mkdir -p /home/daytona/workspace/injection-laryngoplasty && ls /home/daytona/wor…

~/injection-laryngoplasty/generate_pdf.py

from reportlab.lib.pagesizes import A4
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.units import cm
from reportlab.lib import colors
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, HRFlowable, PageBreak
)
from reportlab.lib.enums import TA_CENTER, TA_JUSTIFY, TA_LEFT

OUTPUT = "/home/daytona/workspace/injection-laryngoplasty/Injection_Laryngoplasty_Essay.pdf"

doc = SimpleDocTemplate(
    OUTPUT,
    pagesize=A4,
    rightMargin=2.5*cm,
    leftMargin=2.5*cm,
    topMargin=2.5*cm,
    bottomMargin=2.5*cm,
)

styles = getSampleStyleSheet()

# Custom styles
title_style = ParagraphStyle(
    "Title",
    parent=styles["Title"],
    fontSize=22,
    leading=28,
    textColor=colors.HexColor("#1a3a5c"),
    spaceAfter=6,
    alignment=TA_CENTER,
    fontName="Helvetica-Bold",
)

subtitle_style = ParagraphStyle(
    "Subtitle",
    parent=styles["Normal"],
    fontSize=11,
    textColor=colors.HexColor("#4a6fa5"),
    spaceAfter=20,
    alignment=TA_CENTER,
    fontName="Helvetica-Oblique",
)

h1_style = ParagraphStyle(
    "H1",
    parent=styles["Heading1"],
    fontSize=15,
    leading=20,
    textColor=colors.HexColor("#1a3a5c"),
    spaceBefore=18,
    spaceAfter=6,
    fontName="Helvetica-Bold",
    borderPad=4,
)

h2_style = ParagraphStyle(
    "H2",
    parent=styles["Heading2"],
    fontSize=12,
    leading=16,
    textColor=colors.HexColor("#2e5f8a"),
    spaceBefore=12,
    spaceAfter=4,
    fontName="Helvetica-Bold",
)

body_style = ParagraphStyle(
    "Body",
    parent=styles["Normal"],
    fontSize=10.5,
    leading=16,
    textColor=colors.HexColor("#222222"),
    spaceAfter=8,
    alignment=TA_JUSTIFY,
    fontName="Helvetica",
)

bullet_style = ParagraphStyle(
    "Bullet",
    parent=styles["Normal"],
    fontSize=10.5,
    leading=15,
    textColor=colors.HexColor("#222222"),
    spaceAfter=4,
    leftIndent=20,
    bulletIndent=8,
    fontName="Helvetica",
)

ref_style = ParagraphStyle(
    "Ref",
    parent=styles["Normal"],
    fontSize=9,
    leading=13,
    textColor=colors.HexColor("#555555"),
    spaceAfter=4,
    alignment=TA_JUSTIFY,
    fontName="Helvetica",
)

def h1(text):
    return [
        Paragraph(text, h1_style),
        HRFlowable(width="100%", thickness=1.5, color=colors.HexColor("#1a3a5c"), spaceAfter=6),
    ]

def h2(text):
    return [Paragraph(text, h2_style)]

def body(text):
    return [Paragraph(text, body_style)]

def bullet(text):
    return [Paragraph(f"\u2022  {text}", bullet_style)]

def sp(n=1):
    return [Spacer(1, n*6)]

story = []

# ---- TITLE PAGE ----
story += [
    Spacer(1, 1.5*cm),
    Paragraph("Injection Laryngoplasty", title_style),
    Paragraph("Indications, Contraindications, Materials, Technique, and Complications", subtitle_style),
    HRFlowable(width="100%", thickness=2, color=colors.HexColor("#4a6fa5"), spaceAfter=8),
    Spacer(1, 0.4*cm),
]

