Paraurethral cyst as an unusual cause of acute urinary retention. A case report

Acute urinary retention occurs rarely in women. Previously reported causes include anatomic defects, perineal pain, behavioral disturbances and psychiatric disorders. A patient presented with acute urinary retention secondary to an infected paraurethral cyst.

Comparative study of different iron-chelating agents in cold-induced brain edema

Increasing numbers of reports demonstrate the importance of iron and oxygen free radicals in brain injury and brain edema. We investigated the protective effects of three different ferric and ferrous iron-chelating agents on cold-induced brain edema. Vasogenic brain edema was produced by a cortical freezing lesion. Thirty-eight cats were separated into five groups: Group 1 (N = 8): normal control group without lesion; Group 2 (N = 8): untreated group; Group 3 (N = 8): deferoxamine (extracellular and intracellular ferric iron chelator)-treated group; Group 4 (N = 8): 2,3-dihydroxybenzoic acid (extracellular ferric iron chelator)-treated group; and Group 5 (N = 6): 2,2-bipyridine (intracellular ferrous iron chelator)-treated group. In Groups 3, 4, and 5, each agent was administered intravenously 15 minutes before lesion production and 60 minutes later. Animals in Groups 2, 3, 4, and 5 were killed 6 hours after lesion production. Brain water content in 8 sampling areas was measured by the specific gravity method. Blood-brain barrier disruption was assessed by the spread of Evans blue dye measured by planimetry. Brain water contents and Evans blue dye extravasated areas were significantly reduced in Groups 3 and 5 in comparison to Groups 2 and 4. These data suggest that both ferrous and ferric iron-chelating agents, which can penetrate the cell membrane and, presumably, act intracellularly, are effective in reducing cold-induced brain edema.

Local cerebral glucose abnormalities in mild closed head injured patients with cognitive impairments

Mild-moderate closed head injury (CHI) can be followed by neuropsychological impairments in recent memory and attention, despite the absence of discernible structural abnormalities in a significant number of patients. To determine whether CHI may result in cerebral glucose metabolic abnormalities, we used fluorodeoxyglucose (FDG) technique with PET imaging to measure local cerebral metabolic rates for glucose (LCMRGlu) in three CHI patients and three matched normal controls. The CHI patients were between 3-12 months post-injury. All had deficits in attention and recent memory shown by neuropsychological testing. CT, MRI, EEG and drug screens were negative at the time of PET scanning. Subjects were engaged in a vigilance task throughout the initial 30 min following FDG administration. Group comparisons were made using t tests. There were no significant group differences found in global glucose metabolic rate. Nevertheless, the CHI group exhibited significantly decreased LCMRGLu in medial temporal, posterior temporal, and posterior frontal cortices, as well as in the left caudate nucleus. LCMRGlu was significantly increased, relative to controls, in anterior temporal and anterior frontal cortices. These results suggest that CHI patients can have regional glucose metabolic abnormalities, indicative of altered neuronal function, despite the absence of discernible anatomic abnormalities.

Oxygen free radicals in the genesis of traumatic and peritumoral brain edema

This study evaluates the effect of superoxide dismutase, a scavenger of oxygen free radicals, on peritumoral and cold injury edema. Vasogenic brain edema was produced in 39 cats by a standardized cortical freezing lesion. Peritumoral edema was produced by the transplantation of VX2 carcinoma cells into the brain of New Zealand White rabbits. Detection of superoxide radicals was studied by topical application of nitroblue tetrazolium to the cortical injury and by incubation of the VX2 carcinoma cells. The animals were treated with free superoxide dismutase (SOD) and polyethylene glycol superoxide dismutase (PEG-SOD). The following groups were studied: 1) control, 2) untreated tumor group, 3) tumor group treated with PEG-SOD, 4) a group treated with PEG-SOD before injury, and 5) a group treated with free SOD after injury. Brain edema was evaluated by measurement of specific gravity and planimetry study of the spread of Evans blue dye. Preliminary data indicate that superoxide radicals are present in the brain after cold injury and in the cytoplasm and nucleus of VX2 carcinoma cells. Free SOD and PEG-SOD had no beneficial effect upon the vasogenic brain edema produced in either model. It is concluded that intracellular uptake of SOD may be one of the factors necessary for an effect upon either form of edema.

