Mesohepatectomy for centrally located hepatocellular carcinoma: an appraisal of a rare procedure

BACKGROUND

For centrally located hepatocellular carcinoma (HCC), extended major hepatectomy is usually recommended, but the risk of postoperative liver failure is high when liver function is not sound. Mesohepatectomy (en bloc resection of Goldsmith and Woodburne's left medial and right anterior segments or Couinaud's segments IV, V, and VIII) is a rare procedure, so its role in treating HCC is unclear.

STUDY DESIGN

We retrospectively reviewed 364 patients who underwent a curative resection for HCC. Among them, 15 patients were treated by mesohepatectomy. Their nontumorous liver revealed cirrhosis in 11 and chronic hepatitis in 4. The mean tumor diameter was 12.8 cm. In 10 of the 15 patients, HCC also invaded adjacent organs. The operative results of another 25 patients with different disease extent who underwent extended major hepatectomy were compared.

RESULTS

The hepatic inflow occlusion time for mesohepatectomy was longer than for extended hepatectomy (p = 0.01). The mean operative blood loss, amount of blood transfusion, operating time, and postoperative hospital stay in the mesohepatectomy group were 2,450 mL, 1,100 mL, 7.9 hours, and 14.9 days, respectively. In the extended-hepatectomy group, the values were 1,863mL, 768mL, 5.8 hours, and 16.8 days, respectively (all p>0.05 compared with mesohepatectomy). No patient died after mesohepatectomy, but after extended hepatectomy there was one death from liver failure. The Union Internationale contre le cancer (UICC) TNM stages of patients who underwent mesohepatectomy were as follows: stage II in 1, stage III in 4, and stage IVA in 10. All patients who underwent extended hepatectomy presented with stage IVA disease. The 6-year disease-free and actuarial survival rates after mesohepatectomy were 21% and 30%, respectively. The 6-year disease-free survival rate after extended hepatectomy was 9% (p = 0.11 compared with mesohepatectomy).

CONCLUSION

Although mesohepatectomy is time-consuming, it is justified for selected patients with centrally located large HCC in a diseased liver.

Botulism: heart rate variation, sympathetic skin responses, and plasma norepinephrine

BACKGROUND

Botulism may involve the autonomic nervous system.

METHODS

We assessed the autonomic function of 6 botulism patients with heart rate variations, sympathetic skin responses, and plasma norepinephrine.

RESULTS

Two weeks after onset, all the patients had absent sympathetic skin response in the palm and sole. Compared with controls, the heart rate variation of botulism patients was significantly decreased at rest (3.1 +/- 1.2% vs. 20.9 +/- 2.0%, p = 0.0018) and during deep breathing (4.3 +/- 2.3% vs. 29.7 +/- 2.6%, p = 0.0018). The botulism patients had significantly lower plasma norepinephrine levels (supine 29.2 +/- 10.1 pg/ml vs. 257.5 +/- 65.8 pg/ml, p = 0.0018; standing 40.3 +/- 13.1 pg/ml vs. 498.5 +/- 85.6 pg/ml, p = 0.0018). The heart rate variation and sympathetic skin response was greatly improved 6 months after onset.

CONCLUSIONS

Heart rate variation, absence of sympathetic skin response, and low plasma norepinephrine are all manifestations of autonomic dysfunction in botulism patients.

Liver resection for hepatocellular carcinoma in octogenarians

BACKGROUND

Liver resection is risky in patients aged > or = 80 years. Because of short life expectancies and improved nonoperative modalities, the role of liver resection in octogenarians with hepatocellular carcinoma (HCC) is unclear.

METHODS

A retrospective review of the operative results of 260 patients with HCC between 1991 and 1997 was performed. According to the age at the time of operation, these patients were divided into 2 groups. Group 1 comprised 21 patients aged > or = 80 years, and group 2 comprised the other 239 younger patients. The backgrounds, pathologic features of the tumor, and operative results of the patients were compared.

