Predictive role of post-treatment [18F]FDG PET/CT in patients with uterine cervical cancer

Objective

To evaluate the efficacy of post-treatment positron emission tomography (PET)/computed tomography (CT) for identification of tumor recurrence, and to determine whether [¹⁸F]fluorodeoxyglucose (FDG) uptake measured as the maximum standardized uptake value (SUV_max) has predictive role regarding survival in patients with uterine cervical cancer.

Methods

Medical records from 276 women with uterine cervical cancer who had post-treatment [¹⁸F]FDG PET/CT performed were retrospectively reviewed. Results of PET/CT scans were compared with histological or clinical examination.

Results

Ninety-five (34.4%) of the 276 patients had documented recurrence by either surgical biopsy or clinical and imaging follow-up. Median duration from treatment to PET/CT scan was 24 months (range, 6–307). The overall sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of post-treatment PET/CT were 94.7%, 87.8%, 80.4%, 97%, and 90.2%, respectively. The PET/CT scan modified both the diagnostic or treatment plan in 67 patients (24.3%). Patients were divided into two groups according to cut-off SUV_max established on the basis of ROC analysis (<5.25 vs. ≥5.25), and there was a significant difference in OS between groups (p = 0.001). In addition, the 5-year progression-free survival (PFS) and OS rates of patients with a negative PET/CT scan for recurrence were significantly better than those with a positive PET/CT (98.62% vs. 17.83%, p < 0.0001 for PFS, 99.31% vs. 85.38%, p = 0.0015 for OS).

Conclusion

Post-treatment PET/CT scan is a sensitive and accurate surveillance modality, and provides prognostic information in uterine cervical cancer. Furthermore, it may allow individualization of patient care.     

Placenta accreta in women with prior uterine surgery: Diagnostic accuracy of Doppler ultrasonography and MRI

Aim

To test and compare the sensitivity and accuracy of color Doppler and MRI in prenatal diagnosis of placenta accreta (PA) in gravid uterus with prior surgery.

Patients and methods

Twenty eight gravid women with prior uterine surgery and abnormal placental position were collected after meeting the inclusion criteria depending on gray scale sonographic findings which suggested placenta accreta. Color Doppler and MRI findings were classified as positive and negative according to presence or absence of imaging criteria of placenta accreta. The sensitivity and accuracy of color Doppler and MR imaging were compared.

Results

The surgical and pathological reports of our patients confirmed placenta accreta in 11/28 (39%) patients. According to color Doppler 15/28 (53%) patients were positive and 13/28 (46%) were negative for placenta accreta with sensitivity 90%, accuracy 78%, and specificity 70%. According to MRI findings 14/28 (50%) patients were positive for placenta accreta and 14/28(50%) were negative, with sensitivity 90%, accuracy 82%, and specificity 77%.

Conclusion

Color Doppler and MRI were useful in the diagnosis of placenta accreta with the same sensitivity and positive impact on the peripartum clinical management.     

Correlation between tumor size and surveillance of lymph node metastasis for IB and IIA cervical cancer by magnetic resonance images

Purpose

To assess the feasibility of preoperative MRI based measurement of tumor size with regard to lymph node (LN) metastasis in early uterine cervical cancer.

Material and Methods

A retrospective review of patients with FIGO stage IB–IIA cervical cancer who underwent lymphadenectomy was performed. Diagnostic accuracy of MRI in detecting LN metastasis and rate of LN recurrence in terms of tumor size (≤4 cm versus >4 cm) were analyzed. ROC curve analysis was used to determine LN size for differentiating LN metastasis in terms of tumor size. P < 0.05 was considered statistically significant.

Results

Of the 200 patients, 45 (22.3%) had LN metastasis. There was no statistical difference between patients-based and region-specific analysis. The patients with tumor size with >4 cm revealed higher diagnostic accuracy of MRI in detecting LN metastasis (85.4% versus 50.6%, P = 0.023) and rate of LN recurrence (20.0% versus 6.4%, P = 0.031) in than those with size with ≤4 cm, the differences were statistically significant. Discriminant analysis of LN size for the differentiation of metastasis from non-metastasis resulted in cut-off values (11.8 mm; size with >4 cm versus 8.3 mm; size with ≤4 cm) and diagnostic accuracy (84.0% of size with >4 cm versus 72.0% of size with ≤4 cm).