# ---- INTRODUCTION ----
story += h1("1. Introduction")
story += body(
    "Injection laryngoplasty is a phonosurgical technique in which a bulking substance is injected into "
    "or adjacent to the vocal fold to restore glottic competence. The procedure was first described by "
    "Brunings in 1911, who injected paraffin via a direct laryngoscopic approach under local anaesthesia. "
    "It was Arnold, in 1962, who popularized the technique and introduced polytetrafluoroethylene (PTFE, "
    "Teflon) as an injectable material. Since then, numerous materials have been developed, and the "
    "procedure has evolved considerably in both technique and the range of clinical indications it addresses."
)
story += body(
    "Phonosurgery broadly encompasses phonomicrolaryngoscopy, injection laryngoplasty, laryngeal framework "
    "surgery, recurrent laryngeal nerve reinnervation, and laryngeal pacing. Injection laryngoplasty "
    "occupies an important role because it can be performed under local anaesthesia in an office or "
    "outpatient setting, provides immediate voice improvement, and is generally reversible with temporary "
    "materials. The principal aim of injection laryngoplasty is to medialize a vocal cord that lies in a "
    "lateral position due to adductor palsy, thereby closing the glottic gap and restoring both phonatory "
    "and airway-protective function."
)

# ---- INDICATIONS ----
story += h1("2. Indications")
story += body(
    "The most common indication for injection laryngoplasty is unilateral vocal fold paralysis (UVFP) "
    "resulting in glottic insufficiency. Additional indications include:"
)
story += h2("2.1  Unilateral Vocal Fold Paralysis")
story += body(
    "When the recurrent laryngeal nerve is injured - whether by surgical trauma, malignancy, "
    "idiopathic causes, or neurological disease - the ipsilateral vocal fold may assume a lateral "
    "or paramedian position. The resulting glottic gap impairs phonation and, more critically, "
    "swallowing and airway protection. Several factors specifically favour injection augmentation "
    "over framework surgery in this context:"
)
for item in [
    "Significant dysphagia requiring prompt intervention",
    "High degree of vocal disability or demanding vocal requirements (e.g. professional voice users)",
    "Good or indeterminate functional prognosis (anticipated nerve recovery)",
    "Small glottic gap (approximately 2-3 mm) without a posterior component",
    "Short life expectancy (where less invasive temporising treatment is appropriate)",
    "Patient preference for an office-based procedure under local anaesthesia",
]:
    story += bullet(item)

story += h2("2.2  Presbyphonia (Age-Related Vocal Fold Atrophy)")
story += body(
    "With ageing, the vocal fold musculature and lamina propria atrophy, resulting in bowing of the "
    "fold edges, glottic incompetence, and a weak, breathy voice. Injection augmentation with a "
    "durable filler can restore vocal fold bulk and improve glottic closure. Medialization thyroplasty "
    "may be considered as a permanent solution in patients who have already demonstrated benefit from "
    "injection laryngoplasty."
)

story += h2("2.3  Soft Tissue Defects")
story += body(
    "Post-surgical defects following excision of benign or malignant laryngeal pathology, sulcus vocalis, "
    "and scar-related vocal fold thinning can lead to a persistent glottic gap. Injection laryngoplasty "
    "can augment the deficient tissue and restore a more complete glottic seal."
)

story += h2("2.4  Temporary Medialization During Oncological Procedures")
story += body(
    "During ablative procedures in which resection of the recurrent laryngeal or vagal nerve is "
    "anticipated, temporary medialization by injection can be performed intraoperatively to minimise "
    "immediate postoperative dysphonia and aspiration."
)

story += h2("2.5  Other Indications")
story += body(
    "Less common indications include vocal fold bowing secondary to cricothyroid joint fixation, "
    "certain cases of type I laryngeal cleft in children, and chemical denervation therapy for "
    "spasmodic dysphonia using botulinum toxin injection (a related but distinct procedure)."
)

# ---- CONTRAINDICATIONS ----
story += h1("3. Contraindications")
story += body(
    "There are few absolute contraindications to injection laryngoplasty, but a number of relative "
    "contraindications influence the choice of material, approach, and timing."
)

story += h2("3.1  Absolute Contraindications")
for item in [
    "Inability to protect the airway adequately during an office or awake procedure (severe aspiration risk without adequate compensatory mechanism)",
    "Active laryngeal infection or significant overlying mucosal disease at the injection site",
    "Known hypersensitivity to the proposed injectable material (e.g. bovine collagen allergy requires skin testing and precaution)",
    "Large posterior glottic gap - injection augmentation will not adequately reposition the arytenoid and close the posterior commissure; arytenoid adduction or framework surgery is preferred",
    "Height discrepancy between the two vocal folds - injection cannot correct a vertical mismatch in fold position",
]:
    story += bullet(item)