Placebo responses to medical device therapy for pain

Placebo response to a functionless machine was tested in 58 patients with chronic pain. Thirteen discontinued treatment before the planned trials were complete: 5 did so because sham therapy worsened their pain. Forty-five patients completed three trials of treatment with a magnetic device, one trial of which was a sham. Thirteen percent of patients undergoing sham therapy experienced relief of pain, improved range of motion, and decrease in muscle spasm. Eleven percent of the sham trials resulted in significant increase in pain. The placebo/nocebo response to sham therapy with a device is similar to that previously reported for prolonged drug treatment, but is lower than the placebo rate for short-term medication trials.

Quantification of thermal asymmetry. Part 2: Application in low-back pain and sciatica

Temperature differences between the lower extremities were measured using a computerized thermometric scanning system in order to compare the degree of thermal asymmetry in 144 patients with low-back pain. The patients displayed highly significant thermal asymmetries, with the involved limb being cooler (p less than 0.001). When asymmetries exceeded 1 standard deviation from the mean temperature of homologous regions measured in 90 normal control subjects, the positive predictive value of thermometry in detecting root impingement was 94.7% and the specificity was 87.5%. These values indicate that calculation of temperature asymmetry is particularly effective in evaluating reported pain in psychosocially affected patient populations in whom the chance of positive myelography or impaired root function is low. In this group of patients, thermometric study provides physicians with important information for proper decision making. The test can be performed to avoid more invasive and probably less revealing diagnostic or exploratory surgical procedures.

Schwannoma of the medulla oblongata. Case report

A case of intraparenchymal schwannoma of the medulla oblongata is presented. The radiographic and pathological characteristics of this rare tumor are discussed, and the world literature regarding intracerebral intraparenchymal schwannomas is reviewed. The current etiological theories of these intra-axial nerve-sheath tumors are reviewed. The importance of early identification and differentiation of these potentially curable tumors from malignant glial tumors is emphasized.

Clinical features of the failed-back syndrome

This study comprises 78 patients who were treated for chronic back pain at a multidisciplinary, multimodal pain treatment center. These patients were selected from 494 patients examined by the authors because all of their previous medical records, operative notes, and imaging studies were available for review. The records and imaging studies were reviewed independently by a neurosurgeon and an orthopedist, and a retrospective decision was made concerning the historical and physical findings correlated with imaging studies in order to provide justification for the intervention. At the time of admission to the pain treatment center, 16 patients had no physical abnormalities that would explain their back complaint and 16 patients exhibited minor postoperative changes insufficient to cause disabling pain. Twenty-seven patients suffered from a complication of previous surgery, 13 had spondylotic disease, and in six a new diagnosis was established. Comprehensive psychiatric evaluation of the 78 patients revealed that 10 patients had a definitive psychiatric diagnosis, 34 were diagnosed as having a maladaptive personality disorder, and 34 had a normal pre-pain personality. Sixty-seven patients suffered from reactive depression. Fifty-four patients were taking medications at doses higher than usually prescribed, 58 misused narcotics, nine had drug addiction, and 54 were suffering withdrawal symptoms. Of the 78 patients, 64 underwent a total of 171 operations, an average of 2.6 per patient. The authors applied the clinical criteria approved by the American Association of Neurological Surgeons and the American Academy of Orthopedic Surgeons for selection of surgery or chemonucleolysis in the treatment of the herniated disc to these patients. Preoperative imaging studies were normal or demonstrated nonspecific degenerative disc disease in 52 patients. Twenty-six patients had a diagnosis based on radiological findings that warranted surgery. Clinical criteria justifying intervention were met in 25 patients and not met in 53. Imaging and clinical criteria for a second operation were met in 18 (40%) of the patients. After the second operation all patients met the criteria: subsequent surgery was necessary to treat effects of an earlier operation in 73%. These data indicate that many of these patients with failed-back syndrome underwent an original operation based on a persistent complaint of pain, frequently coupled with an underlying psychiatric abnormality, although they did not meet the criteria generally accepted by neurosurgeons for intervention at the time of first surgery.

