Posterior Aspiration

Autologous hematopoietic stem cells are obtained (or harvested ) from bone marrow or peripheral blood. The technique for harvesting autologous hematopoietic cells depends on the anatomic source (i.e., bone marrow or peripheral blood). A surgical procedure is necessary for obtaining bone marrow. Multiple aspirations of marrow are obtained from the anterior and posterior iliac crests until a volume with a sufficient number of hematopoietic cells is collected (i.e., 600-1200 mL of bone marrow). The bone marrow then is processed to remove fat or marrow emboli and usually is infused intravenously into the patient like a blood transfusion. 

Early on, bone marrow stem cells were harvested from the posterior and anterior iliac crests or the sternum, while the patient or donor was under a general anaesthetic. It was fairly rapidly established that a minimum number of nucleated cells was necessary to ensure engraftment, and that this related to the body weight of the recipient. At this point, it was not possible to identify the stem cells or early precursor cells immuno-logically, and a total nucleated cell count of the harvested material was obtained, into which the body weight of the recipient was divided in an attempt to ensure an adequate harvest. Normally, approximately 1 litre of harvested blood and marrow would be required to ensure the presence of a sufficient number of stem cells for an adult patient. The harvesting procedure would last for 1-2 h, depending on ease of aspiration, and... 

Airway. Airway protection in stroke patients may require immediate intervention. An impaired level of consciousness combined with emesis can occur in patients with increased intracranial pressure (ICP) and posterior circulation stroke. Vertebrobasilar ischemia may affect medullary respiratory centers and cause apnea, or more commonly, paralysis of pharyngeal and tongue musculature leading to obstruction of the airway. The patient may require gastric suction and intubation to protect the airway from aspiration of gastric contents. An oral airway or nasal trumpet can be helpful if the patient has an upper airway obstruction. 

The manual implantation of foldable lenses (Fig. 87) is substantially facilitated by and less complicated with a deep, stable anterior chamber and an evenly extended posterior capsule. For introduction of the folded lOL into the capsular bag (Fig. 88), lOL positioning before unfolding (Fig. 89) and the controlled unfolding in the capsular bag, viscoelastic substances of high viscosity and elasticity at low shear rates (e.g., Healon GV) should be applied. Following implantation, aspiration (Fig. 90) is more easily achieved with cohesive viscoelastic substances than with disperse viscoelastics. 

In a trial performed by Wedrich Menapace (1992), the removal of viscoelastic from behind the lOL lowered the incidence of early postop intraocular pressure peaks (Fig. 109). To mobilize OVD from behind the IOL,the irrigation/aspiration handle is generally lightly pressed onto the lOL optic. Moving the handle behind the lOL directly should be avoided so as not to aspirate the posterior capsule which would increase the danger of capsular damage (Wesendahl et al., 1994). 

Baker s cyst is usually asymptomatic and the patient s primary symptom is of a large mass or swelling in the posterior aspect of the knee. This bursal swelling may communicate with the knee joint space. It may be associated with osteoarthritis of the involved knee. It usually requires no treatment. Occasionally, it may require aspiration because of its size interfering with joint... 

The same day, VCU is performed commonly after suprapubic puncture (Fig. 6.3). Aspiration of stagnant urine is performed via a vesical catheter that can be left in place thereafter. All precautions must be taken to ensure sterility given the increased risk of post-procedural infection. Infection could be life threatening for the baby and devastating for renal function. Retrograde opacification would be technically possible since valves produce only one-way obstruction. However, it can be difficult to pass through the bladder neck due to the dilated posterior urethra, which can retain the tip of the tube. 

DeFriend DE, Schranz PJ, Silver DA (2001) Ultrasound-guided aspiration of posterior cruciate ligament ganglion cysts. Skeletal Radiol 30 411-414... 

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