Bert Foer - Academia.edu (original) (raw)

Papers by Bert Foer

Research paper thumbnail of Xanthogranulomatous pyelonephritis in a child

Journal belge de radiologie, 1993

Xanthogranulomatous pyelonephritis is an uncommon form of chronic aggressive infection of the kid... more Xanthogranulomatous pyelonephritis is an uncommon form of chronic aggressive infection of the kidney and surrounding tissues usually affecting middle aged women. It is rarely seen in childhood. We report the case of a female child with a history of fatigue, progressive anorexia, and fever in whom a diagnosis of pyelonephritis on a predisposing factor of lithiasis was suggested. After initial antibiotic treatment, nephrectomy was needed for an acute general deterioration. Pathology demonstrated xanthogranulomatous pyelonephritis.

Research paper thumbnail of Temporal Bone Imaging Techniques

Medical Radiology, 2014

Multi-slice CT and Cone Beam CT are actually both used to image the temporal bone. Two completely... more Multi-slice CT and Cone Beam CT are actually both used to image the temporal bone. Two completely different MR protocols are used to respectively image the inner ear and middle ear.

Research paper thumbnail of Handling an Isolated Malleus Handle Fracture

Annals of Otology, Rhinology & Laryngology, 2014

Background: An isolated malleus handle fracture is rare and presents with vague otological sympto... more Background: An isolated malleus handle fracture is rare and presents with vague otological symptoms. Diagnosis depends on careful history taking and otoscopic examination. Different treatment options are available. Reconstruction with hydroxyapatite bone cement is a relatively new technique. Objective: The aim of this article is to review the current diagnostic work-up and treatment options and to demonstrate our method of treatment with hydroxyapatite bone cement. Methods: Three cases, repaired with hydroxyapatite bone cement in a tertiary referral otologic center, were retrospectively analyzed. A review of the literature on diagnosis and treatment procedures was performed. Results: One fracture occurred by withdrawing a finger from the external auditory canal and 2 occurred without clear prior trauma. Our 3 cases were successfully repaired with hydroxyapatite bone cement. Conclusion: Diagnosis of an isolated malleus handle fracture still depends on careful clinical examination. In...

Research paper thumbnail of Les applications de la diffusion en imagerie : t�te et cou

Research paper thumbnail of Apparent Diffusion Coefficient Measurement as an Early Marker of Response to Chemotherapy in Hepatic Metastasis: Evaluation of Feasibility and Reproducibility

PURPOSE To evaluate the apparent diffusion coefficient (ADC) as an early predictor of response to... more PURPOSE To evaluate the apparent diffusion coefficient (ADC) as an early predictor of response to chemotherapy in liver metastasis and to determine the reproducibility of the technique. METHOD AND MATERIALS In a prospective study 20 patients with histologically proven primary tumors (18 colorectal, 1 breast, 1 esophageal carcinoma) and with documented liver metastasis were included prior to chemotherapy. 31 metastases were analysed. Diffusion weighted imaging (DWI) was performed using a navigator based respiratory triggered echo planar imaging sequence twice before therapy on separate days and 12 to 14 days after the beginning of treatment. Lesions were classified as responders or non responders according to the change in size after the end of treatment. ADC was calculated as an absolute value and relative to liver parenchyma (ADClesion/ADCliver). Mann-Whitney U test and Wilcoxon's signed ranks test were performed to evaluate change in ADC and difference between responders versu...

Research paper thumbnail of HEAD AND NECK RADIOLOGY The value of single-shot turbo spin-echo diffusion-weighted MR imaging in the detection of middle ear cholesteatoma

Introduction Single-shot (SS) turbo spin-echo (TSE) diffu-sion-weighted (DW) magnetic resonance i... more Introduction Single-shot (SS) turbo spin-echo (TSE) diffu-sion-weighted (DW) magnetic resonance imaging (MRI) is a non echo-planar imaging (EPI) technique recently reported for the evaluation of middle ear cholesteatoma. We prospectively evaluated a SS TSE DW sequence in detecting congenital or acquired middle ear cholesteatoma and evaluated the size of middle ear cholesteatoma detectable with this sequence. The aim of this study was not to differentiate between inflammatory tissue and cholesteatoma using SS TSE DW imaging. Methods A group of 21 patients strongly suspected clinically and/or otoscopically of having a middle ear cholesteatoma without any history of prior surgery were evaluated with late post-gadolinium MRI including this SS TSE DW sequence. Results A total of 21 middle ear cholesteatomas (5 congenital and 16 acquired) were found at surgery with a size varying between 2 and 19 mm. Hyperintense signal on SS TSE DW imaging compatible with cholesteatoma was found in 19 pa...

