Diffusion-weighted imaging of the orbit

Orbital lesions compose a heterogeneous group of pathologies that often present with non-specific imaging findings on conventional magnetic resonance imaging (MRI) sequences (T1-and T2-weighted). Accordingly, the application of diffusion MRI offers an opportunity to further distinguish between lesions along this spectrum. Diffusion-weighted imaging (DWI) represents the simplest and most frequent clinically utilised diffusion imaging technique. Recent advances in DWI techniques have extended its application to the evaluation of a wider spectrum of neurological pathology, including orbital lesions. This review details the manifestations of select orbital pathology on DWI and underscores specific situations where diffusion imaging allows for increased diagnostic sensitivity compared to more conventional MRI techniques. These examples also describe preferred management for orbital lesions identified by DWI.

Reduced Responses of Submucous Neurons from Irritable Bowel Syndrome Patients to a Cocktail Containing Histamine, Serotonin, TNFα, and Tryptase (IBS-Cocktail)

BACKGROUND AND AIMS

Malfunctions of enteric neurons are believed to play an important role in the pathophysiology of irritable bowel syndrome (IBS). Our aim was to investigate whether neuronal activity in biopsies from IBS patients is altered in comparison to healthy controls (HC).

METHODS

Activity of human submucous neurons in response to electrical nerve stimulation and local application of nicotine or a mixture of histamine, serotonin, tryptase, and TNF-α (IBS-cocktail) was recorded in biopsies from 17 HC and 35 IBS patients with the calcium-sensitive-dye Fluo-4 AM. The concentrations of the mediators resembeled those found in biopsy supernatants or blood. Neuronal activity in guinea-pig submucous neurons was studied with the voltage-sensitive-dye di-8-ANEPPS.

RESULTS

Activity in submucous ganglia in response to nicotine or electrical nerve stimulation was not different between HC and IBS patients (P = 0.097 or P = 0.448). However, the neuronal response after application of the IBS-cocktail was significantly decreased (P = 0.039) independent of whether diarrhea (n = 12), constipation (n = 5) or bloating (n = 5) was the predominant symptom. In agreement with this we found that responses of submucous ganglia conditioned by overnight incubation with IBS mucosal biopsy supernatant to spritz application of this supernatant was significantly reduced (P = 0.019) when compared to incubation with HC supernatant.

CONCLUSION

We demonstrated for the first time reduced neuronal responses in mucosal IBS biopsies to an IBS mediator cocktail. While excitability to classical stimuli of enteric neurons was comparable to HC, the activation by the IBS-cocktail was decreased. This was very likely due to desensitization to mediators constantly released by mucosal and immune cells in the gut wall of IBS patients.

The role of partnership dynamics in determining the acceptability of condoms and microbicides

Microbicides are a class of substances under development that could reduce the sexual transmission of HIV and other sexually transmitted diseases when applied locally to genital mucosal surfaces. Microbicide acceptability research has largely focused on product characteristics, rather than processes of negotiation within relationships about use. Gender relations, decision-making power and communication within sexual relationships are recognised as important determinants of condom and contraceptive use, and are likely to determine microbicide use also. As part of social science research linked to the Microbicides Development Programme (MDP) we combine relationship-based theories with anthropological work conducted with women and men using a placebo gel. We explore communication and decision-making in gel and condom use, including constructions of risk and trust. During the MDP301 Phase III pilot study, in-depth interviews were conducted at sites in South Africa, Tanzania, Uganda and Zambia. Following four weeks of placebo gel use, women and their partners were asked about gel use and acceptability, partner involvement, sexual practices and condom use. Data from 45 couples at five sites were analysed using a grounded theory approach in NVivo. Participation in the study did not require women to inform their partners, yet our data shows women seeking permission from their partners, negotiating disclosure, exchanging information and persuading or motivating for gel use. Although gel was supposedly 'woman-controlled', men exercised considerable influence in determining whether and how it was used. Despite this, negotiations around use were largely successful, since the gel increased sexual pleasure and provided opportunities for intimate communication and the building of trust. Decisions about condom and microbicide use are made in a dyadic context and involve a complex negotiation of risk and trust. Whilst preferences relating to product characteristics are largely individual, use itself is dependent on partnership dynamics and the broader social context in which sexual risk management occurs.

