instruction:
Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
question:
Context: Spinal anesthesia can be challenging in patients undergoing total joint arthroplasty because of poorly palpable surface landmarks and age-related changes in the lumbar spine. We hypothesized that pre-procedural ultrasound imaging would be effective in identifying the lumbar intervertebral spaces and would provide an accurate measure of the depth to the intrathecal space.', "Fifty patients undergoing elective total joint arthroplasty were recruited in this prospective descriptive study. Using a curved-array 2-5 MHz transducer, the lumbar spine was imaged in two views, i.e., longitudinal parasagittal (LP) and transverse midline (TM). The intervertebral levels were identified by counting upwards from the sacrum. The locations of the interlaminar spaces were identified by visualizing the ligamentum flavum-dura mater complex and the posterior aspect of the vertebral body. The needle insertion point for a midline approach was determined from the ultrasound examination and was marked on the skin of the patient's back.", 'The mean patient age was 67 +/- 10 yr, and 46% of the patients had a body mass index >30 kg . m(-2). Surface landmarks were difficult or impossible to palpate in 38% of the patients. The scan quality on the LP and TM views was adequate or better in 100 and 98% of the patients, respectively. Dural puncture was achieved with one needle insertion attempt and within two needle insertion attempts in 84% and 98% of the patients, respectively. The ultrasound-measured depth to the intrathecal space correlated well with the actual needle insertion depth (concordance correlation coefficient = 0.82, accuracy 0.95, precision 0.86), with a tendency to overestimate the depth by just 2.1 +/- 5.4 mm.
Answer: Ultrasound imaging of the lumbar spine provides clinically useful information that can facilitate spinal anesthesia in the older orthopedic patient population.
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Does an ultrasound-assisted approach facilitate spinal anesthesia for total joint arthroplasty?

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Context: Many bacterial meningitis patients experience neurological or neuropsychological sequelae, predominantly deficits in short-term memory, learning, and attention. Neuropsychological symptoms after viral meningitis are observed less frequently. Sleep disturbance has been reported after both viral and bacterial meningitis.', 'To examine systematically the frequency and extent of sleep disturbance in meningitis patients.', 'Eighty six viral or bacterial meningitis (onset of acute disease at least 1 year previously) patients were examined using two standardised questionnaires (Schlaffragebogen B and the Pittsburgh Sleep Quality Index, PSQI) in conjunction with a standardised neurological examination, and compared to a control group of 42 healthy age-matched volunteers.', 'Patients after both viral and bacterial meningitis described their sleep as reduced in quality and less restful than that of healthy control subjects; both patient groups had a pathological mean PSQI total score. Impaired sleep scores after meningitis were not correlated to either the Glasgow Coma Scale or the Glasgow Outcome Scale. Moreover, no relationship between residual neurological dysfunction or depressivity and sleep quality was observed.
Answer: Impaired sleep is a long-term consequence of meningitis. Additional, so far undetermined, factors other than the severity of concomitant neurological deficits are responsible for the development of this sequela.
answer:
Are sleep disorders long-term sequelae of both bacterial and viral meningitis?

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Context: We evaluated the incidence of cryptorchidism and inguinal hernias in patients with posterior urethral valves, and compared characteristics in patients with and without cryptorchidism or inguinal hernia.', 'A total of 200 patients with posterior urethral valves treated between 1953 and 2003 were identified from a hospital database. Patient records were retrospectively reviewed. The state of testicular descent and the presence of inguinal hernias were recorded in 192 patients. Patient characteristics were analyzed.', 'Of 192 patients 31 (16%) had cryptorchidism, which was bilateral in 9 (29%). A total of 21 patients (11%) had inguinal hernias that were not associated with cryptorchid testes. The patients with cryptorchidism, and to some extent the patients with hernias, appeared to have a more severe form of posterior urethral valves than those without cryptorchidism. At the time of diagnosis the median serum creatinine concentration was 100 mumol/l (range 38 to 460) in boys with cryptorchidism and 87 (14 to 593) in boys without cryptorchidism (p = 0.131). At 6-month followup the median serum creatinine levels were 90 mumol/l (range 31 to 573) in patients with cryptorchidism and 45 (19 to 504) in patients without cryptorchidism (p = 0.006). Cryptorchidism was also more common in cases diagnosed neonatally compared to those diagnosed at a later age (14 of 52 patients, 27% vs 14 of 112, 12.5%, respectively, p = 0.027).
Answer: The incidence of cryptorchidism and inguinal hernias requiring surgery is high in patients with posterior urethral valves. Patients with cryptorchidism appear to have a more severe form of posterior urethral valves than those with normal testes.
answer:
Are posterior urethral valves often associated with cryptorchidism and inguinal hernias?