Research paper thumbnail of Imaging of Cerebellopontine Angle and Internal Auditory Canal Lesions

Medical Radiology, 2014

Imaging of the cerebellopontine angle and internal auditory canal has become one of the cornersto... more Imaging of the cerebellopontine angle and internal auditory canal has become one of the cornerstones of modern head and neck imaging. Due to advances in imaging techniques with newer magnetic resonance (MR) sequences using thinner slice thickness and a higher resolution, the scala of detectable pathologies has increased tremendously. In this chapter, the lesions in and around the cerebellopontine angle cistern (CPA) are discussed, trying to emphasize some characteristic imaging features of most lesions. After illustrating the imaging protocol and imaging anatomy, pathological entities in this chapter will be discussed upon origin and/or location.

Research paper thumbnail of Magnetic resonance imaging of cholesteatoma: an update

B-ENT, 2009

To report on the value and limitations of new MRI techniques in pre- and post-operative MRI of ch... more To report on the value and limitations of new MRI techniques in pre- and post-operative MRI of cholesteatoma. The current value of magnetic resonance imaging (MRI) in diagnosing congenital, acquired, and post-operative recurrent or residual cholesteatoma is described. High resolution computed tomography (HRCT) is still considered the imaging modality of choice for detecting acquired or congenital middle ear cholesteatoma. However, MRI may provide additional information on the delineation and extension of cholesteatoma and on potential complications. Detecting post-operative residual or recurrent cholesteatoma with HRCT was shown to be inaccurate due to the technique's low sensitivity and specificity. Recently, improvements in MRI techniques have led to a more accurate diagnoses of cholesteatoma using delayed contrast enhanced T1-weighted imaging and diffusion-weighted imaging.

Research paper thumbnail of Subarcuate supralabyrinthine approach for supralabyrinthine petrosal cholesteatoma

The Annals of otology, rhinology, and laryngology, 2010

Congenital cholesteatomas of the petrosal apex account for 1% to 3% of all cholesteatomas and oft... more Congenital cholesteatomas of the petrosal apex account for 1% to 3% of all cholesteatomas and often present an important surgical challenge. This report describes an exceptional case of a "nondestructive" translabyrinthine surgical approach to a large congenital petrosal cholesteatoma that threatened the vestibulum, superior semicircular canal, facial nerve, and internal auditory canal. We applied a nonconventional transmastoid subarcuate supralabyrinthine approach in a 20-year-old patient by accessing the lesion through the center of the superior semicircular arch without damaging the integrity of the canal. This led to a complete removal of the petrosal cholesteatoma with preservation of hearing and vestibular function. Follow-up imaging performed 1 and 2 years after operation by means of non-echo-planar diffusion-weighted imaging did not show residual cholesteatoma. This report describes the first successful use of a subarcuate supralabyrinthine approach through the arc...

Research paper thumbnail of Tumors and tumor-like lesions of the jaw mixed and radiopaque lesions

JBR-BTR : organe de la Société royale belge de radiologie (SRBR) = orgaan van de Koninklijke Belgische Vereniging voor Radiologie (KBVR)

Radiopaque lesions and lesions of mixed radioopacity are far less frequent than their radiolucent... more Radiopaque lesions and lesions of mixed radioopacity are far less frequent than their radiolucent counterparts. Included in this spectrum are infectious and metastatic disease, inherited and developmental disorders and rare tumoral lesions. This article deals with the imaging features that may assist in the (differential) diagnosis of these lesions. in many instances, the radiological characterization is typical (osteoma, enostoma, fibrous dysplasia, Paget disease...), obviating the need for further invasive histological confirmation. Other lesions may share overlapping clinical, radiological and pathological features. In these cases, correlation of histopathological diagnosis with clinical findings and imaging features is of utmost importance for a correct diagnosis.

Research paper thumbnail of Tumors and tumor-like lesions of the jaw: radiolucent lesions

JBR-BTR : organe de la Société royale belge de radiologie (SRBR) = orgaan van de Koninklijke Belgische Vereniging voor Radiologie (KBVR)

Radiolucent lesions within the jaws represent a whole variety of lesions. Generally, they can be ... more Radiolucent lesions within the jaws represent a whole variety of lesions. Generally, they can be classified into two categories. The first category comprises well circumscribed lesions, either unilocular, multilobular or multilocular. They may be further subdivided into odontogenic or nonodontogenic lesions. The key feature that distinguishes these two subgroups is the relationship with the underlying dentition. Poorly circumscribed radiolucent lesions are the second category and consist of acute infectious disease and primary or metastatic malignancies. Although many of these lesions may present with non-specific imaging characteristics, careful analysis of a combination of imaging parameters may suggest a presumptive diagnosis. This article discusses the imaging features on different imaging techniques that may be useful in the characterization of these lesions.

Research paper thumbnail of Intralabyrinthine Schwannomas, More Common Than Previously Thought: How Do They Present, How Do They Grow, and Do They Need Treatment?

