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Biomedical subjects

D F Martin

Publications and source records attributed to D F Martin.

At least 109 records · Page 6Linked to original sources

Relief of metastatic biliary obstruction by stent placement: is it worthwhile?

Twenty-one patients undergoing stent placement for extra-hepatic biliary obstruction by metastatic disease were reviewed. Primary tumours (colorectal 8, stomach 4, breast 2, ovary 2, others 5) had been diagnosed 13 months (median) before presentation with bile duct obstruction, which was at the porta hepatis or common hepatic duct in 14 patients and in the common bile duct in seven. Endoscopic stent placement was achieved in 14 out of 20 patients in whom it was attempted. A percutaneous trans-hepatic procedure was necessary in five patients. Two patients could not be stented. Median survival was 5 months (range 1 month to 6 years) in patients stented successfully but only 1 month (2 weeks to 3 months) in unsuccessful cases (P < 0.01). Nine patients survived more than 4 months. Patients with proximal obstruction fared less well than those with distal obstruction; they required more procedures and survived for shorter periods (median 1 month versus 5 months, P < 0.05). Worthwhile palliation is afforded to almost half these patients by endoscopic stent placement and individual patients may achieve prolonged, symptom-free survival.

Adult↗

The use of effervescent agents in the small bowel meal examination.

Some perceived disadvantages of the small bowel meal examination are failure of adequate distension, lack of a double contrast effect and the duration of the procedure. A new use for effervescent granules during the small bowel meal is described which reduces the examination time by 70% and reduces the radiation dose to the patient.

Adult↗

Transabdominal ultrasonography as the primary investigation in patients with suspected Crohn's disease or recurrence: a prospective study.

Traditionally, patients with suspected or known and possible recurrent Crohn's disease have been investigated by small bowel barium radiology, which incurs a relatively high radiation dose. Despite patient selection a significant number have a normal barium examination. A prospective study was performed to evaluate the use of transabdominal ultrasound as the initial investigation in these two groups. One hundred and twenty-seven patients were examined, including 31 with a previous history of Crohn's disease. In the known Crohn's disease group there were 14 true positive ultrasound examinations and eight true negative, with six false positive and three false negative examinations. In the 96 patients not previously known to have Crohn's disease, there were 18 true positive and 70 true negative examinations, with two false positive and six false negative examinations. The overall sensitivity for ultrasound was 78% with a specificity of 91%. A significant learning curve was apparent in the early stages of study; in the last 64 patients the sensitivity was increased to 87%. These data support the use of ultrasound as the initial investigation in patients with suspected Crohn's disease or recurrence, prior to consideration for small bowel barium radiology, to reduce the large number of unnecessary small bowel barium examinations currently being performed.

Adult↗

Intraocular lymphoma. Clinical and histopathologic diagnosis.

BACKGROUND: Intraocular lymphoma is associated with significant morbidity and mortality, but early diagnosis and treatment may improve prognosis. METHODS: The diagnostic features of 12 cases of intraocular lymphoma diagnosed at the National Eye Institute between 1984 and 1992 were retrospectively reviewed. RESULTS: A pathologic diagnosis of large B-cell lymphoma was made on vitrectomy specimens in ten patients, cerebral spinal fluid in one, and on an enucleation specimen in one. The mean time from onset of symptoms to diagnosis was 21.4 months (range, 1-66 months). All 12 patients were given a final diagnosis of non-Hodgkin's lymphoma of the central nervous system (NHL-CNS), based on the epidemiology, pathology, and clinical course of their tumors. Although an initial vitrectomy was negative for malignant cells in three of ten patients, a repeat vitrectomy specimen subsequently showed intraocular lymphoma. Results of examination of the cerebrospinal fluid (CSF) showed malignant cells in 5 of 11 patients, although malignant cells were only identified after repeat examination of additional samples of CSF in three of these patients. Malignant cells often are difficult to identify, and an experienced cytopathologist was critical in making the correct diagnosis. In addition, corticosteroids are lympholytic to the lymphoma cells, and they appeared to decrease the viability of tumor cells obtained in samples of vitreous and CSF. CONCLUSION: The prompt, appropriate handling of specimens and review by an experienced cytopathologist are critical to the diagnosis of intraocular lymphoma. Malignant cells often are present in the cerebral spinal fluid at the time that ocular lymphoma is diagnosed. Nevertheless, multiple vitrectomies and lumbar punctures may be necessary before the correct diagnosis is made.

Adult↗

The role of chorioretinal biopsy in the management of posterior uveitis.

