Fibulin Levels in Autosomal Dominant Polycystic Kidney Disease and Its Relationship to Arterial Stiffness

BACKGROUND

The objective of the present study was to evaluate fibulin 1 levels in different stages of patients with autosomal dominant polycystic kidney disease (ADPKD) and investigate possible connections between fibulin-1 and arterial stiffness.

METHODS

For this cross-sectional study, we included 74 patients with ADPKD (mean age, 50.92 ± 15.70 years) and 32 healthy controls (mean age, 49.53 ± 7.32 years). Patients with ADPKD were classified based on CKD epidemiology collaboration (CKD-EPI) equation assessments of estimated glomerular filtration rate (eGFR). Blood levels of fibulin 1 and creatinine levels were analyzed. We measured brachial artery PWV (baPWV), augmentation index (AIx), and pulse pressure (PP) for the assessment of arterial stiffness and systolic and diastolic blood pressures (SBP and DBP, respectively).

RESULTS

Fibulin 1 was significantly higher in the patient group (p < 0.001). SBP, DBP, MAP, PP, and baPWV levels were also significantly higher in the patient group. A statistically significant positive correlation was found between fibulin 1 and creatinine (r = 0.377, p = 0.001). No significant correlation was found between the fibulin 1 levels and age, SBP, DBP, MAP, baPWV, and AIx.

CONCLUSIONS

Plasma concentrations of fibulin 1 increased in patients with ADPKD. Arterial stiffness measured by baPWV increased in patients with ADPKD, but it was not related to fibulin 1 levels.

Historical epidemiology of hepatitis C virus in select countries-volume 4

Due to the introduction of newer, more efficacious treatment options, there is a pressing need for policy makers and public health officials to develop or adapt national hepatitis C virus (HCV) control strategies to the changing epidemiological landscape. To do so, detailed, country-specific data are needed to characterize the burden of chronic HCV infection. In this study of 17 countries, a literature review of published and unpublished data on HCV prevalence, viraemia, genotype, age and gender distribution, liver transplants and diagnosis and treatment rates was conducted, and inputs were validated by expert consensus in each country. Viraemic prevalence in this study ranged from 0.2% in Hong Kong to 2.4% in Taiwan, while the largest viraemic populations were in Nigeria (2 597 000 cases) and Taiwan (569 000 cases). Diagnosis, treatment and liver transplant rates varied widely across the countries included in this analysis, as did the availability of reliable data. Addressing data gaps will be critical for the development of future strategies to manage and minimize the disease burden of hepatitis C.

The present and future disease burden of hepatitis C virus infections with today's treatment paradigm: Volume 4

Factors influencing the morbidity and mortality associated with viremic hepatitis C virus (HCV) infection change over time and place, making it difficult to compare reported estimates. Models were developed for 17 countries (Bahrain, Bulgaria, Cameroon, Colombia, Croatia, Dominican Republic, Ethiopia, Ghana, Hong Kong, Jordan, Kazakhstan, Malaysia, Morocco, Nigeria, Qatar and Taiwan) to quantify and characterize the viremic population as well as forecast the changes in the infected population and the corresponding disease burden from 2015 to 2030. Model inputs were agreed upon through expert consensus, and a standardized methodology was followed to allow for comparison across countries. The viremic prevalence is expected to remain constant or decline in all but four countries (Ethiopia, Ghana, Jordan and Oman); however, HCV-related morbidity and mortality will increase in all countries except Qatar and Taiwan. In Qatar, the high-treatment rate will contribute to a reduction in total cases and HCV-related morbidity by 2030. In the remaining countries, however, the current treatment paradigm will be insufficient to achieve large reductions in HCV-related morbidity and mortality.