Research paper thumbnail of Imaging of Temporal Bone Tumors

Neuroimaging Clinics of North America, 2009

Tumoral lesions of the temporal bone are relatively rare. Cross-sectional imaging plays an import... more Tumoral lesions of the temporal bone are relatively rare. Cross-sectional imaging plays an important role in the description of extension of these lesions. In certain lesions, imaging characteristics are rather specific, giving a clue to diagnosis. The most common tumoral lesions of the external, middle, and inner ear are discussed. Some rare lesions are also highlighted.

Research paper thumbnail of Middle Ear Cholesteatoma: Non–Echo-planar Diffusion-weighted MR Imaging versus Delayed Gadolinium-enhanced T1-weighted MR Imaging—Value in Detection

Radiology, 2010

To retrospectively compare non-echo-planar (non-EP) diffusion-weighted (DW) imaging, delayed gado... more To retrospectively compare non-echo-planar (non-EP) diffusion-weighted (DW) imaging, delayed gadoliniumenhanced T1-weighted magnetic resonance (MR) imaging, and the combination of both techniques in the evaluation of patients with cholesteatoma. Materials and Methods: This institutional review board-approved study, for which the need to obtain informed consent was waived, included 57 patients clinically suspected of having a middle ear cholesteatoma without a history of surgery and 63 patients imaged before "second-look" surgery. Four blinded radiologists evaluated three sets of MR images: a set of delayed gadolinium-enhanced T1-weighted images, a set of non-EP DW images, and a set of both kinds of images. Overall sensitivity, specifi city, negative predictive value (NPV), and positive predictive value (PPV), as well as intra-and interobserver agreement, were assessed and compared among methods. To correct for the correlation between different readings, a generalized estimating equations logistic regression model was fi tted. Results were compared with surgical results, which were regarded as the standard of reference. Results: Sensitivity, specifi city, NPV, and PPV were signifi cantly different between the three methods (P , .005). Sensitivity and specifi city, respectively, were 56.7% and 67.6% with the delayed gadolinium-enhanced T1-weighted images and 82.6% and 87.2% with the non-EP DW images. Sensitivity for the combination of both kinds of images was 84.2%, while specifi city was 88.2%. The overall PPV was 88.0% for delayed gadolinium-enhanced T1-weighted images, 96.0% for non-EP DW images, and 96.3%for the combination of both kinds of images. The overall NPV was 27.0% for delayed gadolinium-enhanced T1-weighted images, 56.5% for non-EP DW images, and 59.6% for the combination of both kinds of images. Conclusion: MR imaging for detection of middle ear cholesteatoma can be performed by using non-EP DW imaging sequences alone. Use of the non-EP DW imaging sequence combined with a delayed gadolinium-enhanced T1-weighted sequence yielded no signifi cant increases in sensitivity, specifi city, NPV, or PPV over the use of the non-EP DW imaging sequence alone.

Research paper thumbnail of Congenital Bilateral Oval and Round Window Aplasia with a Hypoplastic Stapes

Otology & Neurotology, 2006

᭤ These authors demonstrate the usefulness of HRMR imaging. It especially is helpful in determini... more ᭤ These authors demonstrate the usefulness of HRMR imaging. It especially is helpful in determining, as this study indicates, the size of the cochlear nerve relative to various degrees of sensorineural deafness in children.

Research paper thumbnail of Mastoid and Epitympanic Bony Obliteration in Pediatric Cholesteatoma

Otology & Neurotology, 2008

Objective: The primary goal of cholesteatoma surgery is complete eradication of the disease. To l... more Objective: The primary goal of cholesteatoma surgery is complete eradication of the disease. To lower the recurrence rate in the pediatric population in canal wall up techniques and to avoid the disadvantages of canal wall down techniques, the bony obliteration technique with epitympanic and mastoid obliteration has been developed. The objective of this study was to evaluate the long-term surgical outcome and recurrence rate of this technique in children. Study Design: Retrospective case review. Setting: Tertiary referral center. Patients: Fifty-two children (G16 yr) were operated on in 90.4% (n = 47) for a primary or recurrent cholesteatoma and in 9.6% (n = 5) for an unstable cavity. Intervention: In all cases, we closed the tympanoattical barrier and the posterior tympanotomy with sculpted cortical bone and then completed obliteration of the epitympanum and mastoid with bone pâté. A reconstruction of the middle ear was performed by means of an allograft tympanic membrane including the malleus handle and a sculpted allograft malleus or incus for columellar reconstruction. Main Outcome Measures: Recurrent rate; residual rate; functional outcome; hygienic status of the ear; long-term safety issues. Results: The mean follow-up time was 49.5 months (range, 12Y101.3 mo). Recurrent cholesteatoma occurred in 1.9% (n = 1). Residual cholesteatoma was detected in 15.4% (n = 8) of the cases. Postoperative hearing results revealed a median gain on pure-tone averages of 14.3 dB and a median postoperative air-bone gap of 25.6 dB. Conclusion: The mastoid and epitympanic BOT is an effective technique to lower the recurrence rate of cholesteatoma in the pediatric population. Follow-up by magnetic resonance imaging provides a safe, noninvasive method for postoperative detection of residual cholesteatoma.

