Intestinal Calcium Absorption Decreases Dramatically After Gastric Bypass Surgery Despite Optimization of Vitamin D Status

Roux‐en‐Y gastric bypass (RYGB) surgery has negative effects on bone, mediated in part by effects on nutrient absorption. Not only can RYGB result in vitamin D malabsorption, but the bypassed duodenum and proximal jejunum are also the predominant sites of active, transcellular, 1,25(OH)₂D‐mediated calcium (Ca) uptake. However, Ca absorption occurs throughout the intestine, and those who undergo RYGB might maintain sufficient Ca absorption, particularly if vitamin D status and Ca intake are robust. We determined the effects of RYGB on intestinal fractional Ca absorption (FCA) while maintaining ample 25OHD levels (goal ≥30 ng/mL) and Ca intake (1200 mg daily) in a prospective cohort of 33 obese adults (BMI 44.7 ± 7.4 kg/m²). FCA was measured preoperatively and 6 months postoperatively with a dual stable isotope method. Other measures included calciotropic hormones, bone turnover markers, and BMD by DXA and QCT. Mean 6‐month weight loss was 32.5 ± 8.4 kg (25.8% ± 5.2% of preoperative weight). FCA decreased from 32.7% ± 14.0% preoperatively to 6.9% ± 3.8% postoperatively (p < 0.0001), despite median (interquartile range) 25OHD levels of 41.0 (33.1 to 48.5) and 36.5 (28.8 to 40.4) ng/mL, respectively. Consistent with the FCA decline, 24‐hour urinary Ca decreased, PTH increased, and 1,25(OH)₂D increased (p ≤ 0.02). Bone turnover markers increased markedly, areal BMD decreased at the proximal femur, and volumetric BMD decreased at the spine (p < 0.001). Those with lower postoperative FCA had greater increases in serum CTx (ρ = ?0.43, p = 0.01). Declines in FCA and BMD were not correlated over the 6 months. In conclusion, FCA decreased dramatically after RYGB, even with most 25OHD levels ≥30 ng/mL and with recommended Ca intake. RYGB patients may need high Ca intake to prevent perturbations in Ca homeostasis, although the approach to Ca supplementation needs further study. Decline in FCA could contribute to the decline in BMD after RYGB, and strategies to avoid long‐term skeletal consequences should be investigated. © 2015 American Society for Bone and Mineral Research.     

Magnetic resonance angiography image guidance for the microsurgical clipping of intracranial aneurysms: a report of two cases

Abstract

To describe the integration of magnetic resonance angiography (MRA) in neuronavigation procedures for microsurgery of intracranial aneurysms. MRA was combined with standard magnetic resonance image (MRI) acquisition in the image-guided planning for the microsurgical clipping of a saccular aneurysm in two patients (one 3-mm large middle cerebral artery and one 8-mm large pericallosal artery aneurysm, diagnosed by catheter angiography in both patients) using two different neurosurgical navigation systems. Conventional 3-D T1-weighted MRI with gadolinium and MRA pulse sequences were acquired in frameless stereotactic conditions the day before surgery and thereafter registered, allowing the definition a minimally invasive straight trajectory to the aneurysm neck. MRA-guided neurosurgery allowed a direct approach to the aneurysms at their proper location, reducing the invasiveness of the approach by tailoring the bone opening and reducing the duration and extension of brain retraction. The technique also avoided unnecessary dissection and exposure of the main trunks and collateral vessels. The aneurysms were successfully eradicated without complication. Integration of MRA in the planning and neuronavigation procedure for intracranial aneurysms may minimize the morbidity related to the surgical approach. This technique may be applicable more routinely using standard neuronavigation equipment.     

Nonremission and Recurrent Tumor-Induced Osteomalacia: A Retrospective Study

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome. It is curable by excision of the causative tumor. However, a few cases may persist or relapse after tumor resection. We aimed to investigate the rate of these events and related factors. We retrospectively studied TIO patients treated with surgery in a tertiary hospital. TIO was established based on a pathologic examination or the reversion of hypophosphatemia. Refractory TIO patients consisted of those with nonremission or recurrent hypophosphatemia after surgery. A total of 230 patients were confirmed as having TIO. After primary surgery, 26 (11.3%) cases persisted, and 16 (7.0%) cases recurred. The overall refractory rate was 18.3%. The median time of recurrence was 33 months. Compared with patients in the recovery group, patients in the refractory group were more likely to be female (59.5% versus 41.0%, p = .029) and have a lower serum phosphate level (0.44 ± 0.13 versus 0.50 ± 0.11 mmol/L, p = .002). The refractory rate was lowest in head/neck tumors (7.5%) and highest in spine tumors (77.8%). Regarding the tissue involved of tumor location, the refractory rate was higher in tumors involving bone than tumors involving soft tissue (32.7% versus 7.0%, p < .001). The outcomes of malignant tumors were worse than those of benign tumors (p < .001): nonremission rate, 21.4% versus 9.7%; recurrence rate, 28.6% versus 6.5%. In the multivariate regression analysis, female sex, spine tumors, bone tissue-involved tumors, malignancy, and low preoperation serum phosphorus levels were identified as risk factors for refractory outcomes. High preoperative fibroblast growth factor 23 (FGF23) levels were also associated with refractory after adjusting for involving tissue and tumor malignancy. In summary, we are the first to report the rate and clinical characteristics of refractory TIO in a large cohort. For patients with multiple risk factors, especially spine tumors, clinical practitioners should be aware of a poor surgical prognosis. © 2019 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.     