Strategies to manage hepatitis C virus infection disease burden-Volume 4

The hepatitis C virus (HCV) epidemic was forecasted through 2030 for 17 countries in Africa, Asia, Europe, Latin America and the Middle East, and interventions for achieving the Global Health Sector Strategy on viral hepatitis targets-"WHO Targets" (65% reduction in HCV-related deaths, 90% reduction in new infections and 90% of infections diagnosed by 2030) were considered. Scaling up treatment and diagnosis rates over time would be required to achieve these targets in all but one country, even with the introduction of high SVR therapies. The scenarios developed to achieve the WHO Targets in all countries studied assumed the implementation of national policies to prevent new infections and to diagnose current infections through screening.

A case report of metastasis of malignant mesothelioma to the retromolar trigone

Background

Malignant mesothelioma is a rare and aggressive tumor with a poor prognosis. Distant metastases are very rare, and the oral cavity metastases are exceedingly rare. Only a few cases with metastasis to oral gingiva are reported. To our knowledge, this is the first case report of pleural mesothelioma metastasized to the retromolar trigone.

Case presentation

A 59-year-old male was referred with a painless growth at retromolar trigone area. It had been present for 2 months and had increased in size during this period of time. Past medical history revealed a malignant mesothelioma. Intraoral examination showed a soft, haemorrhagic, ulcerated lesion at the right retromolar trigone area. There was no destruction of the bony architecture. An incisional biopsy was performed under local anaesthesia. Based on the histopathological and immunohistochemical findings, a final diagnosis of metastatic mesothelioma was made. The patient was informed about the possibility of multiple metastases within the body, but he succumbed after 45 days following deterioration of his medical condition.

Conclusions

Biopsy, history of the patient and clinical picture were provided to the clinicians to make an efficient differential diagnosis. Differential diagnosis must be performed with other oral cancers, because the management is totally different.

Volume and landmark analysis: comparison of MRI measurements obtained with an endorectal coil and with a phased-array coil

AIM

To compare prostate volumes and distances between anatomical landmarks on MRI images obtained with a phased-array coil (PAC) only and with a PAC and an endorectal coil (ERC).

MATERIALS AND METHODS

Informed consent was waived for this Health Insurance Portability and Accountability Act-compliant study. Fifty-nine men underwent PAC-MRI and ERC-MRI at 1.5 (n = 3) or 3 T (n = 56). On MRI images, two radiologists independently measured prostate volume and distances between the anterior rectal wall (ARW) and symphysis pubis at the level of the verumontanum; ARW and symphysis pubis at the level of the mid-symphysis pubis; and bladder neck and mid-symphysis pubis. Differences between measurements from PAC-MRI and ERC-MRI were assessed with the Wilcoxon RANK SUM test. Inter-reader agreement was assessed using the concordance correlation coefficient (CCC).

RESULTS

Differences in prostate volume between PAC-MRI and ERC-MRI [median: -0.75 mm(3) (p = 0.10) and median: -0.84 mm(3) (p = 0.06) for readers 1 and 2, respectively] were not significant. For readers 1 and 2, median differences between distances were as follows: -10.20 and -12.75 mm, respectively, ARW to symphysis pubis at the level of the verumontanum; -6.60 and -6.08 mm, respectively, ARW to symphysis pubis at the level of the mid-symphysis pubis; -3 and -3 mm respectively, bladder neck to mid-symphysis pubis. All differences in distance were significant for both readers (p ≤ 0.0005). Distances were larger on PAC-MRI (p ≤ 0.0005). Inter-reader agreement regarding prostate volume was almost perfect on PAC-MRI (CCC: 0.99; 95% CI: 0.98-1.00) and ERC-MRI (CCC: 0.99; 95% CI: 0.99-1.00); inter-reader agreement for distance measurements varied (CCCs: 0.54-0.86).

CONCLUSION

Measurements of distances between anatomical landmarks differed significantly between ERC-MRI and PAC-MRI, although prostate volume measurements did not.

Role of endorectal prostate MRI in patients with initial suspicion of prostate cancer

PURPOSE

To evaluate the role of conventional endorectal prostate MRI in patients with initial suspicion of prostate cancer.