Perfluorochemicals as gastrointestinal contrast agents for MR imaging: preliminary studies in rats and humans

The ability to distinguish bowel from other intraabdominal structures is essential for the accurate diagnosis of intraabdominal disease with MR. Because perfluorochemicals have no protons, they cause no MR signal. Since they are immiscible with water, they create a signal void in bowel independent of bowel contents and thus are suitable as oral contrast agents. Furthermore, they are tasteless and odorless and have no side effects. We evaluated the use of perfluorochemicals by performing MR scans of the abdomen in rats after the oral administration of unemulsified perfluorohexylbromide or perfluoroctylbromide. Since the latter is approved as an investigational drug for oral use in humans, two volunteers were also studied. Both compounds created signal void in the bowel of both rats and human subjects allowing identification of the gastrointestinal tract. The results suggest that these compounds have potential as oral contrast agents for MR imaging.

Cerebellopontine angle lipoma

Cerebellopontine angle lipomas are rare lesions that differ from other intracranial lipomas in that they typically present with slowly progressive focal signs and symptoms identical to those of other tumors of this location, and by their propensity for intimate involvement of the adjacent cranial nerves. The lipomas in this study demonstrated this tendency to splay apart and infiltrate the cranial nerves, with the fatty tissue adjacent to the nerves invariably containing portions of the cranial nerves. Hence, the dissection of the adipose tissue from the nerves led to greater than anticipated postoperative neurologic deficits. Therefore, minimal excision of tumor is recommended to achieve decompression. Since preoperative evaluation does not distinguish with certainty this lesion from others more common to this location, intraoperative examination of frozen sections is required to confirm the diagnosis.

Aging in the nervous system

This review of the effects of aging on the nervous system covers functional changes, such as slowing of reaction time; behavioral and psychological changes; physiological changes in the brain; and pathological changes. The author discusses the sensory processes in relation to the neurological examination. Dementia due to Alzheimer's disease, normal pressure hydrocephalus, and other causes is also discussed.

Visual function following optic canal decompression via craniotomy

Visual function was assessed in 15 eyes of 11 patients who underwent unilateral (seven patients) or bilateral (four patients) optic canal decompression for presumed compressive optic neuropathies. Both immediate and long-term postoperative vision was evaluated in all eyes. Over 90% of the eyes that had undergone nerve decompression had either the same or improved visual acuity and visual field immediately following surgery. In this group of patients there were no deaths and there was only one postoperative complication, a transient dysphasia caused by an epidural hematoma that was evacuated. Long-term follow-up evaluations revealed that most of the eyes retained their immediate postoperative visual function or showed gradual visual improvement with time. The results of this series as well as a review of the available literature indicate that optic canal decompression via craniotomy can be a safe procedure and that it appears to have lasting visual benefit in many patients.

Specific enhancement of intra-abdominal abscesses with perfluoroctylbromide for CT imaging

Perfluoroctylbromide (PFOB), a radiopaque reticuloendothelial system contrast media for computed tomography, has been shown to accumulate in macrophages. In the current study PFOB was tested in rabbits as an abscess imaging agent. Two abscesses were induced in each of 24 rabbits, one in the liver and the other in the peritoneal cavity. CT of the rabbit abdomen was performed four days later, two days after the administration of 5 gm/Kg of PFOB to 12 of these rabbits. The average enhancement of the wall of liver abscesses was by 140 Hounsfield units (HU) relative to the enhanced liver and peritoneal abscesses by 135 HU relative to the control group. This enhancement was secondary to the intense accumulation of PFOB filled macrophages in the abscess wall. In those rabbits where the liver abscess ruptured, the edges of the peritoneal collections enhanced by 147 HU. Regions of inflammation prior to liquifaction enhanced considerably. These areas could not be detected in the animals not receiving PFOB. Though the liquified center of liver abscesses could be seen in the absence of PFOB, none of the peritoneal abscesses could be detected in the animals not receiving PFOB. In contradistinction, all peritoneal abscesses enhanced considerably following PFOB allowing their prospective localization. In conclusion, PFOB accumulates in abscess walls and areas of inflammation producing marked CT enhancement of liver and peritoneal abscess collections. This enhancement allowed the differentiation of peritoneal abscess collections from adjacent bowel.

