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P L Munk

Publications and source records attributed to P L Munk.

At least 37 records · Page 2Linked to original sources
PubMed2002

The imaging spectrum of Baker's (Popliteal) cysts.

Baker's (Popliteal) cysts are frequently encountered on cross-sectional imaging of the knee. These consist of enlarged gastrocnemius semimembranosus bursa which typically communicate with the knee. They may be imaged with a variety of techniques including arthopgraphy, CT, ultrasound and MRI, with the latter two being more commonly used. Examples of bursa imaged with all of the above techniques are demonstrated in the essay, as well as variance of normal appearance and pathological entities including ruptured bursa, abnormally positioned bursa, osteochondromatosis, septic complications of the bursa and pigmented villonodular synovitis.

Diagnosis, Differential↗
PubMed2002

Von Hippel-Lindau disease: a radiological essay.

Von Hippel-Lindau disease is a progressive autosomal dominant disorder with multi-organ involvement. A variety of benign and malignant disease processes lie within the spectrum of disease processes associated with this condition. Early detection and treatment of complications is paramount in the management of these patients. The purpose of this pictorial review is to depict the various radiological manifestations that are commonly seen in this disease.

Central Nervous System Neoplasms↗
PubMed2001

MRI of spinal hardware: comparison of conventional T1-weighted sequence with a new metal artifact reduction sequence.

OBJECTIVE: This study was designed to compare diagnostic quality of MR images of patients with spinal hardware acquired using a conventional T1-weighted spin-echo sequence and a new metal artifact reduction sequence (MARS). CONCLUSION: The new MARS sequence effectively reduces the degree of tissue-obscuring artifact produced by spinal fixation hardware and subjectively improves image quality compared with the conventional T1-weighted spin-echo sequence.

Adult↗
PubMed2001

Quantitative assessment of an MR technique for reducing metal artifact: application to spin-echo imaging in a phantom.

OBJECTIVE: To quantify image artifact reduction using a new technique (MARS--metal artifact reduction sequence) in vitro. DESIGN: Coronal T1-weighted MR images were obtained through two metal phantoms (titanium/chromium-cobalt and stainless steel femoral prostheses) immersed in water. Comparison of artifact volume was made with images obtained using conventional and modified (MARS) T1-weighted sequences. Signal intensity values outside a range of +/-40% the average signal intensity for water were considered artifact and segmented into low or high signal artifact categories. Considering the arbitrary selection of this threshold value, volumetric calculations of artifact were also evaluated at +/-50%, 60%, 70%, and 80% the mean signal for water. RESULTS: Conventional T1-weighted images produced 87% more low signal artifact and 212% more high signal artifact compared with the MARS modified T1-weighted images of the stainless steel prosthesis. Conventional T1-weighted images of the titanium prosthesis produced 84% more low signal artifact and 211% more high signal artifact than the MARS modified sequence. The level of artifact reduction was essentially uniform for the various threshold levels tested and was greatest at +/-20% the global signal intensity average for water. CONCLUSION: The MARS technique reduces the volume of image signal artifact produced by stainless steel and titanium/chromium-cobalt femoral prostheses on T1-weighted spin-echo images in a tissue phantom model.

Artifacts↗
PubMed2001

MR imaging features of bizarre parosteal osteochondromatous proliferation of bone (Nora's lesion).

The purpose of this study was to review the imaging findings of three patients with bizarre parosteal osteochrondromatous proliferation of bone (BPOP). The plain radiographs and MRI images of three patients with BPOP were obtained and retrospectively reviewed. In two cases, BPOP involved the feet. In one case BPOP involved the hand. In all three cases, plain radiographs showed a well-defined calcium containing mass adjacent to the cortical surface of the adjacent bone. The underlying bone appeared normal in all cases. On MRI, the lesion was of low signal intensity on T1 weighted sequences in all cases. On FSE T2 weighted and STIR sequences, the lesion was of high signal in all cases. The cortex, medullary cavity and adjacent soft tissues appeared normal in all cases. While BPOP is rare and often confused with a variety of both benign and malignant lesions, there are specific radiological findings that may help to distinguish BPOP from many of its mimickers.

Adolescent↗
PubMed2001

Malignant chondroid syringoma of the skin: magnetic resonance imaging features.

Skin tumours are usually divided into melanoma and non-melanoma types. Malignancies of the adnexal structures, of which sweat gland tumours are an example, are characterized under the non-melanoma types. Sweat gland malignancies are rare tumours that are usually associated with a poor prognosis. Given the rarity of these tumours, MRI findings of such tumours have not been described previously in the literature. We present a case report of an unusual malignant tumour of sweat gland origin known as a malignant chondroid syringoma of the skin with described MRI features. The MRI features are non-specific depicting intermediate signal intensity, changes on the proton density sequence and increased signal on the T2 and STIR-weighted sequences. Although these imaging features are characteristic of most soft tissue masses MRI can, in most cases, accurately depict the anatomic extent and identify tissue of origin, depth of invasion and relation to adjacent structures, such as muscles and bones. Thus high-resolution MRI of the skin in the future can be extremely helpful in characterizing and staging dermal neoplasms.

Adenoma, Pleomorphic↗
PubMed2001

Radiological percutaneous gastrostomy.

Long-term gastrostomy tubes have a widely accepted role in providing nutritional support. Traditionally, they have been placed by surgeons and by endoscopists. In the last decade, radiologists have come to play a major role in the placement of gastrostomy and gastrojejunostomy devices, and can usually do so as effectively and at lesser expense. A technique for placement is outlined, with a discussion of patient selection and complications. A review of the literature is provided.

Ascites↗