MATERIALS AND METHODS

Ethics board approval was received for this retrospective study of 87 men who underwent 1.5-Tesla conventional prostate MRI with a combination of endorectal and body phased-array coils for suspected prostate cancer before their first systematic 12-core TRUS-guided biopsy. Three radiologists independently analyzed the images, dividing the prostate into 12 regions corresponding to the biopsy scheme and scoring each region for the presence of prostate cancer on a 5-point scale. Results were analyzed by prostate region. ROC analysis was done and descriptive statistics were calculated. The negative predictive value, specificity, sensitivity and positive predictive value were calculated using dichotomized scores (benign tissue = scores of 1 and 2; malignant tissues = scores of 3, 4, and 5).

RESULTS

Biopsy revealed cancer in 47/87 patients (26 low-grade [Gleason score 6]; 21 high-grade [Gleason score ≥ 3 + 4]), and 184/1044 cores (77 low-grade and 107 high-grade) with a median of 3 positive cores per cancer patient (range 1 – 12). The areas under ROC curves were 0.65 – 0.67 for cancer detection by region overall and 0.75 – 0.76 for the detection of high-grade cancer by region. Statistic figures for the detection of all cancers/high-grade cancers by region were as follows: negative predictive value, 87.4 – 88.2 %/92.6 – 93.1 %; specificity, 72.3 – 79.4 %/71.5 – 79.8 %; sensitivity, 49.5 – 54.8 %/62.6 – 69.2 %; and positive predictive value, 29.3 – 34.0 %/29.4 – 34.7 %.

CONCLUSION

In patients with suspected prostate cancer, negative MRI findings indicate the absence of high-grade prostate cancer on subsequent TRUS-guided 12-core biopsy with high probability. However, agreement between conventional 1.5-T endorectal prostate MRI and systematic 12-core TRUS-guided biopsy for the detection of prostate cancer appears to be moderate.

Role of endorectal prostate MRI in patients with initial suspicion of prostate cancer

PURPOSE

To evaluate the role of conventional endorectal prostate MRI in patients with initial suspicion of prostate cancer.

MATERIALS AND METHODS

Ethics board approval was received for this retrospective study of 87 men who underwent 1.5-Tesla conventional prostate MRI with a combination of endorectal and body phased-array coils for suspected prostate cancer before their first systematic 12-core TRUS-guided biopsy. Three radiologists independently analyzed the images, dividing the prostate into 12 regions corresponding to the biopsy scheme and scoring each region for the presence of prostate cancer on a 5-point scale. Results were analyzed by prostate region. ROC analysis was done and descriptive statistics were calculated. The negative predictive value, specificity, sensitivity and positive predictive value were calculated using dichotomized scores (benign tissue = scores of 1 and 2; malignant tissues = scores of 3, 4, and 5).

RESULTS

Biopsy revealed cancer in 47/87 patients (26 low-grade [Gleason score 6]; 21 high-grade [Gleason score ≥ 3 + 4]), and 184/1044 cores (77 low-grade and 107 high-grade) with a median of 3 positive cores per cancer patient (range 1 - 12). The areas under ROC curves were 0.65 - 0.67 for cancer detection by region overall and 0.75 - 0.76 for the detection of high-grade cancer by region. Statistic figures for the detection of all cancers/high-grade cancers by region were as follows: negative predictive value, 87.4 - 88.2 %/92.6 - 93.1 %; specificity, 72.3 - 79.4 %/71.5 - 79.8 %; sensitivity, 49.5 - 54.8 %/62.6 - 69.2 %; and positive predictive value, 29.3 - 34.0 %/29.4 - 34.7 %.

CONCLUSION

In patients with suspected prostate cancer, negative MRI findings indicate the absence of high-grade prostate cancer on subsequent TRUS-guided 12-core biopsy with high probability. However, agreement between conventional 1.5-T endorectal prostate MRI and systematic 12-core TRUS-guided biopsy for the detection of prostate cancer appears to be moderate.

Serum heavy metal and antioxidant element levels of children with recurrent wheezing

STUDY OBJECTIVES

The aim of the study is to investigate the levels of toxic heavy metals related with environmental pollution and trace elements involved in antioxidant system in children suffering from recurrent wheezing.