Research paper thumbnail of The value of diffusion-weighted MR imaging in the diagnosis of primary acquired and residual cholesteatoma: a surgical verified study of 100 patients

European Radiology, 2006

Our goal was to determine the value of echo-planar diffusionweighted MR imaging in detecting the ... more Our goal was to determine the value of echo-planar diffusionweighted MR imaging in detecting the presence of primary acquired and residual cholesteatoma. One hundred patients were evaluated by preoperative magnetic resonance (MR) imaging with diffusion-weighted MR imaging. The patient population consisted of a first group of 55 patients evaluated in order to detect the presence of a primary acquired cholesteatoma. In the second group, 45 patients were evaluated for the presence of a residual cholesteatoma 8-18 months after cholesteatoma surgery, prior to second-look surgery. Surgical findings were compared with preoperative findings on diffusionweighted imaging (DWI). The sensitivity, specificity, positive and negative predictive values of both groups was assessed. In the group of primary surgery patients, hyperintense signal compatible with cholesteatoma was found in 89% of cases with a sensitivity, specificity, positive and negative predictive value for DWI of 81, 100, 100 and 40%, respectively. In the group of second-look surgery patients, only one of seven surgically verified residual cases was correctly diagnosed using DWI, with a sensitivity, specificity, positive and negative predictive values of 12.5, 100, 100 and 72%, respectively. These results confirm the value of DWI in detecting primary cholesteatoma, but show the poor capability of DWI in detecting small residual cholesteatoma.

Research paper thumbnail of CT and MR imaging of congential abnormalities of the inner ear and internal auditory canal

European Journal of Radiology, 2001

The embryology of the inner ear must be known as many of the inner ear malformations present as a... more The embryology of the inner ear must be known as many of the inner ear malformations present as a result of the arrest during the various stages of embryology. These malformations are described in this 'embryologic' perspective and specific names for certain malformations are no longer used. Both CT and MR can be used to look at inner ear malformations but often both techniques are complementary. However, CT is preferred when associated middle-or external ear malformations must be excluded. Magnetic resonance is preferred when subtle changes in the membranous labyrinth or abnormalities of the nerves in the internal auditory canal must be visualised. The CT and MR technique must however be adapted as more and more subtle congenital malformations can only be seen when the right technique is used. The heavily T2-weighted gradient-echo or fast spin-echo MR techniques are mandatory if malformations of the inner ear must be excluded. The purpose of this paper is to describe the techniques used to study these patients and to give an overview of the most frequent and important congenital malformations which can be found in the inner ear and internal auditory canal/cerebellopontine angle.

Research paper thumbnail of Pathology of the vestibulocochlear nerve

European Journal of Radiology, 2010

This article covers congenital deformity of the internal auditory canal (IAC), neoplastic and pse... more This article covers congenital deformity of the internal auditory canal (IAC), neoplastic and pseudoneoplastic lesions with special detailed emphasis on schwannoma of the eight cranial nerve (acoustic neuroma), non-neoplastic IAC/cerebellopontine angle mass (CPA) pathology, including vascular loops and numerous additional differential diagnostic entities with particular emphasis on nonneoplastic meningeal disease.

Research paper thumbnail of Diagnosis of liver metastases: Can diffusion-weighted imaging (DWI) be used as a stand alone sequence?

European Journal of Radiology, 2012

Objectives: To evaluate if diffusion-weighted MRI (DWI) can replace gadolinium-enhanced MRI (Gd-M... more Objectives: To evaluate if diffusion-weighted MRI (DWI) can replace gadolinium-enhanced MRI (Gd-MRI) for diagnosing liver metastases. The diagnostic accuracy of both techniques alone and in combination are compared. Materials and methods: Sixty-eight patients with histologically proven primary extrahepatic tumors were included in this retrospective study. Lesions included 62 metastases and 130 benign lesions. Three image sets (unenhanced T1 and T2/gadolinium enhanced T1 (Gd-MRI), DWI and combination of both) were reviewed independently by 3 observers. The areas under the receiver operating characteristic curves (A z), sensitivity and specificity for the 3 image sets were compared. The standard of reference was either histopathology or multi-modality and clinical follow-up. Results: Pooled data showed higher diagnostic accuracy for the combined set (A z = 0.93) compared to Gd-MRI (p = 0.001) and DWI (p < 0.0001). No difference was found between the performance of Gd-MRI and DWI (p = 0.09). Sensitivity for the combined set was higher than Gd-MRI (p = 0.0003) and DWI (p = 0.0034). Specificity for DWI was lower than Gd-MRI (p < 0.0001) and the combined set (p < 0.0001). Conclusion: The diagnostic performance of DWI is equal to that of Gd-MRI. DWI alone can be used in patients where gadolinium contrast administration is not allowed. Combination of Gd-MRI and DWI significantly increases diagnostic accuracy.