BACKGROUND: The ideal management of intraocular inflammation may require a tissue diagnosis. Diagnostic vitrectomy is a well-established method for acquiring such tissue. However, in some patients, the diagnostic pathology is limited to the choroid and retina and vitrectomy may yield no useful information. In such cases, a more aggressive surgical approach to obtain tissue may be useful. METHODS: The authors performed chorioretinal biopsies on seven patients with progressive chorioretinal lesions of unknown etiology. Indications for biopsy included: (1) macular-threatening lesions unresponsive to therapy, (2) suspicion of malignancy, or (3) suspicion of an infectious etiology. In all cases, it was expected that the results would alter therapy or other aspects of clinical care. Preoperative visual acuity was 20/200 or worse in each eye biopsied with one or more peripheral chorioretinal lesions present. Biopsy specimens were divided into three parts and submitted for light and electron microscopy, immunohistochemistry, and tissue culture. RESULTS: On the basis of the biopsy findings, a diagnosis of multifocal choroiditis and subretinal fibrosis was rendered in three eyes, sarcoidosis in two eyes, and viral retinitis in two eyes. Therapy was changed in five patients. Final visual acuity was unchanged or improved in five eyes. Complications included the progression of lens opacity in all eyes and the development of phthisis in one eye that was extensively diseased preoperatively. CONCLUSION: Chorioretinal biopsy may provide useful information for determining the diagnosis and guiding the subsequent management of patients with progressive chorioretinal lesions of unknown etiology.

Adult↗

Gallbladder function after endoscopic sphincterotomy--a dynamic ultrasound assessment.

There is controversy regarding the function of the gallbladder following endoscopic sphincterotomy (ES) for the treatment of gallstones. Using ultrasound to assess gallbladder volume, we evaluated gallbladder contractility in 34 patients (18 male, 16 female), mean age 73 years, who had ES and common bile duct (CBD) clearance a mean of 18 months earlier. In 16 patients gallbladder function could not be measured, either because the fasting gallbladder was small and contracted or because it contained gas. The remaining 18 patients (53%) had "normal" gallbladder contraction with a mean initial fasting volume of 30.3 ml and mean post fatty meal volume of 13.8 ml. 14 of these 18 patients had a repeat fasting volume which showed refilling in all except one. Those with a functioning gallbladder had had significantly smaller stones extracted from the CBD at the time of ES. A smaller or incomplete sphincterotomy may have been performed in these patients, therefore allowing some residual sphincter of Oddi function.

Adult↗

The fluoroscope in a traditional sports medicine setting.

Using a fluoroscope in a sports medicine setting is a new innovation. By using a hand-held portable fluoroscope, radiographic imaging can be done in the athletic training room or at an on-site athletic location. The fluoroscope produces a high-quality, realtime image. This is accomplished immediately, without the delay time and expense involved when the injured athlete is referred to an emergency facility. Through the use of the fluoroscope, a definite diagnosis can be made, and treatment can begin immediately. The fluoroscope has proven to be cost-effective, not only by decreasing radiographic expenses, but also by decreasing the time commitment of both the athlete and the athletic trainer.

Journal Article↗

Efficacy of fluid-air exchange for postvitrectomy diabetic vitreous hemorrhage.

We reviewed the records of 33 fluid-air exchanges to assess the efficacy of fluid-air exchange in the management of recurrent vitreous cavity hemorrhage after vitrectomy for proliferative diabetic retinopathy. Fluid-air exchange alone was successful in clearing the vitreous cavity in ten of 20 eyes after a mean of 1.5 exchanges per eye. Repeat vitrectomy was required in the remaining ten eyes and anterior hyaloidal fibrovascular proliferation was frequently found. Hemorrhages that occurred in the late postoperative period (more than nine months) appeared more likely to be successfully treated with fluid-air exchange alone. Failure of the initial fluid-air exchange to induce clearing immediately after the procedure appeared to be associated with subsequent exchange failures and need for surgical intervention. Complications from the exchange procedure were infrequent with the development of peripheral retinal detachment in one eye. Our current recommendation for nonclearing recurrent postvitrectomy diabetic vitreous hemorrhage is to perform a fluid-air exchange, provided no other high-risk characteristics are present. If clearing occurs in the immediate postexchange period but rebleeding occurs at a later period, we recommend a second fluid-air exchange. If clearing does not occur in the immediate postexchange period, we recommend proceeding directly to revision of vitrectomy.

Adult↗

Management of common bile duct stones using a second-generation extracorporeal shockwave lithotriptor.