Perfluoroctylbromide as a blood pool contrast agent for liver, spleen, and vascular imaging in computed tomography

Perfluoroctylbromide (PFOB) in emulsion form was tested as a blood pool imaging agent for computed tomography (CT) in five animals (three dogs and two pigs). Computed tomography of the kidneys, liver, spleen, and mediastinum was performed in the control state and at various time intervals after the end of PFOB infusion. The attenuation coefficient of the vascular space increased by 117 Hounsfield units (HU) (range 105-128 HU), the liver by 54 HU (range 43-70 HU), and the spleen by 77 HU (range 69-86 HU) 30 to 50 min after the end of PFOB infusion, 5 ml/kg. The vascular space enhanced by 25 HU for every g of PFOB/100 ml of blood and remained at almost a constant level for hours after the end of infusion. In conclusion, PFOB emulsion, in addition to hepatosplenic enhancement, produces prolonged and substantial opacification of the vascular space, allowing CT imaging of the heart and vascular structures minutes to hours after the end of infusion.

Electrocorticography: information derived from intraoperative recordings during seizure surgery

The findings of 100 consecutive electrocorticographies in 94 epileptic patients were reviewed. Most of these patients underwent temporal lobectomies. A well defined and circumscript cortical spike focus was found in only 28 tracings whereas multiple sub-foci of spike activity or dissipated areas of spiking were demonstrated in 46 recordings. Cortical spike activity was minimal in 14 and absent in 12 tracings. Additional one-lead depth electrodes (inserted mainly into amygdala and hippocampus) yielded rather little information in contrast to the wealth of information derived from chronic multiple-leads depth implants prior to surgery. The frequent occurrence of dissipated spike foci suggests that, in partial epilepsies (and especially in temporal lobe epilepsy), epileptogenic zones are more widespread than one would expect from the scalp EEG recordings. These findings lend support to the use of en-bloc removal of large portions of an affected lobe.

Stimulation of the peripheral nervous system for pain control

Transcutaneous stimulation is a proven effective way to relieve pain. Its optimal use requires an accurate patient diagnosis. Treatment of pain as a symptom only is likely to fail. There must be a careful psychosocial evaluation, for the majority of patients who come to the doctor complaining of pain have major psychological, social, or behavioral factors that are most important in the genesis of the complaint. Drug abuse must be corrected. Related symptoms, such as anxiety and depression, must be treated. Then, a thorough trail of transcutaneous stimulation is mandatory. A desultory use will undoubtedly lead to failure. This trial must begin with patient education by experienced personnel. Then the electrodes must be properly applied, and there must be a regular follow-up of stimulation to be certain the patient is utilizing it correctly. The patient must be supported through an adequate trial which should extend over 2-4 weeks before purchase of the device is contemplated. Furthermore, all related nursing and physician personnel must be educated in the proper use of the technique. The uninformed professional who denigrates the therapy is a very effective deterrent to appropriate use. In this situation, transcutaneous electrical stimulation will be of great value in the treatment of acute musculoskeletal injury and acute postoperative pain. It will be effective in the treatment of peripheral nerve injury pain, chronic musculoskeletal abnormalities, chronic pain in the patient who has undergone multiple operations upon the low back and neck, visceral pain, some of the reflex sympathetic dystrophies, and postherpetic neuralgia. Stimulation will not help a complaint which is psychosomatic in origin. It will not influence drug addiction. It is not likely to be useful in any situation where secondary gain is important. The metabolic neuropathies, pain of spinal cord injury, and pain from cerebrovascular accident will not respond frequently enough to warrant more than hopeful trials. The technique is inexpensive, places the patient in control of his own pain, and has no known serious side effects. Its widespread application awaits the development of reasonable systems to provide this service to physicians and patients. Stimulation-induced analgesia deserves a place in the armamentarium of every physician dealing with the complaint of pain.

Perfluorochemicals as liver- and spleen-seeking ultrasound contrast agents

In this study, Fluosol-DA, 20 per cent (composed of perfluorodecalin and perfluorotripropylamine) was tested as a liver-specific ultrasound contrast agent. Twelve normal rabbits were scanned, utilizing the Picker Microview (10 MHz), prior to and two days following the intravenous administration of 24 ml/kg of Fluosol (or 4.8 g/kg of perfluorochemicals) emulsion to ten of the rabbits and 24 ml/kg of Ringer's solution to two rabbits as control. In all ten rabbits given Fluosol, liver echogenicity increased relative to that of the kidney, whereas the liver remained less echogenic than the kidney in the two rabbits given Ringer's solution. Four independent reviewers correctly identified all rabbits that received Fluosol and both rabbits that received Ringer's solution. It is demonstrated that, similar to PFOB, Fluosol serves as an echogenic contrast material for ultrasound and opacifies the normal rabbit liver.