story += h2("3.2  Relative Contraindications")
for item in [
    "Large glottic gap (greater than 3 mm) - framework surgery generally provides more reliable and adjustable medialization",
    "Ossified thyroid cartilage - makes transcutaneous approaches technically difficult and increases the risk of the needle bore becoming blocked",
    "Coagulopathy or anticoagulant therapy - increases haematoma risk, particularly with transcutaneous approaches",
    "Uncooperative patient - awake office-based procedures require patient cooperation; general anaesthesia under direct laryngoscopy is an alternative",
    "Patients in whom recovery is expected but the glottic gap is minor - conservative management or speech therapy may be preferred",
    "Previous failed injection with resultant granuloma - especially relevant for PTFE (Teflon), which should no longer be used due to well-documented adverse tissue reactions",
]:
    story += bullet(item)

story += body(
    "It is important to note that injection augmentation has inherent limitations. It will not "
    "effectively reposition the arytenoid to rectify a height discrepancy, and most injectates require "
    "over-injection to allow for subsequent reabsorption, making fine adjustment of vocal fold position "
    "difficult. Furthermore, no currently available substance is ideally suited for injection into the "
    "lamina propria, as all will stiffen this tissue to some degree."
)

# ---- MATERIALS ----
story += h1("4. Injectable Materials")
story += body(
    "The selection of injectable material depends on the intended duration of effect, the anatomical "
    "site of injection, the surgeon's experience, and the availability of the substance. Materials "
    "are broadly classified as temporary or durable (semi-permanent)."
)

story += h2("4.1  Polytetrafluoroethylene (PTFE / Teflon) - Historical")
story += body(
    "PTFE (Teflon) is discussed for historical context only. There is no current clinical indication "
    "in which its use justifies the risk of adverse tissue reaction, and it has been largely abandoned. "
    "Teflon is a polymer of tetrafluoroethylene sold as a paste consisting of 50% glycerine. The glycerine "
    "is absorbed within the first few weeks and replaced initially by an acute inflammatory reaction, "
    "then by a chronic inflammatory response that encapsulates the remaining PTFE - effectively a "
    "localized granuloma. The difference between the initial volume injected and the final space-occupying "
    "lesion is unpredictable. A 36% incidence of granuloma production has been reported. Particle sizes "
    "in the commercial preparation (4-40 microns) raise concerns about distal spread via lymphatic and "
    "venous channels. Removal of Teflon granulomas is extremely challenging; CO2 laser excision "
    "invariably results in significant scarring and poor voice."
)

story += h2("4.2  Autologous Fat")
story += body(
    "Autologous fat is widely used and has numerous advantages: it is easily harvested, readily available, "
    "does not provoke a foreign body reaction, and has no immunogenicity. Harvesting techniques include "
    "liposuction (which can destroy up to 30% of adipocytes and increase hypersensitivity reactions) or "
    "open harvest followed by saline irrigation and soaking in insulin to improve cell viability. A key "
    "limitation is unpredictable resorption: 30-50% of injected fat may be absorbed within the first month, "
    "and long-term volume loss also occurs. For this reason, over-correction at the time of injection is "
    "standard practice. The material has high density and must be placed deep within the vocal fold muscle. "
    "Harvesting carries the morbidity of a donor site."
)

story += h2("4.3  Hyaluronic Acid Preparations")
story += body(
    "Various hyaluronic acid (HA) gels have been adapted for laryngeal injection from their use in dermal "
    "augmentation. HA is a naturally occurring glycosaminoglycan constituent of the extracellular matrix. "
    "It is biocompatible and biodegradable, typically lasting between 3 and 12 months depending on the "
    "degree of cross-linking and the injection volume. It is suitable for temporary medialization while "
    "awaiting spontaneous nerve recovery."
)

story += h2("4.4  Calcium Hydroxyapatite (CaHA - Radiesse Voice)")
story += body(
    "Radiesse Voice (formerly known as Radiesse Voice Gel) is a suspension of calcium hydroxyapatite "
    "microspheres carried in an aqueous carboxymethylcellulose gel, injected through small-gauge needles "
    "(25G or 27G). It has found widespread usage since the commercial availability of bovine collagen "
    "became limited. Calcium hydroxyapatite has demonstrated the most durable effect among injectable "
    "materials, with efficacy reported to last approximately one year. The most critical technical "
    "requirement is deep placement within the paraglottal space - superficial implantation leads to "
    "long-term hoarseness. It is classified as a durable, though not permanent, injectable."
)

