Effect of shunt surgery on spleen size, portal pressure and oesophageal varices in patients with non-cirrhotic portal hypertension

Shunt surgery is considered to be the treatment of choice in patients with non-cirrhotic portal hypertension. There is little data on the effect of side-to-side lieno-renal (SSLR) shunt on oesophageal variceal size, splenic size and splenic pulp pressure (SPP) in patients with non-cirrhotic portal hypertension. We evaluated pre- and postoperatively endoscopic grading of varices, splenic size and SPP for predicting shunt patency in 86 patients with non-cirrhotic portal hypertension: 56 with extrahepatic portal venous obstruction (EHPVO) and 30 with non-cirrhotic portal fibrosis (NCPF). The EHPVO patients with patent shunts (n= 47) showed significant reduction in SPP (pre-operative 43.56±7.9 vs postoperative 29.96±7.7 cm of saline), splenic size (6.5±2.8 vs 4.00±2.6 cm below costal margin) and varices grades (2.96±0.5 vs 0.92±0.8). Patients with blocked shunt (n= 9) did not show significant reduction in SPP and varices grades. However, there was reduction in spleen size (8.6±3.0 vs 6.3±4.3). In the NCPF group, 28 had patent shunts and showed significant reduction in SPP (46.3±13.5 vs 33.8±7.6 cm of saline), splenic size (9.1±3.3 vs 6.8±4.6 cm below costal margin) and varices grades (2.8±0.7 vs 1.05±0.96). As only two patients with NCPF had blocked shunts, no statistical comparison between patients with patent and patients with blocked shunts could be done. In conclusion, following SSLR, there is a significant reduction in SPP and varices grades in patients with patent shunts. Endoscopic grading of varices can be used to predict shunt patency. However, spleen size is not a good criteria for predicting shunt patency.     

Increases in oxygen consumption without cerebral blood volume change during visual stimulation under hypotension condition.

The magnitude of the blood oxygenation level-dependent (BOLD) signal depends on cerebral blood flow (CBF), cerebral blood volume (CBV) and cerebral metabolic rate of oxygen (CMRO2). Thus, it is difficult to separate CMRO2 changes from CBF and CBV changes. To detect the BOLD signal changes induced only by CMRO2 responses without significant evoked CBF and CBV changes, BOLD and CBV functional magnetic resonance imaging (fMRI) responses to visual stimulation were measured under normal and hypotension conditions in isoflurane-anesthetized cats at 4.7 T. When the mean arterial blood pressure (MABP) decreased from 89+/-10 to 50+/-1 mm Hg (mean+/-standard deviation, n=5) by infusion of vasodilator sodium nitroprusside, baseline CBV in the visual cortex increased by 28.4%+/-8.3%. The neural activity-evoked CBV increase in the visual cortex was 10.8%+/-3.9% at normal MABP, but was negligible at hypotension. Positive BOLD changes of +1.8%+/-0.5% (gradient echo time=25 ms) at normal MABP condition became prolonged negative changes of -1.2%+/-0.3% at hypotension. The negative BOLD response at hypotension starts approximately 1 sec earlier than positive BOLD response, but similar to CBV change at normal MABP condition. Our finding shows that the negative BOLD signals in an absence of CBV changes are indicative of an increase in CMRO2. The vasodilator-induced hypotension model simplifies the physiological source of the BOLD fMRI signals, providing an insight into spatial and temporal CMRO2 changes.     

Comparison of Phaconit Rollable IOL with Acrylic Foldable IOL

Background

Phaconit or ultra micro incision phacoemulsification cataract surgery involves phacoemulsification through a 0.9 millimetre sleeveless phaco tip and irrigating chopper followed by implantation of a rollable intraocular lens. The procedure leads to negligible astigmatism and faster visual recovery as compared to phacoemulsification with a foldable intraocular lens.

Methods

This prospective study analysed 80 cases of sub millimetre phaconit surgery with implantation of rollable intraocular lenses(IOL) in 40 cases and acrylic foldable IOL in the remaining 40 cases. Evaluation of efficacy and adaptability of procedure, equipment settings, operative constraints, postoperative complications, keratometric and topographic evaluation of induced astigmatism with visual outcome and patient''s rehabilitation were studied.

