of T1ρ values of the outer posterior annulus fibrosis, superior CEP, inferior CEP, and NP with modified Pfirrmann grades were significant (P<0.05) with R values of 0.51, 0.36, 0.38, and -0.94, respectively. Correlations of T1ρ values of the outer anterior annulus fibrosis, outer posterior annulus fibrosis, and NP with ages were significant with R equal to 0.52, 0.71, and -0.76, respectively. T1ρ differences of the outer posterior annulus fibrosis, inferior CEP, and NP between the subjects with and without LBP were significant (P=0.005, 0.020, and 0.000, respectively). CONCLUSIONS: The UTE-Adiab-T1ρ sequence can quantify T1ρ of whole IVDs including CEPs. This is an advance, and of value for comprehensive assessment of IVD degeneration.
RESUMO
It is difficult to repair large skull and dural defects. We observed the therapeutic effects of anterolateral thigh flaps with vascular fascia lata for repairing large skull and dural defects.From December 2008 to June 2019, we repaired large skull and dural defects for 28 cases including 12 cases with scalp malignant tumor and 16 cases requiring removal of titanium mesh which had been once placed due to craniocerebral trauma. The scalp malignant tumor invaded full-thickness skull in 12 cases; and invaded cervical lymph nodes, dura mater or brain tissue in 3 cases. In the 12 cases with scalp malignant tumor, the scalp defects of 12âcmâ×â9âcm to 22âcmâ×â18âcm and skull defects of 9 cmâ×â7 cm to 15 cmâ×â12âcm after radical tumor resection were repaired using anterolateral thigh flaps of 14 cmâ×â11 cm to 23 cmâ×â19âcm with fascia lata of 10 cmâ×â8âcm to 16 cmâ×â12âcm. Postoperative radiotherapy and chemotherapy were also performed in the 3 cases with tumor metastasis. In the 16 cases requiring removal of titanium mesh, the skull and dural defects of 8 cmâ×â7 cm to 15 cmâ×â11âcm after removal of titanium mesh were repaired using anterolateral thigh flaps of 10 cmâ×â8 cm to 16 cmâ×â12âcm.In all cases, the transplanted anterolateral thigh flap with fascia lata survived after surgery and no vascular crisis occurred. During the followup of 8 months to 9 years, the flap appearance in the head-repaired area was fine, no external hernia of brain tissue occurred, the appearance of the femoral donor site was acceptable, and femoral muscle strength and movements were normal in all cases. The 12 cases with scalp malignant tumor had no local recurrence or distant metastasis.Repairing the skull and dural defects caused by radical surgery for scalp malignant tumor or removal of titanium mesh using anterolateral thigh flaps with vascular fascia lata, is effective. The appearance in the head-repaired area is fine without external hernia of brain tissue.