RESULTS

Octogenarians had a higher incidence of associated medical diseases, a higher incidence of negative serum hepatitis B surface antigen, a lower alpha-fetoprotein level, and a higher indocyanine green retention rate. Although octogenarians had a longer postoperative hospital stay, there were no significant differences between the 2 groups regarding operative morbidity and mortality. The 5-year disease-free and actuarial survival rates for octogenarians and younger patients were 50.6% and 35.3% (P = .15) and 40.9% and 59.3% (P = .46), respectively.

CONCLUSION

Under meticulous preoperative assessments and postoperative care, liver resection for HCC is justified in selected octogenarians, with short- and long-term results comparable to those of younger patients.

Effect of stimulation of an upper limb on motor evoked potentials in lower limb muscles to transcranial magnetic stimulation in normal subjects and patients with thalamic infarction

The effects of conditioning stimulation of an upper limb on motor evoked potentials (MEPs) of relaxed muscles in both lower limbs were studied in 7 normal subjects and two patients with left thalamic infarction. A possible mechanism for the Jendrassik maneuver (JM) is that induced proprioceptive input ascends supraspinally to facilitate the descending volleys. In order to mimic the JM with a more controlled influence, we used an electrical conditioning (C) stimulation (4 times sensory threshold) delivered to the left index finger preceding the transcranial (T) magnetic stimulation at C-T intervals of 0-200 ms. The MEP facilitation of bilateral tibialis anterior (TA) and gastrocnemius medialis (GC) was within C-T 70-110 ms. The peak facilitation was at C-T 80 ms for ipsilateral TA (309%) and GC (405%) and at C-T 90 ms for contralateral TA (207%) and GC (283%). In the two thalamic infarction patients with right-sided sensory loss, the facilitation did not occur when the conditioning stimulation was delivered to the affected index finger. Therefore, it is likely that the peripheral volley must be transmitted supraspinally to facilitate MEPs of the lower limbs. This method for studying sensory facilitation is more quantitative and reproducible than the JM and technically better than other previously described methods for somatosensory conditioning.

Pilot evaluation of a nurse-administered carepath for successful colonoscopy for persons with spinal cord injury

Due to ongoing improvements in medical care, the life expectancy of persons with spinal cord injury (SCI) continues to improve and approach that of the able-bodied population. As the SCI population ages, cancer would be expected to increase as a cause of death. When a patient presents with occult fecal blood and anemia, colonscopy to the cecum is often pursued. It has been our experience that 80 percent of patients are found to have inadequate bowel preps resulting in suboptimal colonoscopy when the prep is attempted at home. Because of this, we developed a nurse-administered carepath necessitating a 48-hour admission for bowel prep and colonoscopy. The bowel prep consists of magnesium citrate, polyethylene glycol-electrolyte solution, and sodium phosphate/biphosphate enemas. Throughout hospitalization, the patient receives a clear liquid diet. Eighteen patients have been placed on the carepath. At the time of colonoscopy, all 18 were noted to have received an acceptable bowel prep allowing vizualization to the cecum. A description of the carepath and its benefits is presented.

The effects of chronic lead exposure on long-term depression in area CA1 and dentate gyrus of rat hippocampus in vitro

Long-term potentiation (LTP) and long-term depression (LTD), two forms of synaptic plasticity, are believed to underlie the mechanisms of learning and memory. Previous studies have demonstrated that low-level lead exposure can impair the induction and maintenance of LTP in vivo and in vitro. The present study was carried out to investigate whether the low-level lead exposure affected the induction and maintenance of LTD. Neonatal Wistar rats were exposed to lead from parturition to weaning via milk of dams drinking 0.2% lead acetate solution. Field excitatory postsynaptic potentials (EPSPs) were recorded in hippocampal slices in adult rats (50-65 days) to study the alterations of LTD in area CA1 and dentate gyrus (DG) of hippocampus following chronic lead exposure. The input-output (I/O) curves before conditioning in both areas showed no evident alterations in basic synaptic transmission between the control and lead exposure groups. In area CA1, the mean amplitude of EPSP slope in control rats (61+/-11%, n=15) decreased significantly greater than that in lead-exposed rats (78+/-8%, n=8, P<0.05) following low frequency stimulation (LFS, 1 Hz, 15 min), which lasted at least 45 min. In area DG, with application of the same LFS, the LTD was induced in control rats (72+/-22%, n=8), while the LFS failed to induce LTD in lead-exposed rats (100+/-26%, n=8). These results showed that chronic lead exposure affected the induction of LTD in both area CA1 and DG. The effect of lead on synaptic plasticity in area CA1 was also investigated. The alteration of the amplitude of LTP in hippocampal slices caused by lead was reexamined in order to compare with that on LTD (control: 189+/-23, n=5; lead-exposed: 122+/-12, n=10). The result demonstrated that low-level lead exposure could reduce the range of synaptic plasticity, which might underlie the dysfunction of learning and memory caused by chronic lead exposure.

