Further augmentation to lateral wall implant, w/ hydroxyap
Dear Dr. Houser, A few questions regarding the potential use of hydroxyapatite cement to further augment an existing alloderm implant: 1. In your opinion, do you feel that the HA would disrupt/ constrict the vascular blood flow that is in place under the current lateral wall implant? (e.g. cause necrosis of that local) 2. Would pourous hydroxy, rather than regular hydroxy allow for more blood vessel growth, or is that not as relevant per the alloderm? 3. Have you heard any updates from Dr. Rice regarding the past attempts using HA to bulge out the IT? Thank you very much, -Matt

I do not think the alloderm overlying an HA implant would suffer. As we are finding out the bone supplies too little blood to the alloderm, whereas the mucosa and cartilage supply abundant blood. Raising an older alloderm graft off the bone should not harm it. Hydroxy form may allow more vessels to grow in, but it is in a solid scaffold - hard to get it into the necessary space. It could be crushed or broken into small segments but I wonder if the ingrowth potential is minimized. The liquid "injectable" would likely fill the space more thoroughly but be a more solid block. The issue of vessels is mainly one of heating the inspired air - if a thick carpet of alloderm exists above the HA then I am not sure if the deep HA matters much. Trade offs between the 2 - I need to talk to a rep to learn more. Orthopods use this stuff regularly, not ENTs. I have never spoken to Dr. Rice re: his one case report on IT rebuilding. I am not sure how the patient did.

Case report A 42-year-old woman came to the otolaryngology department for an examination. She had undergone two previous operations for nasal obstruction and chronic sinusitis sinusitis /si·nus·itis/ (si?nu-si´tis) inflammation of a sinus. -------------------------------------------------------------------------------- si·nus·i·tis (sn, both on the left side. At the time of her examination, she complained of paradoxical airway obstruction, dryness, crusting, and chronic sinusitis. Her nasal examination was remarkable for a small amount of mucopurulent mucopurulent /mu·co·pu·ru·lent/ (-pur´ah-lint) containing both mucus and pus. -------------------------------------------------------------------------------- mu·co·pu·ru·lent (myk drainage from the middle meatus acoustic meatus , auditory meatus either of two passages in the ear, one leading to the tympanic membrane (external acoustic m.), and one for passage of nerves and blood vessels (internal acoustic m.) . nasal meatus one of the four portions (common, inferior, middle, and superior) of the nasal cavity on either side of the septum. and a complete absence of the inferior turbinate on the left side (figure 1). After a long discussion, the physician and patient decided that she would undergo endoscopic sinus surgery and an attempt to reconstruct the inferior turbinate with hydroxyapatite cement. The reconstruction of the inferior turbinate was accomplished by making an incision on the lateral nasal wall from the attachment of the inferior turbinate inferiorly. A subperiosteal tunnel was carefully fashioned along the entire anterior-posterior length of the nasal cavity. Following this, the hydroxyapatite cement was mixed slightly wetter than is normally the case and injected through a large syringe with an attached large-bore catheter to fill the subperiosteal pocket. After the material was held in place for a few moments, it tended to remain in place without additional effort. The remainder of the procedure was accomplished in the usual manner. Three months later, the patient had a stable, well-formed inferior turbinate (figure 2), which was still maintained 1 year after the procedure. Discussion The author has performed similar reconstructions in other patients with Gortex and with AlloDerm, and all have healed without incident and with little loss of volume over 6 to 12 months of followup followup - On Usenet, a posting generated in response to another posting (as opposed to a reply, which goes by e-mail rather than being broadcast). Followups include the ID of the parent message in their headers; smart news-readers can use this information to present Usenet news in "conversation" sequence rather than order-of-arrival. See thread.. Whether these materials maintain their volume over a longer period of time remains to be seen. The potential for adverse effects such as infection or rejection also remains uncertain at this time. From the Department of Otolaryngology-Head and Neck Surgery, University of Southern California School of Medicine, Los Angeles. Reference (1.) Moore ES, Reder PA, Kern EB. Atrophicatrophic /atro·phic/ (a-tro´fik) pertaining to or characterized by atrophy. ..... Click the link for more information. rhinitis: A review of 222 cases. Presented at the American Rhinologic Society meeting; May 1997; Scottsdale, Ariz.

that is the case never any f/u reported

interesting

I met with a rep from Stryker that makes an injectable HA product (2nd generarion from that used in Dr. Rice's article). It looks very promising. It is osteoconductive - allows for bone ingrowth to the material. The porous materials apparently have less longevity. Neither can be used in a load bearing area (nose is not load bearing anyways) A pocket below the original graft could be created and the pocket filled with the material. I emailed Dr. Rice 1 wk ago re: his case but no reply.

Wow, that sounds promising indeed. If it's something you feel comfortable with, I am eagerly considering it to augment the initial alloderm. When HA has been used in other parts of the body, does it appear to retain long-term volume? Thanks for the update Dr. Houser, much appreciated.