Assuntos
Dura-Máter/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Crânio/cirurgia , Retalhos Cirúrgicos/transplante , Coxa da Perna/cirurgia , Adulto , Idoso , Lesões Encefálicas/cirurgia , Carcinoma Basocelular/cirurgia , Carcinoma de Células Escamosas/cirurgia , Dura-Máter/lesões , Feminino , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Couro Cabeludo/cirurgia , Neoplasias Cutâneas/cirurgia , Crânio/lesões , Telas Cirúrgicas , Titânio , Adulto JovemRESUMO
This paper reviews magnetic resonance (MR) pulse sequences in which the same or different tissue properties (TPs) such as T1 and T2 are used to contribute synergistically to lesion contrast. It also shows how synergistic contrast can be created with Multiplied, Added, Subtracted and/or fiTted Inversion Recovery (MASTIR) sequences, and be used to improve the sensitivity, specificity and scope of clinical magnetic resonance imaging (MRI) protocols. Synergistic contrast can be created from: (i) the same TP, e.g., T1 used twice or more in a pulse sequence; (ii) different TPs such as ρm, T1, T2, and D* used once or more within a sequence, and (iii) additional suppression or reduction of signals from tissues and/or fluids such as fat, long T2 tissues and cerebrospinal fluid (CSF). The short inversion time (TI) inversion recovery (IR) (STIR) and double IR (DIR) sequences usually show synergistic positive contrast for lesions which have increases in both T1 and T2. The diffusion weighted pulsed gradient spin echo (PGSE) sequence shows synergistic contrast for lesions which have an increase in T2 and a decrease in D*; the sequence is both positively weighted for T2 and negatively weighted for D*. In the brain, when an IR sequence nulling white matter has subtracted from it an IR sequence nulling gray matter to form the subtracted IR (SIR) sequence, increases in the single TP T1 between the two nulling points of the original two sequences generate high synergistic positive contrast. In addition, the subtraction to produce the SIR sequence reduces fat and CSF signals. To provide high sensitivity to changes in TPs in disease the SIR sequence can be used (i) alone to provide synergistic T1 contrast as above; (ii) with T2-weighting to provide synergistic T1 and T2 contrast, and (iii) with T2- and D*-weighting to provide synergistic T1, T2, and D* contrast. The SIR sequence can also be used in reversed form (longer TI form minus shorter TI form) to produce very high positive synergistic T1 contrast for reductions in T1, and so increase the positive contrast enhancement produced by clinical gadolinium-based contrast agents (GBCAs) when they reduce T1. The specificity of MRI examinations can be improved by using the reversed SIR sequence with a long echo time (TE) gradient echo as well as echo subtraction to show synergistic high contrast from T1 and T2* shortening produced by organic iron. Other added and subtracted forms of the MASTIR sequence can be used synergistically to selectively show myelin, myelin water and fluids including blood and CSF. Protocols using MASTIR sequences to provide synergistic contrast in MRI of the brain, prostate and articular cartilage are included as illustrative examples, and the features of synergistic contrast MRI (scMRI) are compared to those of multiparametric MRI (mpMRI) and functional MRI (fMRI).
RESUMO
PURPOSE: To evaluate the 3-dimensional (3D) zero echo time (ZTE) magnetic resonance imaging (MRI) technique and compare it with 3D computed tomography (CT) for the assessment of the glenoid bone. METHODS: ZTE MRI using multiple resolutions and multislice CT were performed in 6 shoulder specimens before and after creation of glenoid defects and in 10 glenohumeral instability patients. Two musculoskeletal radiologists independently generated 3D volume-rendered images of the glenoid en face. Post-processing times and glenoid widths were measured. Inter-modality and inter-rater agreement was assessed. RESULTS: Intraclass correlation coefficients (ICCs) for inter-modality assessment showed almost perfect agreement for both readers, ranging from 0.949 to 0.991 for the ex vivo study and from 0.955 to 0.987 for the in vivo patients. Excellent interobserver agreement was found for both the ex vivo (ICCs ≥ 0.98) and in vivo (ICCs ≥ 0.92) studies. For the ex vivo study, Bland-Altman analyses for CT versus MRI showed a mean difference of 0.6 to 1 mm at 1.0-mm3 MRI resolution, 0.3 to 0.6 mm at 0.8-mm3 MRI resolution, and 0.3 to 0.6 mm at 0.6-mm3 MRI resolution for both readers. For the in vivo study, Bland-Altman analyses for CT versus MRI showed a mean difference of 0.6 to 0.8 mm at 1.0-mm3 MRI resolution, 0.5 to 0.6 mm at 0.8-mm3 MRI resolution, and 0.4 to 0.8 mm at 0.7-mm3 MRI resolution for both readers. Mean post-processing times to generate 3D images of the glenoid ranged from 32 to 46 seconds for CT and from 33 to 64 seconds for ZTE MRI. CONCLUSIONS: Three-dimensional ZTE MRI can potentially be considered as a technique to determine glenoid width and can be readily incorporated into the clinical workflow. LEVEL OF EVIDENCE: Level II, development of diagnostic criteria (consecutive patients with consistently applied reference standard and blinding).