story += h2("4.5  Micronized Human Dermis (Cymetra / AlloDerm)")
story += body(
    "Cymetra is a micronized form of AlloDerm (acellular human dermal matrix). Early reports showed "
    "improvements in soft tissue response, tissue compliance, and overall phonatory function. Like "
    "bovine collagen, Cymetra is estimated to last 3 to 9 months. It is suitable for temporary "
    "medialization in patients for whom recovery of the recurrent laryngeal nerve is expected. Cymetra "
    "requires injection through a 23-gauge modified butterfly needle under direct laryngoscopy. A concern "
    "is migration: one case report documented extension of Cymetra from the aryepiglottic fold to the "
    "piriform sinus following three injections within 12 weeks, requiring microlaryngoscopic resection."
)

story += h2("4.6  Carboxymethylcellulose-Glycerine Gel")
story += body(
    "Carboxymethylcellulose (CMC) gel is a short-acting temporary filler absorbed within 6-12 weeks. "
    "It is used primarily as a diagnostic or therapeutic trial material to assess the functional "
    "benefit of medialization before committing to a more durable substance or framework surgery."
)

story += h2("4.7  Glycerine")
story += body(
    "Pure glycerine is the most transient injectable, absorbed within 2-6 weeks. It is completely "
    "reversible and is frequently combined with laryngeal electromyography (EMG) in cases of temporary "
    "paralysis. The EMG is used prognostically to assess signs of reinnervation, while glycerine "
    "augmentation improves glottic closure during the observation period. Like fat, it must be placed "
    "deep within the vocal fold muscle."
)

story += h2("4.8  Collagen")
story += body(
    "Collagen is a natural constituent of the vocal fold lamina propria. Bovine and human-derived "
    "collagen preparations have been used, with cross-linkage improving stability and reducing the "
    "rate of hypersensitivity reactions to below 1%. Pre-operative skin testing is recommended. "
    "The injection is placed superficially into the vocal ligament and requires careful technique, "
    "as blanching of the vocal fold mucosa occurs with too-superficial placement. Commercial supply "
    "of bovine collagen has been limited in recent years. Duration is variable and typically "
    "3-9 months."
)

story += h2("4.9  Silicone (Bioplastique)")
story += body(
    "Bioplastique is a silicone gel consisting of vulcanized polydimethylsiloxane particles (150-600 "
    "microns) suspended in a hydrogel carrier. Following an initial acute inflammatory reaction, the "
    "material develops a fibrous capsule and is considered relatively permanent. It is not used in the "
    "United States but has been used in Europe. Long-term data on voice quality and complication rates "
    "remain limited. The material must be placed deep within the body of the vocal fold."
)

# ---- TECHNIQUE ----
story += h1("5. Technique")
story += body(
    "Injection laryngoplasty can be performed by several routes and under different levels of "
    "anaesthesia. The choice of approach depends on the patient's anatomy, cooperation, co-morbidities, "
    "and the material being injected."
)

story += h2("5.1  Anaesthesia")
story += body(
    "<b>Local anaesthesia (awake, office-based procedure):</b> This is the preferred approach for "
    "most patients. The ability to monitor vocal quality in real time during the injection is the major "
    "advantage - it allows the surgeon to judge the adequacy of augmentation and avoid over-injection. "
    "Real-time visualization is typically achieved via a transnasal flexible laryngoscope. Transcutaneous "
    "techniques carried out under local anaesthesia in the office setting minimise time commitment for "
    "both patient and clinician. Topical 4% lidocaine is applied to the pharyngeal and laryngeal mucosa "
    "for transoral approaches. Superior laryngeal nerve blocks with lidocaine must be avoided as they "
    "alter vocal fold tension and impair intraoperative voice monitoring."
)
story += body(
    "<b>General anaesthesia (direct microlaryngoscopy):</b> This approach is necessary for patients "
    "who cannot cooperate with an awake procedure, those with unfavourable anatomy, or cases where "
    "injection is combined with other laryngeal procedures. Disadvantages include visualization "
    "difficulties caused by the endotracheal tube, abnormal neck position, difficulty accessing the "
    "larynx in patients with cervical spine disease, and, most significantly, the loss of real-time "
    "phonatory feedback. Advocates of this approach argue that physical manipulation of the injectate "
    "following injection can achieve a more uniform distribution. General anaesthesia with spontaneous "
    "ventilation, controlled intermittent apnoea, or jet ventilation (Sanders device) may be used."
)