STUDY DESIGN

One hundred children with recurrent wheezing (at least three recurrences) between the ages from 1 to 6 years took part in the study, and also 116 age- and sex- matched healthy children were involved in the study as a control group. Venous blood samples were collected and serum mercury, lead, aluminium, zinc, selenium, and copper levels were studied using ICP-MS.

RESULTS

Serum lead (0.76±0.15 vs. 0.27±0.01, p:0.001) and mercury levels (1.31±0.15 vs 0.71±0.05, p<0.001) were higher in wheezy group than those acquired from the control group. Serum zinc (69.4±1.65 vs. 78.9±2.78, p:0.005) and selenium (115.6±1.87 vs. 125.4±2.94, p:0.008) levels were lower in wheezy group than those acquired from the control group. Serum zinc levels were found to be correlated with number of ARTIs (r(p):-0.332, p:0.001) and the number of wheezy attacks (r(p):-0.776, p<0.001) during the previous year in the wheezy group.

CONCLUSION

Elevated levels of serum lead and mercury and low levels of zinc and selenium may suggest some disturbances in the antioxidant system in children with recurrent wheezing. This means that children with recurrent wheezing are much more susceptible to environmental pollutants and respiratory tract infections than healthy children and this heavy metal-antioxidant relationship may play a role as a contributing factor in the pathogenesis of recurrent wheezing in children.

Ghrelin immunohistochemistry of gastric adenocarcinoma and mucoepidermoid carcinoma of salivary gland

Ghrelin (G-HH) synthesized in several tissues including salivary and stomach glands stimulates appetite in humans by modulating neuropeptide Y neurons in the hypothalamic arcuate nucleus. Loss of appetite is one of the most important symptoms of stomach cancer. We conducted a study using immunohistochemistry to determine whether salivary glands and stomach cancer tissues produce ghrelin. We determined that negative ghrelin immunohistochemistry discriminates tumors from normal tissues and may therefore further our understanding of the clinically important problem of reduced food intake and anorexia in cancer patients. Radioimmunoassay analyses confirmed that cancer cells do not produce a G-HH peptide, whereas normal cells yield this peptide.

The role of positron emission tomography/computed tomography in the diagnosis of pleural diseases

BACKGROUND

The aim of the study was to assess the role of F-18 fluoro-2-D-deoxyglucose positron emission tomography ( (18)FDG-PET)/computed tomography (CT) in patients with undiagnosed pleural diseases and to compare the findings with those of invasive diagnostic procedures.

METHODS

The study included 83 patients with pleural lesions (63 with pleural effusion; 20 with pleural thickening) on CT scan performed between November 2005 and December 2007. The study group consisted of 63 males and 20 females; their median age was 47 years. PET-CT scan was performed for all patients before surgery. A maximum standard uptake value greater than 3.0 was accepted as positive for malignancy. For histopathological diagnosis, video-assisted thoracoscopic surgery was performed in 76 patients and a mini-thoracotomy was performed for the remaining 7 patients.

RESULTS

Postoperative histopathological examination revealed malignancy in 44 cases, 25 of which were malignant mesothelioma; the remaining 39 cases were benign. There were no false negative results, but two false positive results (tuberculosis). PET-CT scanning had 100 % sensitivity, 94.8 % specificity and 97.5 % accuracy.

CONCLUSION

Our study suggests that PET-CT may be an effective tool for the differentiation of benign and malignant pleural diseases. We believe that PET/CT may prevent redundant surgical procedures in young patients who are SUVmax negative.

Effects of Cholerella sp. microalgae extract on colonic anastomosis in rats with protein-energy malnutrition

OBJECTIVE

Algae, which are used as supplementary nutrients in various countries, are products rich in protein, vitamins and minerals. The aim of this study was to investigate the effects of algae extracts on the healing of colonic anastomosis in malnourished rats.