Assuntos
Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada Multidetectores/métodos , Escápula/diagnóstico por imagem , Articulação do Ombro/diagnóstico por imagem , Adulto , Osso e Ossos/patologia , Cadáver , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Articulação do Ombro/patologia , Adulto JovemRESUMO
The group of Multiplied, Added, Subtracted and/or fiTted Inversion Recovery (MASTIR) pulse sequences in which usually two or more inversion recovery (IR) images of different types are combined is described, and uses for this type of sequence are outlined. IR sequences of different types can be multiplied, added, subtracted, and/or fitted together to produce variants of the MASTIR sequence. The sequences provide a range of options for increasing image contrast, demonstrating specific tissues and fluids of interest, and suppressing unwanted signals. A formalism using the concept of pulse sequences as tissue property filters is used to explain the signal, contrast and weighting of the pulse sequences with both univariate and multivariate filter models. Subtraction of one magnitude reconstructed IR image from another with a shorter TI can produce very high T1 dependent positive contrast from small increases in T1. The reverse subtracted IR sequence can provide high positive contrast enhancement with gadolinium chelates and iron deposition which decrease T1. Additional contrast to that arising from increases in T1 can be produced by supplementing this with contrast arising from concurrent increases in ρm and T2, as well as increases or decreases in diffusion using subtraction IR with echo subtraction and/or diffusion subtraction. Phase images may show 180º differences as a result of rotating into the transverse plane both positive and negative longitudinal magnetization. Phase images with contrast arising in this way, or other ways, can be multiplied by magnitude IR images to increase the contrast of the latter. Magnetization Transfer (MT) and susceptibility can be used with IR sequences to improve contrast. Selective images of white and brown adipose tissue lipid and water components can be produced using different TIs and in and out-of-phase TEs. Selective images of ultrashort and short T2 tissue components can be produced by nulling long T2 tissue components with an inversion pulse and subtraction of images with longer TEs from images with ultrashort TEs. The Double Echo Sliding IR (DESIRE) sequence provides images with a wide range of TIs from which it is possible to choose values of TI to achieve particular types of tissue and/or fluid contrast (e.g., for subtraction with different TIs, as described above, and for long T2 tissue signal nulling with UTE sequences). Unwanted tissue and fluid signals can be suppressed by addition and subtraction of phase-sensitive (ps) and magnitude reconstructed images. The sequence also offers options for synergistic use of the changes in blood and tissue ρm, T1, T2/T2*, D* and perfusion that can be seen with fMRI of the brain. In-vivo and ex-vivo illustrative examples of normal brain, cartilage, multiple sclerosis, Alzheimer's disease, and peripheral nerve imaged with different forms of the MASTIR sequence are included.
RESUMO
BACKGROUND: Degradation of cartilage and meniscus may be mediated by changes in extracellular pH. The purpose of this study was to optimize saturation powers used with the acidoCEST magnetic resonance imaging (MRI) technique with a 3D ultrashort echo time readout (acidoCEST-UTE) and to demonstrate feasibility of the method for measuring pH in cartilage and meniscus in vivo. METHODS: Magnetization transfer ratio asymmetry and ratio of radiofrequency (RF) power mismatch at different powers were evaluated in cartilage and meniscus tissue phantoms for iopamidol and iohexol. Using optimized RF powers, the acidoCEST-UTE MRI sequence was used to assess pH of joint fluid and tissues in four patients after direct intra-articular administration of iodinated contrast. RESULTS: In the phantoms, the ratio of powers 0.54/1.10 µT showed the strongest correlation with pH. In vivo acidoCEST-UTE pH measurements of intra-articular fluid were similar to electrode measurements of the contrast agent (7.22 vs. 7.1 for iopamidol, respectively; 7.65 vs. 7.5 for iohexol, respectively). As measured with the acidoCEST-UTE technique, overall mean cartilage pH was significantly lower than overall mean meniscus pH (6.60 vs. 6.72, respectively; P=0.043). CONCLUSIONS: AcidoCEST-UTE MRI after direct intra-articular administration of either iopamidol or iohexol can be used to measure cartilage and meniscus pH in vivo.