Discordance between uterine cervical cytology and biopsy: results and etiologies of a one-year audit

To investigate the etiologies of discrepancies between cervicovaginal smear and corresponding cervical biopsy results, a total of 15,474 cervicovaginal smears were sampled in a one-year period. Among these, 427 patients were diagnosed with atypical squamous cells of undetermined significance (ASCUS), dysplasia, or malignancy. The screen positive rate was 2.8%. All of the positive cases had histologic follow-up. Forty-nine of the 427 patients had a discrepancy of at least two grades (the grades are divided to negative, ASCUS, mild dysplasia, moderate dysplasia, severe dysplasia and invasive carcinoma), between the cytologic and histologic diagnoses. The discrepancy rate was 11.5%. Ten of these discrepant cases had poorly-preserved slides or a not definitely final diagnosis. A total of 39 cases (79.6%) of discrepancy were reviewed in this study. In thirty (77%) of the 39 discrepant cases, the errors were cytologic and in 9 cases (23%) the errors were histologic. Cytologic error was the major cause of cytohistologic discrepancy. The etiologies of cytohistologic discrepancy included: cytologic interpretation error, 17 cases (44%); cytologic sampling error, 10 cases (25%); biopsy sampling error, 6 cases (15%); cytologic screen error, 3 cases (8%); and biopsy interpretation error, 3 cases (8%). The major etiology of cytohistologic discordances was cytologic interpretation error. In this retrospective study, we determined the etiologies of cytohistologic discrepancies. This information can be useful for improving diagnostic accuracy and the quality of patient care.

Conditioning effect on the long latency potentials in the lower limb to transcranial magnetic stimulation

OBJECTIVES

We used an electrical conditioning stimulation followed by transcranial magnetic stimulation (TMS) to facilitate the occurrence of long latency potentials (LLPs) in order to study the relationship between primary motor evoked potentials (MEPs) and LLPs in the lower limbs.

MATERIALS AND METHODS

The study group included 6 healthy subjects, 1 patient with right thalamic infarction, and 3 patients with spinal cord injuries. The subjects were subjected to electrical conditioning (C) stimulation delivered to the left big toe at 250 Hz in a train of pulses of 20 ms duration prior to TMS (T) from 0 to 150 ms at an increment of 10 ms. The surface electromyographic signals were recorded at the tibialis anterior and gastrocnemius medialis for 400 ms.

RESULTS

The C-T test facilitated both primary MEPs and LLPs with a pattern similar to the primary MEPs of its antagonist. There was no facilitation of the primary MEPs or LLPs in the affected limb of patients with thalamic or spinal cord lesions.

CONCLUSION

At appropriate C-T interval, LLPs could be consistently provoked by TMS. The LLPs were absent in the patients with thalamic infarction and spinal cord injuries. It suggests that LLPs might be provoked through a supraspinal control.