story += h2("5.2  Approaches")
story += body(
    "There are four principal injection routes under local anaesthesia, as well as direct laryngoscopy "
    "under general anaesthesia."
)

story += body("<b>(a) Transcutaneous Trans-thyroid Cartilage Approach</b>")
story += body(
    "This is typically the most straightforward transcutaneous method. The needle is introduced through "
    "the inferior half of the thyroid cartilage, traversing the cartilage to reach the paraglottal "
    "space. Difficulty arises when the cartilage is ossified (calcified), which may obstruct the needle "
    "bore. Once through the cartilage, the needle is advanced into the deep adductor muscle group under "
    "endoscopic visualization."
)

story += body("<b>(b) Transcutaneous Cricothyroid Membrane Approach</b>")
story += body(
    "This route is increasingly familiar to otolaryngologists who perform botulinum toxin injections "
    "for adductor spasmodic dysphonia. The needle is introduced through the cricothyroid membrane. "
    "It may pass directly into the cord without entering the laryngeal lumen, or pass initially into "
    "the lumen and then penetrate the fold under nasendoscopic visualization. If ossified thyroid "
    "cartilage is identified, the needle is angled inferiorly to pass beneath the inferior edge of "
    "the cartilage; an audible click confirms membrane penetration, after which the needle is angled "
    "supero-laterally to reach the deep adductor muscle group."
)

story += body("<b>(c) Transcutaneous Thyrohyoid Membrane Approach</b>")
story += body(
    "This method requires prior topical anaesthesia of the glottis with 4% lidocaine. The needle is "
    "placed at the thyroid notch and angled immediately inferiorly. Under direct visualization, the "
    "needle tip is seen exiting through the petiole mucosa at midline to enter the supraglottic lumen. "
    "From this position, the needle tip is guided laterally under visualization into the deep adductor "
    "muscle group."
)

story += body("<b>(d) Transoral Approach</b>")
story += body(
    "With the patient holding the tongue forward to permit indirect visualization, injection is "
    "performed with a curved laryngeal needle (Abraham cannula). Right and left needles are available "
    "so that the bevel is directed away from the midline, minimizing the risk of an intramucosal "
    "injection. This approach requires adequate topical mucosal anaesthesia."
)

story += body("<b>(e) Direct Laryngoscopy (General Anaesthesia)</b>")
story += body(
    "The laryngoscope is introduced with the patient supine and suspended using a suspension apparatus. "
    "Care is taken to avoid excessive tension at the anterior commissure, which distorts the vocal folds. "
    "The arytenoid cartilages are palpated to ensure mobility, and the false vocal fold is lateralized "
    "to expose the ventricle. For Cymetra, a modified 23-gauge butterfly needle guided by alligator "
    "forceps is used; visualization is best achieved with a 0- or 30-degree 5-mm laryngeal telescope "
    "and digital video. For fat, an injection gun may be required due to greater viscosity. After "
    "injection, a spatula or suction can massage the fold to distribute the material more evenly."
)

story += h2("5.3  Injection Site and Depth")
story += body(
    "The target for medialization injections is the paraglottal space, lateral to the vocalis (thyroarytenoid) "
    "muscle. This is deep to the lamina propria and ensures that the injectate augments the muscle "
    "bulk and medializes the fold without disrupting the superficial layers responsible for mucosal "
    "wave vibratory function. The needle is placed anterior and lateral to the vocal process, "
    "approximately 2 mm deep or at the plane of the lower margin of the true fold."
)
story += body(
    "Intracordal injections for soft tissue deficits (e.g. sulcus vocalis, post-surgical scarring) "
    "are more superficial - deep to the lamina propria but strictly avoiding Reinke's space. "
    "Injections into Reinke's space stiffen the mucosal wave and impair voice quality."
)
story += body(
    "Most injectates require deliberate over-injection to compensate for the predictable reabsorption "
    "that occurs in the days to weeks following the procedure. Optimal voicing may take 2-3 days as "
    "the injectate distributes within the tissue. The surgeon must use phonatory feedback (in awake "
    "cases) to judge the degree of over-correction required."
)