[Surgical outcome in subtrochanteric fractures. A study over 15 years]

During the past 15 years new methods for the surgical approach to subtrochanteric fractures have been developed, e.g. the dynamic hip screw (DHS) and the gamma-nail (GN). Reviewing the results of this change in methods, we report on 102 patients after subtrochanteric fractures of the femur. We divided them into three groups according to the time of operation (1980-1984, period I; 1986-1989, period II; 1991-1993, period III). During period I, 74% of the fractures were stabilized using angle plates. During period III, more than 30% were operated on using the DHS and nearly 50% using the GN. The total hospital stay (department of surgery as well as geriatric hospital) decreased from 107.5 +/- 46.5 days to 78.9 +/- 24.3 days (P < 0.001). During period I, 86.2% of patients could be discharged home, during period III, 100%. Serious complications decreased during these 15 years. In conclusion, as observed in pertrochanteric fractures, the introduction of new operative techniques for the treatment of subtrochanteric fractures in the elderly was followed by a shortened hospital stay, a decreased complication rate and an increased rate of discharge home.

[Surgical results of pertrochanteric fractures. A 15-year study]

During the last 15 years new methods for the surgical treatment of pertrochanteric fractures have been developed [e.g. the dynamic hip screw (DHS) and the gamma-nail (GN)]. We report on the results obtained in 450 patients operated on between 1979 and 1984 (period I), from 1986 to 1989 (period II), and between 1991 and 1993 (period III); we reviewed the results with the intension of finding whether application of the new methods led to better results, shorter stay in hospital and fewer complications. The mean age of all patients was 79 years and was 4 years higher in period I to than in period III (77.5 +/- 9.2 vs 81.5 +/- 8.4). During period I, 65% of the fractures were stabilized using Ender rods, while during period III the DHS was used in nearly 60% and the GN, in 22%. The total hospital stay (department of surgery and geriatric hospital) decreased from 80.4 +/- 31.7 in period I to 66.6 +/- 24 days in period III (P < 0.001). Serious complications decreased by 80% during this time. During period I 86.2% of patients could be discharged home, as against 89.0% in period II and 94.7% during period III. The introduction of new operative techniques for the treatment of pertrochanteric fractures in the elderly was followed by a dramatic shortening of hospital stay, a reduced incidence of complications, early weight-bearing and an increased rate of discharge home.

[Preparation for colonoscopy using Golytely--a sure method? Comparative histological and clinical study between lavage and saline laxatives]

Looking at clinical side-effects, effectiveness and tolerability, we compared the salinic solution "Golytely" vs. a conventional preparatory procedure (Cascara-Salax) in a prospective study including 28 patients with macroscopic normal mucosa. Mucosal changes in colonic step biopsies were investigated according to prefixed criteria.

RESULTS

There was no significant difference concerning weight, blood pressure, pulse rate, body temperature or essential laboratory findings. Whereas preparation using Cascara-Salax was less molesting stated by the patients, there was no difference in the way colonoscopy itself was tolerated in both groups. The performing doctor's evaluation of the colonic cleaning effect and examination conditions showed "Golytely" significantly ahead of Cascara-Salax. Histologically, colonic mucous layers depicted changes in the control groups in 63% vs. 40% in the "Golytely" group. "Golytely" seems to provide a safe and effective method of preparation for colonoscopy.

[Time factors in endoscopic studies. A survey in West Germany]

In order to obtain representative data for the orientation of personal requirements in endoscopic units, 650 hospitals in the FRG were asked to have an exact look at the times they needed for endoscopic procedures during an period of 14 days. 25% of the contacted hospitals answered to this request and thus the times required for more than 14,000 endoscopic procedures for both, doctors and medical staff, could be analysed. Results revealed that most of the sophisticated procedures such as colonoscopy, ERCP (especially when they included therapeutic endoscopical methods) varied largely in time. This was caused by different factors such as the patient dependent variables, and the course of the procedure including observation of safety and hygiene standards. Average values of times needed for endoscopic procedures were as follows (time in minutes): (Table: see text). The data given above might be of value for the estimation of actual personal and time requirements in endoscopic units.