Research paper thumbnail of Xanthogranulomatous pyelonephritis in a child

Journal belge de radiologie, 1993

Xanthogranulomatous pyelonephritis is an uncommon form of chronic aggressive infection of the kid... more Xanthogranulomatous pyelonephritis is an uncommon form of chronic aggressive infection of the kidney and surrounding tissues usually affecting middle aged women. It is rarely seen in childhood. We report the case of a female child with a history of fatigue, progressive anorexia, and fever in whom a diagnosis of pyelonephritis on a predisposing factor of lithiasis was suggested. After initial antibiotic treatment, nephrectomy was needed for an acute general deterioration. Pathology demonstrated xanthogranulomatous pyelonephritis.

Research paper thumbnail of Temporal Bone Imaging Techniques

Medical Radiology, 2014

Multi-slice CT and Cone Beam CT are actually both used to image the temporal bone. Two completely... more Multi-slice CT and Cone Beam CT are actually both used to image the temporal bone. Two completely different MR protocols are used to respectively image the inner ear and middle ear.

Research paper thumbnail of Handling an Isolated Malleus Handle Fracture

Annals of Otology, Rhinology & Laryngology, 2014

Background: An isolated malleus handle fracture is rare and presents with vague otological sympto... more Background: An isolated malleus handle fracture is rare and presents with vague otological symptoms. Diagnosis depends on careful history taking and otoscopic examination. Different treatment options are available. Reconstruction with hydroxyapatite bone cement is a relatively new technique. Objective: The aim of this article is to review the current diagnostic work-up and treatment options and to demonstrate our method of treatment with hydroxyapatite bone cement. Methods: Three cases, repaired with hydroxyapatite bone cement in a tertiary referral otologic center, were retrospectively analyzed. A review of the literature on diagnosis and treatment procedures was performed. Results: One fracture occurred by withdrawing a finger from the external auditory canal and 2 occurred without clear prior trauma. Our 3 cases were successfully repaired with hydroxyapatite bone cement. Conclusion: Diagnosis of an isolated malleus handle fracture still depends on careful clinical examination. In...

Research paper thumbnail of Les applications de la diffusion en imagerie : t�te et cou

Research paper thumbnail of Apparent Diffusion Coefficient Measurement as an Early Marker of Response to Chemotherapy in Hepatic Metastasis: Evaluation of Feasibility and Reproducibility

PURPOSE To evaluate the apparent diffusion coefficient (ADC) as an early predictor of response to... more PURPOSE To evaluate the apparent diffusion coefficient (ADC) as an early predictor of response to chemotherapy in liver metastasis and to determine the reproducibility of the technique. METHOD AND MATERIALS In a prospective study 20 patients with histologically proven primary tumors (18 colorectal, 1 breast, 1 esophageal carcinoma) and with documented liver metastasis were included prior to chemotherapy. 31 metastases were analysed. Diffusion weighted imaging (DWI) was performed using a navigator based respiratory triggered echo planar imaging sequence twice before therapy on separate days and 12 to 14 days after the beginning of treatment. Lesions were classified as responders or non responders according to the change in size after the end of treatment. ADC was calculated as an absolute value and relative to liver parenchyma (ADClesion/ADCliver). Mann-Whitney U test and Wilcoxon's signed ranks test were performed to evaluate change in ADC and difference between responders versu...

Research paper thumbnail of HEAD AND NECK RADIOLOGY The value of single-shot turbo spin-echo diffusion-weighted MR imaging in the detection of middle ear cholesteatoma

Introduction Single-shot (SS) turbo spin-echo (TSE) diffu-sion-weighted (DW) magnetic resonance i... more Introduction Single-shot (SS) turbo spin-echo (TSE) diffu-sion-weighted (DW) magnetic resonance imaging (MRI) is a non echo-planar imaging (EPI) technique recently reported for the evaluation of middle ear cholesteatoma. We prospectively evaluated a SS TSE DW sequence in detecting congenital or acquired middle ear cholesteatoma and evaluated the size of middle ear cholesteatoma detectable with this sequence. The aim of this study was not to differentiate between inflammatory tissue and cholesteatoma using SS TSE DW imaging. Methods A group of 21 patients strongly suspected clinically and/or otoscopically of having a middle ear cholesteatoma without any history of prior surgery were evaluated with late post-gadolinium MRI including this SS TSE DW sequence. Results A total of 21 middle ear cholesteatomas (5 congenital and 16 acquired) were found at surgery with a size varying between 2 and 19 mm. Hyperintense signal on SS TSE DW imaging compatible with cholesteatoma was found in 19 pa...