Fine-needle aspiration cytology of retroperitoneal extramedullary hematopoiesis: a case report

We report a 69 year-old man with left renal hilar tumor, which was incidentally detected and clinically suspected to be malignant. Interpretations of fine-needle aspiration (FNA) and frozen section of this tumor were not conclusive, and originally malignancy could not be ruled out. Later, correlation with the patient's history and bone marrow biopsy with cytological and histological pictures resulted in the diagnosis of a tumor of extramedullary hematopoiesis (EMH). This case shows that FNA cytology may be a useful method for diagnosing EMH. However, we also demonstrate the potential pitfall of misdiagnosing atypical megakaryocytes as malignant cells on FNA smears, or even in frozen sections, when clinical history and clinical data are not available. EMH should be considered in the differential diagnosis of patients with bone marrow disorders and mass lesions in extramedullary sites.

Intratumoral injection of rhenium-188 microspheres into an animal model of hepatoma

Intratumoral injection of 90Y microspheres is a potential alternative in the treatment of primary liver tumor. However, complicated preparation and lack of a gamma ray for imaging are the disadvantages of 90Y. In this study, we used 188Re, a generator-produced radioisotope with 155-keV gamma ray emission, to label microspheres. After intratumoral injection of 188Re microspheres into rats with hepatoma, biodistributions and survival times were analyzed.

METHODS

Twelve male rats with hepatoma were killed at 1, 24 and 48 hr (4 rats at each time point) after intratumoral injection of approximately 7.4 MBq 188Re microspheres. Samples of various organs were obtained and used to calculate the tissue concentrations. In addition, 30 male rats bearing hepatoma were divided into two groups (15 rats in each group) to evaluate survival time. Group 1 received intratumoral injection of 37 MBq 188Re microspheres, whereas Group 2 served as the control group and received an intratumoral injection of 0.1 ml normal saline only. Survival time was calculated from the day of injection to 2 mo after treatment.

RESULTS

Radioactivity in the tumor was very high throughout. Biological half-time was 170.8 hr. Radioactivity in the lung was 1.78% injected dose (i.d.)/g at 1 hr but declined rapidly over time. The concentration in the urine was approximately 6.14% i.d./ml after the first hour and rapidly declined thereafter. The concentrations of radioactivity in other organs, such as normal liver, muscle, spleen, bone, testis and whole blood, were quite low throughout the study. Twelve of 15 (80%) of rats survived over 60 days after intratumoral injection of 188Re microspheres, whereas only 4 of 15 (26.7%) survived more than 60 days after injection of normal saline only. The difference between the groups was significant (p < 0.05).

CONCLUSION

Rhenium-188 offers cost-effectiveness, on-site availability, short half-life, energetic beta particle, emission of gamma photons for imaging, easy preparation, easy clinical administration and apparent lack of radiation leakage from the treated tumor. Direct intratumoral injection of 188Re microspheres is extremely attractive as a clinical therapeutic alternative in hepatoma patients.

Impairment of long-term potentiation and paired-pulse facilitation in rat hippocampal dentate gyrus following developmental lead exposure in vivo

Neonatal rats were exposed to lead from parturition to weaning via the milk of dams drinking 0.2% lead acetate solution. The alterations of long-term potentiation (LTP) and paired-pulse facilitation (PPF) of hippocampal dentate gyrus in adult rats (90-115 days) following developmental lead exposure were studied in vivo. Input/output (I/O) function, paired-pulse facilitation (PPF), excitatory postsynaptic potential (EPSP) and population spike (PS) amplitude were measured in the dentate gyrus (DG) in response to stimulation applied to the lateral perforant path. The results showed that LTP was induced in control rats with an average PS potentiation of 321.1+/-50.0% (n=18), which was significantly greater than the increase in PS potentiation (173.5+/-30.0%, n=17, p<0.001) in lead-exposed rats after tetanizing stimulation. The mean EPSP potentiation increased to 172.4+/-27.0% (n=18) in control and 138.8+/-21.4% (n=17) in lead-exposed rats after tetanizing stimulation. The lead-induced impairment of LTP of PS potentiation was more serious than that of EPSP potentiation. Following pairs stimulation of perforant fiber at 250 microA and an interpulse interval (IPI) of 10-1000 ms, the average peak facilitation of PS was 211.3+/-25.0% (n=13) in control and 187.7+/-23.0% (n=11) in lead-exposed rats. The average facilitation period duration of PS was 243.0+/-35.8 ms (n=13) in control and 138.0+/-24.4 ms (n=11) in lead-exposed rats. These results suggested that developmental lead exposure in neonatal rats caused impairments in LTP and PPF of hippocampal dentate gyrus.