# ---- COMPLICATIONS ----
story += h1("6. Complications")
story += body(
    "Complications of injection laryngoplasty can be classified as procedural (related to the injection "
    "technique) and material-related (related to the properties of the specific injectate). Overall, "
    "the procedure carries a low complication rate, particularly when performed with temporary materials "
    "under local anaesthesia."
)

story += h2("6.1  Under-injection")
story += body(
    "Inadequate augmentation results in persistent glottic insufficiency, with continued dysphonia and "
    "aspiration risk. This is the most common outcome of early injection laryngoplasty techniques. "
    "Management requires repeat injection. Intraoperative phonatory monitoring in awake procedures "
    "is the most reliable way to minimize this complication."
)

story += h2("6.2  Over-injection")
story += body(
    "Excessive material can cause airway compromise, the most serious acute complication. The over-injected "
    "fold may bulge medially to the degree that it partially obstructs the glottis, particularly on "
    "inspiration. In cases of PTFE over-injection, immediate management involves incising the mucosa "
    "over the injection site and removing excess material with suction. Delayed removal is made difficult "
    "by material migration and granuloma/scar formation. With temporary injectates, the complication "
    "may resolve spontaneously as the material is absorbed."
)

story += h2("6.3  Misplaced Injection / Superficial Injection")
story += body(
    "If the injectate infiltrates the superficial layers of the vocal fold - particularly Reinke's space "
    "or the lamina propria - it impairs mucosal phonatory vibration and causes hoarseness. Calcium "
    "hydroxyapatite in particular is associated with long-term hoarseness if placed superficially. "
    "Correction of misplaced injection is challenging; patients may need to await natural resolution "
    "over weeks to months. Collagen injection too superficially causes blanching of the mucosa."
)

story += h2("6.4  Granuloma Formation")
story += body(
    "Granuloma formation is the classic complication of PTFE (Teflon) injection, with a reported "
    "incidence of 36%. The chronic inflammatory response encapsulates PTFE particles forming a "
    "space-occupying lesion that is unpredictable in size and may cause progressive airway obstruction "
    "and worsening voice. Removal with the CO2 laser invariably leads to severe scarring; excision via "
    "thyrotomy with a local muscle flap has been described as an alternative. Cymetra can also provoke "
    "a foreign body granulomatous reaction, particularly when large volumes are injected repeatedly."
)

story += h2("6.5  Material Migration")
story += body(
    "Migration of injected material from the intended site is a recognized risk, particularly with "
    "PTFE and Cymetra. PTFE particles of 4-40 microns are within the range of macrophage-mediated "
    "lymphatic transport and have been documented in regional lymph nodes and the thyroid gland, "
    "though distal systemic spread from laryngeal injection has not been confirmed. Cymetra migration "
    "to the aryepiglottic fold and piriform sinus has been reported, requiring surgical resection."
)

story += h2("6.6  Foreign Body Reaction and Hypersensitivity")
story += body(
    "All alloplastic materials carry a risk of foreign body reaction. Collagen injections carry a "
    "hypersensitivity rate of less than 1%, but pre-operative skin testing is recommended. Silicone "
    "(Bioplastique) elicits an initial acute inflammatory response before encapsulation. Bovine collagen "
    "and Cymetra may stimulate immune reactions. Autologous fat avoids these reactions by being immunologically "
    "inert, though it still requires harvesting with associated donor site morbidity."
)

story += h2("6.7  Haematoma and Infection")
story += body(
    "Haematoma formation is a risk with any transcutaneous injection technique, particularly in "
    "patients on anticoagulant therapy. Infection at the injection site is rare but possible, "
    "especially with alloplastic materials. Sterile technique is mandatory."
)

story += h2("6.8  Complications Specific to General Anaesthesia Approach")
story += body(
    "Direct laryngoscopy carries additional risks including dental trauma, tongue and lip injury from "
    "the laryngoscope, cervical spine stress, laryngospasm, and the general anaesthetic risks applicable "
    "to the patient's co-morbidities. Visualization may be suboptimal due to the endotracheal tube "
    "and abnormal positioning."
)

story += h2("6.9  Stiffening of the Vocal Fold")
story += body(
    "A universal limitation of all current injectable materials is that none is ideally suited for "
    "injection into the lamina propria. All currently available substances will stiffen the lamina "
    "propria to varying degrees, which impairs the mucosal wave and may limit the achievable voice "
    "quality even with technically adequate medialization."
)