Gastric Bypass But Not Sleeve Gastrectomy Increases Risk of Major Osteoporotic Fracture: French Population-Based Cohort Study

The objective of this work was to investigate the risk of major osteoporotic fracture (MOF; hip, proximal humerus, wrist and distal forearm, and clinical spine) in bariatric surgery patients versus matched controls. Bariatric surgery is associated with an increase in fracture risk. However, it remains unclear whether the same degree of fracture risk is associated with sleeve gastrectomy, which has recently surpassed gastric bypass. Records from the French National Inpatient database were used from 2008 to 2018. Bariatric surgery patients, aged 40 to 65 years, with BMI ≥40 kg/m², hospitalized between January 1, 2010 and December 31, 2014, were matched to one control (1:1) by age, sex, Charlson comorbidity index, year of inclusion, and class of obesity (40 to 49.9 kg/m² versus ≥50 kg/m²). We performed a Cox regression analysis to assess the association between the risk of any MOF and, respectively, (i) bariatric surgery (yes/no) and (ii) type of surgical procedure (gastric bypass, gastric banding, vertical banded gastroplasty, and sleeve gastrectomy) versus no surgery. A total of 81,984 patients were included in the study (40,992 in the bariatric surgery group, and 40,992 matched controls). There were 585 MOFs in the surgical group (2.30 cases per 1000 patient-year [PY]) and 416 MOFs in the matched controls (1.93 cases per 1000 PY). The risk of MOF was significantly higher in the surgical group (hazard ratio [HR] 1.22; 95% CI, 1.08–1.39). We observed an increase in risk of MOF for gastric bypass only (HR 1.70; 95% CI, 1.46–1.98) compared with the matched controls. In patients aged 40 to 65 years, gastric bypass but not sleeve gastrectomy or the other procedures increased risk of major osteoporotic fractures. © 2020 American Society for Bone and Mineral Research.     

Effect of Bariatric Surgery on Obstructive Sleep Apnea and Hypopnea Syndrome, Electrocardiogram, and Pulmonary Arterial Pressure

Background: We evaluated the impact of surgically-induced weight loss on Obstructive Sleep Apnea/Hypopnea Syndrome (OSAHS), electrocardiographic changes, pulmonary arterial pressure and daytime sleepiness in morbidly obese patients. Methods: 16 women and 13 men (n=29) underwent bariatric surgery in a 3-year period. The following tests were performed before and 1 year after surgery: nocturnal polysomnography, daytime Multiple Sleep Latency Test (MSLT), and echocardiogram. Results: Mean age was 37.9±11 years (range 20-56). Preoperative body mass index was 56.5±12.3 kg/m² and it was 39.2±8.5 kg/m² at 13.7±6.6 months follow-up. Performed surgical procedures included: vertical banded gastroplasty in 6, Roux-en-Y gastric bypass in 12, and Distal Roux-en-Y gastric bypass in 11. Weight loss induced by surgery eliminated OSAHS in 46% of obese patients with an important improvement in oxygen saturation. Neck, thorax, waist and hip circumferences decreased significantly after surgical intervention but only neck circumference correlated significantly with the apnea/hypopnea index (Spearman rho=0.63, P <0.0001). Electrocardiographic abnormalities were present in 9 patients (31%) before surgery (sinus arrhythmia, ventricular arrhythmias, and sinus arrest). The number of electrocardiographic abnormalities decreased after surgery but new abnormalities appeared in some patients. Systolic pulmonary arterial pressure significantly decreased in the group of patients in whom OSAHS disappeared after surgery. Daytime sleepiness persisted after surgery in most patients. Conclusion: Bariatric surgery effectively reduces respiratory disturbances during sleep and improves pulmonary hypertension. Electro cardiographic abnormalities change after surgery. Daytime sleepiness appeared not to be related to respiratory disturbances during sleep.     