METHOD

Seventy-two rats were randomized to three groups. Group 1 was fed with standard diet for 15 days, before and after the colonic anastomosis. Groups 2 and 3 were fed with a malnutrition diet for 15 days prior to colonic anastomosis and then with the basic diet for 15 days there after. Group 3 also received an extract of algae derived from Cholerella sp. via oral gavage postoperatively, in addition to the basic diet. Rats were killed on the 3rd, 7th and 15th postoperative day. Blood samples were collected to evaluate prealbumin, transferring and albumin levels. Anastomotic bursting pressures (BPs), histopathology and tissue hydroxyproline levels were evaluated after killing.

RESULTS

In group 3, the prealbumin level on the 3rd postoperative day and transferrin and albumin levels on the 7th and 15th postoperative days were significantly increased compared with the other groups (P < 0.05). Tissue hydroxyproline levels and anastomotic BPs of group 3 were significantly higher than in group 2 on the 3rd, 7th and 15th postoperative days (P < 0.05). Histopathological examination of the anastomosis revealed significantly better healing patterns for group 3 than for groups 1 and 2 (P < 0.05).

CONCLUSION

Extract derived from Cholerella sp. microalgae has favourable effects on healing of experimental colon anastomoses.

Prostate cancer imaging

As prostate cancer is a biologically heterogeneous disease for which a variety of treatment options are available, the major objective of prostate cancer imaging is to achieve more precise disease characterization. Magnetic resonance imaging (MRI) may enhance the staging of prostate cancer compared with clinical evaluation, transrectal ultrasound, or computed tomography (CT), and allows concurrent evaluation of prostatic, periprostatic, and pelvic anatomy. In clinical practice, the fusion of MRI or dynamic contrast-enhanced MRI (DCE-MRI) with MR spectroscopic imaging (MRSI) is improving the evaluation of cancer location, size, and extent, while providing an indication of tumor aggressiveness. Pretreatment knowledge of these prognostic variables is essential for achieving minimally invasive, patient-specific therapy.

Painless burn injury caused by post-traumatic syringomyelia

BACKGROUND

Syringomyelia, which is generally related to congenital malformations and tumors, may lead to paresthesia and dysfunctions in thermo-algesic perception. Post-traumatic syringomyelia (PTS) is a rare type of this disease characterised by the development of a cystic formation containing cerebrospinal fluid (CSF), which develops inside the spinal cord after spinal trauma.

AIM

The description of a case diagnosed as painless burn injury caused by PTS.

METHOD

One case report.

CONCLUSION

Although there are a number of reports regarding the formation of neuropathic ulcers related to syringomyelia, painless burn injury descriptions are very rare. Despite available limited data related to this subject, it is important to warn patients about traumas-especially burns-after a diagnosis of PTS.

Metronidazole 0.75% gel vs. ketoconazole 2% cream in the treatment of facial seborrheic dermatitis: a randomized, double-blind study

BACKGROUND

Recently, two placebo-controlled studies have shown that topical metronidazole was effective in the treatment of seborrheic dermatitis.

OBJECTIVE

To compare the efficacy and safety of metronidazole 0.75% gel with that of ketoconazole 2% cream in the treatment of facial seborrheic dermatitis.

METHODS

A total of 60 consecutive patients with facial seborrheic dermatitis were included. Patients were randomized into two groups. One group used ketoconazole 2% cream with metronidazole gel as vehicle; the other group used metronidazole 0.75% gel with ketoconazole cream as vehicle for a 4-week treatment period. Main outcome measures were change in clinical severity scores, patients' and investigator's global evaluation of improvement and frequency of side-effects.

RESULTS

All the assessments were made by an investigator who was unaware of which group the patients were allocated to. Mean percentage decrease in clinical severity scores from baseline to last available visit was 63.4% (95% CI 57.7-69) and 54.4% (95% CI 47.9-61) in the ketoconazole- and metronidazole-treated patients, respectively (P = 0.31). Eighty-two per cent of patients in the ketoconazole group vs. 79% of patients in the metronidazole group rated their global improvement as significant or moderate (P > 0.05). No statistically significant difference in the frequency of side-effects was detected between the two groups. The results of this study need to be confirmed in further studies involving large numbers of patients.