Perfluoroctylbromide: a reticuloendothelial-specific and tumor-imaging agent for computed tomography

Perfluoroctylbromide (PFOB) was evaluated as a liver/spleen-specific and tumor imaging agent in 30 rabbits implanted with VX2 tumors. Computed tomographic (CT) scanning of all rabbits was performed after sacrifice. Half of the animals were given 5 ml/kg of PFOB emulsion intravenously 48 hours prior to sacrifice. Twenty rabbits were used for anatomic correlation and ten for histologic analysis. PFOB concentration was measured in normal liver and spleen in eight rabbits at two days, in six rabbits at seven days, and in six rabbits at 14 days after PFOB administration (5 ml/kg, intravenously). PFOB increased the CT numbers of the liver by 49 HU and the spleen by 250 HU. More important for diagnostic purposes, PFOB produced dense enhancement of the rim of the tumor. The density of the rim of the tumor was increased by 102 HU as a result of accumulation of PFOB in macrophages at the periphery of the tumor. The half-life of PFOB in the liver and the spleen was approximately five days.

A new, treatable source of recurrent meningitis: basioccipital meningocele

A 19-month-old boy suffered eight episodes of bacterial meningitis. During the ninth episode a meningocele of the basioccipital clivus communicating with the nasopharynx was discovered. Identification of the organism causing the episodes of meningitis was not helpful in pointing to the site of this congenital anatomic defect. Surgical closure of the defect has prevented further recurrences.

Perfluoroctylbromide: a liver/spleen-specific and tumor-imaging ultrasound contrast material

The effect of perfluoroctylbromide (PFOB) on liver and tumor echogenicity was evaluated in rabbits. The echogenicity of the kidney, which is not affected by PFOB, was used as the basis for comparison in the liver studies. For the liver echogenicity study, sonography was performed on four rabbits, two with PFOB and two without PFOB, and four rabbits prior to and following the intravenous administration of 5 ml/kg PFOB. All livers were equal to or less echogenic than kidney in the control animals. All livers became more echogenic than kidney two days after administration of PFOB. The effect of PFOB on tumor echogenicity was evaluated in 18 rabbits with VX2 tumor implanted in the liver. Ultrasound studies of all rabbits were performed by the same physician before and two days after half the rabbits had received PFOB (5 ml/kg intravenously). The reviewers correctly identified all rabbits that received PFOB by visualization of an echogenic rim around the hepatic tumors.

Sleep spindles recorded from deep cerebral structures in man

The depth and scalp EEG findings in 73 patients with intractable epileptic seizure disorder and in 14 patients with intractable pain were reviewed; stress was laid on the area of earliest spindle activity. It was found that sleep spindles frequently occurred first in frontal depth leads and especially in the superior frontal region (supplementary motor region). In some cases, spindles in frontal depth leads occurred while the patient showed early drowsy activity or even waking activity (with posterior basic rhythm) in the scalp leads. In patients with thalamic implants, spindles tended to appear on the thalamus before appearance on the scalp. The general rule that sleep onset (NREM) is characterized by the appearance of spindles is valid for the scalp EEG only. Deep spindle activity occurs much earlier and probably requires a certain degree of synchronization before spindle activity is noticeable in scalp leads. The superior frontal region is likely to be the starting point of spindle activity.

CT determination of renal and hepatic microvascular volumes in experimental acute renal failure

Alterations in renal blood flow are considered to play an important role in the pathogenesis of acute renal failure. Most techniques designed to assess organ blood flow and microcirculatory disturbances are relatively invasive and cumbersome. This study describes a noninvasive method for the determination of an organ's fractional vascular volume (FVV)-the fraction of an organ occupied by blood vessel lumen. It utilizes computed tomographic (CT) scanning and a contrast agent, perfluoroctylbromide (PFOB), which remains intravascular and is not excreted by the kidney. Acute renal failure (ARF) was induced in rats by intraperitoneal injection of glycerol (5 g/kg). CT scans of kidneys, liver, and heart were performed prior to and following intravenous administration of PFOB. FVV of kidney and liver were calculated prior to induction of ARF and at selected time periods following ARF (20-50 minutes and 60-120 minutes). FVV of the kidney decreased significantly 20-50 minutes following ARF and had returned to control values at 60-120 minutes. Renal histologic abnormalities were more severe at the later time period. Thus, early alterations in blood flow precede pathologic abnormalities in the kidney following glycerol-induced ARF. Determination of an organ's fractional vascular volume is a simple noninvasive technique which provides useful information on the microcirculation during the course of experimental disease.