Rates of change in spinal bone density among Japanese women

To determine the rates of change in bone mineral density (BMD) at the spine in healthy Japanese women, longitudinal measurements of spinal BMD using dual X-ray absorptiometry were collected from 984 women over 17 years of age (mean age 51.6) at eight medical research centers. They were followed up for 20.9 months on average without any treatment influencing bone and calcium metabolism. Measurements of BMD obtained by two different scanners were converted into standardized BMD (sBMD) values. The multiple linear regression model predicts that spinal sBMD increases up to about 23 years of age: the estimated average rates of increases were 0.13%/year for women aged 20 years. After the age of 23, the sBMD began decreasing: the rates of loss increased by 0.045%/year for each year increase in age among premenopausal women. In perimenopausal women, the rate of loss was 2. 1%/year. In postnatural menopausal women, the rates of loss decreased exponentially with increasing years since menopause. The rates of loss increased by 0.04%/year for 1 kg decrease in body weight or by 0.1%/year for 1 kg/m2 decrease in body mass index. No significant differences in changes in sBMD were found between scanners and between centers after multiple adjustment. We conclude that the rates of change in spinal sBMD are associated with age in premenopausal women, and with years since menopause and weight or BMI in postmenopausal women. Caution is needed, however, when using data from different densitometers to evaluate rates in bone loss in multicenter trials.

Tumor angiogenesis and metastasis: correlation in invasive renal cell carcinoma

BACKGROUND

Experience suggests that tumor growth is dependent on angiogenesis. The intensity of angiogenesis in human cancer is reported to be predictive of the probability of metastasis in many types of cancer. The aims of this study were 1) to determine the relationship of microvessel density (MVD) in renal cell carcinoma to pathologic stage, and 2) to evaluate the role of MVD in metastasis.

METHODS

Paraffin-embedded tumor specimens were reviewed from 34 unselected patients with RCC who had undergone surgery from 1986 to 1990 at Taichung Veterans General Hospital. The pathology findings and clinical records were reviewed to note relationships between pathologic stage and whether or not metastasis had occurred. Specimens were studied from 16 cases (eight Stage I cancers, five Stage II and three Stage III) without metastasis and from 18 cases (two Stage I, six Stage II, six Stage III and four Stage IV) in which metastasis later developed. Microvessels were highlighted by immunostaining endothelial cells for factor VIII-related antigen. Microvessels were counted in a x-400 field (0.1885 mm2/field) in the most active areas of neovascularization.

RESULTS

The 16 patients without metastasis have survived for between 65 and 136 months (mean, 94.5 months), up to the present time. Of the 18 patients with metastasis, 15 died and three survived, with mean survivals of 42.8 months (range, 12-99 months). Mean overall MVD was 99.6 vessels; mean MVD was 98.5, 96.2, 109.3 and 90.0 in Stages I, II, III and IV tumors, respectively. Mean MVD was 99.3 in patients without metastasis and 99.9 in patients with metastasis.

CONCLUSIONS

MVD does not correlate with pathologic stage and is of no prognostic significance in renal cell carcinoma.

Cutaneous reflexes in patients with acute lacunar infarctions

Cutaneous reflex (CR) was measured in 15 patients with acute lacunar stroke and in 15 age- and sex-matched normal subjects. EMG activities were recorded from the first dorsal interosseous muscle with surface electrodes, rectified and averaged. Intensity of the stimulation on the index finger was four times the sensory threshold. Aided by audio- and visual-feedback monitoring, the subjects abducted the index finger. Side-to-side comparison was made on all the subjects. CR abnormalities were found in all of our patients. The early inhibitory (I1) and second excitatory (E2) components were attenuated in 11 of 15 patients. The I1-E2 interpeak amplitude (A2) was significantly reduced in all the patients. Prolonged latency of I1-E2 components was found to be pronounced in six of eight patients with sensory symptoms. Eight patients were followed up 1 month later. By that time, the abnormal CR had reversed to some degree in all of them. CR alternation was still present in two fully recovered patients. Our results implied a thalamic relay in the afferent limb of the CR. CR could be a valuable adjunct for assessing long tract dysfunction and monitoring functional recovery.