Research paper thumbnail of Imaging of Cerebellopontine Angle and Internal Auditory Canal Lesions

Medical Radiology, 2014

Imaging of the cerebellopontine angle and internal auditory canal has become one of the cornersto... more Imaging of the cerebellopontine angle and internal auditory canal has become one of the cornerstones of modern head and neck imaging. Due to advances in imaging techniques with newer magnetic resonance (MR) sequences using thinner slice thickness and a higher resolution, the scala of detectable pathologies has increased tremendously. In this chapter, the lesions in and around the cerebellopontine angle cistern (CPA) are discussed, trying to emphasize some characteristic imaging features of most lesions. After illustrating the imaging protocol and imaging anatomy, pathological entities in this chapter will be discussed upon origin and/or location.

Research paper thumbnail of Magnetic resonance imaging of cholesteatoma: an update

B-ENT, 2009

To report on the value and limitations of new MRI techniques in pre- and post-operative MRI of ch... more To report on the value and limitations of new MRI techniques in pre- and post-operative MRI of cholesteatoma. The current value of magnetic resonance imaging (MRI) in diagnosing congenital, acquired, and post-operative recurrent or residual cholesteatoma is described. High resolution computed tomography (HRCT) is still considered the imaging modality of choice for detecting acquired or congenital middle ear cholesteatoma. However, MRI may provide additional information on the delineation and extension of cholesteatoma and on potential complications. Detecting post-operative residual or recurrent cholesteatoma with HRCT was shown to be inaccurate due to the technique's low sensitivity and specificity. Recently, improvements in MRI techniques have led to a more accurate diagnoses of cholesteatoma using delayed contrast enhanced T1-weighted imaging and diffusion-weighted imaging.

Research paper thumbnail of Subarcuate supralabyrinthine approach for supralabyrinthine petrosal cholesteatoma

The Annals of otology, rhinology, and laryngology, 2010

Congenital cholesteatomas of the petrosal apex account for 1% to 3% of all cholesteatomas and oft... more Congenital cholesteatomas of the petrosal apex account for 1% to 3% of all cholesteatomas and often present an important surgical challenge. This report describes an exceptional case of a "nondestructive" translabyrinthine surgical approach to a large congenital petrosal cholesteatoma that threatened the vestibulum, superior semicircular canal, facial nerve, and internal auditory canal. We applied a nonconventional transmastoid subarcuate supralabyrinthine approach in a 20-year-old patient by accessing the lesion through the center of the superior semicircular arch without damaging the integrity of the canal. This led to a complete removal of the petrosal cholesteatoma with preservation of hearing and vestibular function. Follow-up imaging performed 1 and 2 years after operation by means of non-echo-planar diffusion-weighted imaging did not show residual cholesteatoma. This report describes the first successful use of a subarcuate supralabyrinthine approach through the arc...

Research paper thumbnail of Tumors and tumor-like lesions of the jaw mixed and radiopaque lesions

JBR-BTR : organe de la Société royale belge de radiologie (SRBR) = orgaan van de Koninklijke Belgische Vereniging voor Radiologie (KBVR)

Radiopaque lesions and lesions of mixed radioopacity are far less frequent than their radiolucent... more Radiopaque lesions and lesions of mixed radioopacity are far less frequent than their radiolucent counterparts. Included in this spectrum are infectious and metastatic disease, inherited and developmental disorders and rare tumoral lesions. This article deals with the imaging features that may assist in the (differential) diagnosis of these lesions. in many instances, the radiological characterization is typical (osteoma, enostoma, fibrous dysplasia, Paget disease...), obviating the need for further invasive histological confirmation. Other lesions may share overlapping clinical, radiological and pathological features. In these cases, correlation of histopathological diagnosis with clinical findings and imaging features is of utmost importance for a correct diagnosis.

Research paper thumbnail of Tumors and tumor-like lesions of the jaw: radiolucent lesions

JBR-BTR : organe de la Société royale belge de radiologie (SRBR) = orgaan van de Koninklijke Belgische Vereniging voor Radiologie (KBVR)

Radiolucent lesions within the jaws represent a whole variety of lesions. Generally, they can be ... more Radiolucent lesions within the jaws represent a whole variety of lesions. Generally, they can be classified into two categories. The first category comprises well circumscribed lesions, either unilocular, multilobular or multilocular. They may be further subdivided into odontogenic or nonodontogenic lesions. The key feature that distinguishes these two subgroups is the relationship with the underlying dentition. Poorly circumscribed radiolucent lesions are the second category and consist of acute infectious disease and primary or metastatic malignancies. Although many of these lesions may present with non-specific imaging characteristics, careful analysis of a combination of imaging parameters may suggest a presumptive diagnosis. This article discusses the imaging features on different imaging techniques that may be useful in the characterization of these lesions.

Research paper thumbnail of Intralabyrinthine Schwannomas, More Common Than Previously Thought: How Do They Present, How Do They Grow, and Do They Need Treatment?