Perfluoroctylbromide contrast enhancement of malignant neoplasms: preliminary observations

Fluorocarbons have been used for years as propellants in aerosol sprays. Because of their ability to transport oxygen, perfluorocarbon compounds have been more recently used in artificial fluid respiration. Monobrominated perfluorocarbon compounds are radiopaque and have low enough vapor pressures to be tolerated in biologic systems. Microemulsions of these compounds have been detected in mouse and rat neoplasms and appear to be located within macrophages. In this study of the potential usefulness of these compounds for radiographic contrast enhancement, rabbits with V2 carcinoma thigh implants received either a high-dose (10--12 ml/kg) or a low-dose (2 ml/kg) emulsion of perfluoroctylbromide intravenously. Dense contrast enhancement of some of the V2 carcinomas was demonstrated by both computed tomography and conventional radiography. Four of the five rabbits in the high-dose group died within 9 days but all six rabbits in the low-dose group survived beyond 9 days. Death in the high-dose group was associated with pulmonary consolidation and anesthesia although some animals had extensive V2 metastases. These compounds have some interesting potential applications in imaging, pending further study of their toxicity.

A comprehensive model for the study and therapy of pain: Johns Hopkins Pain Research and Treatment Program

The Johns Hopkins Pain Research and Treatment Program is based upon individual diagnosis, psychiatric evaluation, and individualized therapy. This is done within the framework of a concurrent program involving neurosurgeons, consulting physicians, psychiatrists, clinical psychologists, social workers and specialized nurses. The basic theme is self-help and self-responsibility. Drug withdrawal is mandatory, and an emphasis is placed upon psychotherapeutic techniques. Pain relieving procedures are available and utilized in a small number of patients.

Electrical stimulation of the spinal cord and peripheral nerves for pain control. A 10-year experience

Patients who underwent implantation of dorsal column stimulators from 1970 to 1973 were reviewed 7-10 years following stimulation. The number who achieved satisfactory pain relief was not significant. The criteria for selecting these patients were reviewed utilizing those now used in 1980. 50% of the patients originally selected would now be rejected for psychological or drug-related reasons. This long-term evaluation indicates no benefit to the patients treated with spinal cord stimulation. However, it appears that psychological factors were the most important reasons for failure. A smaller group of patients studied for 3-5 years following implantation of epidural spinal cord stimulators achieved a 70% pain control rate. Selection factors that explain these differences are discussed.

Effects of pressure on cerebrospinal fluid formation: nonsteady-state measurements in dogs

Effects of pressure on cerebrospinal fluid (CSF) formation were studied in dogs with a recirculatory spinal perfusion tracer clearance technique that does not require steady-state conditions. The data permit statistical analysis of the relationship between the rate of CSF formation and pressure for individual animals. Most animals showed no statistical relationship between CSF formation and intracranial pressure (ICP) and/or cerebral perfusion pressure (CPP). In this study, a disturbance of cerebral blood flow (CBF) autoregulation may have been present in five animals on the basis of CPP reductions, and four of this latter group showed formation to decrease with increasing ICP. It is suggested that CSF formation is normally pressure insensitive. With impaired autoregulation of CBF, formation may follow CBF and CPP passively.