Conclusion

MRI has limited sensitivity, but high specificity in predicting surveillance of LN metastasis in the preoperative early cervical cancer, especially useful tool for patients with tumor size with >4 cm.     

The role of magnetic resonance imaging in determining the proximal extension of early stage cervical cancer to the internal os

Purpose

To study the interobserver variability of MRI for visualization of the internal os and measuring the distance between tumor and the internal os in patients with early cervical carcinoma and to compare the distance between tumor and the internal os measured on MRI with invasion of the internal os determined by histopathology.

Materials and methods

All T2-weighed MRI examinations between January 2003 and December 2007 of patients who underwent hysterectomy, of ≤40 years, with clinical stage IB1 cervix carcinoma and tumor size ≤2 cm were retrieved. 27 patients fulfilled these criteria.Two radiologists retrospectively reviewed the images for visualization of the internal os and the distance between tumor and the internal os; agreement and intraclass correlation coefficients (ICCs) were calculated to determine interobserver variability. The distance between tumor and the internal os measured on MRI was compared with invasion of the internal os determined by histopathology.

Results

In 26 patients, visualization of the internal was rated as good or moderate by both radiologists (agreement 96%). In 15 patients, both radiologists observed a tumor and the ICC for the distance between tumor and the internal os was 0.752 (95%CI: 0.406-0.909). Assuming 5 mm distance between tumor and the internal os on MRI as criterion for invasion of the internal os, 1 true-positive, 2 false-positives and none false-negatives were observed. Assuming 1 cm as criterion increases the number of false-positives, respectively 3 and 5 by radiologist 1 and radiologist 2.

Conclusion

MRI has high interobserver values for visualization of the internal os and no false-negatives for involvement of the internal os.     

MR imaging features and staging of neuroendocrine carcinomas of the uterine cervix with pathological correlations

Objective

To determine MR imaging features and staging accuracy of neuroendocrine carcinomas (NECs) of the uterine cervix with pathological correlations.

Methods

Twenty-six patients with histologically proven NECs, 60 patients with squamous cell carcinomas (SCCs), and 30 patients with adenocarcinomas of the uterine cervix were included. The clinical data, pathological findings, and MRI findings were reviewed retrospectively. MRI features of cervical NECs, SCCs, and adenocarcinomas were compared, and MRI staging of cervical NECs was compared with the pathological staging.

Results

Cervical NECs showed a higher tendency toward a homogeneous signal intensity on T2-weighted imaging and a homogeneous enhancement pattern, as well as a lower ADC value of tumour and a higher incidence of lymphadenopathy, compared with SCCs and adenocarcinomas (P?<?0.05). An ADC value cutoff of 0.90?×?10^-3 mm²/s was robust for differentiation between cervical NECs and other cervical cancers, with a sensitivity of 63.3 % and a specificity of 95 %. In 21 patients who underwent radical hysterectomy and lymphadenectomy, the overall accuracy of tumour staging by MR imaging was 85.7 % with reference to pathology staging.

Conclusion

Homogeneous lesion texture and low ADC value are likely suggestive features of cervical NECs and MR imaging is reliable for the staging of cervical NECs.

Key Points

? Cervical NECs show a tendency of lesion homogeneity and lymphadenopathy ? Low ADC values are found in cervical NECs ? MRI is an accurate imaging modality for the cervical NEC staging

     

FDG PET/MR for lymph node staging in head and neck cancer

Objective

To assess the diagnostic value of PET/MR (positron emission tomography/magnetic resonance imaging) with FDG (18F-fluorodeoxyglucose) for lymph node staging in head and neck cancer.

Materials and methods

This prospective study was approved by the local ethics committee; all patients signed informed consent. Thirty-eight patients with squamous cell carcinoma of the head and neck region underwent a PET scan on a conventional scanner and a subsequent PET/MR on a whole-body hybrid system after a single intravenous injection of FDG. The accuracy of PET, MR and PET/MR for lymph node metastases were compared using receiver operating characteristic (ROC) analysis. Histology served as the reference standard.