CONCLUSION

Our data demonstrated that metronidazole 0.75% gel had a comparable efficacy and safety profile with that of ketoconazole 2% cream in the treatment of facial seborrheic dermatitis.

Evaluation of bone turnover in postmenopausal patients with type 2 diabetes mellitus using biochemical markers and bone mineral density measurements

Although osteoporosis is reported as a potential complication of type 1 diabetes mellitus (DM), the effects of type 2 DM on bone mass are conflicting. Most of the studies conducted in recent years reveal that bone mineral density (BMD) values of type 2 DM patients are not decreased and even increased when compared with healthy control groups. In this study we evaluated bone turnover in 57 postmenopausal type 2 DM patients utilizing biochemical markers for bone formation and resorption, and BMD measurements. We found that BMD values in diabetic patients (0.91 +/- 0.11 g/cm(2) for lumbar region, 0.89 +/- 0.14 g/cm(2) for hip region) were higher than healthy postmenopausal control group (0.81 +/- 0.12 g/cm(2) for lumbar region, 0.76 +/- 0.10 g/cm(2) for hip region). Serum alkaline phosphatase values were similar to the control group, whereas serum osteocalcin and N-telopeptide/creatinine (NTx/Cr) values were significantly lower than the control group (osteocalcin: 8.82 +/- 4.03 ng/ml, NTx/Cr: 122.70 +/- 81.76 nMBCE/mMCr) in diabetic patients (osteocalcin: 4.44 +/- 3.53 ng/ml, NTx/Cr: 42.24 +/- 29.97 nMBCE/mMCr). Also a significant correlation was observed between body mass index and BMD values. Our findings suggested that the bone turnover rate is remarkably lower in type 2 DM patients compared to healthy postmenopausal patients.

Hepatic alveolar echinococcosis. A case report

Alveolar echinococcosis is a rare parasitic disease caused by Echinococcus multilocularis and most commonly involves the liver. Early diagnosis and precise evaluation of the localisation and the extent of the lesions are essential for treatment. In this report, we present US and CT findings in a patient with hepatic alveolar echinococcosis.

Erectile dysfunction in premature ejaculation

Between October 1993 and December 1995, 45 patients with premature ejaculation were included in this study. The patients were divided into two groups etiologically, as having primary or secondary ejaculation. After a complete laboratory evaluation all patients underwent papaverine tests color Doppler ultrasonography pharmacocavernosometry-cavernosography and consequently organic etiology were investigated. Venous leakage was found in 5 (22,7%), arterial or mix insufficiency in 2 (9%) of the patients with primary premature ejaculation. In secondary premature ejaculation group, venous leakage was encountered in 9 patients (39,1%), arterial insufficiency in 2 patients (8,6%). In conclusion, investigation of organic etiology for the patients with premature ejaculation, particularly with secondary premature ejaculation, seems to be beneficial for correct diagnosis.

A case of growing teratoma syndrome

Residual masses are a common finding after chemotherapy for metastases from nonseminomatous germ cell tumours of the testes. The prognosis of these patients with resected teratoma following successful cisplatin-based combination chemotherapy generally has been assumed to be good. Herein we reported an unusual teratoma case named "growing teratoma syndrome' by Logothetis et al. This patient was treated with multiple operations.

Evoked-potential monitoring during dorsal root entry zone surgery. An experimental animal model

Spinal cord evoked potentials (SCEP) in response to epispinal stimulation were measured in an experimental animal model designed to define further the value of electrophysiological monitoring during dorsal root entry zone (DREZ) surgery. Thirteen cats underwent microsurgical stereotactic thermal radiofrequency lesions of the DREZ. The postmortem histological examination of the location and extent of the lesions were compared with the intraoperative electrophysiological and postoperative neurological effects. Despite the use of the stereotactic microsurgical technique, the sizes and the configurations of the DREZ lesions varied greatly. Changes in ascending and descending SCEP correlated highly with the extent of the histologically defined injury to the dorsal and lateral columns. SCEP monitoring during experimental DREZ surgery provided a sensitive indication of lesion invasion into the dorsal or lateral columns. The high degree of correlation between changes in descending SCEP and extension of the surgical lesion into the lateral column indicates that the SCEP technique is more sensitive than somatosensory cortical evoked potentials in the intraoperative electrophysiological assessment of corticospinal tract function, and it may prove to be a useful surgical adjunct during DREZ surgery in humans.