Briquet syndrome in a man with chronic intractable pain

A 51-year-old man was admitted for evaluation and treatment of scrotal pain of 20 years' duration following unilateral orchiectomy for right testicular injury. Past attempts had failed to provide definitive or persistent relief. Physical examination and investigations were unremarkable. Psychiatric assessment revealed an angry, depressed man with a drasmatic, hypermasculine manner and hysterical and obsessive personality traits. Review of systems with a structured interview indicated that the patient had numerous medically unexplained symptoms and that he fulfilled both the Feighner and the Diagnostic and Statistical Manual of Mental Disorders 3rd edition (DSM-III) diagnostic criteria for Briquet syndrome. The case is important because it demonstrates the usefulness of recognizing Briquet syndrome in patients with the single presenting complaint of chronic, intractable pain, and the fact that Briquet syndrome, commonly considered a female disorder, can occur in men regardless of sexual orientation and in the absence of expected compensation. In addition, the case confirms the utility of a structured interview and defined criteria for making the diagnosis of Briquet syndrome.

Experiments with radiopaque perfluorocarbon emulsions for selective opacification of organs and total body angiography

Emulsions of radiopaque perfluorocarbon with small particle size were prepared by sonication and concentrated by centrifugation. The emulsions were well tolerated when given intravenously to rats in a dose up to 20 ml/kg. Whole-body angiograms were obtained for up to 6 hours after injection with visualization of vessels smaller then 1 mm. Hepatosplenograms were obtained after 2 hours and for several days after injections of radiopaque perfluorocarbon. Contrast enhancement was also seen in the myocardium, ovaries, adrenal glands, and intestines with brominated perfluorocarbon emulsions.

Percutaneous lumbar medial branch neurotomy: a modification of facet denervation

Percutaneous lumbar medial branch neurotomy is a technique for facet denervation in which the target is specifically the medial branch of the dorsal ramus. The radiology of the technique is illustrated, and the technical aspects of the procedure are described. The accuracy of previous techniques for facet denervation as compared with medial branch neurotomy is reviewed in a comparative analysis of radiographs illustrating the various techniques. It is suggested that the greater accuracy of medial branch neurotomy will permit a more adequate trial of the rationale and efficacy of facet denervation.

Reduction of postoperative pain and narcotic use by transcutaneous electrical nerve stimulation

Transcutaneous electrical nerve stimulation (TENS) was evaluated as a postoperative analgesic. Patients undergoing lumbar spine operations, hip surgery, and gynecological laparotomies were studied. Sterile electrodes, placed near the incision immediately after operation, were connected to a continuously operating stimulator for 48 hours after operation. Results from 46 experimental patients demonstrated that TENS could reduce the demand for postoperative narcotics in a group of patients who had not used narcotic analgesics before operation. No significant benefit was observed for patients who had used narcotics prior to operation.

Dynamics of cerebral edema. The role of an intact vascular bed in the production and propagation of vasogenic brain edema

Brain edema was produced in cats by a standardized cortical freezing lesion. With a careful microsurgical tehnique, the injured cortex was removed as a single piece, either immediately after induction or at 2, 4, or 8 hours after lesion production. The injured brain was either discarded or replaced in its bed. Brain edema and the defect in the blood-brain barrier were assessed by determining percent dry weight, increase in volume of white matter, and spread of Evans' blue by planimetry. The results indicate that 1) if the lesion is removed immediately after production, formation of the expected vasogenic brain edema is completely abolished; 2) replacement of the frozen brain is unable to induce significant increase in permeability of the surrounding blood-brain barrier or a significant amount of brain edema; and 3) if the lesion is removed at 2, 4, or 8 hours with or without replacement, advancement of the edema front and increase in the amount of edema is stopped. It appears that an intact vascular bed is necessary for the extracellular fluid component of brain edema, and that no edemagenic factors exist within the injured brain in this model that influence either the production or propagation of the increased extracellular fluid volume.

Strategic planning has market orientation

A key element in the strategic planning process is active involvement of the hospital's key personnel so that each has a commitment to the ultimate plan.

Comparison of radiopaque perfluorocarbon and Ethiodol in lymphography

Lymphangiography was performed on 40 adult cats, 39 dogs, 20 rabbits, and 12 rats of mixed sex using Ethiodol or radiopaque perfluorocarbon (BPC). Ethiodol was more radiodense than RPC, but imaging of lymph channels and nodes was satisfactory with the latter. RPC could be infused rapidly, while Ethiodol infusion was time consuming. RPC was biologically inert; Ethiodol produced both local and systemic inflammatory reactions. The lymph node distribution with RPC was more uniform and persisted for longer periods. It was concluded that RPC was an improvement over Ethiodol for lymphangiography.