Results

Metastatic disease was confirmed in 16 (42.1%) of 38 patients and 38 (9.7%) of 391 dissected lymph node levels. There were no significant differences between PET/MR, MR and PET and MR (p > 0.05) regarding accuracy for cervical metastatic disease. Based on lymph node levels, sensitivity and specificity for metastatic involvement were 65.8% and 97.2% for MR, 86.8% and 97.0% for PET and 89.5% and 95.2% for PET/MR.

Conclusions

In head and neck cancer, FDG PET/MR does not significantly improve accuracy for cervical lymph node metastases in comparison to MR or PET.     

Septate or bicornuate uterus: Accuracy of three-dimensional trans-vaginal ultrasonography and pelvic magnetic resonance imaging

Objective

To estimate the accuracy of 3-dimensional transvaginal ultrasonography (3D-TVUS), hysterosalpingography (HSG) and pelvic magnetic resonance imaging (MRI) in the differentiation between septate and bicornuate uterus.

Patients and methods

Thirty-six patients with suspected septate or bicornuate uterus on 2D ultrasound or hysterosalpingography (HSG) underwent 3D-TVUS examination, MR imaging, diagnostic laparoscopy and hysteroscopy. HSG was performed only for those patients who did not undergo the procedure before (21 patients), we retrospectively revised the hysterosalpingography of 15 patients performed outside our hospital with acceptable quality.

Results

HSG showed sensitivity of 77.4%, specificity of 60% and overall accuracy of 75% in the differentiation between the septate and bicornuate uterus. MRI showed sensitivity of 93.5%, specificity of 80%, PPV of 96.6% and negative predicative value of 66.6%, with overall accuracy of 91.6%. The 3D ultrasound showed the highest diagnostic parameters, with sensitivity of 96.7%, specificity of 100%, PPV of 100% and negative predicative value of 83.3%, with overall accuracy of 97.2%.

Conclusions

Transvaginal 3-D ultrasonography is accurate for diagnosis and differentiation between septate uterus and bicornuate uterus. We recommend 3-D transvaginal ultrasonography as the first and only mandatory step in the assessment of the uterine cavity in patients with a suspected septate or bicornuate uterus, especially before planning surgery. MRI should be preserved for patients in whom 3D TVS is not possible like virgins.     

Utility of the broccoli sign in the distinction of prolapsed uterine tumor from cervical tumor

Objective

To describe the utility, histopathological basis, and clinical correlates of the broccoli sign.

Methods

The committee on human research approved this HIPAA compliant study and waived written informed consent. Based on the records of the senior author and our multidisciplinary Gynecologic Oncology Tumor Board, we retrospectively identified thirteen women (mean age of 48.8 years; range, 34–74) with a cervical mass seen at MR imaging (n = 13) or CT (n = 5) that demonstrated the previously reported broccoli sign (i.e., a soft tissue stalk connecting the cervical mass to the uterine cavity) on one or other modality. All available clinical, imaging, and histopathological records were reviewed, with particular emphasis on initially suspected diagnosis, final proven diagnosis, and outcome.

Results

Cervical cancer was the initial clinically suspected diagnosis in 6 of 13 patients. Surgical resection demonstrated prolapsed uterine tumor in all patients, consisting of endometrioid adenocarcinoma (n = 7), carcinosarcoma (n = 2), adenosarcoma (n = 1), and leiomyoma (n = 3). Excluding the three patients with leiomyomas, currently, 7 patients with malignant tumors are disease free after a mean interval of 15 months (range, 3–45) and 3 patients have been lost to follow-up.

Conclusion

A stalk connecting an apparent cervical mass seen at CT or MR imaging to the endometrial cavity (“broccoli sign”) favors the diagnosis of a prolapsed uterine tumor; these prolapsed uterine tumors can often be malignant but appear to have a good prognosis.     

Association between magnetic resonance imaging findings of uterine leiomyomas and symptoms demanding treatment

Purpose

To evaluate the association between magnetic resonance imaging (MRI) derived uterine and leiomyoma characteristics and symptoms demanding treatment.

Materials and methods

Consecutive patients (n = 122; mean age, 47.5 years) with symptomatic leiomyomas participated in a prospective study. The leiomyoma/endometrium relationship, sizes of leiomyomas and uteri, and number and enhancement of leiomyomas were determined by MRI. Submucosal leiomyomas were classified as protruding either ≥50% or <50% into the uterine cavity.