Results

The intraoperative complications were surge/ chamber collapse in 16 (20%), iris chaffing in one and corneal burns in two cases. All cases had an induced astigmatism of less than or equal to ± 0.25 D in four to six weeks after rollable IOL and ± 0.5 D to ± 0.75 D after acrylic IOL implantation. All patients had best-corrected visual acuity of 6/6 by third post operative day.

Conclusion

Phaconit with rollable IOL is a perfect blend of surgical skill, application of technology and ultra thin IOL.Key Words: Phaconit, Ultra micro phaco, Submillimetre incision, Rollable IOL implantation     

The relationship between hypertension and anxiety or depression in Hong Kong Chinese

BACKGROUND:

Psychosocial stress can be the cause or the consequence of hypertension.

OBJECTIVE:

To study the association between hypertension and anxiety or depression in adults from Hong Kong, China.

SUBJECTS AND METHODS:

Patients with diagnosed hypertension (n=197) were recruited to complete the Hospital Anxiety and Depression Scale (HADS) questionnaire. The control group comprised 182 normotensive subjects recruited using random telephone numbers.

RESULTS:

The score in the anxiety subscale (HADS-A) of the HADS correlated with age (r= −0.23, P<0.001) and sex (r=0.11, P=0.042), and was found to be higher in women. The score in the depression subscale (HADS-D) correlated with age (r=0.17, P=0.003) and hypertension (r=0.12, P=0.039), but not with sex (r=0.02, P=0.68). When the control subjects were matched for sex and age with the subjects with hypertension, the mean HADS-A score was 5.51±0.41 in 113 hypertensive subjects and 4.38±0.39 in 113 normotensive subjects (P=0.047). The mean HADS-D score was 5.56±0.39 in the hypertensive and 4.76±0.32 in the normotensive subjects (P=0.11). Multiple regression analysis using data from both groups indicated that the HADS-A score was related to the HADS-D score (β=0.49, P<0.001), age (β= −0.25, P<0.001) and sex (β=0.12, P=0.01) (R²=0.28), whereas the HADS-D score was related to the HADS-A score (β=0.48, P<0.001), age (β=0.30, P<0.001), positive smoking status (β=0.13, P=0.004) and lack of exercise habit (β=0.12, P=0.008) (R²=0.31). Hypertension was related to waist circumference, history of parental hypertension and age (R²=0.38, P<0.001). Anxiety and depression scores were rejected as independent variables.

CONCLUSIONS:

Hypertension was associated with anxiety but not depression; however, age, history of parental hypertension and central obesity appeared to have a stronger association with hypertension in adults from Hong Kong.     

Molecular characterization of commercial porcine factor VIII concentrate

Commercial porcine factor VIII concentrate (Hyate:C) is effective in treatment of patients with hemophilia A who have circulating antibodies to factor VIII. The molecular forms of factor VIII in the concentrate were identified and evaluated in light of the known properties of porcine and human factor VIII. The factor VIII in the concentrate was isolated by tandem chromatography on gelatin-Sepharose and monoclonal anti-factor VIII-Sepharose. The factor VIII was 1% of the protein mass of the concentrate when calculated by either quantity of protein recovered or by radioimmunoassay. Both functional assay and Western blotting of the crude concentrate indicated that maximum coagulant function was achieved by proteolytic activation of procofactor forms of factor VIII. The factor VIII can be fractionated by cation-exchange high-performance liquid chromatography (HPLC) into two or three species of heterodimers depending on the lot. The specific activity of the purified porcine factor VIII was 550 U/mg using pooled porcine plasma at 1 U/mL as a standard. From this value, a factor VIII concentration in normal pig plasma of 2 micrograms/mL was calculated. This agreed well with a value of 3 micrograms/mL obtained by radioimmunoassay (RIA) of factor VIII in porcine plasma. In contrast, reported values for human factor VIII average 5800 U/mg, resulting in a calculated concentration in plasma of 0.2 microgram/mL. The finding that porcine plasma contains a significantly higher circulating mass of factor VIII than human plasma appears to explain previous difficulties in comparing porcine and human factor VIII in standard assays.