RESUMO
Objective: To develop a physical- cognitive scale for assessment of frailty and compare the clinical features between the new scale and the conventional Fried criteria. Methods: 1757 individuals aged 70-84 were analyzed. Participants reporting three or more Fried phenotypes were grouped as frail patients (FP) whereas others as non-frail (NF). A score of Hasegawa's dementia scale (HDS-R) higher than 21.5 were classified as non-cognitive impairment group (NCI) group. By combining the cognitive and frailty criteria, participants manifesting three or more positive components out of the six were categorized into the Physical-cognitive frailty group (Pc-F) while others into non- Pc-F (Pc-NF). Results: Of all the participants, 46.7% (820) were males and 53.3% (937) were females. The mean age was 75.33 ± 3.90. 10.1% (178/1757) were evaluated as FP patients. The prevalence of CI was 53.2%; CI was much higher in the frail group (77.0%) than in the non-frail group (50.5%). Based on the new Pc-F scale, 163 out of 1579 NF participants were identified as Pc-F, and the prevalence of Pc-F reached 19.4% (341/1757). In the Pc-F group, there are more females, patients of advanced age, diabetes, stroke, CHD, CKD, metabolic syndrome, and high hs-CRP. Within the Pc-F group, patients with CI showed a higher incidence of exhaustion, low activity, weakness, and slowness than those without CI. Conclusions: Our study revealed a significantly worse status in frail participants with CI than without. Our new scale shows a stronger correlation between frailty and complications than the classic phenotype.
Assuntos
Disfunção Cognitiva/diagnóstico , Fragilidade/diagnóstico , Inquéritos e Questionários , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , China , Disfunção Cognitiva/complicações , Feminino , Idoso Fragilizado , Fragilidade/complicações , Indicadores Básicos de Saúde , Humanos , Masculino , Escalas de Graduação PsiquiátricaRESUMO
It is difficult to repair knee deep burn wounds in elderly patients. In this study, we observed the therapeutic effects of descending genicular artery-saphenous artery perforator flaps on knee deep burn wounds in elderly patients.Between December 2013 and February 2018, we repaired knee third-degree burn wounds using descending genicular artery-saphenous artery perforator flaps of 20â×â12âcm to 23â×â13âcm in 56 elderly patients. For the patella and patellar ligament with complete necrosis, the patella and patellar ligament were completely removed, whereas for the patella and patellar ligament with partial necrosis, necrotic parts were removed first. The donor area was repaired using intermediate thickness free skin graft. The 56 patients were 76- to 85 years' old and all had unilateral knee burn.All flaps survived in the 56 patients. After the follow-up of 2 to 36 months, the flaps were excellent in texture and appearance, and exhibited sensory recovery. In the 8 patients with completely necrotic patella and patellar ligament as well as open knee joint, the weight-bearing function of knee joint was retained, which met patients' requirements of limb salvage and weight-bearing function. In the other 48 patients with partially necrotic patella and patellar ligament as well as open joint capsule, the postoperative flexion and extension of the knee joint were good.In elderly patients, it is an effective method to repair knee deep burn wounds using the descending genicular artery-saphenous artery perforator flaps.