Results

Sixty-nine patients (57%) had menorrhagia and pressure symptoms, while 26 (21%) had only menorrhagia and 27 (22%) pressure symptoms alone. Leiomyomas with ≥50% protrusion into the uterine cavity were detected more often in patients with both symptoms or just menorrhagia than in those with pressure symptoms only (18/69 [26%] versus 1/27 [4%], P = 0.013; 10/26 [39%] versus 1/27 [4%], P = 0.002, respectively). The degree of enhancement of leiomyomas was higher (P = 0.005) and leiomyomas were smaller (P = 0.002) in patients with menorrhagia than in those with pressure symptoms. Large uterine and leiomyoma measures were associated with increased urinary frequency (P values 0.002–0.032). Urinary stress incontinence, abdominal pain, and pressure on the back were not associated with MRI findings.

Conclusion

In comparison with pressure symptoms, menorrhagia is associated with smaller uterine and leiomyoma size and with more intense enhancement. While a submucosal leiomyoma largely protruding into the cavity contributes to menorrhagia, significance of a minor submucosal component seems to be unclear. The large leiomyoma and uterine volumes contribute to increased urinary frequency, whereas other mechanisms for urinary stress incontinence and pain symptoms should be considered.     

Magnetic resonance imaging of cervical carcinoma using an endorectal surface coil

Introduction

The objective of this trial is to investigate the diagnostic value of magnetic resonance imaging (MRI) with an endorectal surface coil for precise local staging of patients with histologically proven cervical cancer by comparing the radiological, clinical, and histological results.

Materials and methods

Women with cervical cancer were recruited for this trial between February 2007, and September 2010. All the patients were clinically staged according to the FIGO classification and underwent radiological staging by MRI that employed an endorectal surface coil. The staging results after surgery were compared to histopathology in all the operable patients.

Results

A total of 74 consecutive patients were included in the trial. Forty-four (59.5%) patients underwent primary surgery, whereas 30 (40.5%) patients were inoperable according to FIGO and underwent primary radiochemotherapy. The mean age of the patients was 50.6 years. In 11 out of the 44 patients concordant staging results were obtained by all three staging modalities. Thirty-two of the 44 patients were concordantly staged by FIGO and histopathological examination, while only 16 were concordantly staged by eMRI and histopathological examination. eMRI overstaged tumors in 14 cases and understaged them in 7 cases.

Conclusions

eMRI is applicable in patients with cervical cancer, yet of no benefit than staging with FIGO or standard pelvic MRI. The most precise preoperative staging procedure still appears to be the clinical examination.     

MRI of rectal carcinoma: Preoperative staging and planning of sphincter-sparing surgery

Background

Rectal cancer constitutes about one-third of all gastrointestinal tract tumors. Because of its high recurrence rates reaching 30%, it is vitally important to accurately stage these tumors preoperatively, so that appropriate surgical resection can be undertaken. MRI is used to assist in staging, identifying patients who may benefit from preoperative chemotherapy–radiation therapy, and in surgical planning.

Aim

To determine the accuracy of MRI in the preoperative staging and planning of surgical management of rectal carcinoma.

Subjects and methods

Twenty-five patients (14 males, 11 females) with rectal carcinoma were included in this study. MRI scans were performed prior to surgery in all patients, on a 1.5T scanner, and images were evaluated by three experienced radiologists. Inter-observer agreement between the three radiologists and the correlation between the imaging findings, histopathology and operative findings were evaluated.

Results

MRI findings were correctly predictive of T category in 21 cases (accuracy, 84%). In 19 (86.4%) of the 22 resectable cases, sphincter-sparing surgical approaches were accurately chosen on the basis of MRI findings.

Conclusion

MRI of rectal cancer is accurate for prediction of tumor stage and the feasibility of sphincter-sparing surgery, which are the main factors affecting the outcome of surgery.     

Value of fusion of PET and MRI for staging of endometrial cancer: Comparison with F-FDG contrast-enhanced PET/CT and dynamic contrast-enhanced pelvic MRI

Purpose

To investigate the diagnostic value of retrospective fusion of pelvic MRI and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET images for assessment of locoregional extension and nodal staging of endometrial cancer.