Research paper thumbnail of Imaging of Temporal Bone Tumors

Neuroimaging Clinics of North America, 2009

Tumoral lesions of the temporal bone are relatively rare. Cross-sectional imaging plays an import... more Tumoral lesions of the temporal bone are relatively rare. Cross-sectional imaging plays an important role in the description of extension of these lesions. In certain lesions, imaging characteristics are rather specific, giving a clue to diagnosis. The most common tumoral lesions of the external, middle, and inner ear are discussed. Some rare lesions are also highlighted.

Research paper thumbnail of Middle Ear Cholesteatoma: Non–Echo-planar Diffusion-weighted MR Imaging versus Delayed Gadolinium-enhanced T1-weighted MR Imaging—Value in Detection

Radiology, 2010

To retrospectively compare non-echo-planar (non-EP) diffusion-weighted (DW) imaging, delayed gado... more To retrospectively compare non-echo-planar (non-EP) diffusion-weighted (DW) imaging, delayed gadoliniumenhanced T1-weighted magnetic resonance (MR) imaging, and the combination of both techniques in the evaluation of patients with cholesteatoma. Materials and Methods: This institutional review board-approved study, for which the need to obtain informed consent was waived, included 57 patients clinically suspected of having a middle ear cholesteatoma without a history of surgery and 63 patients imaged before "second-look" surgery. Four blinded radiologists evaluated three sets of MR images: a set of delayed gadolinium-enhanced T1-weighted images, a set of non-EP DW images, and a set of both kinds of images. Overall sensitivity, specifi city, negative predictive value (NPV), and positive predictive value (PPV), as well as intra-and interobserver agreement, were assessed and compared among methods. To correct for the correlation between different readings, a generalized estimating equations logistic regression model was fi tted. Results were compared with surgical results, which were regarded as the standard of reference. Results: Sensitivity, specifi city, NPV, and PPV were signifi cantly different between the three methods (P , .005). Sensitivity and specifi city, respectively, were 56.7% and 67.6% with the delayed gadolinium-enhanced T1-weighted images and 82.6% and 87.2% with the non-EP DW images. Sensitivity for the combination of both kinds of images was 84.2%, while specifi city was 88.2%. The overall PPV was 88.0% for delayed gadolinium-enhanced T1-weighted images, 96.0% for non-EP DW images, and 96.3%for the combination of both kinds of images. The overall NPV was 27.0% for delayed gadolinium-enhanced T1-weighted images, 56.5% for non-EP DW images, and 59.6% for the combination of both kinds of images. Conclusion: MR imaging for detection of middle ear cholesteatoma can be performed by using non-EP DW imaging sequences alone. Use of the non-EP DW imaging sequence combined with a delayed gadolinium-enhanced T1-weighted sequence yielded no signifi cant increases in sensitivity, specifi city, NPV, or PPV over the use of the non-EP DW imaging sequence alone.

Research paper thumbnail of Congenital Bilateral Oval and Round Window Aplasia with a Hypoplastic Stapes

Otology & Neurotology, 2006

᭤ These authors demonstrate the usefulness of HRMR imaging. It especially is helpful in determini... more ᭤ These authors demonstrate the usefulness of HRMR imaging. It especially is helpful in determining, as this study indicates, the size of the cochlear nerve relative to various degrees of sensorineural deafness in children.

Research paper thumbnail of Mastoid and Epitympanic Bony Obliteration in Pediatric Cholesteatoma

Otology & Neurotology, 2008

Objective: The primary goal of cholesteatoma surgery is complete eradication of the disease. To l... more Objective: The primary goal of cholesteatoma surgery is complete eradication of the disease. To lower the recurrence rate in the pediatric population in canal wall up techniques and to avoid the disadvantages of canal wall down techniques, the bony obliteration technique with epitympanic and mastoid obliteration has been developed. The objective of this study was to evaluate the long-term surgical outcome and recurrence rate of this technique in children. Study Design: Retrospective case review. Setting: Tertiary referral center. Patients: Fifty-two children (G16 yr) were operated on in 90.4% (n = 47) for a primary or recurrent cholesteatoma and in 9.6% (n = 5) for an unstable cavity. Intervention: In all cases, we closed the tympanoattical barrier and the posterior tympanotomy with sculpted cortical bone and then completed obliteration of the epitympanum and mastoid with bone pâté. A reconstruction of the middle ear was performed by means of an allograft tympanic membrane including the malleus handle and a sculpted allograft malleus or incus for columellar reconstruction. Main Outcome Measures: Recurrent rate; residual rate; functional outcome; hygienic status of the ear; long-term safety issues. Results: The mean follow-up time was 49.5 months (range, 12Y101.3 mo). Recurrent cholesteatoma occurred in 1.9% (n = 1). Residual cholesteatoma was detected in 15.4% (n = 8) of the cases. Postoperative hearing results revealed a median gain on pure-tone averages of 14.3 dB and a median postoperative air-bone gap of 25.6 dB. Conclusion: The mastoid and epitympanic BOT is an effective technique to lower the recurrence rate of cholesteatoma in the pediatric population. Follow-up by magnetic resonance imaging provides a safe, noninvasive method for postoperative detection of residual cholesteatoma.