Long latency responses in pure sensory stroke due to thalamic infarction

OBJECTIVES

Our study was designed to clarify the role of the thalamus in the generation of the electrically elicited long-latency reflexes (LLR) in voluntarily activated hand muscles.

MATERIALS AND METHODS

EMG responses of the thenar muscles were evoked by electrical stimulation of the median nerve at the wrist at motor threshold intensity in 10 patients with acute pure sensory stroke due to thalamic infarction. Concomitant recording of somatosensory evoked potentials (SEPs) was performed. The subjects were asked to steadily abduct the thumb at 20-30% of maximal force against a force transducer. Rectified and averaged EMG activities were recorded.

RESULTS

The LLR II was missing completely or significantly attenuated in the majority of the patients (9 of 10), of whom 3 also had delayed latency. Abnormal SEPs were documented in 7 patients (7 of 10). In the follow-up, 5 patients had partial reversal of LLR II. LLR II was still pathological in 1 fully recovered patient.

CONCLUSION

Our results further confirm the transcortical generation of LLR II and imply that a thalamic relay is present in the afferent limb of the LLR.

Phentolamine effect on the spontaneous electrical activity of active loci in a myofascial trigger spot of rabbit skeletal muscle

OBJECTIVE

To investigate the effect of phentolamine, a sympathetic blocking agent, on the spontaneous electrical activity (SEA) recorded from a locus of a myofascial trigger spot (MTrS), equivalent to a human trigger point, in rabbit skeletal muscle.

DESIGN

Randomized control trial.

SETTING

A university medical laboratory.

PATIENTS OR OTHER PARTICIPANTS

Nine adult New Zealand rabbits.

INTERVENTION

In the experimental group phentolamine mesylate (1mg/kg) was injected into the external iliac artery, followed by flushing with normal saline. The control group was treated with normal saline instead of phentolamine using the same procedure.

MAIN OUTCOME MEASURES

SEA was recorded from multiple active loci of MTrSs in the biceps femoris muscle: initially SEA in the same locus was recorded before and immediately after phentolamine (or normal saline) injection; then SEA was recorded from 25 different active loci. The mean of the average integrated signal (AIS) of SEA was analyzed, comparing the effects of phentolamine and normal saline on SEA.

RESULTS

In the same active locus, the AIS of SEA showed statistically a linear decay with time after phentolamine injection, with a correlation coefficient of .56 at p < .05. However, no statistical relationship could be derived for the control group data with time by using regression analysis, probably because of large variations among the rabbits and movement artifacts during the experiment. In 25 different loci in the phentolamine group, the mean of the AIS of SEA (7.92 microV) was significantly lower than that of the control group (9.89 microV) at p < .05.

CONCLUSIONS

The results support the hypothesis that the autonomic nervous system is involved in the pathogenesis of myofascial trigger points. The application of the AIS as an evaluation index seems to be feasible in the quantitative measurement of SEA.

Prospective comparison of temperature guided microwave and radiofrequency catheter ablation in the swine heart

Microwave energy has been proposed as an alternative to radiofrequency energy for use during catheter ablation procedures. The purpose of this study was to prospectively compare, in an animal model, the lesion size associated with temperature guided catheter ablation using either microwave or radiofrequency energy. Eleven swine underwent catheter ablation with either radiofrequency (N = 4) or microwave energy (N = 7). In each animal catheter ablation was performed at 7-15 sites. At each site energy was delivered for 60 seconds using closed loop feedback temperature control to achieve a target temperature of 70 degrees C. Cardiac catheterization was performed before and after ablation. Animals were sacrificed approximately one month following the ablation procedure. Analysis of lesion size demonstrated that overall lesions created using radiofrequency energy were larger than those created using microwave energy. In the ventricle, lesions created using microwave energy were longer, but had a similar width and depth as those created using radiofrequency energy. An important relation was observed between the depth of lesions created using microwave energy and catheter stability, as evidenced by the temperature profile. Overall, lesions created using microwave energy are smaller than those created using radiofrequency energy. Catheter stability has an important impact on lesion size.