Materials and methods

Thirty patients with biopsy-proven endometrial cancer underwent preoperative contrast-enhanced PET/CT (PET/ceCT) and pelvic dynamic contrast-enhanced MRI for initial staging. Diagnostic performance of PET/ceCT, contrast-enhanced MRI, and retrospective image fusion from PET and MRI (fused PET/MRI) for assessing the extent of the primary tumor (T stage) and metastasis to regional LNs (N stage) was evaluated by two experienced readers. Histopathological and follow-up imaging results were used as the gold standard. The McNemar test was employed for statistical analysis.

Results

Fused PET/MRI and MRI detected 96.7% of the primary tumors, whereas PET/ceCT detected 93.3%. Accuracy for T status was 80.0% for fused PET/MRI, and MRI proved significantly more accurate than PET/ceCT, which had an accuracy of 60.0% (p = 0.041). Patient-based sensitivity, specificity and accuracy for detecting pelvic nodal metastasis were 100%, 96.3% and 96.7% for both fused PET/MRI and PET/ceCT, and 66.7%, 100% and 96.7% for MRI, respectively. These three parameters were not statistically significant (p = 1).

Conclusion

Fused PET/MRI, which complements the individual advantages of MRI and PET, is a valuable technique for assessment of the primary tumor and nodal staging in patients with endometrial cancer.     

Systematic review of flexion/extension radiography of the cervical spine in trauma patients

Introduction

The aim of this review was to investigate whether Flexion/Extension (F/E) radiography adds diagnostic value to CT or MRI in the detection of cervical spine ligamentous injury and/or clinically significant cervical spine instability of blunt trauma patients.

Methods

A systematic search of literature was done in Pubmed, Embase and Cochrane Library databases. Primary outcome was sensitivity and specificity of F/E radiography. Secondary outcomes were the positive predicting value (PPV) and negative predicting value (NPV) (with CT or MRI as reference tests due to the heterogeneity of the included studies) of each modality and the quality of F/E radiography.

Results

F/E radiography was overall regarded to be inferior to CT or MRI in the detection of ligamentous injury. This was reflected by the high specificity and NPV for CT with F/E as reference test (ranging from 97 to 100% and 99 to 100% respectively) and the ambiguous results for F/E radiography with MRI as its reference test (0–98% and 0–83% for specificity and NPV respectively). Image quality of F/E radiography was reported to have 31 to 70% adequacy, except in two studies which reported an adequacy of respectively 4 and 97%.

Conclusion

This systematic review of the literature shows that F/E radiography adds little diagnostic value to the evaluation of blunt trauma patients compared to CT and MRI, especially in those cases where CT or MRI show no indication of ligamentous injury.     

MR imaging of bladder endometriosis and its relationship with the anterior uterine wall: experience in a tertiary referral centre

Objective

Both the intraperitoneal seeding and the uterine-vesical extension theory have been proposed to explain the pathogenesis of bladder endometriosis. The aim of this study was to describe MR imaging findings of bladder endometriosis and involvement of the anterior uterine wall in a tertiary referral centre for endometriosis in a effort to improve diagnosis and help clarify the pathogenesis.

Methods

In a single-centre, retrospective study (2004–2009), 463 consecutive patients analysed for deep infiltrating endometriosis (DIE) were studied independently by two experienced readers for the presence of bladder endometriosis. MR studies revealing bladder endometriosis were then analysed in consensus for: location, size, signal intensity characteristics, uterine involvement, continuity with adenomyosis and presence of cysts. There was histopathologic correlation in 9 patients who had undergone partial bladder resection.

Results

Bladder endometriosis was diagnosed in 32 patients on MR imaging (k = 0.85). Most lesions showed heterogeneous isointensity compared to that of muscle on T2-weighed imaging, containing foci of high signal intensity, suggesting cystic ectopic endometrial glands. On T1-weighted imaging lesions showed heterogeneous isointensity with foci or small cysts, demonstrating high signal intensity, indicating hemorrhage, was observed. Uterine involvement was found in 94% of the lesions, with either “continuous” or “hourglass” configurations. Presence of contiguous adenomyosis was found in only 4 lesions.

Conclusions

With MR imaging, uterine involvement in bladder endometriosis is frequently found and in most cases located subserosally, suggesting extensive DIE, favouring the intraperitoneal seeding theory.     