Anatomical study of the cavernous sinus emphasizing operative approaches and related vascular and neural reconstruction

The efficacy of three operative approaches to the cavernous sinus (CS) and the possibilities of vascular and cranial nerve reconstruction in and around the CS were studied in 50 cadaver specimens (25 heads). The lateral operative approach was through the lateral wall, between Cranial Nerves V1 and IV, or between Cranial Nerves V1 and V2. The superior approach was through the superior wall of the CS after removing the anterior clinoid process and unroofing the optic canal. The inferior approach followed the petrous internal carotid artery (ICA) into the CS after an extradural subtemporal exposure or after a combined subtemporal and infratemporal fossa exposure. The different exposures of the spaces of the CS and of the intracavernous structures provided by the superior and the lateral approaches were complementary. The exposure provided by the inferior approach was minimal; however, the junction of the petrous and cavernous ICA was best exposed by this route. The combined subtemporal and infratemporal fossa approach exposed the petrous ICA (for proximal control or for reconstruction) with the greatest ease and with the least temporal lobe retraction. The combination of the superior and lateral approaches and the complete mobilization of the intracavernous ICA facilitated its repair after experimental lacerations. Lacerations of either the inferior and the inferomedial aspects of any portion of the cavernous ICA or of the anterior surface of the posterior vertical segment of the artery were the most difficult to repair. End-to-end anastomosis was more difficult with the posterior third of the artery than with the anterior two-thirds. A vein graft with an average length of 3.5 cm could be sutured from the petrous to the supraclinoid ICA to bypass the cavernous ICA, with an average occlusion time of 45 minutes. End-to-end technique was judged better for the proximal anastomosis, but end (graft)-to-side anastomosis was easier to perform at the distal end because of the location of the ophthalmic artery. Resuture of Cranial Nerves III and VI could not be performed in fresh cadavers if the gap exceeded 0.3 cm. In 3 specimens, the exposure of Cranial Nerve VI in the posterior fossa through the petrous apex and in the orbital apex was followed by graft placement (bypassing the CS). The complex anatomy of the cranial nerves at the apex of the CS was also defined in 10 specimens. Surgeons who perform operations in and around the CS for neoplastic and vascular lesions will find these studies useful.

Quantification of three-dimensional structures

A mathematical model, based on additive subcomponents of grouping, subitizing and adding, was derived to account for quantification latencies of three-dimensional block arrangements. Subitizing is the process that people use to directly quantify a small number of objects without counting. It was found that most people consistently subitized up to four blocks. With more than four blocks, people resorted to grouping and adding, and the model was able to account for these data. The structural variables of compactness, symmetry, linearity, and planarity were shown to have small effects on quantification latencies relative to the large effect of number of blocks. Of these structural variables, compactness had the largest effect, and in terms of the model, it is suggested that visual structure had its effect on the perceptual grouping subcomponent.

Quantification of three-dimensional structures

A mathematical model, based on additive subcomponents of grouping, subitizing and adding, was derived to account for quantification latencies of three-dimensional block arrangements. Subitizing is the process that people use to directly quantify a small number of objects without counting. It was found that most people consistently subitized up to four blocks. With more than four blocks, people resorted to grouping and adding, and the model was able to account for these data. The structural variables of compactness, symmetry, linearity, and planarity were shown to have small effects on quantification latencies relative to the large effect of number of blocks. Of these structural variables, compactness had the largest effect, and in terms of the model, it is suggested that visual structure had its effect on the perceptual grouping subcomponent.