Rhenium-188 microspheres: a new radiation synovectomy agent

Radiation synovectomy is efficacious in controlling the symptoms of rheumatoid arthritis. However, the procedure is not widely used because of concerns about leakage of radiopharmaceuticals from the treated joints. Leakage can be minimized by selecting particles of an appropriate size. In this study, we labelled microspheres with 188Re and analysed its biodistribution after intra-articular injection in rabbits with antigen-induced arthritis. Gamma camera imaging was performed to quantify the mean retention of 188Re in the knees. The mean retention of 188Re was 98.7, 94.6 and 93.6% at 1, 24 and 48 h, respectively. The biodistribution data revealed very low radioactivity in all organs at different times, which suggests the leakage of radiotracer from the knee was negligible. Our preliminary results indicate that 188Re microspheres are a potentially effective radiopharmaceutical for radiation synovectomy.

Thoracic aortic aneurysm repair with endovascular stent-grafts

The purpose of the study was to describe the clinical experience is using endoluminal stent-grafts for the treatment of thoracic aortic aneurysms in high-risk patients. Patients with aneurysms of the descending thoracic aorta who were considered high surgical risks underwent evaluation for endoluminal repair. The prosthesis was constructed from Z stents covered with polyester fabric using dimensions based upon preprocedural computed tomography scans and angiography. Through a femoral arteriotomy or left retroperitoneal flank incision, a 22-24 Fr delivery catheter was inserted and advanced through the aorta to the target site under fluoroscopic guidance in the operating suite. The stent-graft prosthesis was deployed at the site of the aneurysm. 44 patients (36 male, 8 female; mean age 36 years) underwent stent-graft repair for thoracic aneurysms (mean diameter 6.3 cm). The deployment was technically successful in all cases, with complete aneurysm thrombosis in 88%. The 30-day perioperative mortality rate was 6.8% and 35-month actuarial survival was 82%. There were no cases of stent migration, surgical conversion or intraprocedural death. Paraplegia occurred in two patients who underwent simultaneous surgical infrarenal aortic aneurysm repair immediately followed by stent-graft placement for a coexisting thoracic aneurysm. The conclusion was that placement of endoluminal stent-grafts for repair of thoracic aortic aneurysms is technically feasible in high-risk patients in whom conventional surgery is contraindicated. Long-term studies are needed to determine protection against aneurysm rupture and patient survival.

A SPECT study of patients with gait apraxia without evidence of frontal lobe dysfunction

BACKGROUND

The pathogenesis of gait apraxia (GA) is unknown. Even though imaging studies provide excellent assessment of brain morphology, there is still a lack of congruous results. Single photon emission computed tomography (SPECT) using Tc-99m hexamethylpropyleneamine oxime (HMPAO) may show alterations in regional cerebral blood flow (rCBF) and provide indirect information about brain metabolism.

METHODS

We conducted a SPECT study of GA patients and evaluated the related cortical function. rCBF was assessed in 16 GA patients (15 male, one female; age range 65-79 years, mean 70.5 years) by SPECT using HMPAO. Mean HMPAO cortical or basal ganglia/cerebellum activity ratios were calculated. The regions of interest included the frontal lobe, parietal lobe and basal ganglia. A battery of GA tests and magnetic resonance imaging (MRI) of the brain were also performed in these 16 patients.