[Endotherapy of gallstones]

Choledocholithiasis is treated endoscopically by papillotomy and subsequent stone extraction. In 10% of cases this procedure does not succeed. mechanical lithotripsy has reached the stage of clinical applicability, it can be performed easily, has a high success rate, and equipment is relatively inexpensive. Alternative methods are electrohydraulic lithotripsy and chemical litholysis. Laser-, ultrasound- and jet-cutting-lithotripsy are still in a developmental stage, the latter two methods not yet having been applied in man. Endoscopic probing of the gall bladder for stone extraction or chemical litholysis with methyl-tert-butyl aether up to now have succeeded only in very few cases. Therapy of gall bladder stones by pulsed waves is already in clinical testing.

[Rectoscopy: rigid or flexible? A comparative study]

The customary rigid rectoscope was compared prospectively, with a new, flexible one (prototypes of Olympus Opt. and Fuji) in each of 114 patients selected at random. Maximal depth of introduction was reached on average after 1 min with the rigid instruments, after 1 min 40 sec with the flexible one. Mean depth of introduction was 16 cm for the rigid and 33 cm for the flexible one. In 21 patients (18.4%) additional information was obtained with the flexible rectoscope. 80% of patients reported that the flexible instrument caused them no or only slight discomfort. Skill in using the flexible instrument can be quickly acquired.

[Endoscopic intraductal radiotherapy of high bile-duct carcinoma]

A new method for palliative intraductal radiotherapy of high malignant bile duct occlusion was used in three patients. It consists of insertion of a 4 cm x 0,6 mm iridium-192 wire into the stenosis caused by the tumour. It uses a modified nasobiliary probe which is guided endoscopically retrograde transpapillary. A radiation output of 0.85 Gy/min (85 rd/min) and a requested therapeutic dosage of 60 Gy (6000 rd) at a distance of 0.5 cm lead to in situ position of the wire for about 70 hours. During that time bile flow is effected via the nasobiliary probe. The advantage over previously described methods (percutaneous transhepatic, surgical after installation of U-drainage) lies in a smaller complication rate and improved follow-up treatment as change of the endoprosthesis or repeat irradiation is not associated with renewed tissue trauma.

Electronic endoscopy of the gastrointestinal tract. Initial experience with a new type of endoscope that has no fiberoptic bundle for imaging

We report on 31 endoscopic investigations using a new type of electronic endoscope which has no fiberoptic bundle for imaging. The device carries on its tip a light-sensitive CCD chip which functions as a TV camera. The signals received are transformed by a processor and displayed on a TV monitor. The upper digestive tract was inspected in 23 patients with the electronic endoscope and in the same session, a fiberoptic-endoscopic esophagogastroduodenoscopy was carried out on 16 of them. The information obtained using the 2 systems differed neither quantitatively nor qualitatively. Because of its external diameter, it was not possible to introduce the electronic endoscope past esophageal stenoses in 2 patients. Preliminary experience with 2 types of colonoscopes in 8 patients strongly indicates that these devices are equivalent, in respect of optical quality, to the fiberoptic endoscopes. The quality and color reproduction of the TV image of the upper and lower digestive tract are excellent. Electronic endoscopy offers great potential for consultation, training and documentation. The patients tolerated the procedure very well.

[Combined irrigation and endoscopy in the treatment of biliary duct stones (author's transl)]

In ten patients with biliary duct stones reoperation was not indicated and endoscopical stone extraction after papillotomy had failed due to the size of the concrements. As in some patients cholecystectomy had been performed several years ago and in others had not been done yet, treatment was commenced via an endoscopically inserted nasobiliary tube using media dissolving cholesterol and calcium bilirubinate stones. Results of treatment were satisfactory and side effects were tolerable. Results were compared with those after treatment with glycero-1-monooctanoate (Capmul 8210). In four patients distribution in the intra and extrahepatic biliary duct system was investigated by admixture of radiographically opaque media with both irrigation fluids. It was shown that both the oily and watery phase of the irrigation media were distributed homogeneously in the duct system and that the stone surface was covered adequately.

