Biomedical subjects
Publications and source records attributed to P McArthur.
The value of using the technique of magic angle MR imaging to demonstrate finger tendons is explored. Images of fresh frozen cadaveric specimens are presented and the structures that can be visualized in the finger are described. The results suggest that magic angle MR imaging may be a useful non-invasive technique of visualizing the details of the tendons and their surrounds in the hand.
Pituitary gland is an uncommon site of a primary cancer. Of more than 600 cases of pituitary tumors seen at the KFSH&RC between 1975 to 1998 only 3 patients had primary pituitary cancer. We have previously reported a case of pituitary fibrosarcoma arising as a rare complication of external radiotherapy (ERT) for GH-secreting pituitary adenoma (PA) [1]. We report now 2 cases of ACTH-producing primary pituitary carcinoma (ACTH-PPC); their follow-up data provide information on the natural history of this cancer. Patient #1; a 46 year old lady with Cushing's disease (CD) presented with an enlarged right cervical lymph node (LN) 2 years after having undergone a partial hypophysectomy through transsphenoidal surgery (PHYPX/TSS) and ERT for an invasive pituitary tumor. Patient #2; a 26 year old man presented with CD and underwent bilateral adrenalectomy (ADx) and pituitary ERT. Thirty-nine months later he developed Nelson's syndrome and a PHYPX/TSS was performed. Incidentally discovered hepatic metastases in this patient and an excisional biopsy of the LN in patient #1 showed histological features very similar to the pituitary tumor, and they stained strongly positive for ACTH. Perinuclear spherical hyalinized cytoplasmic inclusions were seen in the LN biopsy that corresponded to bundles of type 1 microfilaments (specific for pituitary ACTH-producing cells) seen by electron microscopy. A whole body 18-Fluoro-2-Deoxy-D-Glucose positron emission (FDG-PET) scanning, showed an intense uptake in the neck mass. A trial of octreotide did not change the exceedingly high levels of ACTH in patient #2, further supporting the diagnosis of ACTH-PPC. The clinical course of 102 months prior to his demise showed continued progression of the primary and the metastatic tumor. Patient #1, is alive at 15 months follow-up; hypercortisolemia is controlled using ketoconazole. ACTH-PPC should be entertained in a patient with CD presenting with persistent cervical lymphadenopathy. The clinical course in our patients suggests that the emergence of PC may involve a proliferative continuum from a pre-existing PA to an invasive tumor, culminating in a carcinoma. Adjunctive events such as ERT/ADx may predispose to the evolution of PC in genetically susceptible individuals. Because ERT is an effective treatment for PA its use will continue; it is important to be aware of the possible complication of primary pituitary carcinoma.
Sixteen ruptured extensor tendons were repaired in seven rheumatoid hands using autogenous palmaris longus tendon as a free interposition graft. The patients were reviewed at an average of 17 months (range, 5-45) after repair. Subjectively all patients were satisfied with the clinical results, and achieved a return to their level of ability before tendon rupture. A biomechanical model suggests that tendon repair using an interposition graft, rather than a traditional end-to-side tendon transfer retains the anatomical axis of tendon function, and achieves greater forces during active finger extension.
A case of severe inflammation with an exuberant granulation lesion of the larynx that mimicked laryngeal tumour is presented. A patient who was a chronic smoker, with a history of hoarse voice underwent multiple endoscopies and biopsies, confirmed histopathologically as acute and, subsequently, as chronic inflammation. The tumour-like tissue in the larynx responded dramatically to prolonged antibiotic treatment. We emphasize the importance of histological confirmation before embarking on removal of an essential organ or part of the body which could lead to physical or emotional scarring.
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The King Faisal Specialist Hospital and Research Centre is the only center in the Middle East that incorporates a neutron therapy facility. The neutron beam is produced by a cyclotron, which produces a beam by either a (d(15)+Be) or (p(26)+Be) reaction. The beam from the proton reaction is selected for therapy because of its superior physical characteristics. These were verified by an intercomparison conducted by the European Organization for Research on Treatment of Cancer (EORTC) Heavy Particle Therapy Group. Full beam data are presented. The first study in the neutron therapy Program is on the treatment of squamous cancers of the head and neck. This consists of two parts. Part I is a dose searching phase and Part II is a comparison of our current photon treatment versus neutrons using the neutron dose selected by Part I of the study. Results of the dose searching phase (Part I) are presented.
This communication describes the design and application of a receiver coil operating at liquid nitrogen temperature and intended as a surface coil in a whole-body imager. Its particular application is seen as the external receiver for parasitic internal or implanted detectors.
The traditional management of acute cholecystitis is initial conservative treatment with antibiotics followed by elective cholecystectomy. Although early cholecystectomy has often been advocated, there has been only one randomized controlled clinical trial comparing the two methods of treatment. This paper reports the preliminary results of such a trial in which 32 patients have been studied so far. Of the 17 patients managed conservatively, there was a misdiagnosis in 2 (11-8 per cent). In the remaining 15 patients with acute cholecystitis 3 (20 per cent) required urgent operation because of failure of medical treatment. Elective cholecystectomy was not technically difficult. Of the 15 patients treated by early cholecystectomy, there was a misdiagnosis in 1 (6-8 per cent). Surgery was technically difficult in 2 patients but cholecystectomy was possible in all. The former 2 patients required blood transfusion, but in the remainder the estimated blood loss was only slightly more than in the elective group. There was no mortality in either group nor any complication directly attributable to the biliary surgery. The incidence of minor postoperative complications was only slightly greater in those treated by early operation. The length of postoperative stay was similar in both groups but those treated conservatively spent an average of 11 more days in hospital. The preliminary results indicate that those treated by early cholecystectomy spend less time in hospital and avoid the complications of failed conservative treatment without the added risk of increased postoperative mortality and major complications.
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Explore the source record for details and available documents.
Four dimensional chemical shift imaging was used to map the relative peak heights of phosphorus metabolites of the liver and overlying skeletal muscle of a normal subject and two patients. The technique provides 31P spectra localised on a voxel-by-voxel basis and may be valuable in mapping heterogeneous structural and metabolic changes in disease.