Assuntos
Queimaduras/cirurgia , Traumatismos do Joelho/cirurgia , Retalho Perfurante , Procedimentos de Cirurgia Plástica/métodos , Transplante de Pele/métodos , Idoso , Idoso de 80 Anos ou mais , Queimaduras/patologia , Feminino , Artéria Femoral , Humanos , Joelho/cirurgia , Traumatismos do Joelho/patologia , Masculino , Necrose , Patela/cirurgia , Ligamento Patelar/cirurgia , Retalho Perfurante/irrigação sanguínea , Estudos Retrospectivos , Veia Safena , Resultado do TratamentoRESUMO
OBJECTIVE: Currently, magnetic resonance imaging (MRI) is the most commonly used imaging modality for observing the growth and development of mesenchymal stem cells (MSCs) after in vivo transplantation to treat osteoarthritis (OA). However, it is a challenge to accurately monitor the treatment effects of MSCs in the zone of calcified cartilage (ZCC) with OA. This is especially true in the physiological and biochemical views that are not accurately detected by MRI contrast agents. In contrast, ultrashort time echo (UTE) MRI has been shown to be sensitive to the presence of the ZCC, creating the potential for more effectively observing the repair of the ZCC in OA by MSCs. A special focus is given to the outlook of the use of UTE MRI to detect repair of the ZCC with OA through MSCs. The limitations of the current techniques for clinical applications and future directions are also discussed. DATA SOURCES: Using the combined keywords: "osteoarthritis", "mesenchymal stem cells", "calcified cartilage", and "magnetic resonance imaging", the PubMed/MEDLINE literature search was conducted up to June 1, 2017. STUDY SELECTION: A total of 132 published articles were initially identified citations. Of the 132 articles, 48 articles were selected after further detailed review. This study referred to all the important English literature in full. RESULTS: In contrast, UTE MRI has been shown to be sensitive to the presence of the ZCC, creating the potential for more effectively observing the repair of the ZCC in OA by MSCs. CONCLUSIONS: The current studies showed that the ZCC could be described in terms of its histomorphology and biochemistry by UTE MRI. We prospected that UTE MRI has been shown the potential for more effectively observing the repair of the ZCC in OA by MSCs in vivo.
Assuntos
Imageamento por Ressonância Magnética/métodos , Osteoartrite/diagnóstico por imagem , Osteoartrite/terapia , Cartilagem Articular/diagnóstico por imagem , Humanos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologiaRESUMO
OBJECTIVE: To observe the clinical effects of repair of complicated tissue defects of several body parts with composite anterolateral femoral fascia lata perforator tissue flaps (fascial flap or fascial skin flap) with the aid of micro-surgery. METHODS: From February 2008 to August 2012, complicated tissue defects in 12 patients were repaired with composite anterolateral femoral fascia lata perforator tissue flaps. Two of the 12 patients suffered from a defect of scalp, skull, and dura mater as a result of resection of a malignant tumor of the scalp; 3 patients showed a defect of skin and tendo calcaneus in the heel and lower leg; 2 patients showed a defect of skin and extensor tendon in the dorsum of hands; the other 5 patients suffered from defects of skin and extensor tendon in the foot and ankle combined with exposure of bone or internal buttress plate. The size of tissue flaps ranged from 12 cm ×6 cm to 19 cm ×18 cm. The donor sites were closed by immediate suturing or skin grafting. RESULTS: All 12 tissue flaps survived. Patients were followed up for 2 to 36 months. The flaps were shown to have good appearance, texture and function. Two patients with the defect of the scalp, skull and dura mater after a resection of the malignant tumor of the scalp did not have recurrence or herniation of brain tissue. The foot-raising function in 3 patients with the defect of skin and tendo calcaneus in the heel and lower leg was recovered, and according to Arner-Lindholm criteria the result was excellent in 2 cases and good in 1 case. The extension function of fingers of 2 patients with defects of skin and extensor tendon in the dorsum of hands was good according to the evaluation criteria of Chinese Medical Association Society of Hand Surgery for tendon repair of hand. The extension function of toes of 5 patients with defects of skin and extensor tendon in the foot and ankle combined with exposure of bone or internal buttress plate was recovered and improved. CONCLUSIONS: Transplantation of composite anterolateral femoral fascia lata perforator tissue flaps with the aid of micro-surgery is an effective method in repairing the tissue defects of skull, dura mater, and the extensor tendon of hands or feet, with restoration of the extension function.