胸腹主动脉夹层动脉瘤(Stanford B型)的腔内血管外科治疗

目的 探讨Stanford B型胸腹主动脉夹层动脉瘤腔内治疗的方法。方法 对l2例StanfordB型胸腹主动脉夹层动脉瘤患者的临床资料进行回顾性研究。结果 l2例患者全为男性，年龄40～68岁，平均52．1岁。其中10例患者进行了腔内血管外科治疗，均取得了技术上的成功，术后内漏1例，3d后漏血停止。其余病例术后即时造影示瘘口已被完整覆盖，假腔无血漏入，内脏动脉等恢复真腔供血。2例未行腔内治疗的患者，l例因并发呼衰死亡，l例死于夹层动脉瘤破裂。结论对Stanford B型胸腹主动脉夹层动脉瘤的治疗，如适应证掌握合适，腔内治疗与传统的开胸手术相比，具有操作简单，损伤小，安全度大，并发症少等优点，且可大大缩短患者的住院时间。保守治疗难以控制病情的发展，易导致死亡等严重后果。     

Virtual Gastroduodenoscopy: A New Look at the Bypassed Stomach and Duodenum After Laparoscopic Roux-en-Y Gastric Bypass for Morbid Obesity

Background: After open or laparoscopic Roux-en-Y gastric bypass (RYGBP) for morbid obesity, the bypassed stomach and duodenum are not readily available for radiological and endoscopic evaluation. Furthermore, little is known about the long-term physiologic and histologic changes that occur in the bypassed GI segments following these procedures. Many alternative radiological and endoscopic techniques have been described to access the distal gastric pouch and the duodenum after RYGBP. Apart from percutaneous gastrografin? studies, all these techniques require the insertion of a gastrostomy tube in the distal stomach. Methods: a new diagnostic method to access the bypassed segments by virtual CT gastroscopy (VG) was used in 5 morbidly obese patients who underwent laparoscopic RYGBP (LRYGBP). Results: All patients tolerated the procedure well, which appears safe and suitable for an outpatient setting.The virtual images offered an excellent intraluminal view of the stomach and duodenum. Conclusions: VG holds promise as the method of choice in the follow-up of LRYGB patients, having the potential to detect inflammatory changes and cancer in the excluded segments early.     

A Prospective Evaluation of Intracorporeal Laparoscopic Small Bowel Anastomosis during Gastric Bypass

Background: We evaluated the safety and feasibility of performing a laparoscopic intracorporeal end-toside small bowel anastomosis using a stapling technique as part of a Roux-en-Y gastric bypass operation (RYGBP). Methods: 80 consecutive patients who underwent RYGBP with laparoscopic jejunojejunostomy were evaluated. Operative time and intraoperative and postoperative complications directly related to the jejunojejunostomy anastomosis were recorded. Results: All 80 laparoscopic jejunojejunostomy procedures were successfully performed without conversion to laparotomy. Mean operative time was longer for the first 40 laparoscopic RYGBP than for the last 40 RYGBP (32±18 min vs 21±14 min, respectively, p<0.05). Intraoperative complications were staple-line bleeding (2 patients) and narrowing of the anastomosis (1 patient). Postoperative complications were four small bowel obstructions: technical narrowing at jejunojejunostomy site (2 patients), angulation of the afferent limb (1 patient), and food impaction at the jejunojejunostomy anastomosis (1 patient). These four patients underwent successful laparoscopic re-exploration and creation of another jejunojejunostomy proximal to the original anastomosis. There were no small bowel anastomotic leaks. The median time to resuming oral diet was 2 days. Conclusions: Laparoscopic jejunojejunostomy as part of the RYGBP operation is a safe and technically feasible procedure. Postoperative small bowel obstruction is a potential complication, which can be prevented by avoiding technical narrowing of the afferent limb.     

The Impact of Bariatric Surgery on Menstrual Patterns

Background: Obesity and anovulation are common medical problems in the United States. Anovulation in obese patients primarily manifests with irregular, sporadic or absent menstrual bleeding. Weight loss of at least 5% has been shown to reverse obesity-related anovulation. The aim of this study was to assess the impact of bariatric surgery on infertility in morbidly obese women and to identify factors associated with return of normal menses following bariatric surgery. Methods: A survey of patients was collected from the bariatric surgery data-base at the Hospital of the University of Pennsylvania. 410 women under the age of 40 were sent questionnaires. 195 patients completed the questionnaire, and 29 patients had incorrect addresses without a forwarding address, resulting in a 51.2% response rate. Patients who reported menstrual cycle lengths >35 days were considered abnormal. 92 of the 195 responders were considered anovulatory preoperatively, based on menstrual history. Results: There was no significant difference in postoperative BMI, BMI decrease or age at surgery between the survey responders and non-responders. There was a significant difference between these 2 groups in time since surgery (P=.01). Both groups had a decrease in BMI of >18 kg/m². The mean menstrual cycle length preoperatively among those categorized as ovulatory and anovulatory was 27.3 and 127.5 days, respectively. Of the 98 patients who were anovulatory preoperatively, 70 patients (71.4%) regained normal menstrual cycles after surgery. Those patients who regained ovulation had greater weight loss than those who remained anovulatory (61.4 kg vs 49.9 kg, P=0.02). Conclusions: Anovulation resulting in abnormal menses is a common problem in morbidly obese premenopausal women. The menstrual cycle disorders may completely resolve after bariatric surgery. Thus, infertility due to anovulation among morbidly obese women could potentially be viewed as an additional indication for bariatric surgery.