[Endoscopy of esophageal cancer (author's transl)]

The late stages of symptomatic esophageal carcinoma rarely present diagnostic difficulties. Nevertheless, the tumor must be bioptically analyzed and defined to decide on proper treatment. Our future aim is to diagnose esophageal carcinoma at an early stage. Dysphagia should increasingly be accepted as an indication for endoscopy. Biopsy should be accompanied by cytology and vital staining. Regular controls in risk groups should help to improve the poor prognosis of esophageal carcinoma in our country.

Ultrasonic tomography by means of an ultrasonic fiberendoscope

The diagnositc value of ultrasonic tomography of the upper abdominal organs is sometimes limited by bones and gas. Endoscopic ultrasonography (EUST) combines the advantages of the direct visualization of the upper GI tube and the ultrasonic imaging of adjacent organs. The ultrasonic probe consists of a 5 MHz array that generates a good resolution at the acustical focus, the endoscope is a conventional Olympus gastroscope type GFB3. The ultrasonic transducer is firmly attached to the distal end of the endoscope. Combined examinations are performed in 18 patients with biliary, pancreatic and hepatic disorders or postoperative changes. EUST may be of value not only for gastrointestinal but also for retroperitoneal, cardiac, and mediastinal diseases.

Experiences with the long standing nasobiliary tube in biliary diseases

Specially designed longstanding nasobiliary tubes allow to reflect upon some well established therapeutic rules. The safe, decompressing effect of the tube leads to prompt relief of obstructive suppurative cholangitis. Therefore emergency of laparotomy can be avoided in high risk patients. Large common bile duct stones until now have required a large papillotomy with increased frequency of complications. The attempt to dissolve those stones with Capmul is justified on an account of a 50% success rate. Either a very small EPT or even non is necessary in order to insert the tube.

[Colonoscopy in children and juveniles (author's transl)]

Colonoscopy, as an established endoscopic procedure in adults, is thought to be of great value in children and juveniles as well. The main indications for its use are intestinal hemorrhage, polypectomy, diarrhoea of uncertain origin, uncertain x-ray findings as well as the confirmation of a diagnosis made by biopsy. The choice of instruments used, preparations prior to the examination and premedication are dependent upon the child's age. 32 children, aged between 1--14 years, and 41 juveniles between 15 and 18 years were examined. Most common diagnoses were Crohn's disease (29), polyps (7) and ulcerative colitis (4). Others were unspecific colitis (3), follicular hyperplasia of the terminal ileum (2), lymphangiectasia (2), one hemangioma and one rectal ulcer. In 24 patients endoscopy revealed nothing pathological within the colon. Examinations should be performed only by skilled endoscopists with special experience of the problems of colonoscopy in children.

Endoscopic duct obstruction in chronic pancreatitis

Ligation of Wirsung's duct or obstruction with a glue may be an alternative to pancreatectomy in patients with intractable pain due to chronic relapsing pancreatitis. In 10 patients obstruction of Wirsung's duct was performed via endoscopic retrograde instillation of an alcoholic aminoacid solution into the ductal system. All patients became free of symptoms within one week; no complications were seen. Long-term follow-up data, however, suggest that clinical improvement may be persistent in only about 50 per cent of the patients. Further data are necessary before endoscopic obstruction of Wirsung's duct can be recommended as a conservative method in the treatment of chronic pancreatitis.

Gastrointestinal fiberoptic endoscopy in pediatric patients and juveniles

Over a period of 8 years 351 upper gastrointestinal endoscopies and 72 coloscopies were performed in infants, children and juvenile patients. Development of special pediatric instruments provides increasing application even to the youngest patients. Fiberendoscopy is a safe and sensitive diagnostic tool also in the pediatric age group; furthermore the therapeutic possibilities of operative endoscopy can be used without disadvantage.