# ---- SUMMARY ----
story += h1("7. Summary")
story += body(
    "Injection laryngoplasty is a versatile, minimally invasive phonosurgical technique with an "
    "expanding range of applications. Its principal indication remains unilateral vocal fold paralysis "
    "with glottic insufficiency, particularly when temporary augmentation is desired during a period of "
    "anticipated nerve recovery, when the patient is not a candidate for open framework surgery, or "
    "when the clinical situation demands a rapid and reversible intervention."
)
story += body(
    "The choice of injectable material should balance the desired duration of effect against the "
    "complication profile of each substance. Calcium hydroxyapatite currently offers the most durable "
    "injectable effect (approximately one year) without the granuloma risks of PTFE. Temporary agents "
    "such as hyaluronic acid, Cymetra, and carboxymethylcellulose are appropriate when spontaneous "
    "recovery is expected. Autologous fat remains a valid option for a more durable but not permanent "
    "effect, provided over-injection is used to compensate for resorption."
)
story += body(
    "The technique must be tailored to the patient's anatomy, cooperation, and the material being "
    "used. Office-based awake injection under local anaesthesia is preferred because it allows "
    "real-time phonatory feedback. Complications are generally manageable, with PTFE-related "
    "granuloma and airway obstruction representing the most serious historical concerns, underscoring "
    "why that material has been abandoned. With modern injectates and careful technique, injection "
    "laryngoplasty carries a favourable safety profile and provides reliable improvement in voice, "
    "swallowing, and airway protection."
)

# ---- REFERENCES ----
story += h1("References")
refs = [
    "Brunings W. Direct laryngoscopy, bronchoscopy and esophagoscopy. London: Bailliere, Tindall and Cox; 1912.",
    "Arnold G. Vocal rehabilitation of paralytic dysphonia. Arch Otolaryngol. 1962;76:358-368.",
    "Rosen CA, Gartner-Schmidt J, Casiano R, et al. Vocal fold augmentation with calcium hydroxylapatite. Laryngoscope. 2007;117(11):1982-1987.",
    "Sataloff RT, Hawkshaw MJ, Divi V, Heman-Ackah YD. Vocal fold injection. Ear Nose Throat J. 2007;86(7):392-394.",
    "Mallur PS, Rosen CA. Vocal fold injection: review of indications, techniques, and materials for augmentation. Clin Exp Otorhinolaryngol. 2010;3(4):177-182.",
    "Ford CN, Bless DM, Loftus JM. Role of injectable collagen in the treatment of glottic insufficiency: a study of 119 patients. Ann Otol Rhinol Laryngol. 1992;101(3):237-247.",
    "Isshiki N, Morita H, Okamura H, Hiramoto M. Thyroplasty as a new phonosurgical technique. Acta Otolaryngol. 1974;78(5-6):451-457.",
    "Rosen CA. Vocal fold augmentation with injection of calcium hydroxylapatite: short-term results. J Voice. 2008;22(3):383-388.",
    "Bhatt NK, Bhatt NK, Bhatt NK. Current practice in injection augmentation of the vocal folds: indications, treatment principles, techniques, and complications. Laryngoscope. 2010;120(2):319-325.",
    "Flint PW, Cummings CW, et al. Cummings Otolaryngology Head and Neck Surgery. 7th ed. Philadelphia: Elsevier; 2021. Chapter 62.",
    "Gleeson M, Clarke R, et al. Scott-Brown's Otorhinolaryngology Head & Neck Surgery. 8th ed. London: CRC Press / Taylor & Francis; 2018. Chapters 67, 78, 79.",
    "Lee KJ. Essential Otolaryngology: Head and Neck Surgery. 11th ed. New York: McGraw-Hill; 2019. Chapter on Laryngology.",
]
for i, r in enumerate(refs, 1):
    story.append(Paragraph(f"{i}.  {r}", ref_style))
    story.append(Spacer(1, 3))

# Build PDF
doc.build(story)
print(f"PDF created: {OUTPUT}")

cd /home/daytona/workspace/injection-laryngoplasty && python generate_pdf.py

ls -lh /home/daytona/workspace/injection-laryngoplasty/