Research paper thumbnail of The value of diffusion-weighted MR imaging in the diagnosis of primary acquired and residual cholesteatoma: a surgical verified study of 100 patients

European Radiology, 2006

Our goal was to determine the value of echo-planar diffusionweighted MR imaging in detecting the ... more Our goal was to determine the value of echo-planar diffusionweighted MR imaging in detecting the presence of primary acquired and residual cholesteatoma. One hundred patients were evaluated by preoperative magnetic resonance (MR) imaging with diffusion-weighted MR imaging. The patient population consisted of a first group of 55 patients evaluated in order to detect the presence of a primary acquired cholesteatoma. In the second group, 45 patients were evaluated for the presence of a residual cholesteatoma 8-18 months after cholesteatoma surgery, prior to second-look surgery. Surgical findings were compared with preoperative findings on diffusionweighted imaging (DWI). The sensitivity, specificity, positive and negative predictive values of both groups was assessed. In the group of primary surgery patients, hyperintense signal compatible with cholesteatoma was found in 89% of cases with a sensitivity, specificity, positive and negative predictive value for DWI of 81, 100, 100 and 40%, respectively. In the group of second-look surgery patients, only one of seven surgically verified residual cases was correctly diagnosed using DWI, with a sensitivity, specificity, positive and negative predictive values of 12.5, 100, 100 and 72%, respectively. These results confirm the value of DWI in detecting primary cholesteatoma, but show the poor capability of DWI in detecting small residual cholesteatoma.

Research paper thumbnail of CT and MR imaging of congential abnormalities of the inner ear and internal auditory canal

European Journal of Radiology, 2001

The embryology of the inner ear must be known as many of the inner ear malformations present as a... more The embryology of the inner ear must be known as many of the inner ear malformations present as a result of the arrest during the various stages of embryology. These malformations are described in this 'embryologic' perspective and specific names for certain malformations are no longer used. Both CT and MR can be used to look at inner ear malformations but often both techniques are complementary. However, CT is preferred when associated middle-or external ear malformations must be excluded. Magnetic resonance is preferred when subtle changes in the membranous labyrinth or abnormalities of the nerves in the internal auditory canal must be visualised. The CT and MR technique must however be adapted as more and more subtle congenital malformations can only be seen when the right technique is used. The heavily T2-weighted gradient-echo or fast spin-echo MR techniques are mandatory if malformations of the inner ear must be excluded. The purpose of this paper is to describe the techniques used to study these patients and to give an overview of the most frequent and important congenital malformations which can be found in the inner ear and internal auditory canal/cerebellopontine angle.

Research paper thumbnail of Pathology of the vestibulocochlear nerve

European Journal of Radiology, 2010

This article covers congenital deformity of the internal auditory canal (IAC), neoplastic and pse... more This article covers congenital deformity of the internal auditory canal (IAC), neoplastic and pseudoneoplastic lesions with special detailed emphasis on schwannoma of the eight cranial nerve (acoustic neuroma), non-neoplastic IAC/cerebellopontine angle mass (CPA) pathology, including vascular loops and numerous additional differential diagnostic entities with particular emphasis on nonneoplastic meningeal disease.

Research paper thumbnail of Diagnosis of liver metastases: Can diffusion-weighted imaging (DWI) be used as a stand alone sequence?

European Journal of Radiology, 2012

Objectives: To evaluate if diffusion-weighted MRI (DWI) can replace gadolinium-enhanced MRI (Gd-M... more Objectives: To evaluate if diffusion-weighted MRI (DWI) can replace gadolinium-enhanced MRI (Gd-MRI) for diagnosing liver metastases. The diagnostic accuracy of both techniques alone and in combination are compared. Materials and methods: Sixty-eight patients with histologically proven primary extrahepatic tumors were included in this retrospective study. Lesions included 62 metastases and 130 benign lesions. Three image sets (unenhanced T1 and T2/gadolinium enhanced T1 (Gd-MRI), DWI and combination of both) were reviewed independently by 3 observers. The areas under the receiver operating characteristic curves (A z), sensitivity and specificity for the 3 image sets were compared. The standard of reference was either histopathology or multi-modality and clinical follow-up. Results: Pooled data showed higher diagnostic accuracy for the combined set (A z = 0.93) compared to Gd-MRI (p = 0.001) and DWI (p < 0.0001). No difference was found between the performance of Gd-MRI and DWI (p = 0.09). Sensitivity for the combined set was higher than Gd-MRI (p = 0.0003) and DWI (p = 0.0034). Specificity for DWI was lower than Gd-MRI (p < 0.0001) and the combined set (p < 0.0001). Conclusion: The diagnostic performance of DWI is equal to that of Gd-MRI. DWI alone can be used in patients where gadolinium contrast administration is not allowed. Combination of Gd-MRI and DWI significantly increases diagnostic accuracy.