Role of magnetic resonance imaging in pre-operative assessment of ano-rectal fistula

Aim of the work

To evaluate the role of magnetic resonance imaging (MRI) in preoperative assessment of ano-rectal fistula and tracing its full extent and relationship.

Materials and methods

Twenty-four patients with ano-rectal fistula were enrolled in this study. They were examined with different MRI sequences for evaluation of the fistulas and their extent. Fistulas were classified according to St. James’s University Hospital MRI based classification system (which correlates the Parks surgical classification to anatomic MRI findings) into 5 grades. Then, interrelation between surgical and MRI findings was statistically analyzed with evaluation of the accuracy of each MRI sequence used.

Results

Grade 1 was the most frequent (37.5%) type of ano-rectal fistula. The most common location of the internal opening of the fistula was at 6 o’clock position. Combination of oblique coronal and axial planes of contrast-enhanced fat suppressed T1-weighed fast spin-echo (CE FS T1WFSE) sequence images showed the highest accuracy (99.4%) in diagnosis of ano-rectal fistula.

Conclusion

MRI is a useful imaging tool in the preoperative assessment of ano-rectal fistula. A significant accordance between surgical and MRI findings was achieved by using combination of coronal and axial planes of CE FS T1WFSE sequence images.     

Imaging of the uterovaginal anomalies

Objective

To assess the role of different imaging modalities including ultrasonography, hysterosalpingogram, and magnetic resonance imaging in detection of variable Müllerian anomalies. Preoperative proper diagnosis data about Müllerian anomalies necessary for clear indications of how and when to operate.

Patients and methods

A retrospective MRI study of 34 patients was done in the period from February 2008 to February 2010, their age ranging from 3 months to 38 years (mean 24 years), with uterovaginal anomalies. Ultrasonography was performed for all cases; HSG was performed in 16 cases before MRI imaging.

Results

MRI is the most reliable method for evaluating uterovaginal anomalies, particularly in pediatrics and virgins. MRI is an accurate examination for identification and categorization of MDAs and should be carried out prior to any surgery, in this study MRI allowed correct diagnosis of 34 uterine anomalies (accuracy 100%) whereas US was correct in 30 out of 34 cases (accuracy 88%). HSG had a limited role as cannot be preformed for virgins, and cannot identify non-communicating horns in unicornuate cases.

Conclusion

MRI is the examination of choice in uterovaginal anomalies. Endovaginal ultrasound cannot be preformed for children or females who have never had sexual intercourse. TAUS have not proved completely reliable in Müllerian duct anomalies.     

Can unenhanced multiparametric MRI substitute gadolinium-enhanced MRI in the characterization of vertebral marrow infiltrative lesions?

Purpose

To assess the diagnostic effectiveness of unenhanced-multiparametric magnetic resonance imaging (mp MRI) as an alternative to gadolinium (Gad)-enhanced MRI in the characterization of vertebral marrow infiltrative lesions.

Patients and methods

A prospective evaluation of fifty-six patients with suspected or untreated vertebral metastases undergoing MRI of the spine at 1.5 T was carried out. Two groups of sequences were assigned and compared for the characterization of marrow infiltrative lesions: group [A] unenhanced-mp MRI (including T1-weighted, T2-weighted, short time inversion recovery (STIR), diffusion weighted imaging (DWI) and in/opposed phase sequences) and group [B] gadolinium-enhanced MRI (including T1-weighted, T2-weighted, STIR and T1-weighted fat-suppressed gadolinium-enhanced sequence). Qualitative and quantitative image analysis was performed and compared. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy for both imaging techniques were calculated.

Results

There was no statistical significant difference between unenhanced-multiparametric MRI and gadolinium-enhanced MRI as regards their diagnostic performance in differentiating benign from malignant vertebral marrow infiltrative lesions (p > 0.05) with calculated sensitivity (94% vs. 97%), specificity (92% vs. 88%), positive predictive value (94% vs. 91%), negative predictive value (92% vs. 95%) and (93% vs. 93%) accuracy.

Conclusion

Unenhanced-multiparametric MRI is compatible with gadolinium-enhanced MRI in reliable characterization of marrow infiltrative lesions. The routine MRI protocol of cancer patients should be altered to accommodate the evolving MRI technology and cost effectively substitute the need for a gadolinium enhanced scan.     