Fifty-four patients with common bile duct stones (8-36 mm in diameter) that could not be removed after endoscopic sphincterotomy, even with the use of mechanical lithotripsy, underwent extracorporeal shockwave lithotripsy (ESWL) using a Siemens Lithostar. Their median age was 75.5 (range 34-89) years. Patients received 4000-6000 shocks per session over approximately 60 min. Seventeen underwent two sessions and two patients three or more. Thirty-seven patients had one stone, ten had two, and seven had three or more. Spontaneous clearance of fragments occurred in only three patients before further endoscopic retrograde cholangiopancreatography was performed to remove fragments. Stones were removed and ducts cleared endoscopically in 35 patients, giving a total of 38 of 54 patients (70 per cent) with complete duct clearance. Fragmentation in response to lithotripsy was dependent on stone size; the number of stones had little effect. ESWL was well tolerated without any haematological or biochemical abnormality. Computed tomography in the first 20 patients showed no hepatic or pancreatic change after treatment. ESWL combined with endoscopic extraction of fragments is an alternative to surgery when preliminary endoscopic extraction and mechanical lithotripsy have failed.

Adult↗

Common bile duct diameter and complications of endoscopic sphincterotomy.

To assess the relationship between distal common bile duct (CBD) diameter and the incidence of an immediate complication following endoscopic sphincterotomy (ES), all patients undergoing ES between January 1986 and October 1990 were studied. The overall risk of an immediate complication following ES in 655 patients was 5.6 per cent (37 patients). Patients with calculi were at greater risk if the distal CBD was dilated (P < 0.001); the complication in those with stones was most likely to be haemorrhage (81 per cent). The relative risk of a complication increased ten times if the distal bile duct diameter was > 0.8 cm. Patients with stricture of the distal CBD did not have a significantly greater risk of complication than those with stones (9.7 versus 4.9 per cent). There was no significant difference between the mean distal CBD diameter of those with stricture and controls (0.61 versus 0.44 cm).

Adult↗

Perforating (through-and-through) injuries of the globe. Surgical results with vitrectomy.

Fifty-one eyes of 48 patients with perforating (through-and-through) injuries of the globe were treated with vitrectomy during a 12-year period. Functional success was obtained in 32 eyes (63%), anatomic success was obtained in nine eyes (17%), and treatment failed in 10 eyes (20%). In 16 eyes (32%), 20/20 to 20/100 visual acuity was obtained; in 17 eyes (33%), 20/200 to 5/200 visual acuity was obtained; and in 18 eyes (35%), less than 5/200 visual acuity was obtained. The mechanism of injury was an important prognostic indicator of final visual outcome. Eight (62%) of 13 eyes that sustained knife or nail injuries achieved a final visual acuity of 20/50 or better, while only six (16%) of 38 eyes [corrected] with missile injuries achieved a similar level of acuity. Final visual outcome correlated well with the state of the macula and was not predicted by preoperative visual acuity. Despite improvement in surgical techniques and instrumentation, no trend toward improved visual outcomes was identified during the 12-year period.

Adolescent↗

Endoscopic sphincterotomy: the whole truth.

An 8 year experience of 602 patients (median age 76 years) referred for endoscopic management of common bile stones is reported. No patient referred for treatment has been excluded. A diagnostic cholangiogram was achieved in 94 per cent and sphincterotomy was accomplished in 91.5 per cent. The bile ducts were demonstrated to be completely cleared of stones in 491 (81.6 per cent) of 602 patients. A mean number of 1.9 endoscopic retrograde cholangiopancreatography examinations per patient were necessary to achieve this result. Complications of endoscopic sphincterotomy, which were strictly defined, occurred in 10.5 per cent of patients although five patients had two complications (total complication rate 11.3 per cent). The 30-day mortality rate was 2.2 per cent, seven of 13 deaths (1.2 per cent) occurring as a direct result of sphincterotomy. There have been statistically significant improvements in bile duct clearance and complication rates with increasing experience of endoscopists.

Adolescent↗

Risks of leaving the gallbladder in situ after endoscopic sphincterotomy for bile duct stones.

There is controversy concerning the subsequent clinical course of patients whose gallbladder is left in situ following successful endoscopic removal of stones from their common bile ducts. A total of 191 patients (median age 76 years) were reviewed between 12 and 100 months (mean 38 months) after endoscopic sphincterotomy. Ten patients (5.2 per cent) had symptoms requiring cholecystectomy which was uneventful, nine in the first year. Cholangitis at presentation or failure to fill the gallbladder by endoscopic retrograde cholangiography were not helpful in identifying these patients. Forty-nine (25.6 per cent) patients died during the review period from non-biliary pathology (usually cardiovascular). Elective cholecystectomy is not required in elderly patients with symptomatic bile duct stones if the common bile duct can be cleared of stones after endoscopic sphincterotomy.

Adult↗

Wire guided balloon assisted endoscopic biliary stent exchange.

A simple technique of endoscopic stent exchange using a biliary dilatation balloon is described. The technique is appropriate in patients with bile duct malignancy in whom clogging of a previously placed straight stent has occurred. Balloon assisted exchange has been used in 25 patients to date and minimises the risks of failure of stent reinsertion and the need for further procedures in patients with limited life expectancy.

Catheterization↗