RESULTS

Nine of the patients had equilibrium disorder, and all 16 patients had locomotion disorder. The MRI findings were lacunar infarct (16/16 in basal ganglia, or 6/16 in thalamus), leukoaraiosis (4/16), enlarged ventricle (3/16), frontal lesion (3/16) and parietal lesion (1/16). Lower rCBF was noted in the frontal lobe (3/16), occipital lobe (1/16, thalamus (7/16) and basal ganglia (9/16). Though SPECT showed decreased rCBF in nine patients (9/16), mean cortical and basal ganglia regional uptake ratios in the patient group were not significantly different from values in the control group (cortical p = 0.0613; basal ganglia p = 0.0576, by Student's t-test).

CONCLUSIONS

Though only a small number of patients were studied, it was clear that brain SPECT and MRI did not show any significant abnormalities in the frontal or parietal lobes of patients with GA. Thus, the pathogenesis of GA and its related anatomic lesion should be further investigated.

Myofascial trigger points in intercostal muscles secondary to herpes zoster infection of the intercostal nerve

Chronic pain in the chest wall is a major complication after herpes zoster infection of intercostal nerves. It is usually difficult to control pain of such origin. Two cases are reported of postherpetic neuralgia after herpes zoster infection involving the intercostal nerves. Both patients had shooting, burning, aching, and localized pain in the muscle supplied by the involved intercostal nerves 1 to 3 months after onset. Compression palpation of a tender spot in one of these muscles induced a referred pain that followed the corresponding interspace, usually in the distal anterior direction. Local twitch responses could be elicited during injection of 0.5% or 1% lidocaine into one of these tender spots; the pain in the interspace was consistently eliminated immediately after injection. One patient had complete pain relief after three series of injections. The effect of pain relief for the other patient lasted for 1 to 2 weeks after the initial injection and lasted progressively longer (up to 2 months) after repeated injections. It appears that many of the tender spots formed in intercostal muscles after herpes zoster are myofascial trigger points that respond to injection with referred pain, local twitch responses, and immediate pain relief.

Ultraviolet-visible acousto-optic tunable spectroscopic imager for medical diagnosis

An ultraviolet to visible acousto-optic tunable filter was used to measure native fluorescence images from in vitro breast tissues at different wavelengths. Pseudocolor maps based on fluorescence images at two wavelengths were used to separate normal and abnormal regions in human breast tissues in vitro, providing diagnostic information. © 1998 Society of Photo-Optical Instrumentation Engineers.

Primary coexistent adenocarcinoma and choriocarcinoma of the stomach. A case report and review of the literature

We report a case of primary gastric choriocarcinoma with liver metastasis. The mixed histologic patterns included adenocarcinoma, undifferentiated carcinoma, and choriocarcinoma. Immunohistologic staining for the beta-subunit of human chorionic gonadotrophin (beta-HCG) showed positive results in the choriocarcinoma, adenocarcinoma, and normal mucosal gland. However, positive HCG cells were present at different intensities in the choriocarcinoma, adenocarcinoma, and normal mucosal gland. The level of HCG was significantly increased in serum. This unusual tumor probably resulted from dedifferentiation of a primary adenocarcinoma or developed directly from the mucosal glands.

Frozen-section diagnosis in surgical pathology: a quality assurance study

In a quality assurance study we reviewed one thousand four hundred and forty-three consecutive frozen sections performed at department of pathology, VGH-TC from June 1995 to July 1996. The diagnostic accuracy was 92.6%. The diagnosis was deferred in sixty-eight cases (4.7%). False positive for malignant tumor was made in two cases (0.14%) and false negative diagnosis for malignancy in thirty-seven (2.56%). The inaccurate diagnosis was mainly in samples taken from the brain, female breast, and thyroid. Incorrect diagnoses were mainly due to interpretation of the pathologic findings (71.8%), followed by gross sampling (15.4%) and microscopic sampling (12.8 %). Some of the lesions were difficult to diagnose even in permanent sections. Technical skill and diagnostic expertise are essential for frozen diagnosis. We suggest that an accuracy survey of frozen section be periodically performed in every pathology department as part of its quality assurance program.