Value of retrospective image fusion of F-FDG PET and MRI for preoperative staging of head and neck cancer: Comparison with PET/CT and contrast-enhanced neck MRI

Purpose

To assess the clinical value of retrospective image fusion of neck MRI and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET for locoregional extension and nodal staging of neck cancer.

Materials and methods

Thirty patients with carcinoma of the oral cavity or hypopharynx underwent PET/CT and contrast-enhanced neck MRI for initial staging before surgery including primary tumor resection and neck dissection. Diagnostic performance of PET/CT, MRI, and retrospective image fusion of PET and MRI (fused PET/MRI) for assessment of the extent of the primary tumor (T stage) and metastasis to regional lymph nodes (N stage) was evaluated.

Results

Accuracy for T status was 87% for fused PET/MRI and 90% for MRI, thus proving significantly superior to PET/CT, which had an accuracy of 67% (p = 0.041 and p = 0.023, respectively). Accuracy for N status was 77% for both fused PET/MRI and PET/CT, being superior to MRI, which had an accuracy of 63%, although the difference was not significant (p = 0.13). On a per-level basis, the sensitivity, specificity and accuracy for detection of nodal metastasis were 77%, 96% and 93% for both fused PET/MRI and PET/CT, compared with 49%, 99% and 91% for MRI, respectively. The differences for sensitivity (p = 0.0026) and accuracy (p = 0.041) were significant.

Conclusion

Fused PET/MRI combining the individual advantages of MRI and PET is a valuable technique for assessment of staging neck cancer.     

Conventional magnetic resonance imaging versus MR arthrography (MRA) of the wrist in the evaluation of triangular fibrocartilage lesions

Objective

The aim of this study is to assess the diagnostic value of direct MR arthrography compared to conventional MR imaging in the diagnosis of different pathologic entities affecting the triangular fibrocartilage.

Subjects and methods

This study included 51 patients complaining of chronic wrist pain. Conventional MRI and MR arthrography (MRA) was done for all cases.

Results

A comparison of the sensitivity of conventional MRI versus MRA was done by correlating the final diagnosis of each modality with the results of arthroscopy. MRI revealed a sensitivity (SEN) of 88.5%, specificity (SPE) of 100%, positive predictive value (PPV) of 100%, and a negative predictive value (NPV) of 69.2%, with an overall accuracy (ACC) of 90.9%, while MRA revealed a SEN of 94.2%, SPE of 100%, PPV of 100%, NPV of 81.8%, and ACC of 95.5%.

Conclusion

MR arthrography is a potent additional tool facilitating the diagnosis of different pathologic entities affecting the triangular fibrocartilage requiring surgical intervention and help to reduce arthroscopic interventions.     

Nasopharyngeal tuberculosis: CT and MRI findings in thirty-six patients

Purpose

Tuberculosis is uncommon in the nasopharynx. The purpose of this study was to investigate the CT and MRI features of 36 cases of tuberculosis in this area.

Materials and methods

CT (n = 15) and MRI (n = 21) scans from 36 patients with histologically proved tuberculosis of the nasopharynx were reviewed by two experienced radiologists, paying particular attention to the lesions’ distribution, location, extent, size, internal architecture, pattern, and degree of enhancement, and cervical lymphadenopathy.

Results

Twenty-nine patients exhibited a polypoid mass pattern and seven had diffuse mucosal thickening. The roof of the nasopharynx was involved in all cases. The mean size of the lesions was 11.4 mm. Striped pattern was detected in 19 cases. Adjacent muscle invasion or bone destruction was not detected. Heterogeneous enhancement was detected in all patients, and necrosis in the nasopharyngeal lesions was detected in 16 cases. Poor, moderate, and marked enhancement was detected in one, 27, and eight cases, respectively. Thirty-four patients had involvement of the cervical lymph nodes. Twenty-two and 28 cases were associated with bilateral lymphadenopathy or necrosis, respectively. The retropharyngeal lymph node was the most commonly involved site (94.1%).

Conclusion

The presence of necrosis and striped pattern in nasopharyngeal lesions, site predilection, no invasion of regional structures, and central necrosis with peripheral rim enhancement of cervical lymphadenopathy may suggest the diagnosis of nasopharyngeal tuberculosis.