[Chronic pancreatitis--conservative versus surgical treatment under prognostic aspects]

Because of the differently selected groups of patients due to a narrow indication for pancreatic surgery, a direct comparison of the results of conservative and surgical therapy is not possible. A follow-up survey of 348 patients with proven chronic pancreatitis showed that patients suffering from uncomplicated pancreatitis should be treated conservatively as long as possible, for 70% (77 out of 109) will improve. In 2/3 of our patients with chronic pancreatitis, surgical treatment became necessary. As to the recurrence of pancreatitis and the lethality, resecting techniques were more successful (72%: 107 out of 148) than the non-resecting ones (61%: out of 91). The cooperation of the patient is crucial for the prognostic outcome regardless of the kind of treatment; especially the elimination of alcohol intake is essential. The most important accompanying or/and succeeding disease is diabetes mellitus, which impairs the long term prognosis especially because of the hazard of postoperative irreversible hypoglycemia. Optimal treatment of patients with chronic pancreatitis can only be accomplished on an individual basis and on the basis of a close cooperation of internists and surgeons.

[Peptone-stimulated gastric secretion and antacids. Effect of antacids with various content of calcium, magnesium and aluminiumions on the peptone-induced secretion of gastric juice, double-blind study]

A double-blind-trial was performed to prove the effect of antacids containing Mg (OH)2, Al (OH)3 and CaCO3 on peptone-stimulated gastric secretion (intragastric titration). A high efficacy of antacids given after meals was demonstrated. After application of antacids no significant rise in serum gastrin levels during intragastric titration was found. Serum calcium and magnesium levels remained unchanged. Peptone-stimulated gastric secretion was not influenced by application of different antacids within a period of 2 hours.

Inhibition by somatostatin of gastrin release and gastric acid responses to meals and to pentagastrin in man

The inhibitory actions of intravenous somatostatin on the gastric secretory responses to pentagastrin (1.5 microng/kg-h i.v.) and to a meal (10% peptone, pH 5.5) were studied in six healthy subjects. Meal-induced gastric acid output was estimated by means of a modified Fordtran and Walsh method of intragastric titration. Somatostatin (5 microng/kg-h; cyclic form) significantly inhibited the total 1-hour acid response to pentagastrin by about 70% (inhibition of pepsin secretion: about 70%) and that to a test meal by about 75%. During the last 30 min of somatostatin infusion the pentagastrin-stimulated secretion of acid was significantly reduced by about 90% (inhibition of pepsin output: about 85%) while the corresponding figure in the test with meal-induced secretion was about 95%. Serum gastric--elevated in response to the test meal--was found to be merely lowered by about 30% during somatostatin infusion. Consequently, it is tempting to assume that inhibition of human gastric acid secretion by exogenous somatostatin largely results from a direct antisecretory effect upon parietal cells and, only to a minor extent, from an indirect action via reduction of gastrin release.

[Morbus Crohn (enteritis regionalis)]

Crohn's disease (regional enteritis) is a chronic non-specific inflammatory intestinal disorder of unknown etiology. Most commonly the terminal ileum in involved, a segmentary involvement of the bowel wall is rather characteristic. Main symptoms are recurrent abdominal pain, fever, diarrhea and weight loss. Radiological and endoscopic examination confirms the diagnosis, granulomas in the biopsy specimen are pathognomonic. In differential diagnosis ulcerative and ischaemic colitis have to be ruled out. Conservative therapy with prednisolone and salazopyrin is the method of choice, however, complications like small bowel obstruction, toxic megacolon and fistulae ask for surgical intervention.

[Diurnal variation of glucose tolerance and insulin secretion in man (author's transl)]

The present investigation was designed to determine whether the circadian rhythm of glucose utilization is based on a quantitatively different release of insulin and/or on changing secretory dynamics of the hormone. 22 healthy men received three oral glucose tolerance tests in the morning, afternoon and evening of the same day. The blood sugar levels in the afternoon and evening tests were significantly higher than those found in the morning tests. Also the plasma insulin response was higher in the afternoon than in the evening, but it showed a delayed rise and late peak response. In the evening the normal subjects responded as mild diabetics.